29 votes
Accepted

Are images of exoplanets' surfaces technically possible?

With a resolution of 1E-09 radians, Jupiter would be 1 pixel wide at 7 light years. If you had 1E-10 radians, you could resolve the largest features. Visible light has a wavelength of 5E-07 meters, ...
uhoh's user avatar
  • 149k
26 votes
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Why would Kepler rotate towards Earth to transfer data?

Kepler has a parabolic dish antenna fixed to its body. There are many possible designs of transmitting devices. For spacecraft, parabolic dish antennas are preferred, because they have the least ...
Heopps's user avatar
  • 9,071
21 votes

Can a meteor shower have a interval greater than 1 year?

This is really more of a question for Astronomy.SE, in general this doesn't happen, but circumstances can work out that it does, see the updated last few paragraphs. Every meteor shower with an ...
notovny's user avatar
  • 5,439
14 votes
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Why is TRAPPIST-1f considered habitable?

None of the TRAPPIST-1 planets are "considered habitable"; we don't know nearly enough about them to say that (any news article which referred to the planets themselves as "habitable" needs firm ...
Russell Borogove's user avatar
13 votes

Dark side of an exoplanet - if it was earth-like would its surface light be detectable?

Keep in mind that earth like exoplanets are mostly found as they cross in front of their sun. If you hold a flashlight between you and the sun, you would not be able to tell if it was on or off, ...
James Jenkins's user avatar
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 ...
Fred's user avatar
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12 votes
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When will we be able to conclusively confirm or disprove Bode's law?

I would argue that it is disproven already. There have been studies done with Extrasolar planets, and it has been found to only apply in a very small number of instances. There might be some that ...
PearsonArtPhoto's user avatar
  • 121k
11 votes

A Jupiter-sized star?

Jupiter is about as large as a planet can get, physically. Suppose we slowly add hydrogen and helium to Jupiter, so slowly so as to keep it at more or less its current temperature. Surprisingly, it ...
David Hammen's user avatar
  • 74.8k
9 votes

Would an interstellar exoplanet telescope make sense?

@SF. is right. It is true that a location far from Earth could have access to different orbital planes and thus potentially see a different set of occultations an transits, you would have to move very ...
uhoh's user avatar
  • 149k
9 votes

How to calculate density of unknown planet?

Planets are usually rotating, and so you can't time two passes over a single geographical feature to time an orbit. But you can time successive sunrises to get a good approximation of the orbital ...
uhoh's user avatar
  • 149k
9 votes

Dark side of an exoplanet - if it was earth-like would its surface light be detectable?

City lights are not detectable today, but it is possible in the future. It would require: future generations of telescopes on the ground and in space that would have the capacity to detect phase ...
called2voyage's user avatar
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9 votes
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Why are all possibly habitable exoplanets higher mass than Earth?

There is a nice Wikipedia article about the transit method for finding exoplanets by detection of the light intensity drop caused by the planet when passing before its central star. Unfortunately this ...
Uwe's user avatar
  • 49k
8 votes

The gases of technology

The best method of analyzing exoplanet atmospheres is called Transit Absorption Spectroscopy. First, we analyze the spectrum of an exoplanet's star. Then, we wait for the planet to pass in front of ...
Phiteros's user avatar
  • 5,626
8 votes

Why is TRAPPIST-1f considered habitable?

The temperature estimate is based on no atmosphere. For instance, Earth, without our atmosphere, would have an average temperature of -20°C . The equator should be warmer, and any atmosphere will also ...
PearsonArtPhoto's user avatar
  • 121k
8 votes

Could a 21 meter space telescope detect the nearest exoplanets?

As of 2017, 22 exoplanets have been imaged directly. The most distant of those is 1200 ly away. This shows 4 of them orbiting HR 8799, which is 128 ly away: These observations are good enough to ...
Hobbes's user avatar
  • 128k
8 votes
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Can we make super-massive Telescopes to image exoplanets?

So the main thing of interest in this post seems to be angular resolution. You're after objects that are relatively bright and small. Angular resolution increases linearly with aperture size. However, ...
Ingolifs's user avatar
  • 6,458
8 votes

Agriculture on an exoplanet

In general space based plants will probably be hydroponics so most likely initial agriculture will be indoors in vertical farms. Possibly using mechanically harvested/processed materials to carefully ...
GremlinWranger's user avatar
7 votes

Why would Kepler rotate towards Earth to transfer data?

Why would Kepler rotate towards Earth instead having an antenna always directed to Earth? There was no need to always have an antenna pointed directly at the Earth because communication with the ...
David Hammen's user avatar
  • 74.8k
7 votes

Dark side of an exoplanet - if it was earth-like would its surface light be detectable?

Exoplanets are found in a variety of ways. Two rather common ways are star transits and radial velocity changes. Star transits are found by continuously measuring the brightness of the Star, and ...
CourageousPotato's user avatar
6 votes

Are images of exoplanets' surfaces technically possible?

As @uhoh has pointed out, optical interferometers only a little bigger than the ones we have now would allow imaging of large-scale features of large planets around nearby stars. For a more detailed ...
Steve Linton's user avatar
  • 19.6k
6 votes

Can there be an atmosphere in a cave on an atmosphere-less planet?

Yes, in fact it can happen. It happens on Earth to some extent. The term is a "Gas Pocket", and is most commonly associated with oil and natural gas deposits. There are other times of gasses that are ...
PearsonArtPhoto's user avatar
  • 121k
6 votes

When will we be able to conclusively confirm or disprove Bode's law?

Bodes law is a little over stated. It's not a law per se but rather a rule of thumb or a rough guideline It also doesn't work on our solar system exactly. For it to apply perfectly for our system ...
Diesel's user avatar
  • 271
6 votes
Accepted

Exoplanet(s) that share orbit?

Two planets sharing their orbit is expected to be a rare configuration. Most configurations of 2 planets in 1 orbit are unstable. Only when one planet is in a Lagrange point of the other, are the ...
Hobbes's user avatar
  • 128k
6 votes

Would an interstellar exoplanet telescope make sense?

There are several problems with that idea: As mentioned by uhoh and SF, reaching a point far enough away from our solar system to make a different observation than Kepler's takes so much time, that ...
Adwaenyth's user avatar
  • 584
6 votes

How obvious would an Earth-like planet be when searching for signs of life in space?

The predicate of "roughly where Proxima Centauri b is" is a bit problematic. Anything orbiting a star with activity so violent as Proxima is automatically disqualified - the range of ...
SF.'s user avatar
  • 55k
5 votes

What is the origin of Black knight satellite?

I got curious and read this, it makes plenty of sense to me. http://www.jamesoberg.com/sts88_and-black-knight.pdf The suggestion is that many of the photos are really of a bit of space debris from ...
Aaron's user avatar
  • 393
5 votes
Accepted

What is the most accepted explanation to the Fermi paradox by the scientific community?

That's Not How Science Works We don't need an explanation for the Fermi paradox, because we have no evidence that needs explaining. We have a sample size of exactly one when it comes to life in the ...
Dan Hanson's user avatar
  • 2,218
5 votes
Accepted

Agriculture on an exoplanet

There are a lot of specific factors that would be relevant for answering this. Here are a few: What is the composition of the planet's atmosphere? Is there any soil/regolith and what is it made of? ...
N. Virgo's user avatar
  • 329

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