Questions tagged [exoplanet]
Questions regarding planets that lie outside the Solar System.
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how far away could we detect that Earth has life?
My guess is that life bearing planets are too far apart to be detected. I think we can only find the ones within a sphere around our planet that is 100s of light years in diameter but I suspect life ...
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Is it possible that the Sun has a binary partner (the Nemesis Theory) that has eluded detection? [duplicate]
I just recently learned about the theory that our Sun has a small companion star with a 26 million year orbit. This theory came about when it was realized that mass extinction events happened ...
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If Alpha Centauri A's solar system exactly mirrored our own, what would we be able to detect?
Suppose there was an exact replica of our solar system 4.4 ly away (people included). What would we be able to detect and with what telescope(s)? Which planets? Could we detect radio transmissions and/...
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Just how "locked" are resonant-chains of exoplanets thought to be? (e.g. K2-138 and TOI-178)
The Phys.org news item Discovery of new planet reveals distant solar system to rival our own outlines the recent announcement of results using AI to help search Kepler photometric (transit-method) ...
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Terrestrial Exoplanet Skies – I've Built a Visual Sky Chart. Is it Accurate?
I'm an artist (and science enthusiast) and I've been trying to find a comprehensive resource that would help me clearly identify likely sky colors (as perceived by human vision) for exoplanets that ...
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Detection of exo-planets
One method used for detecting exo-planets is to look for a slight dip in the parent star's luminosity as the planet transits the stellar disc. Intuitively, it seems to me that if planetary systems in ...
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Where did TRAPPIST-1a go?
According to the NASA announcement and the Wikipedia article on TRAPPIST-1, the planets around the TRAPPIST-1 star are named TRAPPIST-1 b through h. What happened to "TRAPPIST-1 a"?
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Is the closest planet to another planet always the innermost planet?
In our Solar system Mercury is not only the closest planet to Earth on average but also, for the same reason, the closest planet on average to all other planets (Jupiter, Neptune, etc...).
Does that ...
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What percent of planets are in the position that they could be viewed edge-on from Earth? (and thus able to undergo transits)
Star number 12644769 from the Kepler Input Catalog was identified as
an eclipsing binary with a 41-day period, from the detection of its
mutual eclipses (9). Eclipses occur because the orbital ...
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After only one eclipse of its X-ray bright primary, how can astronomers estimate the first extragalactic exoplanet's period to be about 70 years?
Phys.org's Astronomers may have discovered the first planet outside of our galaxy links to Di Stefano et al. 2021 A possible planet candidate in an external galaxy detected through X-ray transit (...
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Can SETI certify whether or not Proxima b is inhabited by beings using electromagnetic communication?
Can SETI certify whether or not Proxima b is inhabited by beings using electromagnetic communication?
By certify I mean by past, present or future observations using technologies available.
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How to find Exomoons?
How would we be able to detect Exomoons? We detect exoplanets by seeing if the light gets faint from a star, but could we really use the same method for determining if there is an exomoon around that ...
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Is there an upper limit to the mass of terrestrial planets?
The exoplanet Kepler-10c has a mass between 15 and 19 times the mass of the Earth (making it comparable in mass to Neptune), and yet is thought to have a density of about 7g/cm3 and to be a ...
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What's still needed before we can observe orbits of exomoons thereby weighing exoplanets?
Comments below this answer to How do we weigh a planet? point out that we currently cannot (or at least have not) detect moons around exoplanets, much less measure the sizes and periods of their ...
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Why does the exoplanetary system TOI-178 challenges current theories of planet formation?
I am excited reading the news about ESA's latest exoplanet discovery using CHEOPS. The system TOI-178 consists of (at least?) five planets, following a 18:9:6:4:3 pattern. In the press release, the ...
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Are the planets in the TRAPPIST-1 system so close that inhabitants on one planet could see surface details on the other planets?
In a discussion below the Space Exploration question Are there any to-scale diagrams of the TRAPPIST-1 system I was invited to ask a question like this, so I have.
Question: Are the planets in the ...
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How are the compositional components of exoplanet atmospheres differentiated?
How are exoplanetary atmosphere compositional spectra distinguished from those of the parent star(s), from the composition of the planetary surface or any other factor? Is it actually possible to ...
user8
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Do any known exoplanetary/solar bodies have "annular" eclipses similar to Earth's?
This was somewhat inspired by this question but is a bit different: I am interested in if there are any known systems in which the angular size of the eclipsing object is almost the same as the ...
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How would we detect an Earth doppelganger planet?
With our current technology, or technology available in the near future (up to 2025), how would we detect a planet exactly like our own, and how close would it have to be to be detectable?
Which ...
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Orbital velocity of a planet - why is my calculation off by about 10%?
I am not sure if I am doing something wrong, or misunderstanding Reider and Kenworthy (2016).
I'm just trying to reproduce the orbital velocities listed in Table 1. The second paragraph of Section II ...
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Is there enough data in light coming from distant exoplanets for Earth-orbiting telescopes to take a high-resolution photo of it?
NASA’s James Webb Space Telescope has taken very blurry "photos" of exoplanets around distant stars, such as the exoplanet HIP 65426 b, in different bands of infrared light:
My question is, ...
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Could the James Webb Space Telescope detect biosignals on exoplanets?
The James Webb Space Telescope (JWST) which is slated to launch in 2018 will bring us a better view of exoplanets, but will it be sufficient to detect signs of life on at least some of those worlds?
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Why can't we build a huge stationary optical telescope inside a depression similar to the FAST radio telescope?
So first we'll have to find a natural depression or we should create one. I understand you can only see a single portion of the sky since it can't be moved, so my money is on creating an artificial ...
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Why don't we use amateur astronomers' telescopes to create a huge interferometer?
Some telescopes in space have been proposed to function as an interferometer.
Being placed several hundreds or thousands of kilometers apart they could actual image exoplanets directly. To my ...
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Why can we see the Pillars of Creation, but not Proxima B?
I was wondering how is it that we can see the Pillars of Creation (I know they're no longer there too) which are labeled as 6,500 light years away from earth and yet Proxima B is labeled at just 4.2 ...
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What's the name for [the other kind of planet] in a binary star system?
This XKCD what-if talks about rainbows on planets in a binary star system. It points out that there are two types:
circumbinary planets, where the planet orbits far from and around both stars
[the ...
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Are many exoplanets synchronously tidally locked like Mercury?
The only tidally locked planet in the Solar system is Mercury. But it is synchronously tidally locked 3:2, because of the relatively high eccentricity of its orbit, so doesn't turn the same side ...
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How many earth-like planets do we know at this moment?
Well, the title says everything...
How many earth-like planets have we discovered out there?
Discard too big (made of gas), too cold, too hot, etc.
Consider earth-like sun distance, size, temperature, ...
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Explanation about the resonance, mean motion resonance and libration
I am studying for a project the dynamics of multi-planetary system in resonance. I have two questions about this domain.
In many articles they speak about 'mean motion resonance', what is the ...
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Brown dwarfs and planets
As far as I know, a brown dwarf is a 'star' whose core never underwent a fusion reaction, so it never became a star.
So I was wondering if, apart from orbiting a star, is there any difference ...
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How can a Grade-11 Student avail TESS data and learn to process?
As mentioned, I am a Grade-11 student. I have always been interested in Data Processing activities. This sums up my experience of working on Asteroid hunt Campaign under IASC (International Asteroid ...
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Have any co-orbital exoplanet pairs been discovered (and not subsequently retracted)?
For this question, I think a good working definition of co-orbital configuration would be two bodies orbiting around a third much larger body in a 1:1 resonance and where neither mass is negligible. ...
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How often does the configuration of the Trappist-1 system repeat
My question is simply how long it takes for the 7 known planets in Trappist-1 to be in the same configuration in relation to their host star, and to each-other. Those seven planets are in a 2:3:4:6:9:...
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Which studies prior to 2018 "claimed to find evidence of extragalactic planets in the Andromeda galaxy"? Which instrument was used?
After the first round of popular news items about the "first extragalactic exoplanet" discovery, CNET's Did astronomers find the first planet outside of the Milky Way? It's complicated ...
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Is it odd that our Sun has so many planets?
The internet is abuzz with the new evidence of the possible ninth planet in our Solar System. With those nine objects, the asteroid belt, the Kuiper belt, and everything else in our Solar System - the ...
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Which of the planets would be detected if they were exoplanets?
An (almost-)omnipotent being selects the solar system, presses Ctrl+C, and then Ctrl+V several times, creating copies at distances of 5, 500, 50.000, and 5.000.000 light-years away. All in a direction ...
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Is there any planet bigger than a star?
Or a star smaller than a planet?
Which star and planet would be an example of this?
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Hypothetical trans-Neptunian planets orbiting the Sun
The planet HD 106906 b was found at 650 AU from its home star, a star not so different from the Sun. Fomalhaut b is also a young planet that is orbiting very far away from its star.
These two planets ...
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Why are most discovered exoplanets heavier than Earth?
Looking at all discovered exoplanets (4393 exoplanets), I found than only 17 of them (less than one percent!) have masses less or equal to Earth's mass. Why so?
Is it because it is very difficult to ...
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How many sun-like stars are there in the universe?
After yesterday's announcement of the Kepler telescope finding a huge amount of newly observed exoplanets, i saw a headline claiming that as much as 22% of sun like stars in the universe have planets ...
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Is there a gas giant orbiting TRAPPIST-1?
I would like to know if besides these planets, astronomers have discovered a gas planet like Jupiter in this system and if on these planets could exist life without a comet protector like Jupiter does ...
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When will we be able to detect Earth-sized exoplanets?
I have heard that the only planets able to be seen outside the Solar system are Jovian-sized planets with the occasional detection of planets three times the Earth's size. But, as far as I know, we ...
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Is it possible for a moon to orbit a planet floating free in the galaxy rather than orbiting a star
This article got me thinking, can a planet hold a moon in orbit if it is just floating in the galaxy by itself not as part of a star system? Can a celestial body even qualify as a planet if it is ...
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Would an exoplanet without axial tilt have no seasons?
Would an Earth analog exoplanet which rotates around a solar analog, but without axial tilt, have no seasons?
Would it be similar to how Los Angeles does not have very noticeable seasons compared to ...
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Is the measurement of distance and position of remote celestial bodies accurate?
Considering that light is affected by gravity, how accurate are measurements of distant stars and galaxies?
When light passes through objects with great mass, such as Jupiter size planets, stars, or ...
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Why hasn't VLBI been used to try and image giant exoplanets?
A Jupiter-sized object at 10 pc subtends an angle of 0.0001 arcseconds (100 micro-arcsec) at the Earth. The Event Horizon Telescope interferometry network is capable of a (demonstrated) angular ...
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What are the challenges in finding Earth-like planets via the radial velocity method?
[I have re-asked this, because it was a good question by @Banyan, which was deleted whilst I was composing an answer.]
Most exoplanets that are found by the radial velocity ("Doppler wobble")...
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How would water-ammonia oceans behave?
Scientists strongly suspect that several moons in our solar system have frozen-over oceans of water-ammonia mixture. I've also read speculations on the possibility of surface water-ammonia oceans on ...
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How actively is Deep Learning being used in exoplanet identification?
Papers, like this one from Google, show that Deep Learning and Machine Learning are effective in detecting exoplanets from luminosity data provided by telescopes like TESS or Kepler.
These models ...
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What precisely leads to planets like COCONUTS-2b to orbit so far away from their host stars, 6000 AU in its case?
Taking our Solar System as an example, most gas giants formed relatively close by (a few AU) and drifted away to reasons I don't know, from an explanation I recall reading. Simply orbiting a few AU ...
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