Space Stuff and Launch Info

[berkeman]

That was pretty interesting watching the other 2 engines gimbal to maintain balance when the first engine shut off. It looked like they made it to the stops a couple of times before getting full balance back. Did it seem like that to you?

Also, it seemed like there was some transient fire in the engine compartment view a couple of times, but they didn't seem to result in anything catastrophic. Are those normal?

 

[mfb]

I wouldn't call it "normal" but it happened before. A bit of fire seems to be acceptable.

The fast and strong gimbaling surprised me as well but it might have some deeper purpose.

 

[Dullard]

My take (purely speculating):

Those were commanded shutdowns. How the system responds to the 'unexpected' loss of an engine was probably one of the items on the test checklist.

The fires are really just a test artifact - a 'shutting down' rocket engine needs to stay fuel-rich. If that shutdown occurs in an atmosphere containing lots of ambient oxygen (and next to a running engine), some fire is probably unavoidable.

 

[Dullard]

Quite a 'window-rattler' last night. My dog hates Eastward trajectories.

 

[Stavros Kiri]

Today (Mon. Dec. 21, 2020 - Winter Solstice) is the big conjunction of Jupiter and Saturn. Don't miss it! (e.g. 45' after sunset) ... if you're not under clouds ... [It looks like a Christmas Star]
Also DO NOT miss to check out today's Google's Doodle! ... It's fun and hilarious!
https://www.google.com (for Dec. 21, 2020)

See also (today Dec. 21, or later the archive for this day):
https://spaceweather.com

 

[Stavros Kiri]

Today (Mon. Dec. 21, 2020 - Winter Solstice) is the big conjunction of Jupiter and Saturn. Don't miss it! (e.g. 45' after sunset) ... if you're not under clouds ... [It looks like a Christmas Star]
Also DO NOT miss to check out today's Google's Doodle! ... It's fun and hilarious!
https://www.google.com (for Dec. 21, 2020)

See also (today Dec. 21, or later the archive for this day):
https://spaceweather.com

Here is the time-fixed links:
1)

2)
https://spaceweather.com/archive.php?view=1&day=21&month=12&year=2020

 

[mfb]

Rideshares are really taking off this year. Literally as well.

The spaceflight year starts January 10, with the second attempt of LauncherOne to reach orbit. On board: 10 cubesats
Just 4 days later SpaceX launches its first dedicated rideshare mission with close to 100 small satellites.
Also planned for January (but might be delayed) is the maiden flight of Firefly Alpha. On board: ~35 satellites
SpaceX has another rideshare mission planned, not earlier than February but no launch date yet.
March 20: Soyuz flying a rideshare mission with ~25 satellites
Arianespace doesn't want to be left out: A Vega mission is planned for not earlier than March, carrying several satellites (number to be determined).
Add several missions with a large spacecraft where smaller satellites are carried along.

That's just the first quarter.

 

[mfb]

Gwynne Shotwell talks about selling flight-proven rockets, Starship

Interesting insight in how SpaceX sells launches.

* You buy the service, not the rocket. Which booster to use where is up to SpaceX unless you have special requests.
* Making people accept reused boosters was easier than selling Falcon 1 and Falcon 9. At that time the company had a track record of getting things done already.
* They already sold contracts where it is up to SpaceX if they fly with Starship or Falcon 9. This is going far beyond the first point: You don't even know which rocket type you will fly with. It gives SpaceX flights for Starship while the customers can be assured they will go to space even if Starship is delayed - because Falcon 9 is available.

If you send a package from A to B you normally don't ask for a specific airplane to do the delivery either. You care about the arrival time, proper handling in between and similar, but not about the exact route. Looks like SpaceX wants to go in the same direction.

 

[Tom.G]

LIVE HOT-FIRE TEST OF ARTEMIS

Live coverage starts at 4:20p.m. US EST, Saturday, Jan. 16 on NASA tv: https://www.nasa.gov/live

See article at:
https://www.nasa.gov/press-release/...-rocket-core-stage-for-artemis-moon-missions/

 

[mfb]

First flight of the New Shepard capsule that's designed to fly crew, hopefully this year: T-12 minutes + x
Livestream

 

[berkeman]

First flight of the New Shepard capsule that's designed to fly crew, hopefully this year: T-12 minutes + x
Livestream

Interesting flight; thanks for the heads-up.

That was a strange vertical oscillation in the telescopic camera's tracking of the ascending rocket. Have you seen that oscillation in previous launches? They need to fix that, IMO. It was pretty annoying. I loved the view from the plane/helicopter/drone/whatever it was as the rocket screamed past it early in the launch. Do you know what they used?

 

[mfb]

I would expect a drone but I don't know.
The tracking could get improved.

 

[mfb]

LIVE HOT-FIRE TEST OF ARTEMIS

Live coverage starts at 4:20p.m. US EST, Saturday, Jan. 16 on NASA tv: https://www.nasa.gov/live

See article at:
https://www.nasa.gov/press-release/...-rocket-core-stage-for-artemis-moon-missions/

It fired for one minute out of the planned 8 minutes and then shut down unexpectedly. Based on the livestream it sounds like the problem was coming from the thrust vector control of one engine, i.e. its ability to change the direction of the exhaust to steer the rocket.
This could be anything from a minor fix not affecting the schedule to something that will need a repetition of the green run test and another year or two.

 

[mfb]

Not clear yet how NASA will proceed.

https://www.space.com/nasa-sls-megarocket-artemis-1-engine-test-fire

Repeating the static fire test would need at least a month or so. Possibly longer if things need to be repaired or exchanged. It's possible to swap engines if needed - they have several more in storage. This is probably the safest option in terms of testing that everything works, but it's also one that comes with large risks for the launch schedule.
It's possible that they move the core stage to the launch site and do a shorter static fire there.
It's possible that they are confident they can go ahead with the launch without extra tests - if (a) the cause is understood and fixed and (b) the 1 minute static fire produced enough data to be confident about an 8 minute burn. They didn't get to the thrust vectoring test, so that's one interesting dataset missing for sure.

They started stacking the solid rocket booster elements a few weeks ago. As soon as you start stacking them, the fuel inside of them slowly redistributes. NASA knows that the boosters are good for 12 months after the stacking begins - that would force a launch in 2021. It's possible that the boosters are good for longer, the 12 months were a conservative estimate - but NASA might have reasons to avoid operating solid rocket boosters outside their specifications.Edit: Success of LauncherOne at its second attempt. The first liquid-fuel air-launched rocket.

 

[mfb]

Green Run Update: Data and Inspections Indicate Core Stage in Good Condition

After analyzing initial data, the team determined that the shutdown after firing the engines for 67.2-seconds on Jan.16 was triggered by test parameters that were intentionally conservative to ensure the safety of the core stage during the test.

The engines would have kept firing during an actual launch.
It still means several test items could not be completed, so NASA considers rerunning the test. Nothing is broken at least.

 

[mfb]

arstechnica has image of the assembled Transporter-1 mission. It looks very chaotic with payloads from so many different customers on board. It will launch 143 satellites, breaking the previous record of 104 in a single launch.
The planned launch is in ~10 hours from now. Deployment of the satellites will take over an hour.

 

[mfb]

arstechnica has image of the assembled Transporter-1 mission. It looks very chaotic with payloads from so many different customers on board. It will launch 143 satellites, breaking the previous record of 104 in a single launch.
The planned launch is in ~10 hours from now. Deployment of the satellites will take over an hour.

Edit: Success. At least for everything deployed from Falcon 9 directly. Getting information about every secondary deployment (Falcon 9 deploys X which later deploys X1, X2, ...) is difficult.

 

[mfb]

Green Run Update: NASA Proceeds With Plans for Second Hot Fire Test
As early as the fourth week in February. This is almost a month of delay in a schedule that's already very tight. It is within the margins they had, but now every delay will threaten the launch. They can't push the launch date much: The solid rocket boosters have an expiration date.

 

[mfb]

It's Mars season!
The Emirates Mars Mission will arrive on Tuesday, the Chinese Tianwen-1 will arrive on Thursday, and the American Perseverance will arrive Thursday next week (Feb 18).

Perseverance (rover+helicopter) is on a trajectory to land directly, so arrival data is landing date. The Chinese mission will go into an orbit around Mars first, its lander/rover are planned to land in April. The UAE mission is an orbiter.

 

[Borg]

American Perseverance will arrive Thursday next week (Feb 18)

I'm looking forward to seeing if my wife and I land safely.

Spoiler

https://mars.nasa.gov/resources/24877/send-your-name-placard-attached-to-perseverance/

 

[Stavros Kiri]

I'm looking forward to seeing if my wife and I land safely.

Spoiler

https://mars.nasa.gov/resources/24877/send-your-name-placard-attached-to-perseverance/

God Speed!

 

[berkeman]

and the American Perseverance will arrive Thursday next week (Feb 18).

Very cool animation of the landing! I like how in the final powered phase the rocket assembly seems to be actively looking at the terrain it is heading for and maneuvering to get to the safest/flatest spot.

 

[Stavros Kiri]

It's landing day on Mars! NASA's Perseverance rover will touch down on the Red Planet today

 

[hutchphd]

I am such a Nerd...Jumping up and down in front of the monitor. Those JPL folks are pretty impressive practitioners. Science strikes again.

 

[berkeman]

Interesting article that mentions some of the things the lander did to avoid the hazards in the landing area:

https://www.cnn.com/2021/02/18/world/mars-perseverance-rover-landing-scn-trnd/index.html

 

[mfb]

Here is the link between these two images. I added the approximate landing spot in red in the upper image.

 

[Oldman too]

Too cool not to post.

 

[mfb]

Can't wait for Ingenuity to fly. Unfortunately we'll have to. It is attached to the underside of the rover and deployment is only planned for April/May. Then the rover will drive another 100 meters before Ingenuity makes a first flight.
First flight anywhere outside Earth!

 

[mfb]

Second SLS test fire on Thursday
They decided to aim at a full-duration test again, i.e. eight minutes, at least four minutes are needed for the critical tests.

The solid rocket boosters have been stacked, the 1 year countdown to launch is ticking and the schedule is tight - if something delays the launch further they might need to open and inspect the boosters again, which would immediately extend the delay.

 

[Klystron]

Apropos space stuff, the New York Times (again) predicts the final handover of building large rockets for space exploration from NASA to commercial enterprise.

The article contains as much politics as science, as expected. The blithe conclusion that NASA simply combine mission with the so-called Space Force; that is, become a minor arm of the military, flies in the face of all that NASA stands for as a bulwark of cooperative peaceful scientific exploration.

Having served roughly a decade in both the USAF and at NASA, their missions remain starkly different even as technology converges. Certainly NASA contains origins in the military but their goals -- peaceful exploration versus defense -- should not be conflated for obvious and terrible reasons. NASA, originally NACA, was precisely created separately from the USAF, actually Aerospace Force, to avoid militarizing space.

Simplicity should never embrace stupidity.