Nefrums
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KSP2 Release Notes
Posts posted by Nefrums
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On 8/26/2020 at 5:08 AM, cubinator said:
Water is a rather finite resource on the Moon...mining it for rocket fuel might be unsustainable in the long run.
Well according to wikipedia:
moon is 0.1% water. moon mass is in the order of 10^22 kg, starship has in the order of 10^6 kg fuel.
so we can only fuel it 10^12 times with water from the moon.
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Was just thinking if a 18m next gen starship could have artificial gravity?
According to this chart is could be possible:
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HYPE!!!
When does the beta start and where do I sign up??
I need to go stream KSP now!
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3 hours ago, RCgothic said:
Ionising radiation only comes in three types.
Alpha, beta, gamma, proton and neutron, are five out of those three right?
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1 hour ago, Xd the great said:
They get thrown away, i believe...
Or else the reentry EM radiation will overcharge the dragon 2
The solar panels are on the trunk.
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If one of the second stage engines got damaged during irst stage separation, that could cause the tilting and the shutdown of remaining second stage engines.
I assume that soyuz does not have engine out capability.
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17 minutes ago, kerbiloid said:
It said that the second stage engine did a emergency shutdown. So the rocket must have been in free fall during the separation.
Thou I assume that a fully fulled center core that is on the same ballistic tragectory as the capsule can pose some danger to the crew.
But the parachutes should make the capsule land some distance from the inferno where the booster lands.
EDIT: With fully fulled center core I mean with whatever fuel is left after side booster separation...
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The second stage is the center booster right?
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I always thought that black holes could be viewed as a big nucleon, in the same way as a netron star could be described as a big atom.
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Well you would have little more than a billion km3 of water to get rid off.
Anyone thirsty?
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It looks like the "wings" can move. If they can tilt a lot it could, together with the top fin, make ship fairly stable reentering belly first.
Could it be that the entire engine segment is movable? So that they can slide it deeper into the body? That would move CoM, something that would simplify the flipping maneuver. and it could also make the skirt around the engine act as a vacuum nozzle (not sure that could work)
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5 hours ago, Xd the great said:
Lets test that in ksp.
Doing that in a reasonable dV efficient way would mean 100+ years travel time from Uranus to Pluto.
We are talking about planets with orbital periods of 84 and 250 years here...
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11 minutes ago, Wjolcz said:
It would be pretty cool if they could produce their own fuel on Earth. But since the BFR/BFS will be fully reusable even if they buy fuel and ship it they would probably charge less than for a F9 launch.
BTW, does anyone know how much money will they be charging per launch? The fuel can't cost more than a brand new F9, right?
Fuel cost is not significant. It is less than 1% of launch cost
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probably easier to launch a bunch of tanks with Hypergolic fuel into mars orbit and use that for landing/return Even a falcon heavy could put close to 10 tons of fuel in mars orbit.
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3 hours ago, cubinator said:
Most of the night/early morning launches I can think of have been interplanetary satellites.
Assuming that interplanetary mission want to get into the earth sun orbital plane. It would make sense to launch at night during the winter and in the middle of the day in the summer.
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The problem is finding 150t of payload that wants to be in the same orbit.
That could be solved by building a small satellite kicker stage with a few km/s dV. And strap one of those to each satellite.
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On 3/30/2018 at 3:18 PM, sevenperforce said:
In practice, there's a total moratorium of in-atmosphere tests on any NTRs, because in theory some of the liquid hydrogen will mutate by neutron capture and turn radioactive.
Even though there's NO actual risk of harm. From that part, at least.
Mutate? Neutron capture turns hydrogen into deuterium, that is stable not radioactive.
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Like all other plans ever in history. It will be changed.
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2 hours ago, Rakaydos said:
Is the atmospere at 200 km the same proportions as lower, or is there gravity-separation?
If it's the same, you're collecting 78% nitrogen and 21% oxygen. The oxygen is useful, but the nitrogen tkes a lot of processing to become usful nitrogen compounds, and can probably be tossed. The question is whether your PFA can split different types of gasses in orbit, or whether it justcompresses them and lets another vessel handle separation.
the proportions is different:
"The lighter constituents atomic oxygen (O), helium (He), and hydrogen (H) successively dominate above about 200 km altitude"
https://en.wikipedia.org/wiki/Thermosphere
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I still doubt your sources on this. @Green Baron
Where have you gotten this information from?
According to https://data.worldbank.org/indicator/IT.CEL.SETS.P2 the number of cell phones per person is not that different between most countries any more.
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2 hours ago, Green Baron said:
Musk's example of Africa is beyond reality (as usual i am tempted to say), few people away from the population centers actually have money and even fewer for something like an internet connection and the necessary power supply.
I think you need to update you information sources on that, It looks like they are 20 years out off date..
I think Musk knows hat he is doing. Wireless telecom is a trillion $ yearly market. He don't need to get that much of a market share to make up for a few hundreds billions in investment costs.
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5 hours ago, magnemoe said:
SpaceX system will not work against phones, you would need an receiver more like an large wireless router.
it will however work well against moving targets like cars or even planes.
Even iridium phones are pretty bulky, for something like modern smart phones you probably need BFR and even then probably an way to print the antenna in orbit.
Now the interesting part is that bandwidth is pretty shared so who more remote you are who higher bandwidth as few other uses it.
Opposite of standard broadbandIt will not have one big antenna, more like 256 antennas in a grid in order to get good beam forming.
But the anatemas will still need to be quite big and transmit on pretty high power to get good throughput. The satellites will have to have big solar panel arrays and batteries to last the hour it takes to pass the night side.
5 hours ago, sh1pman said:Not to mention the signal delay. I don’t think you’ll be able to play online games with it.
Bouncing a signal off LEO would take about 13ms
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19 minutes ago, sevenperforce said:
Thank you.
The core did a boostback burn, but we don't know how much of a boostback burn it did (though very careful analysis of the net webcast might suss it out). Did the boostback bring it down to single-stick GTO velocities? If not, then perhaps hitting the atmosphere at far higher velocities than normal caused ignition problems, requiring a longer shot of TEA-TEB and depleting the supply.
Something to fix, yes. But that's the point of a test flight.
I wonder if the core had enough margin to do a 1-0 landing burn like CRS-8. I doubt it; if they had the margin, they would have used it.
They have three landing burn configurations: 1-0, 1-3-1-0, and 1-3-0. In 1-0, they perform the entire landing burn with the center engine and shut it down at zero-zero (that's zero velocity, zero altitude). In 1-3-1-0, which has been the approach for almost all ASDS landings, they start the burn with one engine, ignite two side engines to kill almost all the velocity, and then shut those two down and use the center engine with fine throttle control for the landing.
1-3-0, which they tested on Govsat, burns all three engines all the way to zero-zero.
This was most likely a 1-3-1-0, but if one of the two side engines failed to ignite, the center engine would continue to burn merrily away as it plunged into the ocean.
Ok, that makes sense.
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3 minutes ago, RizzoTheRat said:
Presumably the core went higher than the usual Falcon 9 stages so faster on the way down and needing more thrust?
Thrust is not an issue, one engine is capable of slowing down the rocket. But as all KSP players know, a higher TWR means a more efficient landing, with a shorter burn that saves dV.
I doubt that was actually needed on this launch. They could most likely have landed the core with one engine. More likely is that they wanted to test yet another new thing on this test flight.
I made it to Duna and back
in Mission Reports
Posted
This was supposed to be easy. It was not.
Some things that went wrong:
Full vidio is available here: https://www.twitch.tv/videos/1748896188