All Questions
14,610
questions
0
votes
0answers
18 views
spacecraft that can be used for microgravity missions [closed]
Can you name guided and uncrewed spacecraft that can be used for microgravity missions and experiments? Nowadays it`s rather popular and useful to use uncrewed guided space vehicles for particular ...
-1
votes
0answers
29 views
Lightening As a source of energy [closed]
Is it possible to use lightning or thunder as a source of energy, with the help of dielectric breakdown and splitting. Sorry not based on space research but would appreciate the help
2
votes
3answers
140 views
Asteroid orbiting between Earth and Mars as ferry?
What if we moved a large asteroid to a highly elliptical orbit between Earth and Mars and then occupied it like we occupy the ISS?
It'd be a slow trip to Mars, but if we're in no rush, we'd get free ...
1
vote
0answers
22 views
Are spacecraft star cameras ever used as scientific instruments for research?
There are quite a lot of spacecraft that have been up there a while and a lot of them have star cameras for attitude determination and for attitude control. Space telescopes (both heavenly and Earth-...
3
votes
2answers
173 views
Are Jool's moons' orbits stable?
The fictitious Kerbol system includes
...five planets: Moho, Eve, Kerbin, Duna and Jool; and two dwarf planets: Dres and Eeloo; orbit around it. Kerbol contains 99.97 % of the mass in the Kerbol ...
29
votes
1answer
7k views
Why don't lasers last long in space?
A news article
reports that
OSIRIS-REx was equipped with two lasers for the spacecraft
to shoot off the rock and study the echo to facilitate
its landing and sampling maneuver. ...
Most lasers don't ...
1
vote
0answers
53 views
Why SN8 needed 12.5 km?
Is there a particular reason for chosing 12.5 km for the SN8 hop?
Why 5 km for example is not good enough?
1
vote
1answer
86 views
Payload capacity of Electron rocket?
I can only find the Electron capacity for LEO and SSO: 300 and 200 kg
And for Venus: 15 kg (which links to here)
But what is the capacity for GTO, Moon and Mars?
LEO = Low Earht Orbit
SSO = Sun-...
1
vote
1answer
36 views
Earth magnetic field vector in ECEF
I've this problem...
I want to express the earth magnetic field vector in ECEF reference frame. As now I've just found some models for computing these values related to the earth magnetic field:
D: ...
0
votes
1answer
87 views
How many solar system bodies have “knees” in their atmospheres?
Discussion lead to citing Why does Earth's atmospheric density have a big "knee" around 100 km? Is there a good analytical approximation? who's answer is "monatomic oxygen". ...
3
votes
1answer
98 views
Are westward launches more expensive than eastward launches?
Basic question for those who breathe rockets:
The earth's rotation imparts to the rocket a free delta V of roughly 450 m/s if you launch straight eastward.
If you launch westward instead, for a ...
-1
votes
0answers
52 views
The most advanced private space company of the present time other than SpaceX? [closed]
Nowadays, the private space company really succeeded and manufactures pretty good technology and space vehicle. What do you think is the most advanced private space company ( except SpaceX ) at the ...
2
votes
1answer
33 views
How to retrieve MSL EDL trajectory using Javascript and webgeocalc API?
I found a "javascript gateway" to NASA SPICE data, the "webgeocalc" web api:
https://wgc2.jpl.nasa.gov:8443/webgeocalc/example/perform-calculation.html
It works both online and ...
-1
votes
0answers
82 views
The fewest employees for an orbital rocket?
When these orbital rockets launched first to space, their companies had:
SpaceX - 2008 - 525 employees
Electron - 2018 - 200 employees
Virgin Orbit - 2021 - 390 employees
Astra - 2020 - 100 employees
...
4
votes
1answer
265 views
Has a rocket from a torpedo tube ever reached space?
Are submarine launches horizontal? is a general question and specifies by name two large ICBMs which are likely to need to be launched vertically.
Since the large naval submarines usually come ready-...
5
votes
2answers
2k views
Are submarine launches horizontal?
Are the rockets launched from submarines in a horizontal or vertical position?
I mean for the space launches like Volna and Shtil.
This article says
By reaching orbit, LauncherOne has become the first ...
1
vote
0answers
111 views
Why is the bottom of the SLS rocket covered with reflective silver “muffler” tape?
NASA.gov's First Artemis Rocket Stage Moved onto NASA Barge Ahead of Green Run contains a high resolution image of the rocket. The bottom end of the rocket's cylindrical shape is closed flat and ...
1
vote
1answer
60 views
How much easier is it, to explore space from a low orbit satellite, than from Earth?
Note: in this question I'm considering cost in both money and fuel terms, and looking for answers that consider both.
So we know that using chemical rockets to reach the moon, or further into space, ...
2
votes
0answers
31 views
Meteoroid impact frequency in the size range of 1 mm or larger?
I wish to know the frequency of 1 mm diameter or larger meteoroids impacting the Earth's atmosphere each day. NASA's Asteroid Fast Facts (1) says "Every day, Earth is bombarded with more that ...
24
votes
1answer
3k views
What is a “Major Component Failure” referred to in news reports about the unsuccessful Space Launch System core stage test firing?
In reporting about the unsuccessful green run of the SLS core stage, Ars Technica mentions
About 50 seconds into what was supposed to be an 8-minute test firing, the flight control center called out, ...
6
votes
1answer
211 views
Which RS-25s are on the Artemis 1 rocket?
The SLS core to be used for the Artemis 1 flight will use four RS-25 engines. These reusable engines were used on the Space Shuttle Orbiter previously.
Is there a listing of which SSMEs are planned ...
1
vote
1answer
100 views
Why doesn't NASA just again build the Altair LM or a modified Apollo LM for the Artemis project?
The Altair lunar module was part of the wonderful Constellation program cancelled in 2010; just the Orion spacecraft has been retained which is to deliver a crew into lunar orbit. The new carrier ...
1
vote
0answers
63 views
Are there any space capable countries without ITAR laws?
In the US, the draconian ITAR laws prevent an open source space program from being founded, and make it incredibly difficult to found any aerospace company in general. Are there any countries that ...
-1
votes
0answers
46 views
With a sufficiently diamagnetic material, is it possible to create thrust from a star to propel a spacecraft?
This is a showerthought after the NYtimes "tic tac" video that I've had for a while and am looking for a specific answer. Assuming a perfectly diamagnetic material exists, could an object ...
2
votes
0answers
49 views
What happens to ablative nozzles after a test fire?
For example RS-68 engine
If you make a test fire of an ablative nozzle engine then the fire will consume the coating of that nozzle.
That means you have to replace the coating or the entire nozzle.
...
2
votes
1answer
56 views
Will there be any additional benefits of reusability for the space tug?
We are now seeing certain advantages of the reusable use of different rocket stages. Decrease in price (perhaps not so much yet), increase in launch reliability, etc.
Are there any other benefits of ...
0
votes
2answers
177 views
Why is the Orion spacecraft so big?
The Orion spacecraft which is to be used for the Artemis missions will be rated for 6 astronauts. Why so many? Given the "political" assignment is to put "a woman and another man to the ...
1
vote
2answers
82 views
Why does it cost more to get to L4/5 than C3=0?
I was looking at Delta-V budgets and noticed that it costs 4.1 km/s to get from LEO to L4/5, but just 3.2 km/s for LEO to geocentric C3 = 0 (escape velocity).
I find that counter-intuitive. Why does ...
13
votes
4answers
4k views
Why is it so hard to build crewed rockets/spacecraft able to reach escape velocity?
Why are we still not going farther than to Low Earth Orbit? Orbital velocity is about 4.8 mi/s (7.7 km/s) and escape velocity is about 7 mi/s (11.2 km/s), about 45% faster. Why is it so hard to reach ...
0
votes
0answers
30 views
Moon Mission - Mars Mission
They can stay on the moon only around for 3 days because of the fuel but they need around 6 months to reach Mars. Now they are working on the Propellant depot project to be able to reach the moon and ...
0
votes
0answers
40 views
How long to flip over stage 1 of Falcon 9?
Curious how fast stage 1 flips over.
180 degrees is a lot of turning.
At a rate of 5 deg/s, it would take 36 seconds to flip. This seems very long for the maneuver.
A more modest duration of 10 s ...
0
votes
0answers
33 views
Does apsidal precession rate have any dependence on the argument of periapsis? Perhaps higher order?
Writing this comment got me thinking, which invariably leads to confusion in my case.
@DavidHammen's answer to show that for Juno's near 90° polar orbit the major precession is apsidal; periapsis is ...
0
votes
1answer
56 views
Falcon 9 altitude and speed during reentry burn?
After MECO, stage 1 of Falcon 9 does up to three engine burns: a boostback burn followed by a reentry burn followed by a final landing burn.
I'm interested here in the reentry burn. How high and how ...
2
votes
2answers
74 views
How big is an orbit of “X by Y miles”?
While reading the NASA overview of Apollo 11, says:
Apollo 11 launched from Cape Kennedy on July 16, 1969, carrying Commander Neil Armstrong, Command Module Pilot Michael Collins and Lunar Module ...
4
votes
2answers
1k views
Rocket fuel cost to launch 1 kg to orbit
I have 2 questions about the cost of liquid rocket fuel to launch (anything) to LEO orbit. Let's assume we use fuels used in commercial spaceflight today (probably LOX+LH2 or LOX+RP-1 etc.).
What is ...
3
votes
0answers
35 views
How to get MSL coordinates during EDL from SPICE kernel?
Upon trying to extract MSL position above surface by decoding a SPICE kernel, I am gettin this error:
At epoch 3.9750216818313E+08 TDB (2012 AUG 06 05:16:08.183 TDB), there
is insufficient ...
4
votes
0answers
84 views
What are the implications of North Korean black and white patterns on missiles?
Black and white patterns on rockets were originally intended as roll patterns. They helped as a visual back-up for acceleration sensors measuring the roll, as discussed in this previous question What ...
2
votes
0answers
46 views
How much lower is max q if launching from high altitude (i.e. mountain top)?
I looked at very simple max q formula: q=1/2 ρv^2 (https://en.wikipedia.org/wiki/Max_q). As air density is lower with altitude, the max q should be lower as well, and also should occur at higher ...
-1
votes
0answers
21 views
Spacecrew member eligibility in future manned NASA space missions [duplicate]
What are the eligibility requirements to be part of future Spacecrew mission NASA programs?
Age, Nationality, Medical Fitness, Educational qualifications, Work experience etc
2
votes
0answers
94 views
Can ten (or more) rockets be used together to launch one massive object?
With computer flight controls where they are today, what would stop us from building a relatively large space station on earth, but then using 10 or 20 or even 100 falcon heavy or Starship or SLS ...
0
votes
0answers
18 views
Calculating Pressure Inside Combustion Chamber
I am trying to calculate the pressure inside a combustion chamber of a rocket candy. My "engine" is made out of PVC with an internal diameter of 1/2 in. Are there ways for me to calculate ...
4
votes
1answer
76 views
Details about Rolls-Royce / UK Space Agency's nuclear propulsion?
The UK Space Agency, on 2021 Jan 12, announced a research contract with Rolls-Royce for nuclear propulsion of spacecraft, based on R-R's experience with nuclear power for submarines. The press ...
1
vote
0answers
32 views
Falcon 9 Angle of attack on return flight?
Do they control for angle of attack on the return flight of stage 1 of Falcon 9?
Once it reenters thick atmosphere, aerodynamic stresses would be a concern as during launch, maybe more so because you ...
0
votes
0answers
53 views
Starlight: are the rays that we see here on earth parallel? [migrated]
Are the rays of light emitted from stars that are perceived by an eye here on earth parallel?
Do they travel in a straight line from the star to the eye, never crossing, and equidistant?
Do they ...
2
votes
2answers
190 views
Is Delta V depending on the Launch Vehicle mass and the Payload Mass?
I have read in many references that Delta V is fixed or constant for example ( Delta V to LEO = 10km/s). They did not mention the payload mass or the Propellant mass, and also they did not mention ...
-1
votes
1answer
110 views
New Shepard payload capacity to orbit?
If the current Blue Origin New Shepard were modified as little as possible to work as the first stage of a two-stage rocket, what would be its maximal LEO payload?
To put it in other words: out of all ...
0
votes
3answers
90 views
Orbital launches
In the 1950s, many US rockets were capable of reaching the lower limit of LEO altitude. Despite this, no one thought of making the launch vehicle / its payload orbit around earth, even for one ...
0
votes
1answer
47 views
Estimating time to engine cutoff?
I'd like to calculate the approximate time left to my stage-1 velocity target.
A simple way to do this would be to divide my Delta V by my acceleration. Trouble is... my acceleration changes ...
2
votes
2answers
471 views
Pressure levels inside rocket liquid oxygen tanks?
What is the pressure levels inside rocket liquid oxygen tanks, at launch time?
The question is for the minimum and maximum (known) levels of pressure inside such tanks.
I am asking for any rocket ...
1
vote
0answers
55 views
Any large scale rocket static fires, like SpaceX's 3 in one day?
SpaceX on Jan 13, 2021 did three static fires in one day.
Elon Musk tweeted:
All three static fires completed & no RUDs!
And that was in response to this tweet of his own:
Today at SpaceX is ...