Thread: SpaceX - On to Mars

It looks like fuel was venting under the rocket then the igniters did their thing.

Originally Posted by Topper

It looks like fuel was venting under the rocket then the igniters did their thing.

Yes, the big question is why was there that much methane? It should have been only a very small amount.

Explanation of autogenous pressurization. Tanks of rockets need to be pressurized for stability and to provide head pressure for the engines to operate. Usually helium is used for the purpose. But helium is expensive, the cost can easily exceed the cost of the propellant. Also Starship is to go to Mars and come back. Mars has no helium. So they chose autogenous pressurization. Pressurize the oxygen tank with hot gaseous oxygen, the methane tank with hot gaseous methane. The gas is heated by the firing engine and moves to the tank through pipes. A very tricky system. Some early Starship tests failed for not performing as planned.

So a 20 second firing to prove the system working is a very important step.

Occupy Mars

Inspirational SpaceX YouTube video with a few interesting sequences.

The size of it.


When they do all the weight measurements, do they allow for the weight of the balls of the people strapped on top of the thing?

Yesterday they did the biggest static fire of the booster so far. 14 out of 33 engines. It was a full success, the burn lasted for the planned duration. The thrust of this test, with less than half the engines, already exceeds the launch thrust of Saturn V and the Shuttle. The Soviet N1, their intended Moon rocket, had more thrust but never launched successful and was canceled after several early explosions that all destroyed the launch pad. The late Soviet Energiya rocket, also had more thrust. It launched 2 times, first a failure, second a success. Then the program ended because of extremely high cost and the coming end of the Soviet Union.

Unlike other launch pads SpaceX does not pour a huge amount of water under the rocket. They spray out a fine mist of tiny droplets. Much more efficient in water use but unclear yet if that's good enough. Watch for the mist before the engines ignite. There was a little damage to the pad. If they want a high launch cadence they will need to improve the pad infrastructure more. They do constant improvements all the time.



More tests coming up. They still hope for orbital launch this year, dependent on how well the test sequence goes.

On every test of this kind NASA teams of the NASA HLS, human landing system for the Moon, are present. They are very pleased with the progress. No comments on the latest tests so far, but they should be pleased again.

An interesting critique of Elon Musk's Mars project.

Originally Posted by happynz

An interesting critique of Elon Musk's Mars project.

It seems that you have accidentally discovered a way to rid earth of the most pernicious, wealthy nut jobs that currently exist. Well done.

She's on the way.

A quite interesting video about the physics of a flight to Mars. The theme is Starship to Mars but actually most of it is general information, not Starship specific.

After a long time with small steps for Starship, yesterday a big step forward. A full wet dress rehearsal with the full Starship stack, Starship on top of the Booster, both fully fueled with methane and liquid oxygen(LOX). Previous tanking tests were using liquid nitrogen to reduce risk. For engine hot fire tests they filled in only small amounts of methane and LOX, as needed for the test duration. For that much propellant some of the people in nearby Boca Chica village were evacuated, in case of explosion.

Video of the fully fueled Starship from SpaceX on twitter.

https://twitter.com/SpaceX/status/1617676629001801728

Starship completed its first full flight-like wet dress rehearsal at Starbase today. This was the first time an integrated Ship and Booster were fully loaded with more than 10 million pounds of propellant

Today’s test will help verify a full launch countdown sequence, as well as the performance of Starship and the orbital pad for flight-like operations

Video copied to YouTube by someone. With very annoying background music.



Starship will be taken down to be prepared for first orbital flight.

Some more engine tests for the booster, including the first test firing of all 33 booster engines. A hell of a lot of power.

Orbital flight maybe late February, more likely March. NASA HLS team is closely watching because successful flight of Starship is needed for their Artemis Moon landing program. Starship will be the Moon lander for their astronauts.

BTW, a reddit user calculated the effect of cooling on the Starship booster. Getting so cold the booster shrinks by ~40cm in height.

Originally Posted by Takeovers

Some more engine tests for the booster, including the first test firing of all 33 booster engines. A hell of a lot of power.

Do you suppose they'll pull the launch mount out of the ground?

Originally Posted by Topper

Do you suppose they'll pull the launch mount out of the ground?

Probably not that. There is an insane amount of deep piling in the ground which is mostly mud, clay and gravel. Question is how much of concrete base rework will be needed after the static fire.

Just found an excellent time lapse of the whole tanking process, over 1 hour in a few seconds. NASAspaceflightforum has excellent high quality video coverage.

Wet Dress Rehearsal at Starbase #shorts - YouTube

^ Thanks TO!