Author Topic: Delta IV-H - Parker Solar Probe - SLC-37 - Aug 12, 2018  (Read 127124 times)

Offline FutureSpaceTourist

  • Senior Member
  • *****
  • Posts: 6839
  • UK
    • Plan 28
  • Liked: 6726
  • Likes Given: 2091
Weather forecast has worsened a bit to 70% GO and 60% on delay days:

Quote
Launch day overall probability of violating weather constraints: 30%
Primary concern(s): Attached and Detached Anvil Clouds, Cumulus Clouds

24-hour delay overall probability of violating weather constraints: 40%
Primary concern(s): Attached and Detached Anvil Clouds, Thick Cloud Layers

48-hour delay overall probability of violating weather constraints: 40%
Primary concern(s): Attached and Detached Anvil Clouds, Thick Cloud Layers

Online Rondaz

  • Full Member
  • ***
  • Posts: 378
  • Liked: 121
  • Likes Given: 105
Parker Solar Probe: T Minus 2 days

Did you know NASA has several definitions for a countdown?!?  “T Minus”, “L Minus”, and NASA even sometimes uses “E Minus”. What do they all mean and why do we have them? NASA Launch Services Program at Kennedy Space Center can help with the translations.
NASA’s Launch Services (LSP) is responsible for launching uncrewed rockets delivering spacecraft that observe the Earth, visit other planets and explore the universe. They have also had a significant hand in getting Parker to where it is today.

NASA’s LSP team also have a very insightful twitter feed that was a great source at explaining the need for different countdown definitions. In one particular tweet by the LSP team made in 2015, they explained the meaning behind “L Minus” as:

"L Minus" time is different from "T Minus" time."L minus" indicates how far away we are from actual liftoff& doesn't include built-in holds.
But, even more insightful is the conversation that has continued in this thread. And so if the explanation above still has you confused, like it did me, then a 30 seconds youtube clip by NASA LSP chief engineer, James Wood, is more likely to nail down the meaning for you. What was most insightful to me was when James stated,

“T Minus time is really a sequence of events, so we order the events of how we conduct a launch count in a very specifically orderly manner”

“T times which really aren’t times at all, they can be extended or contracted as necessary to keep the launch moving and stay within the window”

Then what is “E Minus” for? Well it turns out that T and L are used for launching a rocket (with the spacecraft inside).  But when a spacecraft is already in space, performing its ordinary mission, an “E Minus” time can be used to identify a countdown to a specific event. According to Tim Larson,  EPOXI mission project manager as NASA’s JPL, “E Minus” stands for Encounter.

So for the case of EPOXI, the encounter was for comet Hartley 2. Assuming this method holds true for other missions, New Horizons mission, that recently flew by Pluto to take the wonderful picture we have today, would have also employed a similar “E Minus” sequence for when the spacecraft was traveling towards the closest approached of the planet.

So, has this explanation helped your understanding for the Parker Launch happening in a few days? or is there something else that you want explanations for, in preparation of the launch? if so let us know in the comments below.

Offline Kim Keller

  • Full Member
  • ****
  • Posts: 963
  • Not OldSpace, Not NewSpace - I'm ALLSpace
  • Location: Wherever the rockets are
  • Liked: 2366
  • Likes Given: 114
"L Minus" time is different from "T Minus" time."L minus" indicates how far away we are from actual liftoff& doesn't include built-in holds.

Clarification: "L-" times DO include built-in hold time (BIHs), and reflect the actual time remaining until launch (barring unexpected holds). "T-" times don't. The "T-" time clock stops during built-in holds, the "L-" clock continues to tick, even through BIH's.
« Last Edit: 08/09/2018 12:43 AM by Kim Keller »

Offline worldtimedate

  • Full Member
  • ***
  • Posts: 344
    • World TimeDate
  • Liked: 26
  • Likes Given: 8
Delta IV Parker Solar Probe

According to ULA site and ULA Twitter page, Parker Solar Probe Launch time has been tentatively scheduled at 3:33 AM EDT at the beginning of a 65-minute launch window. ULA has also published a toll free ULA launch hotline at 1-877-852-4321 at its website.

Launch Info : [ https://twitter.com/ulalaunch/status/1027308460998885378?p=v ]

Delta IV Heavy will use a powerful third stage supplied by Northrop Grumman Innovation Systems to augment the launcher's capability.

Quote
ULA website further states that Due to the extremely high energy required for this mission, the Delta IV Heavy's capability will be augmented by a powerful third stage provided by Northrop Grumman Innovation Systems.

--- [ --- ]

Offline worldtimedate

  • Full Member
  • ***
  • Posts: 344
    • World TimeDate
  • Liked: 26
  • Likes Given: 8
This is the first time that Delta IV Heavy is using a third stage, meant to augment its capability.

Delta IV Heavy Capability to be Augmented by Orbital ATK Third Stage

Quote
Orbital ATK (NYSE: OA) is teamed with United Launch Alliance (ULA) to launch NASA s Solar Probe Plus (SPP) mission on ULA s Delta IV Heavy rocket. A fully integrated third stage provided by Orbital ATK will give the spacecraft the high-energy boost needed to send it on its mission to study the Sun s outer atmosphere.

Quote
Orbital ATK's third stage leverages flight-proven inertial navigation, avionics, attitude control and separation systems used on the company's Pegasus, Minotaur and Minotaur-C launch vehicles. The venerable STARTM 48BV rocket motor, which traces its roots back to the 1980s, will provide the propulsion. The STAR 48 motor series has logged more than 130 successful missions.

One of Orbital ATK's strengths is providing new launch capabilities that leverage flight-proven subsystems, said Ron Grabe, President of Orbital ATK s Flight Systems Group. We are proud to team with ULA to augment the Delta IV Heavy for this very challenging mission.

Quote
After separating from the launch vehicle's second stage, Orbital ATK's third stage motor will ignite and accelerate the SPP spacecraft, making it one of the fastest man-made objects in history. During the motor's nominal burn time of 81 seconds, Orbital ATK's flight computer and guidance control system will guide the SPP observatory on its way to an elliptical orbit around the Sun. The observatory, using several gravity assists from Venus, will ultimately pass within 10 solar radii of the Sun, many times closer to the sun than the planet Mercury.

--- [ --- ]

Offline FutureSpaceTourist

  • Senior Member
  • *****
  • Posts: 6839
  • UK
    • Plan 28
  • Liked: 6726
  • Likes Given: 2091
Posted by NASA

Online Rondaz

  • Full Member
  • ***
  • Posts: 378
  • Liked: 121
  • Likes Given: 105
Parker Solar Probe Proceeds Toward Launch Aug. 11

The Parker Solar Probe mission and launch teams today concluded a successful Launch Readiness Review. There are no technical issues being worked at this time. Teams are proceeding for liftoff on Saturday, Aug. 11, at 3:33 a.m. EDT. On a United Launch Alliance Delta IV Heavy rocket with NASA’s Parker Solar Probe.

Parker Solar Probe will provide unprecedented information about our Sun, where changing conditions can spread out into the solar system to affect Earth and other worlds. The spacecraft will fly directly into the Sun’s atmosphere where, from a distance of – at the closest approach — approximately 4 million miles from its surface, the spacecraft will trace how energy and heat move through the Sun’s atmosphere and explore what accelerates the solar wind and solar energetic particles.

Meteorologists with the U.S. Air Force 45th Space Wing are predicting a 70 percent chance of favorable weather on launch day. Primary weather concerns are anvil clouds and cumulus clouds.

Offline ChrisGebhardt

  • Assistant Managing Editor
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 7000
  • ad astra scientia
  • ~1 AU
  • Liked: 5789
  • Likes Given: 724
Parker pre-launch briefing coming up at 1pm EDT (17:00 UTC).
« Last Edit: 08/09/2018 04:32 PM by ChrisGebhardt »

Offline ChrisGebhardt

  • Assistant Managing Editor
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 7000
  • ad astra scientia
  • ~1 AU
  • Liked: 5789
  • Likes Given: 724
Spacecraft separation will be at MET 43mins 18secs.

Offline ChrisGebhardt

  • Assistant Managing Editor
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 7000
  • ad astra scientia
  • ~1 AU
  • Liked: 5789
  • Likes Given: 724
Dr. Parker just walked in to the briefing to listen to it to stand ovation.

Offline ChrisGebhardt

  • Assistant Managing Editor
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 7000
  • ad astra scientia
  • ~1 AU
  • Liked: 5789
  • Likes Given: 724
Closest approach is about 4 million miles - under 5% the average distance of Earth from the Sun.
« Last Edit: 08/09/2018 05:02 PM by ChrisGebhardt »

Offline ChrisGebhardt

  • Assistant Managing Editor
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 7000
  • ad astra scientia
  • ~1 AU
  • Liked: 5789
  • Likes Given: 724
Mission has been 60 years in the making.  We've had to wait so long because our technology wasn't sophisticated and advanced enough to support mission.

Offline ChrisGebhardt

  • Assistant Managing Editor
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 7000
  • ad astra scientia
  • ~1 AU
  • Liked: 5789
  • Likes Given: 724
430,000 mph is about max speed of Parker Solar during close approach.

Offline ChrisGebhardt

  • Assistant Managing Editor
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 7000
  • ad astra scientia
  • ~1 AU
  • Liked: 5789
  • Likes Given: 724
PSP will take first up-close images of Sun's corona.

Offline ChrisGebhardt

  • Assistant Managing Editor
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 7000
  • ad astra scientia
  • ~1 AU
  • Liked: 5789
  • Likes Given: 724
Heat shield took a decade to design and 18 months to build.  It's made of Carbon-Carbon panels -- the same material the protected the Space Shuttle's nose caps and Wing Leading Edges during atmospheric reentry for over 30 years.

Offline ChrisGebhardt

  • Assistant Managing Editor
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 7000
  • ad astra scientia
  • ~1 AU
  • Liked: 5789
  • Likes Given: 724
There will be 16-mins of round-trip light-time communications delay with Parker as it dives toward the sun and comm blackout periods when it dips behind the sun (as seen from Earth).

Offline Mapperuo

  • Assistant Webmaster
  • Administrator
  • Full Member
  • *****
  • Posts: 1664
  • Yorkshire
  • Liked: 495
  • Likes Given: 65
- Aaron

Offline worldtimedate

  • Full Member
  • ***
  • Posts: 344
    • World TimeDate
  • Liked: 26
  • Likes Given: 8
Parker Solar Probe website of the John Hopkins University of Applied Physics Lab has already started showing the countdown for the lift-off which is scheduled at 3:33AM EDT on August 11.

Parker Solar Probe - Jhuapl.edu
http://parkersolarprobe.jhuapl.edu/

Parker Solar Probe | NASA
https://www.nasa.gov/content/goddard/parker-solar-probe

NASA Live: Parker Solar Probe Launch
https://www.nasa.gov/nasalive

Parker Solar Probe Briefings and Events | NASA
https://www.nasa.gov/press-release/parker-solar-probe-briefings-and-events

Parker Solar Probe - Mission News | NASA
https://www.nasa.gov/content/goddard/parker-solar-probe-mission-news

Offline worldtimedate

  • Full Member
  • ***
  • Posts: 344
    • World TimeDate
  • Liked: 26
  • Likes Given: 8
It's Surprisingly Hard to Go to the Sun

Quote
The Sun contains 99.8 percent of the mass in our solar system. Its gravitational pull is what keeps everything here, from tiny Mercury to the gas giants to the Oort Cloud, 186 billion miles away. But even though the Sun has such a powerful pull, it's surprisingly hard to actually go to the Sun: It takes 55 times more energy to go to the Sun than it does to go to Mars.

Why is it so difficult ? The answer lies in the same fact that keeps Earth from plunging into the Sun: Our planet is traveling very fast - about 67,000 miles per hour - almost entirely sideways relative to the Sun. The only way to get to the Sun is to cancel that sideways motion.

Quote
Since Parker Solar Probe will skim through the Sun's atmosphere, it only needs to drop 53,000 miles per hour of sideways motion to reach its destination, but that's no easy feat. In addition to using a powerful rocket, the Delta IV Heavy, Parker Solar Probe will perform seven Venus gravity assists over its seven-year mission to shed sideways speed into Venus' well of orbital energy. These gravity assists will draw Parker Solar Probe's orbit closer to the Sun for a record approach of just 3.83 million miles from the Sun's visible surface on the final orbits.

Quote
Though it's shedding sideways speed to get closer to the Sun, Parker Solar Probe will pick up overall speed, bolstered by Sun's extreme gravity - so it will also break the record for the fastest-ever human-made objects, clocking in at 430,000 miles per hour on its final orbits.

Offline SciNews

  • Full Member
  • ***
  • Posts: 379
  • Romania
  • Liked: 357
  • Likes Given: 5
recap of integration activities

Tags: