Hot answers tagged

67 votes

Why did the Chinese send flies and plants to the far side of the moon?

Right now, almost 100% of existing research on growth in gravity fields is basically at 0g (ISS/Mir/Skylab/whatever) or 1g. There are a lot of questions of what happens at 1/6g or 2/3g? No good ...
user avatar
  • 76.5k
44 votes
Accepted

How did humans grow plants on the Moon despite the harsh conditions?

While it's still cool, it's not as tricky as it may sound at first: The seeds, including water, are stored in a sealed, heated and shielded container. The container also includes fruit flies and ...
user avatar
  • 12.2k
33 votes
Accepted

Why is there a pregnancy test kit on the ISS?

The test kit is there in case a female crewmember suspects that she might be pregnant. Your second question will never be answered because of US medical privacy laws. For the 3rd question, I have ...
user avatar
31 votes

Why aren't there any robotic missions on Europa or Enceladus?

There are probably many answers, but for guesstimating hypothetical missions a look at delta-V/subway maps like this are highly informative in terms of problem scale. Working from that getting into ...
user avatar
28 votes
Accepted

Why haven't we sent seeds of life to other planets yet?

Planetary protection is the principle that on the contrary to your proposal, we should take steps to avoid any contamination of planetary bodies with life from Earth. There are various cited ...
user avatar
  • 9,929
27 votes

Is there any demonstrated or even proposed technology that can sterilize a spacecraft with 100% certainty and yet leave it electronically functional?

Absolute 100% sterilization is impossible. There's always a tiny chance that some microbe lands on a component during manufacturing, gets entombed inside the packaging, and therefore is unreachable ...
user avatar
  • 46.5k
23 votes
Accepted

Can humans live in something like the ISS around gas giants?

This is a pretty broad questions, as it would depend on which gas giant you have in mind. Excluding Uranus and Neptune as ice giants, this leaves us with Jupiter and Saturn in our own Solar system, ...
user avatar
  • 75.5k
23 votes
Accepted

Why aren't there any robotic missions on Europa or Enceladus?

@GremlinWrangler's answer sums up several important points; Getting a low mass rover from Earth all the way to landing on the surface of one of those Moons requires much much more rocketry (delta-v) ...
user avatar
  • 148k
22 votes
Accepted

What concentration of oxygen in a planetary atmosphere would be indicative of life?

I would argue that no specific level of molecular or atomic oxygen in atmosphere is indicative of carbon-based life (i.e. life as we know it on Earth). A planet could have oxygen rich atmosphere which ...
user avatar
  • 75.5k
22 votes

Can a launch of a rocket or ship from Earth go so badly that it damages the Solar System?

No. Look at the numbers: ...
user avatar
  • 12.2k
22 votes

Why is Curiosity not heading for Peace Vallis?

It is actually too likely to find water there. There are 3 categories of Planetary Protection missions for a mission to Mars, IVa, IVb, and IVc. Curiosity meets the IVa criteria, a mission not ...
user avatar
  • 118k
21 votes
Accepted

Are there free insects in the ISS?

Jared Olson, robotics instructor and flight controller at Johnson Space Center, claims not, and as an entomologist I think that's actually plausible. It sounds like there are extensive quarantine and ...
user avatar
21 votes
Accepted

Did Streptococcus mitis survive 950 days in the lunar environment?

Yes, viable Streptococcus mitis was found on the Surveyor 3 camera returned by Apollo 12. This is described in the report Analysis of Surveyor 3 materials and photographs returned by Apollo 12 (25 Mb,...
user avatar
  • 46.5k
17 votes
Accepted

Have there been experiments in space to determine how plants grow without any gravitational or light cues for direction?

Seeds include a plant embryo with a root and a shoot already developed. When the seed germinates, the root and the shoot each elongate through tissue growth at the tip (meristem). Without ...
user avatar
  • 46.5k
17 votes

Is there any demonstrated or even proposed technology that can sterilize a spacecraft with 100% certainty and yet leave it electronically functional?

No, it is not possible to make it 100% sterile. Especially if you consider self-replication as only requirement to classify something as life (It's complicated. See obligatory xkcd reference) Few ...
user avatar
16 votes
Accepted

Can a launch of a rocket or ship from Earth go so badly that it damages the Solar System?

First, some perspective. The impact of a single fragment of the Shoemaker-Levy comet on Jupiter released an estimated energy equivalent of six million megatons of TNT (approximately 600 times the ...
user avatar
  • 2,210
15 votes
Accepted

What is meant by 'Organics' when discussing space exploration?

'Organics' usually refer to organic compounds. From Wikipedia: http://en.wikipedia.org/wiki/Organic_compound There is no single "official" definition of an organic compound. Some textbooks ...
user avatar
  • 7,088
15 votes
Accepted

Have water bears ever been studied on the ISS or in Space?

They have been flown on the FOTON-M3 mission... In 2007, three projects were conducted during the FOTON-M3 mission studies. The Tardigrade Resistance to Space Effects (TARSE) Project was the ...
user avatar
14 votes

What existing life on Earth is best suited for the Martian environment?

There is a chamber at the German Aerospace Center designed to imitate the Martian environment. So far there are two published experiments showing that some organisms could survive in the chamber. An ...
user avatar
  • 20.8k
14 votes
Accepted

How certain are we that we have not accidentally sent life to other planets/moons?

First of all, rocks from Earth are probably just about everywhere in the Solar System. One simple example is this rock found on the Moon. A number of pieces of Mars have been found on Earth, and if ...
user avatar
  • 118k
13 votes

How would finding life on Mars affect the timeline to send people?

The Outer Space Treaty (signed by the US in 1967) specifies that (Article IX): States Parties to the Treaty shall pursue studies of outer space, including the Moon and other celestial bodies, and ...
user avatar
  • 7,106
13 votes

Agriculture on an exoplanet

Ignoring the infrared radiation aspect of your question, what you are describing is a situation not too dissimilar to what exists in many parts of Australia. The extreme degree of weathering that has ...
user avatar
  • 10.7k
12 votes
Accepted

Largest inhabitable volume in space

So far (2016) the biggest "room" in orbit was the Orbital Workshop of Skylab. Here's a video showing astronauts moving in the largest part of Skylab. You never get to see the "floor&...
user avatar
  • 12.2k
12 votes

What is the maximum atmospheric pressure a human can tolerate?

The answers are found in the SCUBA diving world. Diving is interesting in this sense in that 10m is roughly an increase in pressure of 1atm. In general, you wont see humans doing well above 30atm. ...
user avatar
  • 1,834
12 votes

Does SpaceX plan to enhance/change the genome of space colonists to speed up the adaptation process to the living conditions on Mars?

No. SpaceX is a space launch company, not a genetic engineering company. That branch of science lies completely outside their research. Never mind the ethical aspect: the astronauts are volunteers, ...
user avatar
  • 52.6k
11 votes
Accepted

Melanized fungi on the ISS - are they 'enjoying' the elevated radiation levels there?

The experiment Growth and Survival of Colored Fungi in Space (CFS-A) - 12.07.16 showed that: fungi can grow inside the space station and could decompose food and other organic materials in humid ...
user avatar
  • 23.5k
11 votes
Accepted

Could a molecular cloud be breathable?

Not a chance. Those "clouds" are a vacuum, but just a vacuum that has a few more particles than outside those "clouds". The density of those "clouds" around 1–100 particles per cm³. You can't ...
user avatar
  • 11.2k
10 votes

What is meant by 'Organics' when discussing space exploration?

What is meant by 'Organics' when discussing space exploration? It means compounds that contain carbon, except possibly for some simple carbon compounds such as CO2, carbonates and cyanides that ...
user avatar
  • 64.2k
10 votes

What concentration of oxygen in a planetary atmosphere would be indicative of life?

As @TidalWave said, no specific level of oxygen is by itself sufficient to potentially indicate life. However, based on this article, what astronomers are looking for is the combination of both ...
user avatar
  • 574
10 votes

How would finding life on Mars affect the timeline to send people?

If life is found on Mars, NASA does not have anything that would suspend travel to Mars. However, NASA does have a NPD: Biological Contamination Control for Outbound and Inbound Planetary Spacecraft ,...
user avatar

Only top scored, non community-wiki answers of a minimum length are eligible