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DrZ214's user avatar
DrZ214's user avatar
DrZ214
  • Member for 10 years
  • Last seen more than a month ago
32 votes
2 answers
3k views

How can a sounding rocket accurately take the temperature of the atmosphere while flying through it at high speed?

27 votes
4 answers
8k views

Why do deep space probes have to be sterilized?

25 votes
2 answers
3k views

How does Venus' thick atmosphere survive against the solar wind?

19 votes
1 answer
9k views

What is so hard about making a throttleable large rocket engine?

18 votes
2 answers
2k views

How big a weight problem is ice sticking to a rocket?

17 votes
4 answers
4k views

For a typical Shuttle mission, how much solid fuel is leftover at SRB separation?

15 votes
4 answers
6k views

Is LMP-103S truly a viable replacement for Hydrazine?

14 votes
3 answers
3k views

Did we know the gas planets were truly gaseous before Pioneer 10?

14 votes
1 answer
4k views

What solid fuel was used in the Katyushas rocket artillery of WW2?

12 votes
2 answers
4k views

Why does the Soyuz spacecraft's parachute have so many lines?

12 votes
4 answers
11k views

Why do pressure-fed systems have to be pressurized with helium or nitrogen?

12 votes
1 answer
698 views

Was there ever a non-sterilized probe sent to a celestial body?

11 votes
1 answer
1k views

How were the Space Shuttle missions named?

10 votes
3 answers
1k views

A cryo tank within another cryo tank...is it a sound engineering concept?

10 votes
1 answer
1k views

How is blow-back prevented in monopropellant chemical rockets?

10 votes
2 answers
649 views

Was Hipparcos Satellite really necessary? Can't Hubble do everything that Hipparcos did?

9 votes
2 answers
3k views

What is the correct thrust curve for a solid rocket with a simple circular hole, and why?

9 votes
2 answers
2k views

How are spacecraft engineered to prevent overheating?

9 votes
2 answers
543 views

In Apollo hardware, why were sump tanks needed?

8 votes
2 answers
4k views

What are the energy-to-mass ratios of some fuels/oxidizers, when including the oxidizer?

8 votes
1 answer
841 views

Why is space junk so persistent in LEO?

8 votes
3 answers
2k views

What were the highest quality photos and knowledge of Uranus and Neptune before Voyager?

7 votes
1 answer
900 views

How much power does the Voyager radio dish draw?

7 votes
2 answers
2k views

Which is overall more expensive to operate for a final rocket stage? LH2/LOX or hypergolics like UDMH/N2O4?

7 votes
1 answer
2k views

What exactly does it mean to human-rate a rocket? As opposed to the escape system?

7 votes
1 answer
942 views

What was the first large rocket to use APCP solid fuel?

6 votes
3 answers
3k views

Are cold gas thrusters viable for model rockets?

6 votes
2 answers
6k views

What does "self-pressurizing" mean in regards to propellant tanks?

5 votes
1 answer
10k views

What is the flyaway cost of a Soyuz and Proton Rocket?

5 votes
3 answers
1k views

How does a radiator work fast enough on a space craft?