66 votes

Why doesn’t NASA build its rockets using graphene?

The Technology Readiness Level (TRL) of graphene is at 2 or 3 as far as I can tell. And that is TRL as related to making very tiny stuff. Anything used to build a structure for aircraft or spacecraft ...
  • 2,471
40 votes

Why doesn’t NASA build its rockets using graphene?

Besides the fact BradV pointed out that we don't have the technology to do this yet, the fact is that graphene on a macroscopic scale would not perform as well as the numbers you cited suggest. All ...
  • 7,216
30 votes

Why doesn’t NASA build its rockets using graphene?

Many processes being used to make graphene only yield small and irregularly shaped flakes with a lot of defects. The size of those flakes is barely enough to render them visible for the naked eye, and ...
  • 1,015
27 votes

What is the rarest launch window?

Comet West with its unpredictable but estimated at 558 000 years period is a good contender. Since launch windows can aim for the alignment of N objects, the answer obviously tend to infinity. You ...
  • 12.2k
26 votes

Is there something inherently more difficult about servicing satellites in the 2nd Sun-Earth Lagrangian point?

Distance certainly is a key factor. It took JWST a month to go from launch to L2 pseudo-orbit insertion. Another key factor is that to date, the only successful satellite servicing missions have been ...
  • 65.9k
24 votes
Accepted

What landings beyond Mars and the Moon are scheduled?

Feel free to edit this answer to add more or adjust formatting. List may be incomplete. Ordered by launch date: Hayabusa 2 and MASCOT to 162173 Ryugu, Japan/Germany/France, launched 2014, landed ...
21 votes

What is the rarest launch window?

Hohmann launch windows occur each synodic period. Or a more general version of a Hohmann transfer would be a transfer orbit tangent to both departure and destination orbits. This also occurs each ...
  • 15.2k
20 votes
Accepted

Has there ever been crewed mission plans by any Space Agency to go to a solar system object other than the Moon and Mars?

Yes, NASA did consider a crewed flyby of Venus using Saturn/Apollo hardware. This is discussed in another QA on this site. There wasn't much point in doing it, as it would have been several months of ...
20 votes

Is there something inherently more difficult about servicing satellites in the 2nd Sun-Earth Lagrangian point?

Getting to L2 in a timely fashion is more challenging than going to the Moon. The Apollo missions took about 3 days to get to the Moon. 4.5 days is how long the LRO took to orbit the Moon when ...
  • 119k
18 votes
Accepted

Why doesn't NASA create targeted campaigns for donations?

Per https://standards.nasa.gov/documents/viewdoc/3315318/3315318 . NASA Policy Directive COMPLIANCE IS MANDATORY NPD 1210.1G Effective Date: April 28, 2010 Subject: Acceptance and Use of Monetary ...
  • 1,408
17 votes
Accepted

Can double deck spacecraft be designed and constructed for manned missions?

Yes. They can be designed. Big Gemini was a seven-person capsule design that took a two-seat Gemini capsule: (Note: this image shows both the capsule (the black part) and the service module (the ...
  • 10.1k
16 votes
Accepted

Are there any planned extra-solar missions by NASA or others?

You are forgetting Pioneer 10, Pioneer 11, and New Horizons. Pioneers 10 and 11 respectively operated for 28 years and 16 years after completing their primary missions. New Horizons, which has yet to ...
  • 65.9k
16 votes
Accepted

What is the rarest launch window?

The launch of New Horizons was very critical. The NASA scientists had 5 years to develop a space probe to Pluto and make sure it got a gravity assist through Jupiter, which is only possible if ...
14 votes
Accepted

Is there any independent evaluation/report on the feasibility of SpaceX going to Mars by 2024?

I don't have any independent evaluations on hand but it is almost completely certain that SpaceX will not have any rockets landing on Mars in 2024 or leaving for Mars in 2024. Launch windows aren't ...
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14 votes

What are and could be all the advantages and disadvantages to have a crewed station on Phobos before landing crewed missions on Mars?

Establishing a human presence on Phobos would require development of a vehicle specifically for that purpose. Such a vehicle would have a far larger fraction of its arrival mass devoted to propellant ...
12 votes
Accepted

Is there any chance of a US based astronaut launch prior to 2017?

Currently the US has a policy against participating with China in any space endeavors ("Due to U.S. obstruction, China now can only have limited international exchanges and cooperation on space ...
  • 23.7k
12 votes
Accepted

Are there currently any plans for a Venus lander?

NASA's New Frontiers program has been calling for a Venus lander (Venus In Situ Explorer) on every solicitation. Venus landers are proposed every time, sometimes making it to Step 2 in the ...
  • 57.9k
12 votes
Accepted

Why do larger and newer rockets not use electric pumps?

Ultimately the pump, whether electric or combustion-turbine driven, needs a certain amount of total energy input to do its job. Combustion reactions both deliver more total energy per mass than ...
11 votes

Are there currently any plans for a Venus lander?

The Russian Venera missions 9 (1975), 10 (1975), 13 (1982), and 14 (1982) all took images of the Venusian surface. Venera 13 and 14 took color images. Russia is also planning another Venera mission ...
  • 7,084
11 votes

What would be merits of placing space telescope after the asteroid belt or closer to the Kupier belt?

Very little upside, lots of downside. It's colder out there, which means that keeping your IR sensors cool is a bit easier. The orbit is wider, so you get more parallax, but the orbit is slower, so ...
  • 1,393
10 votes
Accepted

One year Mission: Using data from Valeri Polyakov?

The Russian medical monitoring of long term flight participants was not considered well done by the rest of the worlds medical establishment. The ISS has much more equipment, resources, and crew time ...
  • 76.9k
10 votes
Accepted

Good year for start of an interstellar mission, due to gravity-assist

An interstellar mission does not need to visit more than two planets, since your interest by definition lies in objects beyond the Solar System. The Voyagers were first and foremost planetary ...
  • 11.4k
10 votes
Accepted

What are and could be all the advantages and disadvantages to have a crewed station on Phobos before landing crewed missions on Mars?

This NASA paper explores some of the rationales and implications of using Phobos as a staging point for human Mars surface missions. The conclusion is stated in the abstract: Results from this ...
  • 936
9 votes

How feasible would it be to move the ISS to the surface of the Moon to recycle its components in future?

Supplementary answer expanding on @PearsonArtPhoto's answer. The first part of getting ISS (or anything else) from LEO to the Moon is lifting it's orbit around the Earth (or at least one end of its ...
9 votes

Does it make sense to invest money on space investigation?

"We should wait for all the problems on earth to be solved before going into space". I've seen this sentiment multiple times, and I disagree vehemently. 1. There are other much more worthy targets ...
  • 6,205
9 votes
Accepted

Are they already planning a successor to the JWST?

See the Launch Pad Astronomy video 4 Future Space Telescopes NASA wants to build linked below. The notes say that the four ...future space telescopes NASA wants to build are the: Habitable Exoplanet ...
  • 148k
8 votes

What would be the delta-v of rendezvousing with temporarily captured asteroids in Sun-Earth L-points?

Above are 4 ellipses. They all have a 400 km altitude perigee, but widely varying apogees. The blue ellipse has an ~1.5 million km apogee, about the distance to SEL1 or SEL2. The larger grey ellipse ...
  • 15.2k
8 votes

Why doesn't NASA create targeted campaigns for donations?

To expand on the currently accepted answer: The "unconditional gifts only" rule is not NASA-driven policy, it's a matter of federal law. Specifically, three laws control this. The Miscellaneous ...
  • 443
8 votes

Is a one-way manned mission to Mars currently possible?

Getting back is not impossible, just very expensive. This site has a good explanation of the phenomenon.
  • 122k
7 votes

Could the ISS be propelled to Mars?

The ISS is not designed for the kind of high thrust to escape Earth orbit, nor the duration of time it would take. The ISS is not designed to operate far from Earth, as it requires constant resupply....
  • 76.9k

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