Author Topic: Russian RadioAstron (Spectr-R) update  (Read 37921 times)

Offline websquid

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Re: Russian RadioAstron (Spectr-R) update
« Reply #40 on: 06/30/2013 01:02 PM »
Here it is. Sorry for the long post but you asked for it ;D

RadioAstron - The Interview

Raumfahrer.Net: At first I would like you to tell us a bit about your work. In which field do you work and how did you come to RadioAstron?

Kirill Sokolovsky: In fact I have to jobs. My main job is the work at the ASC LPI - here I work for the RadioAstron project. I am also a part-time software developer at the Sternberg-Astronomy-Insitute of the Moscow State University. Here I work on variable stars. This work has no connection to RadioAstron.

I was a student at the Moscow University and then I started working at ASC to get my diploma (the work was about VLBI - Very Long Baseline Interferometry). At that time they searched people for VLBI, there was the perspective that one day RadioAstron would fly.

RN: At which time did the ASC search people?

KS: That is some time ago. I began 2006 to work there.

RN: That is seven years ago. Did you work on RadioAstron at that time?

KS: I did not work on this project then. I worked with data of earth-based  VLBI observations. When I got my diploma, I went to Bonn(Germany) and started working at the Max-Planck-Institute for Radio Astronomy. (MPIfR) to get my Ph.D. I continued to work on earth-based VLBI. Really incorporated in RadioAstron were I since summer 2011, when I came back to Moscow. Before the satellite started, RadioAstron was mainly work for engineers. As an astronomer, I could not really help until that time. After the launch things got much more interesting for me!

RN: After the launch it lasted some months, until scientific observations started. How did you and the other astronomers at ASC feel, when you got the first useful data?

KS: I would say, we were surprised. And very excited, of course! The turning point, when we realized, that this experiment was a success, was some time after the observation on November 14 in 2011 - the first VLBI test. The 100m-radio telescope in Effelsberg, the three russian 32m-telescopes Svetloe, Zelenchukskaya and Badary and the ukrainian 70m-telescop in Evpatoria did participate in this test.

At first, we did not have working software to do the data reduction. We realized later, that the ASC-Correlator software contained a bug, which can only be discovered when working with moving antennas (like the Spectr-R Satellite in its orbit). In principle we created two simplify correlator softwares from scratch, to detect the interference fringes and to find the bug in the "big" correlator.

Later James Anderson at MPIfR developed for the DiFX software correlator the ability, to work with RadioAstron data as well. DiFX is the de-facto standard for earth-based VLBI data processing. But when we made the first tests, this software was not available.

Also there is to say, that there was a smooth transition from technical tests to scientific observations. The system was in a constant debugging process until summer 2012. Only then we were convinced, that the whole systems works correct and that we can now collect good scientific data.

RN: You mentioned the participation of the MPIfR. What do you think about this and how important is this cooperation?

KS: The cooperation with MPIfR was crucial for the project. At first, they granted us observation time in Effelsberg for RadioAstron tests. The Effelsberg telescope proved itself as one of the most useful telescopes during the tests and later the Early Science Program (ESP, running from february 2012 until june 2013). It is very sensitive, fully steerable and is often used for VLBI. That is why the people there watch every detail necessary for interferometric observations and calibration. And it is located on the same continent as the tracking station in Pushchino near Moscow. Therefore there are long common timeframes for observations with the satellite and the ground telescope.

In addition the MPIfR (especially its director Anton Zensus) supported data analysis and data logistics. The main point was the implementation of RadioAstron-support in DiFX. This was a big deal. It became the most important software for data analysis, at least in our AGN-group (active galactic nuclei) group.

RN: Is DiFX only used in Bonn or also at the ASC?

KS: Most of the "DiFXing" for the RadioAstron AGN survey is done in Moscow. Bonn correlates the imaging experiments, which were performed together with the European VLBI Network (EVN). These produce large amounts of data (around 20  TB per observation) and the MPIfR correlator can handle this easily, which is not really true for us in Moscow.

We do not have DiFX on our supercomputer at ASC (it uses the ASC-made software) and the machines which run DiFX do not have enough power to correlate a complete imaging experiment.

At the moment there is work on a detailed comparison between the results of both correlators. But to make this reasonable, all datasets have to be processed with both softwares.

So far there were three imaging experiments together with the EVN. The first was in March 2012 and is completely processed. The processing of the other two is still under way (the observations were in october 2012 and march 2013).

RN: The first image was published. Do you plan to publish the produced images?

KS: For sure yes!

But at the moment we do not have correlated datasets for the other two experiments and when we have these, it can still last one or two months until the final images are created. That is how things go with VLBI. The data processing is much more complicated and "delicate" as in other fields of astronomy, which I did work on.

But I should add that most of the observations are not done in imaging mode. The aim of such observations is just the detection of interferometric fringes. The amplitude of the fringes can be measured for a range of baselines and this can be compared with a simple model of the source. For example we can assume a gaussian model of the source and measure its size.

This was the way earth-based VLBI was done in the time when there were only few telescopes which could do such observations. The problem with image reduction is that you need to cover the so called uv-plane as good as possible. You need many telescopes with different baselines.

When RadioAstron is far from earth we have the situation that all ground telescopes are in fact at the same place - so no imaging is possible. Instead we almost have an interferometer with only two elements. This means we only can create images, when the satellite is not more than 3-5 earth diameters away. At this baseline we do not have the highest resolution, but we can do imaging. At longer baselines we can only compare the measured visible amplitude with a simple model (for example a gaussian). In this case we only can determine the size and brightness of the source. In addition we can determine roughly the shape (is the object stretched or not?). The more data points we get, the more complex models can be used to describe the object.

RN: You mentioned size and brightness, which can be measured with RadioAstron. Often there is talked about "brightness temperature". What does this mean and how can you measure it?

KS: Brightness temperature is a certain way of radio astronomy to talk about surface brightness, something that is determined in optical astronomy as magnitude per area. In the easiest case brightness temperature is the brightness of the object divided by its size. In addition there is a factor to convert this value in Kelvin.

There is some freedom in the way you determine the "size"  of a source when the real size can not be determined. Instead you have a measured interferometric visibility which you can compare with a model. So a spherical model had a slightly different size than a gaussian model for the same source. But in general the difference is for all possible models only a small factor. 10^14K can always be distinguished from 10^11K without problems, no matter which model is used.

RN: What do this different models mean?

KS: The gaussian model is simply a radio source, which brightness profile follows a gaussian curve. There are two variants of this model: circular and elliptical. The gaussian model was simply chosen because it is simple to calculate with it: The Fourier transform of a gaussian curve is another gaussian curve. And the visibility measured by the interferometer is the Fourier transform of the brightness distribution of the source.

A spherical radio source has a slightly different brightness profile, it follows the surface of a sphere. In both cases this is no physical model of the source, but only a "toy model" which allows us to characterize size and flux density of a source. A source where we see almost no details, but where we already can see, that it is no point source - but a slightly increased point source (a typical situation for interferometry).

RN: How does the ability to measure brightness temperature depend on the baseline?

KS: You need many observations with different baselines. When you consider the low sensitivity of the space radio telescope, a simple model (a point with a certain size) seems to fit for all the baselines, even for the extreme angular resolution RadioAstron can achieve.

From a physical point of view, this bright spot (when observing AGN) is the brightest part of the relativistic jet, where the jet becomes transparent for its own synchrotron radiation. This area is called the VLBI-core, the brightest spot in a many lightyears long jet. But there are concurring ideas, what a VLBI-core really is. In principle there could be other options, not only these transparency-thing.

RN: What are these alternate models?

KS: A reasonable alternative is that a VLBI-core is a collimation shock in the jet. In this model the core would be a certain physical region, not a place were the jet becomes transparent for the observed frequency. There are some more models, but these do not seem to work for radio-loud AGN.

A way to test the "synchrotron transparency" is to determine the size of a VLBI core at different wavelengths. The transparency model predicts that the VLBI core should be bigger for smaller frequencies. The reason is that the jet has an opening angle, you could speak of the jet as a cone. For smaller frequencies the jet becomes transparent in a larger distance to its base.

There were ground based observations on this question, but with RadioAstron we can measure this effect with much higher accuracy. The collimation shock theory in contrast does not predict any difference in size and position at different wavelengths.

RN: Are there already hints which model fits better?

KS: At the moment - no. We are still under way to collect more data.

RN: Do you believe that you can unveil the real nature of VLBI cores?

KS: Yes. We only have one real size measurement - the core of the blazer 0716+714 from the imaging experiment with the EVN. We need more time to determine this for other sources based on the fringe survey. For some sources (for example for BL Lac) we should have enough data, but we need more time to process it. I am very sure that we will solve this question with RadioAstron finally.

RN: Another thing is the interstellar matter (ISM). It was expected that this would scatter radio waves but it seems like this does not happen in the expected way?

KS: Yes! The interstellar scattering is a big thing for RadioAstron. I am not an expiret for this, but as I hear from my colleagues the difference between expected and observed scattering is very huge. The scattering is there but very smaller than expected. It seems in general that the scattering is not as homogenous as expected. This is a reason why it is in total smaller than thought before.

In fact was the expectation of strong scattering a large point of objection before RadioAstron started. There were many very smart people who thought that RadioAstron could not see anything beyond 1-2 earth diameters baseline. With the current orbit we reach up to 25 earth diameters. This means the resolution is convenient for everything one can dream of. The question is - what are the smallest details which we can see despite the interstellar scattering? We already can say that we see much more than some experts expected.

RN: When did you realize this behavior of the ISM?

KS: We are the first who measured this directly with an interferometer with baselines larger than earth! For AGN there were early hints, based on the intra-day variability of sources (fast changes of the flux density caused by scattering) that there size is small. But these estimates are even more model-dependent than the size measurement with VLBI.

RN:  So the scattering itself changes in hours?

KS: Yes! And this is something which we want to study in the next years in detail. A large point of the AGN survey program for the next year is the combination of RadioAstron observations with earth-based measurements of daily flux variation to study the scattering.

RN: This sounds a bit like this behavior is comparable with our atmosphere in visible light - like stars blink. Is this comparison legit?

KS: Yes, this analogy seems to be fully correct. And this immediately leads to the idea, wether it is possible to create something like an optical speckle interferometer  for radio waves?! I can not answer this question. Maybe it is possible, but I do not know enough about this topic to say it for sure.

RN: So we have to wait for more information. You mentioned the following years. At the moment the Early Science Program is running, which will end soon. In july the Key Science Program starts. The ESP had a  strong focus on AGN. Will this be the same in KSP or will other topics get a bigger fraction of observation time?

KS: Emanating from the accepted KSP proposals the most observation time will still be used for AGN. Maser and pulsars will also be observed, but I think their fraction will roughly stay the same. I have an accepted project to study transient radio sources like supernovae or tidal disruption events, but this is an experimental project which was never tried before with space-VLBI. So it is not clear whether something will come out of it. But I think it is worth a try.

RN: Which countries made the most KSP proposals? Russia is for sure leading, but in which other countries is the largest interest in RadioAstron?

KS: Add first I would like to add something to the AGN observations: There will be more imaging experiments for sure. Not just three in one year.  Concerning the origin of the proposals I think that most of them, if not all, come from international groups consisting of scientists from many different countries as co-authors. I know Germany, the USA, Spain, Australia, Poland and Japan and for sure I am forgetting some. Sadly there is not yet official information about the accepted proposals. The RadioAstron Program Evaluation Committee made its decision but some of the proposals depend also on the evaluation from the project committees of single ground telescopes or networks like EVN or VLBA, so there is no final list of KSP projects. It can happen that some of the projects accepted for RadioAstron are rejected by ground telescopes so they can not be  carried out.

RN: Can you estimate how many imaging experiments will be performed in the first KSP period (july 2013 - june 2014)?

KS: The imaging experiments depend the most of the availability of ground telescopes. A chance for these experiments is at each perigee passage of Spektr-R, roughly every 8,5 days. This is under the assumption that the tracking station in Green Bank is then available. It is hard to say how many observations really will be performed. I expect at least ten imaging experiments, maybe more. The KSP observation program is not yet fixed. I think there will be no imaging experiments until september because of severe visibility restrictions in the summer. So for the first two months of the KSP there will only be simple fringe detections for AGN, pulsars and masers, like the most time during the ESP.

RN: When will the tracking stations in Green Bank and South Africa start their work?

KS: The tracking station in Green Bank will start soon. Under consideration of possible delays our current best estimate is that it will be available in september. All papers between USA and Russia are signed, the electronic equipment is currently tested in Pushchino. A potential delay risk is the russian toll, but the work is under way. The control system of the 43m-telescope in Green Bank was tested, so I think it is ready. After the data recording equipment is delivered there will be of course some time needed to install and test it. So the most optimistic guess is july, the more realistic is september.

The south african station seems to be still on the level of official talks and agreements. There is currently no technical work done for it. So I think the south african station needs at least a year, maybe longer, until it works.

Offline websquid

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Re: Russian RadioAstron (Spectr-R) update
« Reply #41 on: 06/30/2013 01:41 PM »
In addition, here the images used in the original article:

Kirill Sokolovsky in the control room of the Effelsberg radio telescope


Artistic depiction of Spektr-R. NOTE: This is not correct, it shows an old design based on the AM-Bus instead of the Navigator-Bus


The first image created using RadioAstron


The 43m-telescope in Green Bank - the new tracking station

Offline baldusi

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Re: Russian RadioAstron (Spectr-R) update
« Reply #42 on: 06/30/2013 03:50 PM »
Congratulations! You have more than a couple of articles of information there. A Reuters article could do wonders to this mission awareness.

Offline websquid

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Re: Russian RadioAstron (Spectr-R) update
« Reply #43 on: 06/30/2013 05:32 PM »
A Reuters article could do wonders to this mission awareness.
Yes, you are right.... I hope that this mission will get some broader coverage when results are released. A paper published in Nature or Science would for sure give a little boost. At the moment there are some papers under preparation about the results of the ESP, so maybe then the Reuters article (or whoever similar) may come...

Talking about the Green Bank Tracking Station, here some news:
The equipment was shipped some days ago to Green Bank. If all goes well it can be installed until july 14. Late july and august are planned for tests, the station is expected to be fully operational in september. Then the  observation time for RadioAstron will roughly double.

Offline websquid

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Re: Russian RadioAstron (Spectr-R) update
« Reply #44 on: 08/07/2013 05:58 PM »
Some short updates...

-The radio telescope "TNA-1500" in Kalyazin (Oblast Tver, Russia), a 64m-dish is now refurbished and able to work as a ground telescope for observations. Tests in single-dish mode were very successful, I expect first interferometric observations in september (initially planned observation in august was cancelled).

-The SFXC-Correlator at JIVE (Joint Institute for VLBI in Europe) was upgraded to be able to work with RadioAstron data. Following the ASC-Correlator at LPI in Moscow and the DiFX-Software developed at MPIfR in Bonn it is the third working correlator. This will further reduce the time needed for data processing.

The first data set used for the tests was the imaging experiment from last october. Technically this was highly interesting - C/K-Band imaging of the quasars 2013+370 and 2037+511, spacecraft position tracking was done with EVN-PRIDE. This means, that 4 telescopes of the EVN did observe the Spektr-R spacecraft and determined it's position using VLBI. This allows an extremely exact measure of the position (error <10cm, while classic orbit reconstruction has errors up to 500m). Better position measurements improves the  quality of the final image.

-The Green Bank Tracking Station (called GBES in official project documents) was successfully tested on august 1. This was the second test - the first test failed, signal decoding was not possible. Looks like there were some twisted cables ;) So as planned, it will be operating in september and largely increase the usable observation time (roughly double).

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #45 on: 08/16/2013 06:07 AM »
http://www.nrao.edu/pr/2013/RadioAstron/

Thursday, August 15, 2013

Contact:

Charles Blue, Public Information Officer
Charlottesville, Virginia
(434) 296-0314
cblue@nrao.edu

Venerable NRAO Telescope Reborn as Earth-based Antenna for Orbiting RadioAstron Satellite
 
The trailblazing 43 Meter (140 Foot) Telescope at the National Radio Astronomy Observatory (NRAO) in Green Bank, W.Va., has been given new life as one of only two Earth stations for the Russian-made RadioAstron satellite, the cornerstone of astronomy's highest-resolution telescope.

RadioAstron is the farthest element of an Earth-to-space spanning radio telescope system. Launched in July 2011, RadioAstron -- when linked to large, ground-based radio telescopes like NRAO's massive Robert C. Byrd Green Bank Telescope (GBT) -- creates a virtual radio telescope that extends up to 220,000 miles (350,000 kilometers) across, which is about the same distance as the Earth to the Moon.

From late July 2013 through early August, engineers and astronomers from the United States and Russia successfully installed sophisticated receiving and signal processing instruments on NRAO's 43 Meter Telescope, which was completed in 1965 and retired from routine astronomical observations in 2001. The telescope has now been transformed into one of only two antennas (the other near Moscow) that can receive and process the scientific data from RadioAstron. The addition of the antenna at Green Bank effectively doubles the spacecraft's scientific capabilities.

"NRAO has built the most capable radio telescopes in the world. After nearly half a century of service, the 43 Meter Telescope is once again proving its innovative design and precision construction have much to offer the astronomical community," said Karen O'Neil, the NRAO site director at Green Bank and project lead for the Green Bank portion of RadioAstron.

"The international scientific community is excited about RadioAstron because of the unique science that it will enable," said Ken Kellermann, a scientist at the NRAO in Charlottesville, Va. "By combining its data with leading ground-based telescopes, we will have an incredibly powerful research tool, which will provide extraordinary angular resolution enabling the study of quasars, cosmic masers, and the interstellar medium in unprecedented detail."

RadioAstron uses the same principles as other radio telescope arrays -- like the Karl G. Jansky Very Large Array (VLA), the Atacama Large Millimeter/submillimeter Array (ALMA), and the Very Long Baseline Array (VLBA) -- in which data from each antenna is combined to effectively form a single telescope. The farther apart the antennas, the higher the resolution the telescope is able to achieve.

As part of its early science program, RadioAstron joined the GBT, VLA, and VLBA to achieve a resolution better than one ten-thousandth of an arcsecond, which is several hundred times better than the Hubble Space Telescope and the highest resolution ever achieved in astronomy. The satellite was more than 70,000 miles (112,654 kilometers) away during that observation.

The sensitive radio receivers aboard the spacecraft were fabricated in Russia, India, and Australia. They include two very low noise amplifiers developed at the NRAO's Central Development Laboratory in Charlottesville, Va.

"The RadioAstron early science program, which has just finished, has already brought many surprises to scientists studying quasars, pulsars, and interstellar medium. We expect even more exciting outcomes from our just-beginning key science program," said Yuri Kovalev, the RadioAstron project scientist from the Lebedev Physical Institute of the Russian Academy of Sciences.

Funds to develop and operate the 43 meter antenna as part of the RadioAstron mission are provided by the Russian Federal Space Agency.

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

###

Image Caption 1: NRAO's 43 Meter Telescope has been transformed into the Green Bank antenna of the RadioAstron project.
Credit: NRAO/AUI/NSF.

Image Caption 2: Artist rendering of the orbiting RadioAstron satellite, the farthest element in an array of radio antennas that combine to form the highest resolution instrument in all of astronomy.
Credit: Lavochkin Assocition.

Image Caption 3: New equipment (a feed horn), being installed on the 43 meter antenna at Green Bank during its recent upgrade for RadioAstron.
Credit: Galen Watts; NRAO/AUI/NSF.


Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #46 on: 08/16/2013 06:10 AM »
Astro Space Center
RadioAstron Newsletter
Number 21
August 15, 2013
======================

Green Bank Earth station (GBES)

A group of engineers from Astro Space Center has visited the National Radio Astronomy Observatory, Green Bank, to work together with local NRAO staff on the installation of the tracking station equipment. The instrumentation which has been installed on the 140-ft telescope was manufactured in Russia and is similar to that which has been in operation now for two years at Puschino.  We are happy to report that the equipment was delivered to Green Bank and installed and tested without problems and is now operational. The tests of the GBES went very well.  On 1 August 2013, science data from the RadioAstron space radio telescope was successfully recorded and sent to Moscow for evaluation. Due to the high gain of the 140-ft antenna, the detected signal power level was found to be well above operational requirements, and the bit error rate satisfactorily low.  The results of Doppler measurements of the satellite velocity agreed well with measurements made sequentially by the Green Bank and Pushchino stations.

Active observations of the RadioAstron AO1 Key Science Program will start in late August 2013 with a reduced duty cycle in order to fully develop a detailed operating model.  Starting in early October, we expect RadioAstron scientific observations to be fully supported by the GBES.

We congratulate everyone involved in this achievement, thank the RAO-GB staff for their traditionally very high level of support and wish all of us happy observing with two available RadioAstron tracking stations during the execution of AO1.

The NRAO press release can be found here:
http://www.nrao.edu/pr/2013/RadioAstron/

Nikolai Kardashev (nkardash@asc.rssi.ru)
Yuri Kovalev (yyk@asc.rssi.ru)
« Last Edit: 09/13/2014 04:14 PM by Salo »

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #47 on: 08/16/2013 09:20 AM »

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #48 on: 11/18/2013 04:21 PM »
Astro Space Center
RadioAstron Newsletter
Number 22
November 18, 2013
======================
100 revolutions around Earth!

We would like to thank Russian and international RadioAstron partners, scientists and engineers for their hard work on the occasion of Spektr-R completing 100 revolutions around the Earth since the launch of the space telescope! The spacecraft continues the key science program which started in mid-2013. Most of the teams have already performed the rst experiments within their accepted proposals. In particular, for the rst time space VLBI fringes were detected at 92 cm from an active galactic nucleus (AGN). See the Figure for details. This opens new opportunities in both studying synchrotron self-absorption in jet regions in AGNs and using AGNs at long radio wave lengths for reconstructing parameters of interstellar medium in our galaxy.
The Green Bank Earth station started active operations in September 2013. As a result, the overall accessible RadioAstron observing time has increased substantially, and the accuracy of the RadioAstron orbit reconstruction has improved very signi cantly. Both tracking stations, in Pushchino and Green Bank, continue to operate very reliably.

AO-2 plans

The Announcement of Opportunity 2 for RadioAstron observations in the period July 2014 {June 2015 is expected to be released in early December 2013. The AO-2 proposal deadline will be 27 January 2014. Proposals will be invited for both key science programs and general observing time.

One more software correlator becomes RadioAstron-friendly

The EVN Data processor at JIVE, also known as the JIVE SFXC correlator, has successfully received fringes in a number of RadioAstron data sets at 1.6, 5 and 22 GHz, including spectral line fringes at the latter frequency. For additional details see EVN Newsletter 36 http://www3.mpifr-bonn.mpg.de/div/vlbi/newsletter/36/
It is expected that a part of the upcoming RadioAstron-EVN observations within the AO-1 and AO-2 cycles will be correlated at JIVE.

The COSPAR 40th science assembly

The COSPAR 40th science assembly will be held in Moscow in early August 2014. One of the science events, E1.10, will be devoted to present and discuss RadioAstron results. Details of the meeting will be available soon from the conference web site. Everyone is invited.
https://www.cospar-assembly.org/ & http://cospar2014moscow.com/

Nikolai Kardashev (nkardash@asc.rssi.ru)
Yuri Kovalev (yyk@asc.rssi.ru)
« Last Edit: 09/13/2014 04:15 PM by Salo »

Offline websquid

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Re: Russian RadioAstron (Spectr-R) update
« Reply #49 on: 12/24/2013 07:23 PM »
Planning the future of RadioAstron 8)
http://www.asc.rssi.ru/radioastron/ao-2/ao2.html
Quote
RadioAstron Announcement of Opportunity - 2

The space VLBI Mission RadioAstron, led by the Astro Space Center (ASC)
of Lebedev Physical Institute, provides a range of specific and unique
capabilities for detecting and imaging sources of cosmic radio emission
at the highest angular resolution. The optimal utilization of these
capabilities relies on the construction and execution of a balanced
scientific program for the Mission. The scientific program of
RadioAstron consists of three major parts: the Early Science Program
(ESP), Key Science Program (KSP), and General Observing Time (GOT)
projects. The Early Science Program, which finished in June 2013,
explored the main scientific capabilities of RadioAstron observations
and paved the way for the subsequent KSP and GOT programs.

RadioAstron KSP observations commenced in July 2013. The KSP is aimed
specifically at focusing on the areas of strongest scientific impact of
RadioAstron and ensuring a long-lasting scientific impact for the
Mission. KSP observations within the AO-1 period are being carried out
between July 2013 and June 2014, inclusive.
Looks like all goes well and they do their work. Hopefully it does not last to long until real scientific papers are released... (but recall, VLBI-papers are called "fast" when they are published 2 years after observation... so just be patient)
« Last Edit: 12/24/2013 07:27 PM by websquid »

Online Artyom.

Re: Russian RadioAstron (Spectr-R) update
« Reply #50 on: 02/12/2014 12:17 PM »
Spektr-R: officially amazing

We are happy to share with you the news that one of many records achieved within the RadioAstron Space VLBI project — the 10-m diameter space radio telescope Spektr-R — has entered the Guinness book.

See the attached copy of the Guinness certificate.

"Earth is the cradle of humanity, but one cannot live in a cradle forever." - Konstantin Eduardovich Tsiolkovsky.

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #51 on: 06/11/2014 07:28 PM »
http://www.asc.rssi.ru/radioastron/news/news_en.pdf

Astro Space Center
RadioAstron Newsletter
Number 24
6 June 2014
======================
The RadioAstron AO-2 open science program starts in July 2014 The rst year of the RadioAstron open science program AO-1 is coming to its end in June 2014.
Astro Space Center and its Russian and international partners have successfuly performed science experiments within all approved AO-1 projects (see the list of projects in the RadioAstron Newsletter No. 20). First results of the AO-1 program will be presented by science teams at the COSPAR-2014 General Assembly in Moscow on 7 and 8 August 2014, see the program of the event: https://www.cospar-assembly.org/admin/session_cospar.php?session=430
Starting from July 2014, the RadioAstron mission will move into the second year of its open program, AO-2 observations will continue until June 2015. The second RadioAstron Announcement of Opportunity has invited proposals of the following two types: the \Key Science Program" (KSP) and \General Observing Time" (GOT). See for details the full set of announcement documents in  http://www.asc.rssi.ru/radioastron/ao-2/ao2.html.
All proposal were evaluated by the RadioAstron Program Evaluation Committee (RPEC) whichwas appointed by the RadioAstron International Science Council (RISC). Results of the evaluation were approved by the RadioAstron project director. RPEC members for AO-2 were Dave Jauncey (CSIRO, Australia), Tim Pearson (Caltech, USA), Misha Popov (ASC Lebedev, Russia), Richard Porcas (chair, MPIfR, Germany), Elaine Sadler (U. Sydney, Australia), and Mark Reid (Harvard-Smithsonian CfA, USA). Below we list 16 accepted projects which have requested observations with RadioAstron during the AO-2 period in their submission order:
 KSP: \Substructure in Pulsar Scattering Disks", PI: Carl Gwinn (UCSB, USA);
 GOT: \Zooming into the high-redshift Universe", PI: Leonid Gurvits (JIVE, the Netherlands);
 GOT: \Space VLBI study of the inner region of the BL Lac source Markarian 501", PI: Gabriele Giovannini (IRA INAF, Italy);
 GOT: \Crab Pulsar Giant Pulse Study with RadioAstron", PI: Alexey Rudnitskiy (ASC Lebedev, Russia);
 GOT: \RadioAstron-VLBI observations: Study of Local Scattering Material", PI: Tatiana Smirnova (PRAO ASC Lebedev, Russia);
 GOT: \Substructure in the Scattering Disk of SgrA*", Michael Johnson (Harvard-Smithsonian Center for Astrophysics, USA);
 GOT: \Imaging of micro-structures of OH and H2O masers with ultimate angular resolution", PI: Hiroshi Imai (Kagoshima University, Japan);
 GOT: \RadioAstron Orbital Precession Imaging of Young AGN Jets", PI: Matthew Lister (Purdue University, USA);
 KSP: \Probing the innermost regions of AGN jets and their magnetic elds", PI: Andrei Lobanov (MPIfR, Germany);
 GOT: \Structure and physics of compact jets in AGN", PI: Manel Perucho (Valencia University, Spain);
  KSP: \Space VLBI Survey of AGN at the Highest Angular Resolutions", PI: Yuri Kovalev (ASC Lebedev, Russia);
 GOT: \Search for new water and hydroxyl maser sources with spots of ultra-small angular size", PI: Andrey Sobolev (Ural Federal University, Russia);
 KSP: \RadioAstron hydrogen maser gravitational redshift experiment", PI: Valentin Rudenko (Lomonosov Moscow State University, Russia);
 GOT: \Space-VLBI investigation of the core shift e ect in the blazar 3C 454.3", PI: Kirill Sokolovsky (ASC Lebedev, Russia);
 GOT: \H2O Masers and Protoplanetary Disk Dynamics in IC 1396N", PI: Stan Kurtz (National Mexico University, Mexico);
 GOT: \Fine-structure of the radio cores in 3C 273 and 3C 279 at ultra-high resolution", PI: Tuomas Savolainen (Aalto University, Finland).
Following recommendations of the RPEC, the RadioAstron mission also plans to organize rst test observations of microquasars (PI: Evgeniya Kravchenko, ASC Lebedev).
Among the approved projects, two got rank `A' (the highest priority), eight | rank `B', and six | rank `C'. A total of about 170 co-investigators represent 20 countries. The largest number of co-Is are from Russia, other countries with a high number of co-investigators are the USA, Germany, Australia, the Netherlands, Spain, UK, Italy.

Nikolai Kardashev (nkardash@asc.rssi.ru)
Yuri Kovalev (yyk@asc.rssi.ru)
« Last Edit: 09/13/2014 04:15 PM by Salo »

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #52 on: 09/13/2014 07:22 AM »
http://www.asc.rssi.ru/radioastron/news/news_en.pdf

Astro Space Center
RadioAstron Newsletter
Number 25
12 September 2014
======================
First space-VLBI polarization images with RadioAstron

The RadioAstron Key Science Program on olarization has succeeded in producing the first space-VLBI polarization images from observations of the high-redshift quasar 0642+449 and BL Lacertae.
The RadioAstron observation of 0642+449 was made on March 9-10, 2013 at a wavelength  = 18 cm, with participation of the European VLBI Network (EVN) including the Russian Quasar network and the telescopes in Evpatoria and Green Bank (GBT). The correlated signal between the ground telescopes and the 10-m space radio telescope (SRT) of RadioAstron has been detected on projected baselines of up to 5.9 Earth diameters in length, achieving a resolution of 0.8 mas at the respective fringe-spacing of 420M. A hybrid image of 0642+449 made from the RadioAstron data is shown in Figure 1.
Observations of BL Lac with RadioAstron were performed on November 11, 2013 at 1.3 cm, with an array of ground antennas that includes the European VLBI Network and NRAO's VLBA, adding for a total of 16 antennas. Correlated visibilities between the ground and space antenna have been found up to a projected baseline distance of 6 Earth diameters, yielding a maximum angular resolution of 33 as, the highest achieved to date. Images of BL Lac with RadioAstron are shown in Figure 2, revealing a twisted structure within the innermost 0.2 mas (0.25 parsec) consisting of two components with orthogonal linear polarization.
Both experiments were correlated by the DiFX correlator in Max Planck Institute for Radio Astronomy in Bonn. The estimated instrumental polarization (D-terms) of the space antenna are found to be within 10% at both observed wavelengths of 18 and 1.3 cm, which confirms excellent polarization performance of the SRT. Results from these experiments will be used for further development of RadioAstron polarization imaging.
These observations, recently reported at the COSPAR-2014 assembly in Moscow, represent a milestone in polarimetric space-VLBI observations. They demonstrate the unprecedented polarization and high angular resolution capabilities of the RadioAstron mission. These and continued observations as part of the RadioAstron Polarization Key Science Program are aimed to obtain a better understanding of the innermost regions of AGN jets and their magnetic field structure.

Nikolai Kardashev (nkardash@asc.rssi.ru)
Yuri Kovalev (yyk@asc.rssi.ru)
« Last Edit: 09/13/2014 04:16 PM by Salo »

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #53 on: 09/20/2014 03:42 AM »
http://www.asc.rssi.ru/radioastron/news/news_en.pdf

Astro Space Center
RadioAstron Newsletter
Number 26
19 September 2014
======================
Nearby pulsars B0950+08 and B1919+21

RadioAstron detected a space-Earth interferometric response of individual radio pulses from the pulsar B0950+08 in one of its first experiments. The observations took place on 25 January 2012, in the 92-cm wavelength band, at a maximum distance to the space radio telescope of 300,000 km. The projected interferometer baseline was 220,000 km, providing a record angular resolution of 1/1000 of arcsecond at this wavelength. The space-ground arms of the interferometer were formed by the largest radio telescopes on Earth, at Arecibo (USA), Westerbork (Netherlands) and Effelsberg (Germany).
From data processing and analysis by the original method of structure functions, the observations produced information on the distribution of interstellar plasma. The modulation index of scintillation was found to be about 40%. Theoretical work has shown that such a modulation can be caused by plasma along the line of sight, in the form of two scattering layers and a "cosmic prism." This "prism" is a quite sharp transverse gradient in the plasma distribution.
It deflects radio emission from the pulsar by 1.1 to 4.4 milliarcseconds. The far scattering layer is most likely on the outer boundary of the Local Bubble (a region of low-density gas in neighborhood of the solar system) at a distance of 26 to 170 pc. The near scattering layer is ionized gas at the border of a local molecular cloud, at a distance of 4.4 to 16.4 pc. The spectrum of turbulent density fluctuations in both layers follows a power-law with index  γ1=γ2= 3.00 +- 0.08. This is signi cantly different from the Kolmogorov spectrum, with  γ= 11/3.
These results could be obtained by Space VLBI observations only, because the Fresnel zone of the observed refraction is greater than the diameter of the Earth. The results of this study are published in the Astrophysical Journal (T.V. Smirnova, V.I. Shishov, M.V. Popov, C.R. Gwinn et al., 2014, ApJ, 786, 115): http://dx.doi.org/10.1088/0004-637X/786/2/115 .
Similar results were obtained recently for another nearby pulsar, B1919+21. The interstellar scintillation of PSR B1919+21 is also defined by two screens of plasma inhomogeneities. Two components of scintillation consist of strong diffractive scintillation from a screen located at a distance of 300 pc, and weak scintillation at the layer at a distance 0.7 pc from the Earth. Angular refraction by a cosmic prism located on the distance of 1.7 pc defines the frequency structure of the scintillation. The refractive angle of this prism is 110 mas. The cosmic interferometer resulting from scattering resolves the scattering disk, with size of θdiff =1.5 mas.

Scattering disc substructure in the pulsar B0329+54

The high angular resolution offered by the RadioAstron space-ground interferometer provided the possibility to measure the size of the scattering disk and to estimate the position of the effective scattering screen for the pulsar B0329+54, at an observing frequency of 324 MHz. Observations were conducted in two separate periods: in November 2012 and in January 2014. Observations were supported by the Green Bank Telescope (USA), the Westerbork Synthesis Radio Telescope (the Netherlands), and the 64-m radio telescope at Kalyazin (Russia). Thespace-ground baseline projections varied from 60,000 to 235,000 kilometers during the November 2012 session, and from 15,000 to 120,000 kilometers in January 2014.
Notable visibility amplitudes were detected even at the longest baseline projections of more than 200,000 km, with a values of about 5%, at a 20-σ significance level. The visibility function at the longest spaceround baselines in the delay domain consists of many isolated unresolved spikes. The overall spread of such spikes corresponds to a temporal broadening with a fullwidth at half-maximum of about 7.5 μs. The fine structure of the visibility function in delay is consistent with an amplitude-modulated noise model, and so supports a theoretical picture of randomly scattered rays.
At short space-ground baselines, the distribution of peaks contains a strong central peak. The amplitude of a central peak decreases with the baseline, providing a direct measurement of the size of the scattering disk. This size was found to be 4.6 mas. By comparison of temporal and angular broadening we estimated a distance to the effective scattering screen, and found that it is located nearly halfway to the pulsar. Figure 1 shows the evolution of visibility structure with increasing baseline projection: at short baselines there is a central peak and an extended component; the amplitude of the central peak decreases with the increasing baseline; and only the extended component is present at the longest baselines.

Nikolai Kardashev (nkardash@asc.rssi.ru)
Yuri Kovalev (yyk@asc.rssi.ru)
« Last Edit: 09/20/2014 03:54 AM by Salo »

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #54 on: 04/01/2015 04:54 AM »
http://www.asc.rssi.ru/radioastron/news/news_en.pdf

======================
Astro Space Center
RadioAstron Newsletter
Number 27
31 March 2015
======================
RadioAstron study of galactic and extragalactic water masers

First space-ground detection of extragalactic megamaser: NGC4258 RadioAstron has detected water maser emission from the circumnuclear disk of NGC 4258 galaxy. NGC 4258 (also known as Messier 106) is a spiral galaxy (Seyfert II type) located at the distance of 7.6 Mpc in the constellation Canes Venatici. The H2O Megamaser NGC 4258 is a prototype object with maser spots tracing the accretion disk around a supermassive black hole. The pumping is provided by the in uence of X-ray emission from the center of the galaxy on the disk material. The existence of multiple components is explained by turbulence and
instabilities in the disk. Interferometric signals were obtained with the space radio telescope (SRT) Spektr-R of the RadioAstron project and two ground facilities, the 100-m radio telescope in Green-Bank (USA) and the 32-m radio telescope in Torun (Poland) on 18 December 2014 (Figure 1). The spectrum in the figure shows a 30 minute integration. The extremely small spread among the fringe phases with velocity shows how remarkably thin the actual distribution of masers in the accretion disk is.
The projected baseline length was up to 2 Earth diameters, corresponding to a fringe spacing of about 110 μas. This first extragalactic detection suggests that H2O Megamasers can be successfully studied with RadioAstron and that high resolution SVLBI imaging of H2O Megamasers is possible leading to a detailed analysis of circumnuclear disks in other galaxies.

Water masers in star-forming regions of our Galaxy: Orion KL, W49 N, W3 (H2O)

Successful detection of interferometric fringes from very compact water maser feature associated with the nearest and well studied high-mass star-forming region Orion KL within the RadioAstron key science maser program is reported. Orion KL is a part of the Orion Nebular Cloud Complex and is located around 420 pc from the Sun. Active star formation occurs in this source, accompanied by a powerful maser radiation. Results of previous studies suggest that the compact maser spots are associated with the highly collimated out ow from the accreting young stellar object. The brightness temperature of the detected compact maser spot can exceed 1015 K. Correlated signals were obtained between the space and ground telescopes in two sessions. The 40-m radio telescope in Yebes (Spain), and the 32-m radio telescope in Torun (Poland) took part in the first session on 29 November 2013. The projected baseline length reached 3.5 Earth diameters, corresponding to a fringe spacing of ~63 μas. This corresponds to a linear size of about 3 solar diameters. In the second session (25 December 2013) Orion KL was detected on a baseline to the 26-m radio telescope in Hartebeesthoek (South Africa) with projected baseline of 2 Earth diameters. In both sessions VLSR and line width of the detected maser detail were around 7.3 km/s and ~0.5 km/s, respectively.
Observations of the most luminous water maser source in the Galaxy, star-forming region W49 N, also resulted in a successful fringe detection. W49 N is located at a distance of about 11 Kpc from the Sun in a distant part of the Perseus arm near the solar circle. A correlated signal was obtained on 2014 April, 18 between the space antenna and the 100-m ground radio telescope in Effelsberg (Germany). Projected baselines of the space-ground interferometer in the experiment reached up to about 3 Earth diameters (38,000 km), achieving a fringe-spacing resolution of ~70 μas.
A re-analysis of early RadioAstron observations at the ASC correlator has delivered a positive result for W3 (H2O), the bright water maser complex located ~6 arcseconds to the east of the W3 (OH) ultracompact H II region. A correlated signal was detected between the space antenna and the 100-m ground radio telescope in Effelsberg (Germany) and 40-m radio telescope in Yebes (Spain). Projected baselines of the space-ground interferometer in the experiment reached up to 3.8 Earth diameters (about 48,000 km), achieving a fringe-spacing resolution of ~58 μas.
The collected data on water masers are used to study structure and physical characteristics of the star forming regions in our Galaxy, impose tight limits on the sizes of individual maser spots, estimate brightness temperatures and provide the necessary input for the studies of their pumping mechanisms.

First imaging of water masers with RadioAstron

A RadioAstron imaging of a water maser in the star-forming region W3 IRS5 took place on 17 October 2013 with participation of the European VLBI Network (EVN) including the Russian network "Quasar". Interferometric signals have been detected up to 6 Earth diameters delivering a record angular resolution of 36μas for water masers. This corresponds to linear resolution of ~107 km. The space-ground interferometric image of the bright maser component in W3 IRS5 is shown in the left panel of Figure 2. The ground-only image has an extended structure, resolved out with the space-ground RadioAstron baselines except for a very compact peak visible up to the 6 Earth diameters. A joint analysis of the RadioAstron data and results of Japanese VERA interferometer monitoring allows international team of scientists to identify locations of the most compact maser emission (right panel, Figure 2).

Nikolai Kardashev (nkardash@asc.rssi.ru)
Yuri Kovalev (yyk@asc.rssi.ru)





Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #55 on: 05/28/2015 04:32 PM »
http://www.asc.rssi.ru/radioastron/news/news_en.pdf

======================
Astro Space Center
RadioAstron Newsletter
Number 28
28 May 2015
======================

The RadioAstron AO-3 open science program starts in July 2015

We are happy to report that RadioAstron operations are extended by Roscosmos until the end of 2016.
The second year of the RadioAstron open science program AO-2 is coming to its end in June 2015. Astro Space Center and its Russian and international partners have successfuly performed science experiments within approved AO-2 projects (see the list of projects in the RadioAstron Newsletter No. 24).
Starting from July 2015, the RadioAstron mission will move into the third year of its open program, AO-3 observations will continue until June 2016. The third RadioAstron Announcement of Opportunity has invited proposals of the following two types: the “Key Science Program” (KSP) and “General Observing Time” (GOT). See for details the full set of announcement documents in http://www.asc.rssi.ru/radioastron/ao-3/ao3.html.
All proposal were evaluated by the RadioAstron Program Evaluation Committee (RPEC) which was appointed by the RadioAstron International Science Council (RISC). Results of the evaluation were approved by the RadioAstron project director Nikolai Kardashev. RPEC members for AO-3 are Jason Hessels (U. Amsterdam, the Netherlands), David Jauncey (CSIRO, Australia), Matthew Lister (Purdue U., USA), Mikhail Popov (ASC Lebedev, Russia), Richard Porcas (chair, MPIfR, Germany), Wouter Vlemmings (Chalmers U., Sweden). Below we list 9 accepted projects which have requested observations with RadioAstron during the AO-3 period in their submission order:

• GOT: “Tracing micro-structures of H2O masers with ultimate angular resolution”, PIs: Hiroshi
Imai (Kagoshima U., Japan), Alexey Alakoz (ASC Lebedev, Russia);
• GOT: “Second-epoch Space VLBI visit into core-jet laboratories in the distant Universe”, PI:
Leonid Gurvits (JIVE and TU Delft, the Netherlands);
• KSP: “Space VLBI Survey of AGN at the Highest Angular Resolutions”, PI: Yuri Kovalev (ASC
Lebedev, Russia);
• KSP: “Probing the innermost regions of AGN jets and their magnetic fields”, PI: Jose-Luis
Gomez (IAA, Spain);
• KSP: “Gravitational redshift experiment with RadioAstron”, PI: Valentin Rudenko (SAI MSU,
Russia);
• GOT: “Resolving the milli-parsec jet in the nearby spiral galaxy M81”, PI: Michael Bietenholz
(HartRAO, South Africa; York U., Canada);
• GOT: “Substructure in Pulsar Scattering Disks”, PI: Carl Gwinn (UCSB, USA);
• GOT: “Core shifts with no blending”, PI: Mikhail Lisakov (ASC Lebedev, Russia);
• GOT: “H2O megamasers at high resolution”, PI: Willem Baan (ASTRON, the Netherlans;
ShAO, China).

Among the approved projects, four got rank ‘A’ (the highest priority), two — rank ‘B’, and three — rank ‘C’. A total of about 160 co-investigators represent 20 countries. The largest number of co-Is are from Russia, other countries with a high number of co-investigators are the USA, Germany, Spain, the Netherlands, Australia, Italy, UK, etc.

Nikolai Kardashev (nkardash@asc.rssi.ru)
Yuri Kovalev (yyk@asc.rssi.ru)

The RadioAstron project is led by the Astro Space Center of the Lebedev Physical Institute of the Russian Academy of Sciences and the Lavochkin Scientific and Production Association under a contract with the Russian Federal Space Agency, in collaboration with partner organizations in
Russia and other countries.

To subscribe or un-subscribe to the Newsletter, use: http://asc-lebedev.ru/index2.php?engdep=22

Online Artyom.

Re: Russian RadioAstron (Spectr-R) update
« Reply #56 on: 07/18/2015 10:17 AM »
======================
Astro Space Center
RadioAstron Newsletter
Number 29
18 July 2015
======================

Four years since the launch

Today is the fourth year birth day of the RadioAstron Space Radio Telescope Spektr-R! We
would like to express our congratulations and deep thanks to all the institutions and individuals
involved in the mission’s operations and science.
Several weeks ago AO3 observations have started.

Read more:
"Earth is the cradle of humanity, but one cannot live in a cradle forever." - Konstantin Eduardovich Tsiolkovsky.

Offline Star One

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Re: Russian RadioAstron (Spectr-R) update
« Reply #57 on: 02/02/2016 06:49 PM »
Quote
We present the first polarimetric space VLBI imaging observations at 22 GHz. BL Lacertae was observed in 2013 November 10 with the RadioAstron space VLBI mission, including a ground array of 15 radio telescopes. The instrumental polarization of the space radio telescope is found to be within 9%, demonstrating the polarimetric imaging capabilities of RadioAstron at 22 GHz. Ground-space fringes were obtained up to a projected baseline distance of 7.9 Earth's diameters in length, allowing us to image the jet in BL Lacertae with a maximum angular resolution of 21 μas, the highest achieved to date. We find evidence for emission upstream of the radio core, which may correspond to a recollimation shock at about 40 μas from the jet apex, in a pattern that includes other recollimation shocks at approximately 100 μas and 250 μas from the jet apex. Polarized emission is detected in two components within the innermost 0.5 mas from the core, as well as in some knots 3 mas downstream. Faraday rotation analysis, obtained from combining RadioAstron 22 GHz and ground-based 15 GHz and 43 GHz images, shows a gradient in rotation measure and Faraday corrected polarization vector as a function of position angle with respect to the core, suggesting that the jet in BL Lacertae is threaded by a helical magnetic field. The intrinsic de-boosted brightness temperature in the unresolved core exceeds 3×1012 K, suggesting at the very least departure from equipartition of energy between the magnetic field and radiating particles.

http://arxiv.org/abs/1512.04690

Offline Star One

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Russian RadioAstron (Spectr-R) update
« Reply #58 on: 04/11/2016 06:55 PM »
Astronomers Can't Explain How These Trillion-Degree Quasars Got So Hot

Russian space telescope reveals a quasar whose absurd temperature cannot be explained.

Quote
Astrophysicists have spotted a faraway object that's hotter than any contemporary theory can explain, a discovery that might require scientists rewriting galaxy operation manuals for years to come. The first fruits of these mind-boggling observations were just published by an international group of scientists led by the Russian astrophysicist Yuri Kovalev in the journal Astrophysical Journal Letters.

"I believe that behind this remarkable result lies a new chapter in the exploration of the faraway universe," said Nikolai Kardashev, the head of the Spektr-R (Radioastron) orbital observatory project, which was instrumental in the latest breakthrough.

Quote
In the meantime, the Spektr-R space observatory presses on mission. Launched on a Ukrainian-built Zenit rocket on July 18, 2011, the satellite is about to exceed its five-year manufacturer warranty.Although harsh conditions of space, particularly radiation, are taking their toll on the spacecraft, the flight control team so far has managed to continue a productive scientific mission by switching to backup systems. According to Kovalev, technical issues have not yet degraded the scientific results.

Inspired by the success of Spektr-R, Russian scientists proposed a much more complex space radio telescope known as Spektr-M or Millimetron. The new instrument will be able to register millimeter and sub-millimeter bands of electromagnetic spectrum not only in conjunction with ground-based antennas but also on its own, peering farther into the Universe than any ground-based telescope can. Because of its high cost and many technical hurdles, though, Spektr-M is not expected to blast off into orbit before 2025.

http://www.popularmechanics.com/space/deep-space/a20351/quasar-temperature/
« Last Edit: 04/11/2016 07:02 PM by Star One »

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #59 on: 06/21/2016 05:26 AM »
http://www.asc.rssi.ru/radioastron/news/news_en.pdf

======================
Astro Space Center
RadioAstron Newsletter
Number 30
20 June 2016
======================
The RadioAstron extension and AO-4 open science program start in July 2016

We are happy to report that RadioAstron operations are extended by Roscosmos until the end of 2018.
The third year of the RadioAstron open science program AO-3 is coming to its end in July 2016.  Astro Space Center and its russian and international partners have successfuly performed science experiments within approved AO-3 projects (see the list of projects in the RadioAstron Newsletter No. 28).
Starting from July 2016, the RadioAstron mission will move into the fourth year of its open program, AO-4 observations will continue until June 2017.  The fourth RadioAstron Announcement of Opportunity has invited proposals of the following two types:  the \Key Science Program" (KSP) and \General Observing Time" (GOT). See for details the full set of announcement documents in http://www.asc.rssi.ru/radioastron/ao-4/ao4.html .
All proposal were evaluated by the RadioAstron Program Evaluation Committee (RPEC) which was appointed by the RadioAstron International Science Council (RISC). Results of the evaluation were approved by the RadioAstron project director Nikolai Kardashev.  RPEC members for AO-4 are Jason Hessels (U. Amsterdam, the Netherlands), David Jauncey (CSIRO, Australia), Matthew Lister (Purdue U., USA), Mikhail Popov (ASC Lebedev, Russia), Richard Porcas (chair, MPIfR, Germany), Wouter Vlemmings (Chalmers U., Sweden).  Below we list 11 accepted projects which have requested observations with RadioAstron during the AO-4 period in their submission order:
• GOT: \Mapping and monitoring of cores of H2O masers with ultimate angular resolution", PIs: Hiroshi Imai (Kagoshima U., Japan), Alexey Alakoz (ASC Lebedev, Russia);
• GOT: \Angular diameters of pulsar scattering disks and the distribution of interstellar plasma fluctuations", PI: Mikhail Popov (ASC Lebedev, Russia);
• GOT: \Second-epoch Space VLBI visit into core-jet laboratories in the distant Universe (continued)", PI: Leonid Gurvits (JIVE and TU Delft, the Netherlands);
• GOT: \The nuclear structure of 3C84 with Space VLBI { II epoch", PI: Gabriele Giovannini (Bologona U. and INAF, Italy);
• GOT: \H2O megamaser sources at high resolution", PI: Willem Baan (ASTRON, the Netherlans; ShAO, China).
• KSP:  \Probing  the  innermost  regions  of  AGN  jets  and  their  magnetic   elds",  PI:  Jose-Luis Gomez (IAA, Spain);
• KSP: \Monitoring of the brightest AGN cores with RadioAstron", PI: Yuri Kovalev (ASC Lebedev, Russia);
• GOT: \A milli-arcsecond gravitational lens in S5 B0615+820?", PI: Eduardo Ros (MPIfR, Germany; U. Valencia, Spain);
• GOT:  \Resolving  the  Jet-Collimation  Region  of  the  NGC1052  Twin-Jet  System",  PI:  Anne-Kathrin Baczko (MPIfR, Germany);
• KSP: \Gravitational redshift experiment with RadioAstron", PI: Valentin Rudenko (SAI MSU, Russia);
• GOT: \Joint Pulsar { AGN Ground-Space VLBI", PI: Vladimir Soglasnov (ASC Lebedev, Russia).
Among the approved projects, four got rank `A' (the highest priority), three | rank `B', and four | rank `C'. A total of about 155 co-investigators represent 19 countries.  The largest number of  co-Is  are  from  Russia,  other  countries  with  a  high  number  of  co-investigators  are  the  USA, Germany, Spain, the Netherlands, Australia, Italy, etc.

RadioAstron science results

We are happy to note the growing number of RadioAstron publications ( http://www.asc.rssi.ru/radioastron/publications/publ.html )  as  well  as  many  reports  on  science  meetings  including the recent \Dissecting the Universe" workshop in Bonn ( https://events.mpifr-bonn.mpg.de/indico/event/4/timetable/ ) and \Blazars through Sharp Multi-Wavelength Eyes" in Malaga ( http://jets2016.iaa.es/content/program ).
On June 20-22, 2016, many colleagues gather in Moscow to celebrate the 100 years anniversary of Iosif Shklovsky at the Shklovsky-100 symposium ( http://shklovsky100.asc.rssi.ru/index.php/en/programm ).

Nikolai Kardashev (nkardash@asc.rssi.ru)
Yuri Kovalev (yyk@asc.rssi.ru)

The RadioAstron project is led by the Astro Space Center of the Lebedev Physical Institute of the Russian Academy of Sciences and the Lavochkin Scientific and Production Association under a contract with the Russian Federal Space Agency, in collaboration with partner organizations in Russia and other countries.

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