All Questions

Filter by
Sorted by
Tagged with
60 votes
4 answers
17k views

Would terraforming Mars be possible?

Mars is a planet commonly brought up when talking about terraforming. Even if we were to manage to get past all economic barriers, and somehow form a thick atmosphere, would the lack of a magnetic ...
Chris Loonam's user avatar
  • 1,095
60 votes
4 answers
7k views

What resources could be gained from asteroid mining that would be worth the effort?

Obviously asteroids are abundant in many of the raw materials we use today, but considering the (presumably) large expense involved in mining from asteroids it may not be worthwhile to mine some ...
called2voyage's user avatar
  • 23.7k
11 votes
3 answers
1k views

Ultra-lightweight material for structural components - aluminium foam?

This is (again) something from the back of my head, that I am looking for right now. I think that in 2008, I saw a presentation on foamed / expanded aluminium for structural components (1). The ...
s-m-e's user avatar
  • 6,561
15 votes
3 answers
2k views

Cubesats in lunar orbit and beyond - how does communication work?

Somewhere I read that there are serious plans to send a cubesat into lunar orbit. A few years ago, the ISS was also offering a launch opportunity for such a mission. I guess that it was actually ...
s-m-e's user avatar
  • 6,561
19 votes
2 answers
4k views

How far from the Sun can solar power be used as a reliable energy source?

Space probes headed for the far reaches of our Solar System rely on radioisotope thermoelectric generators for power (Cassini–Huygens, Voyager 1, Voyager 2). Presumably this is because solar power ...
JohnB's user avatar
  • 2,162
18 votes
2 answers
3k views

Are there any successors to Voyagers underway currently?

We've seen quite a few probes examining the Solar System in the recent years, but beyond Voyager delivering new measurements every couple months now, I haven't heard about any of the probes underway ...
SF.'s user avatar
  • 54.9k
24 votes
1 answer
2k views

How are flight plans calculated?

When a project like Rosetta is being developed, how are flight plans calculated? Do planners simply input the desired target into a program or a flight computer which spits out the optimum flight path ...
coleopterist's user avatar
  • 6,043
13 votes
3 answers
3k views

Does Mars contain materials that could be used to build a space colony?

If a manned mission to mars was made with the hope of colonization, we would probably need to make many of our structures there out of materials found there - they would probably be simply too heavy ...
user avatar
12 votes
3 answers
460 views

What is the range of strength for asteroidal materials?

Observed rotation rates of small asteroids point to a limit on the material strength of these bodies. This limit is not very high But that's only part of the picture, because an upper limit on ...
AlanSE's user avatar
  • 16.2k
33 votes
3 answers
3k views

Is it possible to get pregnant through natural means in space?

The Russians did some early testing with rats (Packing for Mars: The Curious Science of Life in the Void, By Mary Roach pg 245) and natural means did not result in pregnancy. Later testing shipped ...
James Jenkins's user avatar
15 votes
4 answers
12k views

Energy consumption for travelling to the Moon vs. to Mars

I just finished reading Clarke's "Prelude to Space". In chapter XXVII the character Taine gives a talk where he states It sounds paradoxical, but it's easier to make the forty-million-mile journey ...
herzbube's user avatar
  • 253
10 votes
6 answers
869 views

Alternative data transfer channels for inter-stellar probes?

The problem how it is possible to receive data from Voyager I at all is dealt in this question: https://physics.stackexchange.com/questions/13227/how-earth-communicates-with-voyager-i However, there ...
user avatar
9 votes
3 answers
390 views

Alternative energy sources for inter-stellar probes?

Are there any alternative energy sources to power inter-stellar probes such as Voyager I and II developed or in development by any space agency? Plutonium (238-Pu) has a half-life of about 87,7 years,...
user avatar
9 votes
1 answer
391 views

How to design a spacecraft to cope with redshift?

Redshift occurs whenever an observer moves away from (shifted to the red) or approaches (shifted to the blue; blueshift) an object that emits radiation and the other way around. Traveling towards ...
bastik's user avatar
  • 1,237
22 votes
1 answer
5k views

On-board computer / data handling system of Rosetta - details?

I seek detailed information on the computer and/or data handling system of Rosetta. Who manufactured it? What type(s) of CPU is used? What kind of architecture does it belong to and at what ...
s-m-e's user avatar
  • 6,561
17 votes
1 answer
286 views

Why did the HiRISE camera team choose the wavelengths they did?

The HiRISE camera on the Mars Reconnaissance Orbiter has 3 color sensors, red (440-850nm), blue-green (400-600nm), and near-infrared (800-1000nm). Why these particular channels? Why not standard ...
PearsonArtPhoto's user avatar
  • 121k
13 votes
1 answer
509 views

What plans are in place or being considered for management of the far side of the moon?

Popular potential uses of the far side of the moon include radio telescopes & mining for Helium-3 (good potential for use as a fuel in fusion reactors). These two activities are not necessarily ...
James Jenkins's user avatar
11 votes
3 answers
356 views

Is the rigorous disinfection process prior to launch necessary?

Before a rover or other exploration vehicle is launched, it undergoes rigorous cleaning and disinfection, such as a bath in UV rays to kill off bacteria. The official reasoning on this seems to be ...
user avatar
14 votes
2 answers
2k views

Which precious metals have been detected via samples taken from Earth's moon or Mars?

Have any of the rock samples (or meteors from Earth's moon or from Mars) provided a measurable amount of gold, silver, platinum or any other precious metals?
Major Stackings's user avatar
13 votes
1 answer
880 views

Has any country stated its official position on how it would respond to a discovery of intelligent extra terrestrial life?

There are currently many programs that are attempting to find intelligent extraterrestrial life. Putting aside the fact that I believe that the chances of this are slim to none, I'm interested in ...
user avatar
19 votes
2 answers
2k views

Do any spacecraft use GNSS for attitude determination?

In principle, by placing a GNSS-receiver on all extremities of a spacecraft (or aircraft, for that matter), one can determine the orientation of the satellite. Google lists some studies, but have ...
gerrit's user avatar
  • 11.5k
22 votes
2 answers
1k views

How far up have satellites used a GNSS for positioning, and how does the precision degrade with altitude?

GNSS satellites (at least GPS ones) are in Medium Earth Orbit (MEO). LEO satellites can use GNSS for positioning. Is this still possible for satellites in elliptical, such as Molniya, orbits? For ...
gerrit's user avatar
  • 11.5k
11 votes
1 answer
394 views

In LEO, what is the precision of GNSS-based position compared to traditional methods?

GNSS satellites (at least the GPS ones) are in MEO, so LEO spacecraft can use GNSS for their positioning. I've read that it's quite low-cost compared to the alternatives. How does the precision of ...
gerrit's user avatar
  • 11.5k
12 votes
2 answers
2k views

How do space missions preserve their batteries for so long?

If I have a set of rechargeable batteries, I count myself lucky if I can get them to last for more than 2 years. Yet there are many spacecraft out there, which use their batteries much more regularly ...
PearsonArtPhoto's user avatar
  • 121k
16 votes
4 answers
3k views

Are there plans for another mission to Titan?

I've always liked the idea of exploring the moon Titan, most likely because of the atmosphere, pressure, and the fact that it has stable bodies of liquids at the surface. Although it's very cold, ...
Chris Loonam's user avatar
  • 1,095
8 votes
1 answer
138 views

Is there research on optimal control/command strategy/hierachy?

On manned-missions which take its participants further and further into space it will be quite difficult to have a control center on Earth as it takes longer an longer to communicate. It takes the ...
bastik's user avatar
  • 1,237
14 votes
2 answers
2k views

Does the Dawn spacecraft have the potential for an extended mission?

The Dawn spacecraft is scheduled to arrive in initial orbit around Ceres in February 2015 with a final planned orbital change in December to reduce its orbit to a 700km altitude. At present I can't ...
Dan Is Fiddling By Firelight's user avatar
11 votes
3 answers
2k views

Physics and math behind flight through solar system [closed]

I wrote a program that simulates a solar system. I was able to calculate the locations for every planet on its elliptical route for any given time. In a second project, I managed to simulate newtonian ...
joe's user avatar
  • 373
15 votes
4 answers
5k views

Could black holes be used for swing-by?

Due to gravity and movement an object can be accelerated (positive/negative) and slingshot into another direction. This has been used various times, but as far as I know with orbital objects like a ...
bastik's user avatar
  • 1,237
11 votes
2 answers
618 views

Is there any research or recommendations for a diet in microgravity?

The Dietary Reference Intake (aka RDA) is formulated for humans operating at one Earth gravity. Is there a similar reference or any research supporting specific recommendations for a human in ...
James Jenkins's user avatar
12 votes
2 answers
1k views

What is the first non-solar-system object Voyager 1 will run into?

I know that the farthest man-made object from Earth is Voyager 1, and was wondering if and when it will ever come relatively close to another star system, or some other object located outside the ...
Chris Loonam's user avatar
  • 1,095
5 votes
3 answers
2k views

Could a black hole be used as portable gravity device? [closed]

I don't use the term artificial gravity because, the gravity from a black hole is real. If you have harnessed and are able to control a black hole would you be able to use it as portable gravity ...
James Jenkins's user avatar
32 votes
1 answer
2k views

How long will communication with the Voyager probes continue?

Voyager 1 and 2 are the most distant man made objects. How long will we be able to still communicate with them? What will be the first thing that prevents communication? RTG exhaustion? Signal ...
Erik's user avatar
  • 10.1k
50 votes
5 answers
6k views

How possible are 'space jumps'?

Have you seen the first of the two new Star Trek movies? Kirk (Chris Pine), Sulu (John Cho) and a red shirt perform something really awesome in this film: They jump from space down to a planet, ...
s-m-e's user avatar
  • 6,561
12 votes
1 answer
1k views

What are the differences between the Falcon 9 (1.0) and the Falcon 9 (1.1 or F9R)?

With the change at the 6th launch from the original Falcon 9 design for the first five launches, to the new design, either called Falcon 9 v1.1 or Falcon 9R, it would be useful to understand the ...
geoffc's user avatar
  • 79.2k
8 votes
1 answer
168 views

How are current spacecraft tested for their impact durability?

I imagine the lift-off process itself puts a large amount of stress and strain on the rockets materials. With the amount of debris up in space there is always the risk of rocks to collide with the ...
user avatar
9 votes
1 answer
139 views

How are (robotic) government space exploration missions in Japan initiated?

The process of how a "government space mission" is initiated is kind of an interesting question to me. In the US and Europe, one has to deal with a series of institutions, agencies, politicians, write ...
s-m-e's user avatar
  • 6,561
11 votes
2 answers
2k views

Alternatives to centripetal force and constant acceleration to simulate Earth-like gravity

This is follow-up to @Erik's answer to the question Is artificial gravity feasible in manned long-term space exploration? I'm curious, whether there's any alternative methods to simulating effects of ...
TildalWave's user avatar
  • 75.9k
13 votes
2 answers
567 views

What is the optimal selection for a small self sustaining space farm?

There are a multitude of resources about growing food in space, NASA research indicates we have been growing foods in space for years. Colonies in Space by T. A. Heppenheimer seems to have some ...
James Jenkins's user avatar
26 votes
4 answers
12k views

Is there any advantage in launching spacecraft from a high latitude, or why was Plesetsk built so far north?

For launching satellites or other spacecraft, there is a significant advantage in being close to the equator: angular momentum helps in gaining initial speed and one can launch into any inclination. ...
gerrit's user avatar
  • 11.5k
25 votes
3 answers
4k views

What is the smallest number of humans required for colonization?

There is an estimate at Understanding Genetics that the minimum number of humans required for a colonization process is 160. It also mentions some animal populations that have rebounded from near ...
James Jenkins's user avatar
7 votes
2 answers
220 views

Would a biological resource-system be feasible for long-term manned flights?

Supposing a long-term manned flight is planned would a biological resource-system be considered as an option? Would a biological resource-system work or is a technical solution superior? Currently ...
bastik's user avatar
  • 1,237
2 votes
0 answers
35 views

Is it better to build a spaceship in total or in parts for orbital assembly? [duplicate]

Supposing a planned long-term manned-flight with a spaceship that has to be fairly large to accommodate many people and meet some requirements like decent shielding from radiation. Is it better to ...
bastik's user avatar
  • 1,237
13 votes
1 answer
532 views

Is there research for the optimal small crew size for a long space voyage?

There are many factors in planning a long space voyage. The human interaction being one of them. Group dynamics have been studied in detail for naval and other military applications, the stations on ...
James Jenkins's user avatar
13 votes
4 answers
2k views

How would manned interstellar travel become feasible? [closed]

What is the actual feasibility of interstellar travel? For instance, a manned journey to Proxima Centauri, given the distance, what technology would need to be developed/perfected for such a journey?...
user avatar
8 votes
2 answers
732 views

Can a projectile fall into a low Earth orbit?

One of the problems with space flight is the speed required to achieve orbit; 17,500 mph. One of the ways I've always thought to achieve this was to launch at a low speed to a very high altitude then ...
user avatar
6 votes
5 answers
10k views

How to simulate Earth's gravity in future colonies on other planets?

What would be a viable means to simulate and maintain Earth's gravitational acceleration in a future colony built on another planet? I am mainly focusing on terrestrial planets, where a colony could ...
user avatar
17 votes
3 answers
3k views

In a cryogenic fuel rocket, at what pressure is the fuel injected into the engine?

The pressure in the Space Shuttle's main engines must be very high to get the vehicle off the ground (with the SRB assist, of course). With such high pressures inside the engine, how do you inject ...
user avatar
10 votes
3 answers
6k views

How much fuel would one need to launch a 1kg object from 100,000 feet?

Back in the old days of the cold war the US and Russia were trying to develop a Nuclear powered aircraft. Problems with radiation shielding and "safety" held them back. Let's say that they got this ...
user avatar
14 votes
3 answers
3k views

What portion of SpaceX's revenue comes from private sources?

SpaceX is often called a "commercial" company and participates in NASA's Commercial Crew Program. In SpaceX's early days, all of SpaceX's revenue came from non-government sources. But today, SpaceX ...
Erik's user avatar
  • 10.1k

15 30 50 per page