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Robotic Spacecraft (Astronomy, Planetary, Earth, Solar/Heliophysics) => Space Science Coverage => Topic started by: bolun on 11/27/2010 10:19 pm

Title: ESA - LISA Pathfinder updates
Post by: bolun on 11/27/2010 10:19 pm
The Mission:

LISA Pathfinder will pave the way for the LISA mission by testing in flight the very concept of the gravitational wave detection: it will put two test masses in a near-perfect gravitational free-fall and control and measure their motion with unprecedented accuracy. This is achieved through state-of-the-art technology comprising the inertial sensors, the laser metrology system, the drag-free control system and an ultra-precise micro-propulsion system.

Launch Date: 2015 
Mission End: The operational phase will last about 12 months
Launch Vehicle: Vega launcher
Launch Mass: 1900 kg
Mission Phase: Implementation
 
Orbit: Operational orbit is a Halo orbit around the first Earth-Sun Lagrange point (L1) after a transfer trajectory from a low Earth parking orbit
Objetives: LISA Pathfinder is to demonstrate the key technologies to be used in the future LISA mission

http://sci.esa.int/science-e/www/area/index.cfm?fareaid=40 (http://sci.esa.int/science-e/www/area/index.cfm?fareaid=40)

Edit: Launch date updated.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 05/20/2011 08:11 pm
ST7, NASA's involvement in LISA Pathfinder mission.

http://nmp.jpl.nasa.gov/st7/

http://science.nasa.gov/missions/st-7/

http://science.nasa.gov/about-us/smd-programs/physics-of-the-cosmos/
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 10/28/2011 01:51 pm
http://www.arianespace.com/news-press-release/2011/10-28-2011-vega-contract.asp

Quote
Studies under way for the LISA Pathfinder mission

The studies for the launch of the LISA Pathfinder scientific satellite of ESA, using a Vega launcher from the Verta batch, started at the end of September. The mission is scheduled for a launch window from October 2013 to September 2014.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 11/14/2011 07:34 pm
LISA Pathfinder takes major step in hunt for gravity waves
 
14 November 2011

Sensors destined for ESA’s LISA Pathfinder mission in 2014 have far exceeded expectations, paving the way for a mission to detect one of the most elusive forces permeating through space – gravity waves.
 
The Optical Metrology Subsystem underwent its first full tests under space-like temperature and vacuum conditions using an almost complete version of the spacecraft.

The results exceeded the precision required to detect the enigmatic ripples in the fabric of space and time predicted by Albert Einstein – and did it by two to three times.

http://www.esa.int/esaSC/SEMX61WWVUG_index_0.html
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 06/11/2013 03:35 pm
Paving the way for the world’s first gravitational wave detector

6 Jun 2013

New space technology vital for detecting the elusive phenomenon of gravitational waves is now ready to endure the tremendous forces of a rocket launch, after passing vital tests right here in the UK.

The new technology is the optical bench of the LISA (Laser Interferometer Space Antenna) Pathfinder mission – a spacecraft that aims to prove essential key technologies for future gravitational-wave observatories, such as the proposed LISA mission.

Built and tested at the Institute for Gravitational Research (IGR) at the University of Glasgow, the optical bench has now been shipped to Astrium in Germany for integration with the rest of the Science Module.

LISA Pathfinder could pave the way to a completely new ‘view’ of the Universe, complementing our understanding of its evolution. The mission aims to demonstrate the new technology needed for future gravitational-wave observatories to trace the formation, growth, and merger history of massive black holes. This new information could tell us more about the way space and time are interconnected.

http://www.bis.gov.uk/ukspaceagency/news-and-events/2013/Jun/paving-the-way-for-the-worlds-first-gravitational-wave-detector


Image credit: Paul Gavin/IGR/AEI/Milde Science Communication.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 07/10/2013 08:36 pm
Latest LISA Pathfinder hardware delivery is 'Jewel in the Crown'

24 June 2013

A team of scientists from the University of Glasgow has successfully delivered a significant milestone for LISA Pathfinder - the flight optical bench. This glittering piece of hardware has very demanding requirements; tests have shown that these have been exceeded. Following formal delivery to Astrium GmbH, on 21 June, the optical bench is ready for integration onto the LISA Technology Package (LTP).

http://sci.esa.int/lisa-pathfinder/51961-latest-lisa-pathfinder-hardware-delivery-is-jewel-in-the-crown/

Image credit: University of Glasgow and University of Birmingham
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 12/16/2013 08:08 pm
Inertial Sensor Head shaken but not disturbed

12 December 2013 12:12

The Engineering Qualification Model of the Inertial Sensor Head (ISH) for LISA Pathfinder has passed a significant milestone. The integration of all the components of the ISH with perfect alignment, and the successful completion of qualification tests mark the first time that a heavy test mass inertial sensor has been assembled and successfully tested.

http://sci.esa.int/lisa-pathfinder/53349-inertial-sensor-head-shaken-but-not-disturbed/

Image credit: RUAG & CGS
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 01/02/2015 07:59 pm
http://www.esa.int/About_Us/ESA_Publications/ESA_Publications_Bulletin/ESA_Bulletin_160_Nov_2014

From ESA Bulletin 160 (page 68)

Quote
LISA PATHFINDER

The Science Module was retrofitted with three new side-panels onto which the cold-gas micro-propulsion equipment had been integrated. Functional verification of the spacecraft is progressing as planned, with the completed version of the flight software and using the FM microthrusters driving electronics. LISA Pathfinder carries two sets of six cold-gas thrusters; the first set is in acceptance testing, whereas the second redundant set is being manufactured. Both the micro-Newton thrust force and thesub-micro-Newton thrust force noise have been confirmed in a dedicated facility by Onera (FR).

Acceptance testing of the two FM Inertial Sensor Heads (ISH) has been completed. The testing campaign included bi-polar discharge of the test mass by means of ultraviolet light, contacting, photoelectric effect. In orbit,  though, the discharge process will be without physical contact between the test mass and its surrounding electrodes. Thus, the ground verification requires novel modelling techniques. The ISH FMs will now be integrated on the LISA Pathfinder Core Assembly (LCA). The LCA includes an optical interferometry ultra-stable bench on its support frame, the two ISH, diagnostics equipment and support equipment. The LCA integration has advanced to the point where the next step is the integration of the ISH.

The launch vehicle will be Vega, on one of the VERTA launches. The lessons learnt from the first Vega launches are being closely monitored to confirm the compatibility with the mission and spacecraft. Considering the approaching launch date, activities by the launcher authority, ESAC and ESOC are running at full pace.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 03/02/2015 11:26 am
Lisa Pathfinder: 'Exquisite' gravity probe leaves UK

http://www.bbc.com/news/science-environment-31642215
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 03/12/2015 08:30 am
Optical bench of LISA Pathfinder

An intimate view of a key part of the payload of ESA’s LISA Pathfinder satellite, which will be the ‘stillest’ ever flown in space – in fact, the distant-orbiting spacecraft is set to become the single most stable place in the Solar System.

These transparent ‘gravestones’ are made of fused silica glass, used to split then recombine a pair of laser beams. The glass elements are aligned down to a few thousands of a millimetre onto the supporting optical bench, made from ultra-low expansion Zerodur glass.

This laser system will measure the very slightest movements of a pair of gold–platinum test masses, right down to subatomic scale precision.

One test mass is placed inside a ‘capacitive sensing’ housing within the cylinder behind the optical bench, visible in the picture, and the other will be in an identical cylinder due to be placed ahead of it.

In space, these test masses will float freely within the spacecraft, which will manoeuvre itself to keep them away from the housing walls.

The aim is to allow the test masses to be subject only to the underlying force of gravity, mapping the very slight curvature of local space-time.

When LISA Pathfinder is launched on a Vega rocket at the end of September, it will fly more than 1.5 million km from Earth to orbit the first Sun–Earth Lagrange Point (L1).

This position will enable the spacecraft to minimise the effects of external perturbations. In addition, the spacecraft itself actively compensates for other forces acting upon it – even firing micronewton thrusters to compensate for the tiny but significant ‘push’ of sunshine.

The optical bench seen here was developed for ESA by the University of Glasgow and University of Birmingham in the UK. The cylinder containing the test mass was developed by CGS in Milano and the integration is now taking place at Airbus Defence and Space in Friedrichshafen, Germany.

LISA Pathfinder is intended to prove the technologies needed for an even more ambitious mission in future: a laser-linked multispacecraft constellation to observe gravitational waves in space.

http://www.esa.int/spaceinimages/Images/2015/03/Optical_bench_of_LISA_Pathfinder

Image credit: Airbus Defence and Space
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: jacqmans on 06/16/2015 01:34 pm
Listening to the 'sound' of the Universe – highly sensitive core of LISA Pathfinder completed
 
16 June 2015

After more than 10 years of intense development, Airbus in Friedrichshafen has completed the main component that will be at the heart of the highly sensitive payload of the LISA Pathfinder mission – the LISA Technology Package (LTP) Core Assembly. The German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) is supporting LISA Pathfinder within the framework of the European Space Agency (ESA) Science Programme. The mission, to be launched in October this year, is designed to validate important technologies whose function and performance capabilities cannot be tested here on Earth, or where only partial testing would be possible on the ground. This mission will pave the way for the Evolved Laser Interferometer Space Antenna (eLISA) gravitational wave observatory that, after its scheduled launch in 2034, will track down the highest-energy and most violent astrophysical events unfolding across the Universe.

Tuning into the 'sound' of the universe

If a stone is dropped in water, oscillations spread in waves across the surface of the water from the point of impact. Like stones falling into water, substantial masses that move through space extremely quickly and with rapidly changing acceleration also produce waves. These propagate through space and inevitably announce their presence as very small oscillations in space-time. These gravitational waves – predicted by the German physicist Albert Einstein in his Theory of General Relativity as far back as 1916 – allow us to 'listen to the sound' of the Universe, opening a new and unobstructed window to observe exotic celestial objects.

Among these are supernovae, close binary star systems consisting of white dwarfs, collisions between neutron stars and pulsars or black hole collisions during galaxy mergers. In the core of galaxies, objects such as white dwarfs, neutron stars or black holes, may travel towards the super massive black hole at the centre; if they get close enough, they will start to spiral in as their orbits shrink as a result of the loss of energy and angular momentum carried away by gravitational waves (extreme-mass-ratio inspirals). Gravitational waves from the time immediately after the Big Bang can reveal more about the origin of the Universe. However, Einstein was somewhat doubtful that gravitational waves would ever be detected, as their effects are extremely small; it has not been possible to measure them so far. But today – almost 100 years after Einstein's prediction, mankind is on the verge of making their 'extremely quiet' oscillations 'audible'. It is expected that proof will be furnished in the coming years – initially using ground-based systems, and subsequently with eLISA out in space.

LISA Pathfinder prepares the way for eLISA

The eLISA space observatory will consist of three spacecraft – a mother craft and two daughter craft. They will be positioned in a near-equilateral triangle formation, with each side measuring approximately two million kilometres. The entire triangle will rotate and follow Earth on its orbit around the Sun at distances ranging between 10 and 25 million kilometres. The spacecraft are connected by laser beams – a feat of unprecedented technical precision. The observatory will be able to 'hear' any gravitational waves that pass through their alignment in a frequency range of between 0.1 millihertz and 0.1 hertz. The necessary technology requires initial testing in space, as the mission is extremely complex and involves components that cannot be tested adequately on the ground.

LISA Pathfinder will handle this task. The components used in the scientific payload – the LTP – were developed by several European countries and put together to form a composite payload by Airbus Defence & Space in Friedrichshafen. DLR played a key role in the development of the payload within the framework of the ESA Science Programme. Here, the German contribution received a substantial boost from a grant awarded by the DLR Space Administration to the Max Planck Institute for Gravitational Physics (Albert Einstein Institute) in Hannover.

Highly sensitive measurement system

The LTP control electronics in the LISA Pathfinder orbiter have been installed and tested, and the final and most important unit in the payload, the LTP Core Assembly, will follow shortly. Its construction is now complete, and the unit has been sent from Friedrichshafen to IABG in Munich for integration into the spacecraft and final testing.

During the mission, two identical cube-shaped test masses, each weighing two kilograms, will be suspended in their own LTP vacuum vessel, almost free of internal and external disturbances, hence demonstrating free flight in space. A special gold-platinum alloy has been used for the masses, ensuring that magnetic forces do not have any effect. Using ultraviolet radiation, a contactless discharge system prevents any electrostatic charging of the masses. The caging and venting mechanism – responsible for protecting the test masses from intense vibrations during launch, releasing them in a highly controlled setting, and capturing them as necessary – is a particular challenge in this context. The laser interferometer will measure the position and orientation of the two test masses relative to the spacecraft and to each other at a precision of approximately one hundred millionth of a millimetre. In addition, there are other, less precise, sensors that also help determine their positions. A Drag-Free Attitude Control System (DFACS) uses the measurement data to control the spacecraft and to ensure it always remains centred on the test masses. Cold gas micronewton thrusters developed for the Gaia astrometry mission, which have the capability of delivering propulsion in extremely fine and uniform amounts, will control the position of the spacecraft.

The mission is scheduled for launch in October 2015. A one-year period of operation in an orbit around L2, approximately 1.5 million kilometres behind Earth when viewed from the Sun, will follow after launch. The Lagrangian points, named after Joseph-Louis Lagrange, are positions in which a gravitational state of equilibrium occurs, meaning that (in ideal cases), a spacecraft can 'linger' there.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 06/26/2015 01:42 pm
LISA Pathfinder science module during tests

The LISA Pathfinder science module pictured in a cleanroom at IABG, Ottobrunn, Germany, in June 2015. One of two (gold coloured) colloidal micro-Newton thrusters, part of the NASA provided Space Technology 7 mission, can be seen on the side of the spacecraft.

http://sci.esa.int/lisa-pathfinder/56042-lisa-pathfinder-science-module-during-tests/

Related article:

- LISA Pathfinder prepares for final exams

http://sci.esa.int/lisa-pathfinder/55970-lisa-pathfinder-prepares-for-final-exams/

Credit: ESA - P. McNamara
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: catdlr on 07/17/2015 07:40 pm
ESA Euronews: The quest to capture gravitational waves

Published on Jul 17, 2015
The LISA Pathfinder spacecraft is due to set off in Autumn 2015 in a bid to prove that it is possible to observe gravitational waves in space. This is the latest step in an incredible journey to spot these ripples in spacetime that were first predicted by Albert Einstein 100 years ago.

https://youtu.be/PFHOeNOQ9DE
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: catdlr on 07/17/2015 07:43 pm
Inside LISA Pathfinder

Published on Jul 17, 2015
ESA’s LISA Pathfinder mission is a technology demonstrator that will pave the way for future spaceborne gravitational-wave observatories. It will operate about 1.5 million km from Earth towards the Sun, orbiting the first Sun–Earth ‘Lagrangian point’, L1.


https://youtu.be/YyZJ1JC_URc
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 07/20/2015 01:50 pm
LISA Pathfinder with Vega launch vehicle adapter

LISA Pathfinder launch composite on the Vega launch vehicle adapter, at IABG, Ottobrunn, Germany.

The launch composite with the octagonal-shaped science module and the silver-coloured propulsion module, is the configuration in which the spacecraft will be launched.

The red conical structure at the base of the propulsion module is the main engine nozzle, a 400 Newton class liquid apogee engine (LAE) providing the impulses for the major delta-V manoeuvres.

The launch vehicle adapter – the black conical structure under the launch composite – is the fixture by which the spacecraft is mounted on the launcher.

http://sci.esa.int/lisa-pathfinder/56027-lisa-pathfinder-with-vega-launch-vehicle-adapter/

Related article:

- LISA Pathfinder prepares for the Vega launcher

http://sci.esa.int/lisa-pathfinder/56163-lisa-pathfinder-prepares-for-the-vega-launcher/

Image credit: ESA – U. Ragnit
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 08/26/2015 09:26 am
ESA BR-323: LISA Pathfinder (Brochure)

http://sci.esa.int/lisa-pathfinder/56377-esa-br-323-lisa-pathfinder/
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 09/01/2015 01:45 pm
LISA Pathfinder set for launch site

1 September 2015

LISA Pathfinder, ESA’s demonstrator for spaceborne observations of gravitational waves, is ready to leave for Europe’s Spaceport in Kourou, French Guiana.

Scheduled for launch on a Vega rocket later this year, the spacecraft was on display today at IABG’s test centre in Ottobrunn, near Munich, Germany, where final integration and extensive tests were performed over the past few months.

This was the last chance for scientists, engineers and members of the media to see LISA Pathfinder before it is packed for shipping.

http://www.esa.int/Our_Activities/Space_Science/LISA_Pathfinder_set_for_launch_site

Image credit: ESA–P. Sebirot, 2015
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 09/01/2015 01:47 pm
Launch topic here:

- http://forum.nasaspaceflight.com/index.php?topic=38145.0
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: jacqmans on 12/07/2015 12:29 pm
LISA Pathfinder star tracker image
 

A portion of the Earth during night time, covered by layers of the atmosphere, as seen through LISA Pathfinder's star trackers on 3 December 2015. Beyond the horizon of our planet, several stars are visible, above as well as through the atmosphere.
 
LISA Pathfinder, ESA's mission to test technology for gravitational wave detection in space, blasted off on 3 December at 04:04 GMT (05:04 CET). The Vega rocket delivered it to a low-Earth parking orbit and, from there, the satellite will perform a series of six critical burns to raise the highest point of the orbit. Eventually, it will reach its operational orbit around the Lagrange point L1, 1.5 million km away from Earth towards the Sun.
 
Since taking over control of the spacecraft after it separated from the upper stage of the Vega launcher, the mission control teams at ESA’s European Space Operations Centre in Darmstadt, Germany, have been checking that various subsystems on board LISA Pathfinder are working well ahead of the critical orbit raising phase. Among these operations, they also tested the two star-tracker cameras, located below the science module, that are used for navigating the satellite using the stars as reference points.
 
During the science mission, the images taken by the star-trackers are not sent to Earth but processed on board. However, during the commissioning of the spacecraft, the operators are collecting data from the star-trackers, and so obtained a one-of-a-kind image – at least for a non-imaging satellite such as LISA Pathfinder.
 
Acknowledgement: this image was prepared by Jonathan Grzymisch (LISA Pathfinder Control Engineer at ESA) and Mark Watt (Airbus-DS).
 
Credit: ESA/LPF/Airbus-DS; Acknowledgement to J. Grzymisch & M. Watt
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 12/23/2015 09:09 am
http://blogs.esa.int/rocketscience/2015/12/14/en-route-to-nothing/

https://youtu.be/maKX1OFfpXw
Title: ESA/NASA - LISA Pathfinder updates
Post by: Star One on 01/12/2016 09:36 am
Looking increasingly likely that in any race to discover Gravitational waves that this whole undertaking will be well beaten by Advanced LIGO if results pan out.

http://gizmodo.com/rumors-are-flying-that-we-may-have-finally-found-gravit-1752259868
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: Alpha_Centauri on 01/12/2016 12:45 pm
Just a rumour so far, but even if the team believes they might have found something it could be a blind injection test; http://www.ligo.org/news/blind-injection.php , wouldn't know til the last minute.

Besides, LISA/eLISA/whatever is not hinged on being the first to directly confirm gravitational waves. LISA was designed to be complementary to the ground-based experiments as it will be able to see the arguably more interesting low frequency waves that they cannot and with better precision, many more sources, and better source identification. LISA is more like an observatory rather than a lab experiment.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: woods170 on 01/12/2016 01:14 pm
Looking increasingly likely that in any race to discover Gravitational waves that this whole undertaking will be well beaten by Advanced LIGO if results pan out.

http://gizmodo.com/rumors-are-flying-that-we-may-have-finally-found-gravit-1752259868

A. There is no such race.
B. The chances of Advanced LIGO indeed having observed gravitational waves is estimated (as quoted in the article) to be 15 percent at most.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: Star One on 01/12/2016 03:10 pm

Looking increasingly likely that in any race to discover Gravitational waves that this whole undertaking will be well beaten by Advanced LIGO if results pan out.

http://gizmodo.com/rumors-are-flying-that-we-may-have-finally-found-gravit-1752259868

A. There is no such race.
B. The chances of Advanced LIGO indeed having observed gravitational waves is estimated (as quoted in the article) to be 15 percent at most.

A. Of course there is a race, there's always a race for new discoveries like this.

B. Doesn't mean that they haven't discovered something.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: Jester on 01/13/2016 09:31 am
Laser has been switched on successfully.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: Lillmalen on 01/22/2016 03:57 pm
Successful separation

https://twitter.com/hashtag/LISAPathfinder?src=hashl
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: plutogno on 01/23/2016 06:59 am
what happens next to the spent propulsion stage? solar orbit or a distant Earth orbit?
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: russianhalo117 on 01/23/2016 11:44 pm
what happens next to the spent propulsion stage? solar orbit or a distant Earth orbit?
It continues on an orbit past L1 around the sun like the Stereo SC's
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: as58 on 02/05/2016 03:17 pm
Not directly related to LISA Pathfinder or spaceflight at all, but rumours about Advanced LIGO detection are getting stronger and more specific. Supposedly, the announcement will be next week (Thursday?).
Title: ESA/NASA - LISA Pathfinder updates
Post by: Star One on 02/05/2016 07:07 pm
Not directly related to LISA Pathfinder or spaceflight at all, but rumours about Advanced LIGO detection are getting stronger and more specific. Supposedly, the announcement will be next week (Thursday?).

There's a dedicated thread somewhere in here you might want to post that in.:)
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 02/06/2016 01:47 pm
First locks released from LISA Pathfinder's cubes

03 February 2016

Today, the lock fingers that kept the two test masses on LISA Pathfinder secure during the launch and cruise phase were successfully unlocked. As planned, the two cubes are still attached to the spacecraft via an additional mechanism that will hold them in place until mid February, as the teams carry on with the spacecraft and payload commissioning.

http://sci.esa.int/lisa-pathfinder/57290-first-locks-released-from-lisa-pathfinders-cubes/

Image credit: ESA/ATG medialab
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: eeergo on 02/15/2016 07:23 am
Quote from: @ESA_LPF 1h ago
The team are getting ready for the first test mass release #GOLPF

Quote from: @ESA_LPF 1m ago
Test mass 2 is free and under control. Many happy faces in the PISA!! #GOLPF
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 02/16/2016 11:13 am
Freely Floating in space

At the core of LISA Pathfinder are the two test masses: a pair of identical 46 mm gold–platinum cubes, floating freely, several millimetres from the walls of their housings. The cubes are separated by 38 cm and linked only by laser beams to measure their position continuously.

During the science operations phase, microthrusters will make minuscule shifts in order to keep the spacecraft centred on one of the masses. This will isolate the two cubes from all external and internal forces except gravity, placing them in the most precise freefall ever obtained.

Related article: Test cubes floating freely inside LISA Pathfinder (http://www.esa.int/Our_Activities/Space_Science/Test_cubes_floating_freely_inside_LISA_Pathfinder)

http://www.esa.int/spaceinimages/Images/2016/02/Freely_Floating_in_space

Image credit: ESA/ATG medialab
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: Satt on 02/16/2016 09:44 pm
Fantastic, amazing, mind boggling science and engineering.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: eeergo on 02/24/2016 03:17 pm
http://www.esa.int/Our_Activities/Space_Science/Freefall_achieved_on_LISA_Pathfinder

On the 19th, a brief test of drag-free conditions was achieved, applying no electrostatic potential along the cubes' sensitive axes to control their position. From two days ago, the spacecraft is being maneuvered around the cubes, keeping it centered around one. Next week, final science operations will begin.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: eeergo on 03/01/2016 08:54 am
Science mode started as scheduled !


Quote from: @ESA_LPF
2016-03-01 08:00:00UTC.....Science Operations have started!
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 03/08/2016 06:28 pm
http://www.esa.int/Our_Activities/Space_Science/A_perfectly_still_laboratory_in_space

Quote
LISA Pathfinder, however, is not capable of detecting gravitational waves itself. For this crucial technology demonstration, the two freefalling cubes are only 38 cm apart – too close to record the minute wobbles in the fabric of spacetime.

The variation in distance caused by a passing gravitational wave is so small that a full-scale space observatory will need test masses separated by roughly a million kilometres, and be able to detect changes in that separation of about one millionth of a millionth of a metre.

“The precision we need to attain for future observations of gravitational waves from space is so high that it demands an unprecedented understanding of the physical forces at play on the test masses,” says Paul McNamara, ESA’s Project Scientist.

Quote
“We are looking forward to demonstrating this thruster system and its ability to keep the two test masses extremely still,” says Charles Dunn, project technologist for the DRS at JPL.

The results of LISA Pathfinder's precision experiments will pave the way towards the L3 mission in ESA’s Cosmic Vision programme, a future project that will be dedicated to investigating the gravitational Universe by means of a large spaceborne observatory.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: Star One on 04/18/2016 07:22 pm
GOAT has given the thumbs up to LISA & even called for its launch to be brought forward by five years to 2029.

http://www.bbc.co.uk/news/science-environment-36068599
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: jacqmans on 05/24/2016 01:20 pm
Press Release
N°19-2016

Paris, 25 May 2016

Call for Media: First results from ESA's LISA Pathfinder mission

Media representatives are invited to a briefing on the first results from ESA's LISA Pathfinder mission, a technology demonstrator for the observation of gravitational waves from space.

The media briefing is being organised by the European Space Agency at the European Space Astronomy Centre (ESAC) in Villanueva de la Cañada, Madrid, Spain, on Tuesday, 7 June, 11:30-13:00 CEST. Doors open at 11:00 CEST [times TBC].

Launched in December 2015, LISA Pathfinder travelled to its operational orbit, 1.5 million km from Earth towards the Sun, where it started its scientific mission on 1 March. At the core of the spacecraft, two identical gold-platinum cubes, are being
held in the most precise freefall ever produced in space.

Placing the test masses in a motion subject only to gravity is the challenging condition needed to build and operate a future space mission to observe gravitational waves. Predicted by Albert Einstein a century ago, gravitational waves are fluctuations
in the fabric of spacetime, which were recently detected directly for the first time by the Laser Interferometer Gravitational-Wave Observatory. 

Over the first two months of scientific operations, the LISA Pathfinder team has performed a number of experiments on the test masses to prove the feasibility of gravitational wave observation from space. These results will be presented at the media
briefing.

Programme outline

11:30-11:40 - Fabio Favata, Head of the Coordination Office, ESA Directorate of Science

Opening up the gravitational Universe for ESA's Science Programme 

11:40-11:50 - Paul McNamara, ESA LISA Pathfinder Project Scientist
- LISA Pathfinder: A new way to look at our Universe

11:50-12:00 - Martin Hewitson, LISA Pathfinder Deputy Primary Investigator, University of Hanover
- LISA Pathfinder optical metrology performance

12:00-12:10 - Stefano Vitale, LISA Pathfinder Primary Investigator, University of Trento
- LISA Pathfinder first results

12:10-13:00 - Question and Answer sessions and opportunity for individual interviews


Attending

For accreditation, media can register at: 

https://myconvento.com/public/event_register/index/1351840

Please register by 6 June at 12:00 CEST.

How to get to ESAC: http://www.esa.int/About_Us/ESAC/Getting_to_ESAC

Follow online

Webstreaming

Livestream.com/esa

Social media

Twitter: @esascience and @ESA_LPF, hashtag #LisaPathfinder 

Reddit: an AMA (Ask Me Anything) session with mission experts on the reddit social media platform, where users may ask all kinds of questions, will be conducted from 16:00 to 17:00 CEST (14:00 to 15:00 GMT) on 7 June at https://www.reddit.com/r/IAmA

Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: plutogno on 06/07/2016 10:42 am
LISA Pathfinder Exceeds Expectations
http://www.esa.int/Our_Activities/Space_Science/LISA_Pathfinder_exceeds_expectations
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: jebbo on 06/07/2016 02:02 pm
LISA Pathfinder IamA reddit: https://www.reddit.com/r/IAmA/comments/4myjs7/we_are_scientists_from_the_lisa_pathfinder/

--- Tony
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 06/07/2016 02:42 pm
LISA Pathfinder Exceeds Expectations
http://www.esa.int/Our_Activities/Space_Science/LISA_Pathfinder_exceeds_expectations

Image credit: Spacecraft: ESA/ATG medialab; data: ESA/LISA Pathfinder Collaboration
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 06/07/2016 02:43 pm
LISA Pathfinder first results media briefing (video)

http://www.esa.int/spaceinvideos/Videos/2016/06/LISA_Pathfinder_first_results_media_briefing
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: Star One on 06/07/2016 05:16 pm
Lisa Pathfinder’s success boosts likelihood of future gravity-wave observatory

Quote
The 22-nation European Space Agency has said a laser-interferometry mission featuring three spacecraft millions of kilometers apart and linked by lasers is their preferred next selection for Large-class mission.

But while Lisa Pathfinder’s ability to eliminate most surrounding noise, including that caused by gas molecules, during its nearly three months of operations argues heavily in favor of a full-blown Lisa mission, other technologies need to be proven before the full observatory is given go-ahead approval.

Quote
Asked whether a national 2034 date could not be moved forward by five years, to 2029, Favata said the technologies challenges remaining are probably too formidable to make the earlier date.

Favata said ESA will spend the next three or four years examining how close they are to reaching the technology readiness level for the Lisa mission components. Once a go-ahead is decided, a 10-year development effort would begin.

Quote
Favata said ESA expects NASA will also be a partner on the full Lisa observatory for 2034. Details are yet to be finalized. ESA’s Large-class missions are budgeted at aroun 900 million euros, plus whatever contributions are made by national European laboratories and national space agencies in Europe.

http://spacenews.com/lisa-pathfinders-success-boosts-likelihood-of-future-gravity-wave-observatory/
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: catdlr on 06/07/2016 08:55 pm
LISA Pathfinder’s Stunning Success

NASA Goddard

Published on Jun 7, 2016
LISA Pathfinder, a mission led by the European Space Agency (ESA) with contributions from NASA, has successfully tested a key technology needed to build a space-based observatory for detecting gravitational waves. These tiny ripples in the fabric of space, predicted by Albert Einstein a century ago, were first seen last year by the ground-based Laser Interferometer Gravitational-Wave Observatory (LIGO).

Seismic, thermal, and other noise sources limit LIGO to higher-frequency gravitational waves around 100 cycles per second (hertz). But finding signals from more exotic events, such as mergers of supermassive black holes in colliding galaxies, requires the ability to see frequencies at 1 hertz or less, a sensitivity level only possible from space.

A space-based observatory would work by tracking test masses that move only under the influence of gravity. Each spacecraft would gently fly around its test masses without disturbing them, a process called drag-free flight. The primary goal of ESA's LISA Pathfinder mission is to test current technology by flying around an identical pair of 1.8-inch (46 millimeter) cubes made of a gold-platinum alloy, a material chosen for its high density and insensitivity to magnetic fields.

Scientists say the results are nothing short of astonishing. Non-gravitational forces on the cubes were reduced to levels far below the project's original requirements and approach the level of control needed for a full-scale observatory.

The test masses are housed in an experiment called the LISA Technology Package (LTP), which was built by a consortium of European national space agencies and ESA. The LTP uses a high-resolution laser interferometer to determine the positions of the test masses and relays the information to the spacecraft's Drag-Free and Attitude Control System, which then applies minute bursts from microthrusters. In this way, the spacecraft flies in formation with the cubes and isolates them from external forces. The results show that LISA Pathfinder reduced non-gravitational forces on the test masses to a level about 10,000 times smaller than drag-free control technologies used on previous science missions.

LISA Pathfinder also carries a NASA experiment called the ST-7 Disturbance Reduction System which is expected to begin science operations in early July.

LISA Pathfinder was launched on Dec. 3, 2015, and began orbiting a point called Earth-sun L1, roughly 930,000 miles (1.5 million kilometers) from Earth in the sun's direction, in late January 2016. LISA stands for Laser Interferometer Space Antenna, a space-based gravitational wave observatory concept that has been studied in great detail by both NASA and ESA. The LISA Pathfinder mission is an ESA-led effort to demonstrate technologies for a future gravitational wave observatory in space. NASA Goddard astrophysicist Ira Thorpe, a member of the team, discusses the mission and its spectacular results so far.

Credit: NASA's Goddard Space Flight Center/Scott Wiessenger

This video is public domain and along with other supporting visualizations can be downloaded from the Scientific Visualization Studio at: http://svs.gsfc.nasa.gov/12264

If you liked this video, subscribe to the NASA Goddard YouTube channel: http://www.youtube.com/NASAExplorer


https://youtu.be/TsgfnkSJdqs?t=001

https://youtu.be/TsgfnkSJdqs
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: catdlr on 06/07/2016 08:56 pm
LISA Pathfinder results

European Space Agency, ESA

Published on Jun 7, 2016
Launched in December 2015, LISA Pathfinder travelled to its operational orbit, 1.5 million km from earth towards the Sun, where it started its scientific mission on 1 March.

https://youtu.be/P4a0hXobXlo?t=001

https://youtu.be/P4a0hXobXlo
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: Star One on 06/07/2016 09:32 pm
The first videos in the above two posts are both showing 400 error?
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: catdlr on 06/07/2016 10:04 pm
The first videos in the above two posts are both showing 400 error?

I'm able to play the embedded and linked videos.  Might be YouTube cached server issues with your region?
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: russianhalo117 on 06/08/2016 12:49 am
The first videos in the above two posts are both showing 400 error?
they work for me
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: Star One on 06/08/2016 05:54 am
The first videos in the above two posts are both showing 400 error?
they work for me

They are both working now, odd.
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 06/28/2016 09:00 am
LISA pathfinder completes first operations phase

24 June 2016

On Saturday 25 June, the LISA Technology Package (LTP) – a European payload on ESA's LISA Pathfinder – completes its nominal operations phase, passing the baton to the Disturbance Reduction System, an additional experiment provided by NASA. This won't be the last time the European experiment is run – the recently approved mission extension will see the LTP back in action for seven months starting in November this year.

http://sci.esa.int/lisa-pathfinder/58006-lisa-pathfinder-completes-first-operations-phase/

Image credit:  ESA/LISA Pathfinder Collaboration
Title: Re: ESA/NASA - LISA Pathfinder updates
Post by: bolun on 07/17/2016 08:11 pm
http://english.nssc.cas.cn/ns/headline/201605/t20160518_163197.html

The 12th China-ESA Space Science Bilateral Meeting Opens in Shanghai

Quote
... both parties introduced the respective gravitational wave detection plans and agreed that there is a cooperation possibility in this area.
Title: Re: LISA Pathfinder updates
Post by: Sam Ho on 08/16/2016 03:56 pm
The National Academies published a midterm assessment of the New Worlds, New Horizons program.

http://www.nap.edu/23560

The assessment bemoans the gutting of gravitational wave funding after the cancellation of LISA, and recommends that the US provide support to bring eLISA back up to the capabilities LISA had.

Quote
FINDING 4-9: The dissolution of the U.S. LISA project, and the attendant loss of science and technology funding, has severely impacted preparations for a space gravitational wave mission. If this situation persists, the options for significant U.S. participation in this revolutionary discovery area will be limited.

Quote
RECOMMENDATION 4-4: NASA should restore support this decade for gravitational wave research that enables the U.S. community to be a strong technical and scientific partner in the European Space Agency (ESA)-led L3 mission, consistent with LISA’s high priority in the 2010 report New Worlds, New Horizons in Astronomy and Astrophysics (NWNH). One goal of U.S. participation should be the restoration of the full scientific capability of the mission as envisioned by NWNH.
Title: Re: LISA Pathfinder updates
Post by: eeergo on 08/16/2016 05:46 pm
The 3Cat-2 satellite orbited yesterday by China carries a demonstrator for the eLISA magnetometer (AMR):

https://nanosatlab.upc.edu/en/missions-and-projects/3cat-2
Title: Re: LISA Pathfinder updates
Post by: Star One on 09/12/2016 06:26 am
NASA moves to rejoin sped-up gravitational wave mission

Quote
This week, at the 11th LISA symposium in Zürich, Switzerland, a NASA official said he was ready to rejoin the LISA mission, which the agency left in 2011. Meanwhile, ESA says it is trying to move the launch of the mission up several years from 2034. “This is a very important meeting,” says David Shoemaker, a gravitational wave physicist at the Massachusetts Institute of Technology in Cambridge. “It feels like a turning point.”

http://www.sciencemag.org/news/2016/09/nasa-moves-rejoin-sped-gravitational-wave-mission
Title: Re: LISA Pathfinder updates
Post by: baldusi on 09/12/2016 05:03 pm
NASA moves to rejoin sped-up gravitational wave mission

Quote
This week, at the 11th LISA symposium in Zürich, Switzerland, a NASA official said he was ready to rejoin the LISA mission, which the agency left in 2011. Meanwhile, ESA says it is trying to move the launch of the mission up several years from 2034. “This is a very important meeting,” says David Shoemaker, a gravitational wave physicist at the Massachusetts Institute of Technology in Cambridge. “It feels like a turning point.”

http://www.sciencemag.org/news/2016/09/nasa-moves-rejoin-sped-gravitational-wave-mission
I truly hope this time NASA keeps its word support.
Title: Re: LISA Pathfinder updates
Post by: Star One on 09/12/2016 05:14 pm
NASA moves to rejoin sped-up gravitational wave mission

Quote
This week, at the 11th LISA symposium in Zürich, Switzerland, a NASA official said he was ready to rejoin the LISA mission, which the agency left in 2011. Meanwhile, ESA says it is trying to move the launch of the mission up several years from 2034. “This is a very important meeting,” says David Shoemaker, a gravitational wave physicist at the Massachusetts Institute of Technology in Cambridge. “It feels like a turning point.”

http://www.sciencemag.org/news/2016/09/nasa-moves-rejoin-sped-gravitational-wave-mission
I truly hope this time NASA keeps its word support.

Unfortunately it doesn't look like they are going to put the $1 billion promised previously, but at least it should be higher than the current $150 million.
Title: Re: ESA - LISA Pathfinder updates
Post by: bolun on 10/07/2016 01:36 pm
The LISA Pathfinder science archive is online

07 October 2016

Today, ESA's LISA Pathfinder Science Archive opens its virtual gates to the world. It contains data collected by the satellite during the mission's first few months, covering the nominal operations phase of the LISA Technology Package (LTP) – the European payload on LISA Pathfinder.

- Link: LISA Pathfinder Legacy Archive (http://lpf.esac.esa.int/lpfsa/)

http://sci.esa.int/lisa-pathfinder/58410-the-lisa-pathfinder-science-archive-is-online/
Title: Re: ESA - LISA Pathfinder updates
Post by: bolun on 12/13/2016 08:01 pm
http://sci.esa.int/lisa-pathfinder/58633-lisa-pathfinder-s-pioneering-mission-continues/

LISA Pathfinder's pioneering mission continues

Quote
On 7 December, LISA Pathfinder started the extended phase of its mission, an additional six months during which scientists and engineers will push the experiment to its limits in preparation for ESA's future space observatory of gravitational waves.

Quote
..., on 25 June, the first operations phase, using the LISA Technology Package (LTP), was completed. The LTP is a European payload consisting of the test masses, inertial sensors, and laser interferometer, and uses a series of cold-gas micronewton thrusters to move the satellite and keep it centred on the cubes, in response to external and internal forces battering them around.

Operations continued with NASA's Disturbance Reduction System (DRS), an additional experiment which receives measurement input from the inertial sensors of the LTP but employs its own micronewton thrusters based on colloidal technology.

Following completion of the DRS operations, the extended mission of LISA Pathfinder began on 7 December 2016, at 09:00 CET (08:00 UTC). It will last until 31 May 2017, making use of both the LTP and DRS payloads.
Title: ESA - LISA Pathfinder updates
Post by: Star One on 01/29/2017 07:27 pm
Quote
Jeff Foust –  ‏@jeff_foust

Shoemaker: goal of LISA tech dev work is to enable earliest possible launch date: as soon as 2029, depending on budget. #apsapril

https://mobile.twitter.com/jeff_foust/status/825798201294807044

Quote
Jeff Foust –  ‏@jeff_foust

David Shoemaker, MIT: proposal to ESA for LISA assumes a 20% NASA contribution; max allowed by ESA. #apsapril

https://mobile.twitter.com/jeff_foust/status/825796636471275520

Quote
Jeff Foust –  ‏@jeff_foust

Paul McNamara, ESA: LISA Pathfinder end of mission planned for April with maneuver to drift spacecraft away from Earth-Sun L1. #apsapril

https://mobile.twitter.com/jeff_foust/status/825784992470929408
Title: ESA - LISA Pathfinder updates
Post by: Star One on 02/07/2017 04:23 pm
Scientists optimistic about prospects for LISA gravitational wave mission

Quote
A European consortium submitted to ESA in January a proposal for the development of the Laser Interferometer Space Antenna (LISA) mission for ESA’s third large mission, or L3, competition. LISA is widely considered the leading candidate to be selected for that mission for launch likely in the early 2030s.

LISA, as proposed, will consist of three spacecraft in a triangular formation, each 2.5 million kilometers from the other two in an orbit around the sun trailing the Earth. The spacecraft would shine lasers at each other, with interferometers on each spacecraft detecting minute distance changes caused by passing gravitational waves.

The three spacecraft, with a combined mass of about 6,000 kilograms, including payload adapter, would launch on an Ariane 6 and drift to their planned orbit over the course of a year and a half. LISA would have a planned mission lifetime of four years, but with sufficient propellant on each spacecraft to operate for up to a decade.

“LISA looks like it’s going to happen. It looks like it’s on a pretty firm track,” said David Shoemaker, a senior research scientist at the Massachusetts Institute of Technology’s Kavli Institute for Astrophysics and Space Research, during a meeting of the American Physical Society (APS) here Jan. 29.

Shoemaker is chairman of the L3 Study Team, a NASA group looking at contributions NASA can make to the LISA mission. The LISA proposal submitted to ESA assumes NASA will cover 20 percent of the mission’s cost through instruments and other technologies.

Parth of the confidence of Shoemaker and other scientists is linked to the announcement a year ago of the first detection of gravitational waves, by the Laser Interferometer Gravitational-Wave Observatory (LIGO), ground-based gravitational wave detectors in Louisiana and Washington. That discovery removed any doubt that gravitational waves exist, creating confidence that a mission like LISA could also successfully detect and study gravitational waves, and do so at frequencies not possible with LIGO.

Another factor is the technical success of ESA’s LISA Pathfinder mission, a single small spacecraft launched in December 2015 to test technologies that could be used in a later LISA mission. The performance of the spacecraft, including a thruster system provided by NASA, exceeded expectations.

Those tests not only exceeded the stability expectations of the LISA Pathfinder mission, but also approached the requirements for the full-fledged LISA mission. “This was a successful demonstration of drag-free control at a level necessary for a LISA-type gravitational wave observatory,” said Charles Dunn of JPL, project technologist for the disturbance reduction system flown on LISA Pathfinder, at the APS meeting Jan. 28.

- See more at: http://spacenews.com/scientists-optimistic-about-prospects-for-lisa-gravitational-wave-mission/#sthash.dcogrTj4.dpuf
Title: Re: ESA - LISA Pathfinder updates
Post by: Star One on 04/17/2017 08:03 pm
NASA Team Explores Using LISA Pathfinder as 'Comet Crumb' Detector
LISA Pathfinder, a mission led by ESA (the European Space Agency) with contributions from NASA, has successfully demonstrated critical technologies needed to build a space-based observatory for detecting ripples in space-time called gravitational waves. Now a team of NASA scientists hopes to take advantage of the spacecraft's record-breaking sensitivity to map out the distribution of tiny dust particles shed by asteroids and comets far from Earth.

Most of these particles have masses measured in micrograms, similar to a small grain of sand. But with speeds greater than 22,000 mph (36,000 kph), even micrometeoroids pack a punch. The new measurements could help refine dust models used by researchers in a variety of studies, from understanding the physics of planet formation to estimating impact risks for current and future spacecraft.


In a proof-of-concept study, NASA scientists are exploring using ESA’s (the European Space Agency) LISA Pathfinder spacecraft as a micrometeoroid detector. When tiny particles shed by asteroids and comets impact LISA Pathfinder, its thrusters work to quickly counteract any change in the spacecraft's motion. Researchers are monitoring these signals to learn more about the impacting particles.
Credits: NASA's Goddard Space Flight Center
Download HD video and additional visuals from NASA's Scientific Visualization Studio
"We've shown we have a novel technique and that it works," said Ira Thorpe, who leads the team at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The next step is to carefully apply this technique to our whole data set and interpret the results."

The mission's primary goal was to test how well the spacecraft could fly in formation with an identical pair of 1.8-inch (46 millimeter) gold-platinum cubes floating inside it. The cubes are test masses intended to be in free fall and responding only to gravity.

The spacecraft serves as a shield to protect the test masses from external forces. When LISA Pathfinder responds to pressure from sunlight and microscopic dust impacts, the spacecraft automatically compensates by firing tiny bursts from its micronewton thrusters to prevent the test masses from being disturbed.   

Scientists call this drag-free flight. In its first two months of operations in early 2016, LISA Pathfinder demonstrated the process with a precision some five times better than its mission requirements, making it the most sensitive instrument for measuring acceleration yet flown. It has now reached the sensitivity level needed to build a full multi-spacecraft gravitational wave observatory.

"Every time microscopic dust strikes LISA Pathfinder, its thrusters null out the small amount of momentum transferred to the spacecraft," said Goddard co-investigator Diego Janches. "We can turn that around and use the thruster firings to learn more about the impacting particles. One team's noise becomes another team's data."

Much of what we know about interplanetary dust is limited to Earth's neighborhood, thanks in large part to NASA's Long Duration Exposure Facility (LDEF). Launched into Earth orbit by the space shuttle Challenger in April 1984 and retrieved by the space shuttle Columbia in January 1990, LDEF hosted dozens of experiments, many of which were designed to better understand the meteoroid and orbital debris environment.

The different compositions, orbits and histories of different asteroids and comets naturally produce dust with a range of masses and velocities. Scientists suspect the smallest and slowest particles are enhanced in Earth's neighborhood, so the LDEF results are not representative of the wider solar system.

"Small, slow particles near a planet are most susceptible to the planet's gravitational pull, which we call gravitational focusing," Janches said. This means the micrometeoroid flux near Earth should be much higher than that experienced by LISA Pathfinder, located about 930,000 miles (1.5 million kilometers) closer to the sun.

To find the impacts, Tyson Littenberg at NASA's Marshall Space Flight Center in Huntsville, Alabama, adapted an algorithm he originally developed to search for gravitational waves in data from the ground-based detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO), located in Livingston, Louisiana, and Hanford, Washington. In fact, it was one of many algorithms that played a role in the discovery of gravitational waves by LIGO, announced in February 2016.

"The way it works is that we come up with a guess of what the signal might look like, then study how LIGO or LISA Pathfinder would react if this guess were true," Littenberg explained. "For LIGO, we're guessing about the waveform, the peaks and valleys of the gravitational wave. For LISA Pathfinder, we're guessing about an impact."

To map out the probability of likely sources, the team generates millions of different scenarios describing what the source might be and compares them to what the spacecraft actually detects.

In response to an impact, LISA Pathfinder fires its thrusters to counteract both the minute "push" from the strike and any change in the spacecraft's spin. Together, these quantities allow the researchers to determine the impact's location on the spacecraft and reconstruct the micrometeoroid's original trajectory. This may allow the team to identify individual debris streams and perhaps relate them to known asteroids and comets.

"This is a very nice collaboration," said Paul McNamara, the LISA Pathfinder project scientist at ESA's Directorate of Science in Noordwijk, the Netherlands. "This is data we use for doing our science measurements, and as an offshoot of that, Ira and his team can tell us about microparticles hitting the spacecraft."

Its distant location, sensitivity to low-mass particles, and ability to measure the size and direction of impacting particles make LISA Pathfinder a unique instrument for studying the population of micrometeoroids in the inner solar system. But it's only the beginning.

"This is a proof of concept, but we'd hope to repeat this technique with a full gravitational wave observatory that ESA and NASA are currently studying for the future," said Thorpe. "With multiple spacecraft in different orbits and a much longer observing time, the quality of the data should really improve."

LISA Pathfinder is managed by ESA and includes contributions from NASA Goddard and NASA's Jet Propulsion Laboratory in Pasadena, California. The mission launched on Dec. 3, 2015, and began orbiting a point called Earth-sun L1, roughly 930,000 miles (1.5 million km) from Earth in the sun's direction, in late January 2016.

LISA stands for Laser Interferometer Space Antenna, a space-based gravitational wave observatory concept that has been studied in great detail by both NASA and ESA. It is a concept being explored for the third large mission of ESA's Cosmic Vision Plan, which seeks to launch a gravitational wave observatory in 2034.

Banner image: An illustration of LISA Pathfinder on its way to Earth-sun L1. Credit: ESA/C. Carreau

https://www.nasa.gov/feature/goddard/2017/nasa-team-explores-using-lisa-pathfinder-as-comet-crumb-detector
Title: Re: ESA - LISA Pathfinder updates
Post by: bolun on 06/20/2017 08:12 pm
LISA Pathfinder to conclude trailblazing mission

http://sci.esa.int/lisa-pathfinder/59238-lisa-pathfinder-to-conclude-trailblazing-mission/

Quote
After sixteen months of science operations, LISA Pathfinder will complete its mission on 30 June, having successfully demonstrated the technology to build ESA's future space observatory of gravitational waves.

Quote
As LISA Pathfinder approaches the end of its successful technology demonstration mission, ESA's Science Programme Committee has selected today the Laser Interferometer Space Antenna (LISA) as the third large mission (L3) in ESA's Cosmic Vision plan. LISA is a space-based observatory of gravitational waves consisting of a constellation of three spacecraft, with launch planned for 2034.

Quote
LISA Pathfinder operations were split between the two experiments. Both thruster technologies have now been validated and will benefit future space projects such as large space observatories, or missions involving multiple spacecraft flying in formation.

The mission will continue taking data until 30 June, with a final experiment that will be pushing the precision limits of the test mass grabbing and releasing mechanisms – something of great importance for LISA. Then, after a series of final operational tests, the last command will be sent on 18 July.

A preliminary de-orbiting manoeuvre was already performed in April, nudging the spacecraft away from its orbit around the first Sun-Earth Lagrange point, L1, and towards a long-term stable parking orbit around the Sun.
Title: Re: ESA - LISA Pathfinder updates
Post by: bolun on 07/04/2017 07:55 am
LISA Pathfinder still hard at work

http://blogs.esa.int/rocketscience/2017/06/30/lisa-pathfinder-still-hard-at-work/

LISA Pathfinder sails toward the sun

http://blogs.esa.int/rocketscience/2017/07/03/lisa-pathfinder-sails-toward-the-sun/

Quote
On 18 July, the LPF mission will conclude with the final commands sent to switch off the on-board transmitter. Since April, the mission operations team in Darmstadt have been working to ensure a safe and smooth end-of-life for this fantastic technology demonstration spacecraft.

Quote
For disposal, the spacecraft has already performed a de-orbit manoeuvre to leave its Lagrangian orbit and start to drift ahead of the Earth in a heliocentric orbit around the Sun. The spacecraft now has an orbital period a few days shorter than that of the Earth, keeping the spacecraft safely out of the way and drifting serenely around the Sun.

Quote
30 June marked the end of the science mission ...
Title: Re: ESA - LISA Pathfinder updates
Post by: FutureSpaceTourist on 07/14/2017 07:50 am
Quote
LISA PATHFINDER: BAKE, RATTLE AND ROLL
13 July 2017

The final days of the LISA Pathfinder mission are some of the busiest, as controllers make final tests and get ready to switch off the gravitational pioneer next Tuesday.

Following 16 months of scientific effort, LISA Pathfinder completed its main mission on 30 June, having demonstrated the technology needed to operate ESA’s future LISA space observatory to study gravitational waves – ripples in spacetime predicted by Albert Einstein in his General Theory of Relativity.

The LISA mission will comprise three spacecraft orbiting some 2.5 million km apart in a triangular formation, with their ‘test masses’ isolated from all external forces bar gravity and linked by laser beams.

With the required sensitivity fully proven by LISA Pathfinder, teams are now using the spacecraft’s last days to conduct a series of technical tests on components and devices, making full use of every remaining minute.

“These tests will give us a better grasp of the craft’s behaviour and provide valuable feedback to the manufacturers about the characteristics of their equipment, in both routine and unusual conditions,” says spacecraft operations manager Ian Harrison.

“The gravitational wave detectors work by measuring the changing separation of two cubes that are in free-fall. Changes in the spacecraft’s state or any movement may interfere with the measurements, and we want to better understand these for the future mission.”

In addition to satellite movement, the delicate cubes on LISA Pathfinder can be influenced by variations in their environment, such as in temperature and magnetic interference.

Baking, rattling and rolling

Working at ESA’s mission control centre in Darmstadt, Germany, the controllers have been conducting daily tests since the mission formally ended its normal phase on 30 June. These could not be performed before because meeting the science goals required a very stable and ‘quiet’ environment.

Engineers have commanded the craft to turn to assess thermal effects on its systems, particularly the micropropulsion system, from solar illumination.

Repeating thermal tests previously performed on the ground will help to improve procedures for the future LISA mission.

Other tests are analysing the effect of magnetic interference, from the operation of pressure regulation valves in the cold-gas thruster system, on the spacecraft’s magnetic momentum, external forces and test mass control.

The teams have also been pushing the micropropulsion system and test-mass electrostatic sensing and control systems to their limits.

Spacecraft performance data have been recorded since the time of launch in December 2015 up to these last experiments, to determine the rate of hardware degradation in the harsh environment of space.

Boosting European industry

Results from this test series will be available to European hardware manufacturers for incorporation into future designs.

“These tests will help to eliminate variables that might influence the science results from future ESA missions, such as Euclid and LISA, and help reduce risk in their development,” says flight director Andreas Rudolph.

“The tests could go wrong for many reasons and might cause loss of data, or adversely affect the spacecraft, so they were not considered during the main technology demonstration phase of the mission.

“This is a great opportunity to test hardware in flight, with no effect on the mission objectives or final activities.”

Ready for lights out

Ground teams are getting ready to ‘passivate’ LISA Pathfinder, eliminating radio transmissions from the spacecraft and switching off most of the units.

In April, the spacecraft used its thrusters over five days to nudge itself into a safe orbit around the Sun, minimising any probability that it will return to the vicinity of Earth or Moon in the next 100 years, in line with ESA's requirement for space debris mitigation.

The final command switching off the craft is planned for around 18:00 GMT on 18 July.

“Before LISA Pathfinder, gravitational wave astronomy from space was a theoretical possibility, with its future implementation hidden behind a thick, dark wall,” says ESA’s Paolo Ferri, head of mission operations.

“This mission has opened a ‘door’ in this wall. The road to achieving a future mission that will detect gravitational waves is still very long, but we can see it and we can now start planning our long journey to reach it.”

http://m.esa.int/Our_Activities/Operations/LISA_Pathfinder_bake_rattle_and_roll (http://m.esa.int/Our_Activities/Operations/LISA_Pathfinder_bake_rattle_and_roll)

http://m.esa.int/spaceinvideos/Videos/2015/11/Inside_LISA_Pathfinder_with_narration (http://m.esa.int/spaceinvideos/Videos/2015/11/Inside_LISA_Pathfinder_with_narration)
Title: Re: ESA - LISA Pathfinder updates
Post by: FutureSpaceTourist on 07/14/2017 08:42 am
Quote
Today, teams will dump & wipe accumulated hardware test data frm onboard memory - make room for end-of-mission commands #eom #LISAPathfinder

https://twitter.com/esaoperations/status/885766590381404160 (https://twitter.com/esaoperations/status/885766590381404160)

Quote
Later, #LISAPathfinder will be commanded to spin up - to further understand its behaviour when manoeuvring #LISAPathfinder

https://twitter.com/esaoperations/status/885766690730061824 (https://twitter.com/esaoperations/status/885766690730061824)
Title: Re: ESA - LISA Pathfinder updates
Post by: eeergo on 07/14/2017 02:28 pm
Quote from: ESAOperations
Update from LISAPathfinder Operations Manager Ian Harrison at ESOC: Today's in-orbit spin-up test postponed. There has been an increase in solar activity, so there's a last-min request to resume LISAPathfinder 'science mode' & measure charge build-up on the test masses. The team are also repeating the low-pressure test on the Cold Gas Thruster system down to 0.2bar. Busy final days! LISAPathfinder proving to be a valuable mission right to the end! Last command 20:00CEST 18.07


https://twitter.com/esaoperations/status/885847575487762433 (https://twitter.com/esaoperations/status/885847575487762433)


Related to this, from SpaceWeather.com:


Quote from: http://www.spaceweather.com/archive.php?view=1&day=14&month=07&year=2017
After days of suspenseful quiet, huge sunspot AR2665 finally erupted on July 14th (0209 UT), producing a powerful and long-lasting M2-class solar flare. Extreme ultraviolet telescopes onboard NASA's Solar Dynamics Observatory recorded the blast. Remarkably, the explosion persisted for more than two hours, producing a sustained fusillade of X-rays and energetic protons that ionized the upper layers of Earth's atmosphere. Shortwave radio blackouts were subsequently observed over the Pacific Ocean and especially around the Arctic Circle. Of even greater interest is the coronal mass ejection (CME). The explosion hurled a bright CME away from the blast site, and it appears to be heading for Earth. This expanding cloud will likely reach our planet on July 16th, possibly sparking geomagnetic storms and high-latitude auroras when it arrives.
Title: Re: ESA - LISA Pathfinder updates
Post by: FutureSpaceTourist on 07/18/2017 11:03 am
Quote
ESA Operations‏ Verified account @esaoperations 2m2 minutes ago

#LISAPathfinder last command transmitted today ~20:00CEST - follow via Facebook live starting 19:45CEST https://www.facebook.com/EuropeanSpaceAgency/

https://twitter.com/esaoperations/status/887265703509848068 (https://twitter.com/esaoperations/status/887265703509848068)

19:45 CEST is 17:45 UTC
Title: Re: ESA - LISA Pathfinder updates
Post by: FutureSpaceTourist on 07/18/2017 12:24 pm
https://www.youtube.com/watch?v=bPNXZnaLbe4 (https://www.youtube.com/watch?v=bPNXZnaLbe4)

Quote
Published on 18 Jul 2017

The LISA Pathfinder mission ends on 18 July 2017 after a successful demonstration of the technology needed to detect gravitational waves in space. These vibrations in spacetime, first predicted by Einstein over a hundred years ago, are produced by huge astronomical events - such as two black holes colliding - and will allow scientists to open new windows into our universe.

The success of the LISA Pathfinder mission has paved the way for the newly selected LISA mission which, when built and launched, will detect gravitational waves from objects up to a million times larger than our Sun.

The film features interview soundbites from Dr Paul McNamara, LISA Pathfinder Project Scientist, at the European Space Agency’s European Technology and Science facility (ESTEC) in The Netherlands.
Title: Re: ESA - LISA Pathfinder updates
Post by: FutureSpaceTourist on 07/18/2017 02:47 pm
Quote
ESA Operations‏ Verified account @esaoperations 9m9 minutes ago

We have #AOS! #LISAPathfinder controllers established contact with their craft for the last time just after 16:00CEST

https://twitter.com/esaoperations/status/887320633343868929 (https://twitter.com/esaoperations/status/887320633343868929)
Title: Re: ESA - LISA Pathfinder updates
Post by: eeergo on 07/18/2017 03:10 pm
https://twitter.com/esaoperations/status/887325525739536384

Quote from: esaoperations
Update from the Main Control Room: A-chain of #LISAPathfinder's redundant on-board systems now OFF & craft is flying on its B-chain.
Title: Re: ESA - LISA Pathfinder updates
Post by: Chris Bergin on 07/18/2017 05:59 pm
And that's the end....
Title: Re: ESA - LISA Pathfinder updates
Post by: Chris Bergin on 07/18/2017 05:59 pm
Article:
https://www.nasaspaceflight.com/2017/07/farewell-lisa-pathfinder-sleep/
Title: Re: ESA - LISA Pathfinder updates
Post by: catdlr on 08/18/2017 03:44 am
LISA Pathfinder switch off: Mission summary and beyond

European Space Agency, ESA
Published on Aug 17, 2017


Following 16 months of scientific effort, LISA Pathfinder completed its main mission on 30 June 2017, having demonstrated the technology needed to operate ESA’s future LISA space observatory to study gravitational waves – ripples in space-time predicted by Albert Einstein.

On 18 July, the spacecraft was shut down after being placed in a safe disposal orbit. The final command was sent from ESOC, ESA's European Space Operations Centre, at 19:57 CEST that evening.

That day, scientists, mission controllers, and the mission's management team gathered at ESOC, Darmstadt, Germany, for a presentation on the successes of the mission prior to the shut-down. This video was recorded between 16:00-18:00 CEST, and includes highlight presentations on the mission's achievements.

Speakers:
- Rolf Densing, ESA Director of Operations
- Andreas Rudolph, ESA Head of Astronomy Missions Division
- Ian Harrison, ESA Spacecraft Operations Manager
- Paul McNamara, ESA LISA Pathfinder Project Scientist,
- Prof. Stefano Vitale, Principle Investigator for the LISA Pathfinder Mission, University of Trento
- Phil Barela, NASA/JPL project manager for LISA Pathfinder Disturbance Reduction System
- Colleen Marrese-Reading, JPL/Caltech
- Prof. Karsten Danzmann, Director at the Max-Planck Institute for Gravitational Physics, LISA Pathfinder Co-Principle Investigator

More about LISA Pathfinder:
http://sci.esa.int/lisa-pathfinder/

https://youtu.be/A8qbgJJUXac?t=001

https://youtu.be/A8qbgJJUXac
Title: Re: ESA - LISA Pathfinder updates
Post by: bolun on 01/25/2018 10:14 am
LISA Pathfinder wins American Astronautical Society award

http://www.esa.int/Our_Activities/Space_Science/LISA_Pathfinder_wins_American_Astronautical_Society_award

Winners of 2017 American Astronautical Society Awards Announced

http://astronautical.org/2018/01/22/winners-of-2017-american-astronautical-society-awards-announced/
Title: Re: ESA - LISA Pathfinder updates
Post by: bolun on 02/06/2018 06:06 pm
LISA Pathfinder performance analysis

Analysis of the LISA Pathfinder mission results towards the end of the mission (red line) compared with the first results published shortly after the spacecraft began science operations (blue line). The initial requirements (top, wedge-shaped area) and that of the future gravitational wave detection mission LISA (middle, striped area) are included for comparison, and show that it far exceeded expectations.

At the heart of the LISA Pathfinder spacecraft, two identical, 2 kg, 46 mm gold–platinum cubes were falling freely through space under the influence of gravity alone. The LISA Pathfinder team measured the remaining forces acting on the test masses, and identified the main sources of noise, depending on the frequency.

Compared with the initial results following the first two months of science operations, statistical analysis over the larger dataset allowed scientists to measure the noise at even lower frequencies than expected, down to 20 µHz.

In addition, the many more months in space allowed a 10-fold reduction in the effect of escaping residual gas pressure inside the spacecraft, which caused gas molecules to bounce off the cubes. More data also led to improved understanding of the small inertial force acting on the cubes caused by a combination of the shape of LISA Pathfinder’s orbit and the effect of the noise in the signal of the startrackers used to orient it. A more accurate calculation of the electrostatic forces of the onboard electrical systems and magnetic fields has also now eliminated a systematic source of low-frequency noise.

Overall, the results show that LISA Pathfinder has clearly surpassed its original requirements, reaching a level of precision closer to that required by the future gravitational-wave observatory, LISA.

- Related article: ESA creates quietest  place in space (http://www.esa.int/Our_Activities/Space_Science/ESA_creates_quietest_place_in_space)

http://www.esa.int/spaceinimages/Images/2018/02/LISA_Pathfinder_performance_analysis

Image credit: ESA/LISA Pathfinder Collaboration
Title: Re: ESA - LISA Pathfinder updates
Post by: bolun on 03/09/2020 01:25 pm
LISA PATHFINDER LEAD SCIENTIST AWARDED PRESTIGIOUS PRIZE

6 March 2020

Professor Stefano Vitale, principal investigator of ESA's LISA Pathfinder and currently the chair of ESA's Science Programme Committee, has been honoured with the 2020 Tycho Brahe Medal for leading the ambitious mission that demonstrated technology to detect gravitational waves from space.

The annual prize has been awarded by the European Astronomical Society since 2008 to acknowledge the "development or exploitation of European instruments or major discoveries based largely on such instruments".

A Professor of Physics at the University of Trento, Italy, Stefano Vitale joins a prestigious list of winners that have been pushing the boundaries of contemporary research in space science and astronomy across Europe.

https://sci.esa.int/web/lisa-pathfinder/-/lisa-pathfinder-lead-scientist-awarded-prestigious-prize