All Questions

3
votes
0answers
38 views

What main engine used in a series of environmental satellites has failed more than once (according to the GAO)?

A GAO report on NASA's ongoing projects can be found here. On page 70 while discussing the Lucy mission, it says the ... main engine was the same model used on a series of environmental ...
2
votes
0answers
32 views
5
votes
2answers
153 views

How soon after “The Eagle” landed did they first attempt to bounce a laser off the Moon? When did it first succeed?

The question When did Houston figure out where the Eagle had landed? says (in part): During Apollo 11's stay on the surface, Michael Collins was given seven different locations to look for the ...
2
votes
3answers
152 views

Do Curiosity's reported measurements of Mars' surface gravity (~3.717 m/s^2) include centrifugal effects?

In this answer I discuss the first results in the 47th Lunar and Planetary Science Conference (2016) conference paper First Gravity Traverse on the Martian Surface from the Curiosity Rover and a more ...
5
votes
0answers
85 views

Has Curiosity started driving backwards yet?

I'm curious if curiosity has started to drive backwards, at least occasionally, as part of an effort to reduce the rate of damage to the wheels. This has come up after writing this answer to the ...
11
votes
1answer
210 views

When did Houston figure out where the Eagle had landed?

Between starting the descent burn three seconds late, and having to avoid landing in a boulder field, the Apollo 11 descent module almost completely missed the target landing ellipse. During Apollo ...
1
vote
0answers
43 views

Longer lasting missions [closed]

I realize the tremendous advances in the length of missions the last 20 years but I have a lay question so please don't beat me up. If an asteroid such as Oumuamua, billions of years old has the ...
2
votes
1answer
80 views

Does JPL's Horizons have better MU69 state vectors for the New Horizons flyby somewhere?

Today I downloaded the state vectors for New Horizons and MU69 Ultima Thule and subtracted their positions. The two new get closer than about 596,000 kilometers. The New Horizions output header says: ...
2
votes
1answer
56 views

How does the chamber pressure affect the performance of a Rocket Engine?

I am under the assumption that higher chamber pressure results in increase in exhaust velocity. Is this true?
3
votes
1answer
99 views

What propulsion will Lucy use for its deep space maneuvers?

The Lucy trajectory described in several excellent answers to this question involves a number of fairly large (in delta-V terms) deep space maneuvers, totalling (same source) about 1.5 km/s over ...
17
votes
5answers
4k views

Will there be back-side photos of Ultima Thule?

I understand the reason we're only getting data slowly from New Horizons, but I was wondering ... did the probe flip around to get hi-resolution photos of the back side of Ultima Thule as it passed? ...
2
votes
0answers
41 views

How to measure the effect of the propellants to the thrust of the ion engines in a diy experiment? [duplicate]

I have a science project about how different propellants affect the thrust of an Ion engine. So I have 2 questions: How can I measure the thrust of a diy ion engine? (technique or tool that I need to ...
3
votes
0answers
103 views

Is it possible to see a spacecraft orbiting the moon with a pair of binoculars? [migrated]

On this clear early morning over London, I was studying the moon with a pair of binoculars and noticed a tiny dot of light that appeared to trace a slow orbit around the moon. I reckon it moved ...
7
votes
1answer
95 views

Would radio / wifi and other communications work on Jupiter's moons?

I've read that Jupiter emits a lot of EM radiation, and can also be heard on ham radio. If you were much closer would it drown out radio and other forms of communication, or is it confined to specific ...
7
votes
4answers
256 views

How to measure thrust of experimental ion engine

I have a science project about how different propellants affect the thrust of an Ion engine so I have 2 questions: 1 How can I measure the thrust of a diy ion engine ( technique or tool that I need ...
6
votes
1answer
553 views

What is “light bar testing”?

A photo of the Parker Solar Probe was captioned as follows: In the Astrotech processing facility in Titusville, Florida, near NASA's Kennedy Space Center, on Tuesday, June 5, 2018, technicians and ...
1
vote
1answer
65 views

Heat Shielding Material for Reusable Craft

I'm a bit new to all this and have a quick question about heat shielding. My research tells me that for reusable craft (i.e. Space Shuttles) they used to use a plastic-based shields that would burn ...
0
votes
0answers
64 views

Which Cubesat Cameras Actually Worked in Orbit before 2019?

Short question: Which Cubesat Cameras Actually Worked in Orbit before the year 2019? Context and explanation: The very few missions which published at least one image I've found: Planet Labs ...
4
votes
0answers
51 views

How do international students attend the SA Cup sounding rocket competition?

How do the international students carry the rocket along with propellants to this competition, if Airport Authority does not allow flammable substances?
2
votes
0answers
58 views

How can I calculate the density of Mars' atmosphere during dust storms?

I have been searching to try to estimate the air density of the atmosphere on Mars during a dust storm. I am trying to use this dynamic pressure equation to calculate the pressure on a theoretical ...
6
votes
1answer
282 views

The aerodynamic stability of the truncated cone shape

Can someone explicate the stability of the truncated cone shape of the reentry vehicle of a spaceship when moving in the atmosphere with its bottom facing forward? It seems counterintuitive that it ...
5
votes
0answers
68 views

How are the payload limits of robot arms on the space station determined?

I have just been wondering how the payload limits for the arms on the ISS were determined. Any back of the napkin calculations to explain these? In that vein, I could not find any information on the ...
2
votes
1answer
81 views

How is the exit velocity of the flow in a sounding rocket nozzle?

How is the exit velocity of the flow in a sounding rocket nozzle? Is it subsonic or supersonic? Is a de Laval nozzle required for sounding rockets? Bonus Question: What about Model Rockets?
3
votes
1answer
99 views

Could you use magnets to orient in space?

If I had a tiny satellite with a magnet orbiting Earth (or another body with a magnetic field), could I use this magnet to adjust my attitude? I'm thinking it could be used in sort of the same way as ...
4
votes
1answer
128 views

How might SpinLaunch actually spin something fast enough to launch it into orbit?

Ars Technica's Edition 1.34 of the Rocket Report! says: SpinLaunch signs deal with Spaceport America. Spaceport America has announced that SpinLaunch has signed a lease to conduct tests at the ...
4
votes
3answers
296 views

Two 1000 kg gold spheres orbit their CM in near-contact, great way to measure G or limited by spaceflight issues?

The hypothetical, non-existent crowdfunding site go-launch-me is so confident, they are offering a two-for-one special. For a limited time, if your project is funded they will foot the bill for a 2nd ...
5
votes
0answers
54 views

What are the space-based optical satellite sensors?

I was looking at a products page for Numerica Corp, and under their product MFAST it said (emphasis mine): Tracks objects in all regimes of space (e.g., LEO, MEO, HEO, GEO) using radar, ground-...
2
votes
1answer
76 views

Satellite Telemetry on the Internet

Are there any web sites that show real time telemetry such as temps, bus voltages etc? Looking for one to follow.
3
votes
1answer
52 views

Using DART to measure G

NASA plans to launch a mission called DART to kinetically impact an asteroid, primarily for the defense of Earth. One thing that I've been thinking about is the same mission could be used potentially ...
3
votes
1answer
39 views

How to obtain the initial positions and velocities of an inclined orbit?

I have (x,y,z) initial positions and (vx,vy,vz) initial velocities in a coplanar orbit with respect to the reference frame. If I change the inclination of this orbit with the angle i, how I can ...
16
votes
8answers
9k views

Why didn't Voyager 1 and Voyager 2 crash on into Jupiter or Uranus when they approached near to these massive planets?

I was reading about gravity assist and I read that both the Voyagers used gravitational force of these planets to speed up. But I wanted to know why weren't they completely attracted by their ...
2
votes
0answers
55 views

Payload fairing separation- Event based or time based?

Refer the answer for this question How strong and "hot" is the wind on the payload after the fairing is deployed at ~110km? It is clear that the fairings are separated when the free ...
2
votes
1answer
124 views

Is it possible to capture geostationary satellites with DSLR?

DSLR is to be mounted on a tripod and pointed at sky with a zoom lens. Would a sufficiently long duration of exposure reveal these non-moving satellites as bright "stars" amongst the streaks caused ...
1
vote
0answers
44 views

New Terran 1 rocket - launch costs for Cubesat

I was reading about the Terran 1 rocket and the fact that the founding company managed to secure the launch site at Cape Canaveral. Pretty amazing story on its own but then I looked at prices and they ...
1
vote
1answer
385 views

How to drink water on Mars?

There are craters filled with water on Mars as shown below. If fresh water is found, how would astronauts drink the water? Can the Apollo a spacesuit food/drink port be used to equalize the pressure ...
3
votes
1answer
104 views

How to get water inside a space suit?

How is water transferred from outside the suit to inside the suit?
1
vote
0answers
26 views

Spin of the sounding rocket [duplicate]

I saw a video of a sounding rocket, where the rocket`s outer body was spinning very fast. Why does that happen?
1
vote
1answer
143 views

Is no one except Elon Musk using steel to build rockets? [duplicate]

Recently Elon Musk tweeted this picture of the SpaceX prototype Starship, which they will use for VTOL. He said that steel is cheaper compared to carbon fiber and has high melting point etc, which ...
5
votes
0answers
69 views

How similar to a crewed flight will SpaceX Demo Mission 1 be?

With the upcoming premiere of the Dragon 2 in SpaceX's DM1 launch, I was wondering how similar it will be to a mission with actual astronauts. What I mean by this is things like: Will the launch ...
3
votes
2answers
83 views

Do air augmented rocket give increased thrust over simple rockets from the very starting of the engine?

Augmented rockets increase thrust (about twice) by mixing the exhaust of a rocket with ambient air in order to accelerate a greater mass of gas at a lower speed. Is the effectivness of this system ...
2
votes
0answers
159 views

Use of thrusters for Collision Avoidance Maneuver

I'm building an orbit propagator that gives the position of two satellites at time T. The position are expressed in ECI and after that are being transformed in LVLH frame (as mentioned ECI to LVLH ...
1
vote
1answer
75 views

Are there any photographs of the frozen waste water after a urine dump in space?

Astronaut Mike Massimino talks about watching the urine freeze outside of the spacecraft. He said they would all watch, it was something beautiful to see. Are there any photographs of this, or has ...
21
votes
6answers
8k views

Was water ever taken outside a spacecraft?

Has an astronaut (or cosmonaut) taken water out of a spacecraft to see if it boils or freezes?
3
votes
0answers
73 views

Crew Dragon SuperDraco Engine Covers

(Source: Nasa Spaceflight article) While looking at the new images of the upcoming crew dragon launch I noticed a distinct lack of holes in the part of the dragon the Engines are supposed to be in. ...
1
vote
0answers
53 views

Why does the PSLV first stage's exhaust plume turn to bluish at high altitude?

After few seconds, post liftoff(anywhere between 60s and 90s), the exhaust plume of PSLV turns into a bluish colour. This is quite evident in night launches than day launches(obviously because the ...
6
votes
0answers
180 views

What is “OBJECT BS”?

I checked 2018-099 in Celestrak's satcat again for the question Where can I find the TLE of ExseedSat 1, India's first ever private LEO satellite? and noticed that ...
2
votes
0answers
38 views

Need help with selecting research papers for Cycler Trajectories

I have been reading small articles on Cycler trajectories and have found it to be quite interesting. So, I was wanting to do some research work in this area and I need help in acquiring research ...
4
votes
1answer
115 views

What methods are proposed for storing cryogenic fuels (esp. hydrogen) in space for months or years?

Current Launch vehicles and upper stages must only keep their fuels for minutes or hours, so they are only insulated to keep boiloff to a few % per day - I've seen 21% per day quoted for Centaur on ...
19
votes
1answer
187 views

What was NASA's Tire Assault Vehicle?

Why did NASA build a vehicle specifically designed to attack aircraft tires?
4
votes
1answer
140 views

Solar eclipse question [closed]

In a solar eclipse, are we seeing it as the eclipse takes place in real time, or do we see it 8 minutes after it happens because that’s how long the light takes to travel from the sun?

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