All Questions
Tagged with exoplanets exoplanets or
122 questions
78
votes
6
answers
10k
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How can we see planets thousands of light years away but don't know if there are more planets in the solar system?
That is basically my question, it arose when I saw an article (here is the scientific paper, which should be free to read) saying two Caltech scientists might have found the 9th planet of the solar ...
- 1,768
43
votes
2
answers
7k
views
Is our solar system really that odd?
I have been learning about the solar system from popular science shows. In these shows they suggest that, after having seeing around 2500 other solar systems, astronomers have concluded that our ...
- 1,430
26
votes
4
answers
3k
views
How do the “hot Jupiter” planets get so close to their host star?
Many of the extrasolar planets to date are Jovian sized planets that orbit very very close to their parent star. Traditional planetary formation models say that it is extremely unlikely (if not ...
- 6,467
20
votes
1
answer
2k
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Can we know if an exoplanet has a magnetic field?
The recent discovery of the exoplanet Proxima b gave rise to several questions concerning its habitability and its potential to host life. A major concern is the huge amount of radiation coming from ...
- 1,264
16
votes
3
answers
2k
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What is the probability that a star of a given spectral type will have planets?
There is a lot of new data from the various extrasolar planet projects including NASA's Kepler mission on extra-solar planets. Based on our current data what is the probability that a star of each of ...
- 6,467
15
votes
2
answers
2k
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What is the farthest planetary body or star system object we have observed using visual light?
What is the farthest object which we can get a direct Detailed visual image of using visible light which appears more than just a dot and falls into one of the following categories:
Planet
Satellite
...
- 838
14
votes
1
answer
2k
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Do any naked-eye stars have planets
Are there any known exoplanets around naked-eye stars? I know that Fomalhaut has a planet, and Vega has a dust belt that may be a protoplanetary disk or even analogous to our Kuiper belt. What else is ...
- 4,543
14
votes
2
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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 ...
- 3,662
14
votes
2
answers
691
views
Why did population III stars lack planets?
Jay Wacker1 (professor of physics at the SLAC National Accelerator Laboratory) stated:
The first stars (known as Pop III) were made out of hydrogen and helium. They had no planets.
Why couldn't ...
- 2,350
14
votes
2
answers
2k
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What would we see if we looked at our Solar system from 2,000 light years away with our current technology?
Assuming the tables were turned and we would live in a system like Kepler-422/423/424, some 2,000 ly away. If we'd look at the Solar system with a telescope like Kepler and using techniques like ...
- 209
11
votes
1
answer
629
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How many earth-sized planets have been discovered outside the solar system?
How many earth-sized planets have been discovered outside our solar system? Is there a combined registry of them anywhere? Where might I look for more information?
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10
votes
2
answers
2k
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How can a gas giant be about the same size but six times more massive than Jupiter?
I've just read this article: http://www.sci-news.com/astronomy/science-kepler-432b-new-super-jupiter-exoplanet-02490.html
And I wondered how this could be possible?
Maybe it's because this gas giant ...
- 1,643
10
votes
2
answers
138
views
Planets capable of life: dead or still alive?
There are some planets that scientists speculate may be capable of supporting life. However, these planets are hundreds of light years away. How can we be sure they are still capable of supporting ...
grassman
10
votes
2
answers
315
views
How close would Earth have to be for us to detect it was habitable, and then inhabited?
Given our current technology (or technology that is near implementation), how close would a clone of our Solar System (and so also Earth) have to be to us in order to detect that the cloned Earth was ...
- 6,987
9
votes
3
answers
5k
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Are we capable of discovering planets in the Andromeda galaxy?
I just watched this SpaceRip video on YouTube which shows pictures taken by Hubble while looking into the disk of the Andromeda galaxy to study a certain type of variable star. It occurred to me that ...
- 5,091
9
votes
3
answers
1k
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Why is planet CFBDSIR2149-0403 hot?
According to a BBC report
Astronomers have spotted a "rogue planet" - wandering the cosmos without a star to orbit - 100 light-years away.
...
The proximity of the new rogue planet has ...
- 7,308
9
votes
2
answers
299
views
Word for the star around which an exoplanet orbits:
Is there accepted nomenclature for the star around which a particular exoplanet orbits? Meaning, if I were to say "The exoplanet blah blah blah's (noun)" what noun would I put there? Sun? Star? ...
- 147
8
votes
5
answers
221
views
Exoplanet detection via space-based parasol
I remember from watching Cosmos years ago, Carl Sagan suggested an interesting hypothetical method for directly seeing exoplanets. He proposed that in the 'future' we could launch a satellite designed ...
- 727
8
votes
3
answers
359
views
Is a rogue 'exoplanet' classed as a exoplanet?
Given that the term planet strictly (according to the IAU) refers to a body around the sun, rogue planets can't be called that, so I assume they must be called rogue exoplanets?
But do they even ...
- 6,987
8
votes
1
answer
4k
views
What is the percentage of stars with planetary systems
We have discovered quite a number of exoplanets to date. The Kepler spacecraft has examined 150,000 stars and found 1,059 exoplanets.
We know that Kepler, as well as all other exoplanet searches to ...
- 11.2k
7
votes
2
answers
510
views
Earliest terrestrial planet?
If I've understood correctly, the heavier elements needed for terrestrial planets such as iron can only form in supernova.
If that is indeed true, how long since the beginning of the universe would ...
- 692
7
votes
1
answer
332
views
How are exoplanets confirmed?
In reference to the Kepler 22b news:
The Kepler team had to wait for three passes of the planet before
upping its status from "candidate" to "confirmed".
This is possible because the planet has ...
- 6,987
7
votes
1
answer
420
views
Are there rogue planets between Sun and Proxima Centauri?
Would we be able to detect (via emitted radiation, or its gravity) a rogue planet between us and Proxima Centauri? How big would that planet need to be?
- 275
7
votes
1
answer
1k
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Stability of moons around tidally locked exoplanets
Can someone send me pointers to work (either theoretical or simulations)
showing (in)stability of satellite orbits around tidally locked exoplanets?
I want to know firstly if satellite orbits can ...
Kamal Ali
7
votes
0
answers
113
views
Are there certain alignments in planetary orbits that create interesting effects in the moons or planets? [closed]
We have some interesting examples such as Mercury's perihelion
The planet Mercury is especially susceptible to Jupiter's influence
because of a small celestial coincidence: Mercury's perihelion, ...
- 3,662
6
votes
2
answers
1k
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How does rogue planet PSO J318.5-22 stay 800ºC?
According to this article, the rogue planet (meaning a planet which does not orbit a star) PSO J318.5-22 has a surface temperature of 800ºC and weather that features molten iron rain. Without a star ...
- 738
6
votes
0
answers
115
views
are alignment of star systems' orbital planes with ours better than random?
It obviously helps our observation of exoplanets if they transit their star from our point-of-view. I would guess that the chances of this alignment are better than if their orbital plane was randomly ...
- 161
5
votes
1
answer
135
views
Is there an established standard for naming exoplanets?
I understand that exoplanets are named by adding a lowercase letter to the a designation of the planet's parent star or stellar system, beginning with 'b' (the star itself is 'a') in order of ...
- 5,169
5
votes
1
answer
167
views
Are the known exoplanets representative of the population of exoplanets?
An article about the recent release of a large number of confirmed exoplanets states that most of the 715 newly announced exoplanets orbit very close to their host stars.
Do the theories predict ...
- 16.7k
5
votes
2
answers
456
views
Exoplanet surface detail: Limitations on size of space telescope array
How big could an array of space telescopes acting as an interferometer be ?
How big would it have to be to resolve exoplanet surface detail the size of Iceland at a distance of 100 light years ?
- 151
4
votes
2
answers
946
views
Sodium sometimes absorbs orange-yellow light, sometimes emits it? Huh?
Usually, we are told that sodium emits orangish-yellowish light, which is why city streetlamps are that color.
Now, I read in New Scientist magazine that exoplanet WASP-96b is bluish because the ...
- 4,709
4
votes
2
answers
184
views
Is it possible to get to get to Proxima B in 30 years?
This morning I read about the discovery of an earth-like planet, Proxima B, being 'just' 4.22 light years away from us. This is quite interesting since the planet is oribiting our closest neighbour.
...
- 143
4
votes
2
answers
227
views
Is it possible that only one hemisphere of a planet has an atmosphere?
Suppose there is a tidally locked planet orbiting a star. The planet's surface consists of a global ocean, that is, liquid water. At the inner hemisphere the temperature is so high that the water is ...
- 11.3k
4
votes
1
answer
94
views
Do stars of higher metallicity have more planets in highly-inclined Pluto-like orbits?
In an answer to a previous question of mine, one that asked about the planar orbits of inner planets, I was told the following (emphasis mine):
On the subject of different solar systems, I would ...
- 3,662
4
votes
1
answer
45
views
Contents page of Exoplanets book
I can't find an online contents page for the book Exoplanets, edited by Sara Seager, University of Arizona Press, 2011.
Can you point to such a page, or say what the contents page says?
Qurq
4
votes
2
answers
208
views
Are there planets orbiting something else than a star?
Exoplanet is a planet that orbits a star different from our Sun.
Are there any planets (that we know of) which orbit something else? (Like different giant planet or black hole or maybe neutron star.)
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4
votes
2
answers
52
views
Is it easier to learn more about the seasonal changes in an exoplanet's atmosphere when the exoplanet orbits a binary star system?
From a recent ScienceDaily article, we have this...
Scientists detected the new planet in the Kepler-16 system, a pair of
orbiting stars that eclipse each other from our vantage point on
Earth. When ...
- 3,662
4
votes
1
answer
297
views
What would be the color of a deep, pure and vast liquid $\rm CO_2$ ocean if viewed from space (ignoring the atmosphere's influence)?
So far I had no luck trying to find the visible absorption spectrum of $\rm CO_2$ anywhere, all I get is the far infrared absorption spectrum and stuff like that.
If you just search "what color ...
- 43
4
votes
1
answer
536
views
What day/night cycles, climate and seasons would experience Alpha Centauri Bb inhabitants?
Alpha Centauri Bb is an exoplanet orbiting Alpha Centauri B. It is asserted that given the close distance to the star the planet should be tidally locked.
The orbiting period of the planet is about ...
- 11.3k
3
votes
2
answers
548
views
Is it possible, by monitoring the brightness of stars, to find a “copy of the Earth + Moon” near them?
More than a dozen Earth-like planets have been discovered around nearby stars based on observations of changes in the brightness of their sun as they pass across its disk (transit events). If an Earth-...
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3
votes
1
answer
2k
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How is the stellar flux for exoplanets calculated?
I have noticed that in many Wikipedia articles, the stellar flux received by each planet is stated. I tried to calculate this stellar flux from the given data, but the results didn't seem to be ...
- 3,934
3
votes
1
answer
79
views
Is CO2 really a potent greenhouse gas for planets around M dwarfs?
The thing with global warming is that it absorbs infrared (IR) radiation from the planet and reradiates much of it back to the planet (whereas the Sun's peak flux is in the visible region, that is ...
- 3,662
3
votes
2
answers
218
views
Is angular resolution important when we want the spectra of an Earth-like exoplanet?
Right now, our resolution + light gathering power are still far too low to take direct images of exoplanets, so we're limited to subtracting the planet spectra from the parent star spectra when the ...
- 3,662
3
votes
3
answers
2k
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Lift and drag coefficients on other planets
The question I'm trying to answer seemed simple: how hard would it be to fly on a planet with lower gravity but also thinner atmosphere compared to Earth. If the answer could hint me at how much ...
- 33
3
votes
1
answer
728
views
Exoplanet Mass-Radius Diagram
I'm currently studying the following diagram:
But I'm not entirely sure I understand what's going on. Is it just, that most exoplanets discovered, is pretty much made up of Hydrogen and Helium ? And ...
- 2,577
3
votes
3
answers
255
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Simulation of relativistic probe passing through an external solar system
I recently read about the Breakthrough Initiative to launch "StarShot", a nano-probe that is designed to travel to Alpha Centauri at $0.2c$. One of the challenges to be solved involves the precise ...
3
votes
1
answer
87
views
Have we observed sufficient extra-solar planetary systems to establish a planetary distribution pattern? [duplicate]
From Kepler And Extra-Solar Planetary Observations
As of January 2015, Kepler and its follow-up observations had found 1,013 confirmed exoplanets in about 440 stellar systems, along with a further ...
user81619
3
votes
1
answer
103
views
What could this very dark planet be made of?
I was reading about the planet TrES-2b which is less reflective than charcoal. What could possibly be its composition?
- 6,082
3
votes
1
answer
312
views
If a hot Jupiter was not tidally locked, then are there any specific cases where its wind speeds would be milder than those found on Jupiter?
If a hot Jupiter was not tidally locked, are there any specific cases where its wind speeds would be milder than those found on Jupiter?
After controlling for the age of the hot Jupiter, of course. ...
- 3,662
3
votes
4
answers
401
views
Gas giant evolution over lifetime
In various types of stars, one can learn how they evolve differently, depending on factors such as their size and chemistry. Some stars have a short lifetime and others much longer.
But, what is ...
- 53