- Jun 12, 2014
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Landings were underrated. Sometimes you could even catch a glimpse during the day as it glided in, depending on trajectory. Sonic boom was so loud...If you have never been to a launch in person, you really have no understanding of how awesome the power is of even a small rocket. My dad would get the NASA causeway passes - as close as the common man could get - for shuttle launches. Never got tired of them, especially the night launches. It was just like watching a sunrise.
Landings were underrated. Sometimes you could even catch a glimpse during the day as it glided in, depending on trajectory. Sonic boom was so loud...
SpaceX, using a Falcon Heavy, did put a Tesla in solar orbit so there's that.@ThreatMatrix has SpaceX launched any longer term, deep space type satellites yet? I assume ULA is still spitting out heavier payloads due to size constraints on the Falcon 9. Would be nice for SLS to finally become viable to help create some competition to drive greater innovation.
SpaceX, using a Falcon Heavy, did put a Tesla in solar orbit so there's that.
But glad you asked.
Rockets are classified by how much they can lift to LEO.
Heavy: 20 - 50 metric tons
Super Heavy: More than 50 Metric tons
If SLS is ever built it will be capable of 95 M tons. A block 2 is planned but not funded for 130 M tons.
SaturnV could lift 140 M tons.
ULA flies the
Delta IV 28.7 metric tons
Atlas V 20.5 metric tons
and soon
Vulcan 27.2 metric tons
SpaceX is currently flying
Falcon 9 Block 5 - 22.8 Mt expendable 16.8 Mt reusable
Falcon Heavy - 63Mt expendable something less than 50Mt reusable. Falcon Heavy can do whatever ULA does.
But SpaceX plans to replace the Falcon 9 and Falcon Heavy with Starship Super Heavy. The Starship spacecraft that sits on the SH has 4 configurations: Crew, Cargo (with a clam shell cargo door), tanker, and now the "Moon"ship. They'll launch the remainder of Starlink and customer payloads with the cargo configuration.
Starship Super Heavy will be capable of 100 M tons. But since the Starship spacecraft can be refueled it can do something no one else can. It can deliver 40-50 M tons to the moon, Mars and outer planets. The others can only deliver a few M tons.
Deep space satellites get there under their own power and gravity assist. The second spec that rockets are classified by is how much payload they can get to GTO. GTO is an elliptical orbit. When the satellite reaches the apogee it begins to do burns on it's own to circularize and/or increase it's orbit. If it wants to travel beyond the inner planets it uses gravity assists (usually).
Extra credit:
So. Spaceships get to the moon and mars by something called a Hohmann Transfer Orbit. That is they increase the apogee of their earth orbit until reaches the orbit of the planet they are traveling to. In order to increase your orbit you burn in the direction you are traveling (prograde). This increases the height of the orbit on the opposite side so you end up with an elliptical orbit. If you want to circularize then when you get to apogee you do another prograde burn and that raises the perigee. When we go to the moon we start in a LEO. The burn they call the Trans Lunar Injection (TLI) is just the burn raising the apogee (Hohmann transfer). Of course you have to time it so that you arrive at the same time as the moon.
You also may not be in the proper plane. We launch at the cape which gives the orbit a 23 degree inclination and the moon is close to zero. So you have to do a plane change. That is done by burning perpendicular halfway between apogee and perigee. You wanna do that using the least amount of fuel. I can't remember if that's when the orbit is small or large.
I can't remember if that's when the orbit is small or large.
I know.Maybe you could some research and find out then. You know, like actually bring something constructive to the thread.
Yep. There's some challenges with moon landing. They've added engines towards the top. You can see three ovals in some pictures. Presumably those would be Dracos but could be something else. By putting them up high that helps with not kicking up so much regolith on landing, which is a concern. The Starship is very bottom heavy. Like the boosters it's why they can retro-propulsively land on a barge. And the landing legs on Starship will be self leveling.Elon says the Dragon could land with the Dracos but the old stand-by is good enough. The original plan was for a Dragon to land on the Moon, they would need the Draco's for that but when they decided to go with the BFR, everything changed.
I've got big concerns about how they will land the Starship on the Moon, seems to me the Regolith is just too unstable to support a vertical landing.
Yep. There's some challenges with moon landing. They've added engines towards the top. You can see three ovals in some pictures. Presumably those would be Dracos but could be something else. By putting them up high that helps with not kicking up so much regolith on landing, which is a concern. The Starship is very bottom heavy. Like the boosters it's why they can retro-propulsively land on a barge. And the landing legs on Starship will be self leveling.
Currently those landing legs are under the engine skirt. There's been many iterations. At one point the fins acted as legs. Or they could do landing legs that fold out like the Falcon 9 booster.
Still it's valid concerns and no doubt will be part of the initial study.
I don't care which system NASA picks as long as it's not Blue Origin. Their plan is asinine.