All Questions
Tagged with exoplanets astrophysics
28 questions
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What is a simple way to estimate $σ_{RV}$ assuming photon noise in radial velocity measurements?
Hello there i have been trying to figure out what is wanted in the question "Simple way to estimate σ_RV assuming photon noise" for a presentation. But i can not seems to find much, but i ...
2
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57
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Would ocean tides on the moon of a gas giant really be kilometers high?
I was reading an article on exomoon habitability constrained by illumination and tidal heating. The article imagines an Earth-like exomoon around Jupiter-like host planet. That got me thinking about ...
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1
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619
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Is there a way to calculate/estimate the orbital period of an exoplanet from only one transit detection?
I understand that multiple transit detections of an exoplanet are almost always used to derive its period, but is there a way to do it with only one transit detection? As in, with only one available ...
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Winds or waves in specific conditions?
Winds are mainly produced by differences in temperature of the atmosphere and waves are mainly produced by winds.
However, could a rogue planet (without orbiting any star and with a cold core so no ...
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How to obtain exoplanets transmission spectra from JWST's NIRISS data of WASP96?
I was having a look at JWST's NIRISS data of WASP96 (specifically at the x1dints fits file which should be already calibrated). From this, I would like to obtain a result in a fashion similar to the ...
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2
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219
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Can hot planets host water?
Boiling point of water increases with pressure. If so, can a planet with the right atmospheric pressure contain oceans (made of water) irrespective of its temperature?
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Is the transit technique for exoplanet detections part of the "Wide-Field Precision Photometry Revolution"?
In a exoplanet focused lecture I was informed that the two main techniques for the detection of exoplanets were: radial velocity (VR) and transit. These were very briefly explained to us.
When ...
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1
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Doubt regarding the positioning of starshade in new world's mission of Nasa
The new worlds mission of NASA has an occulter with the telescope, Why did they place the occulter at a distance instead of attaching it to the telescope such that there is a hole as big as the size ...
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208
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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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Research on exoplanets using available data from TESS
I am a high school student who is proposing research on exoplanets for my junior research project, I have several questions:
I have seen studies where researchers survey star systems and then find ...
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When do planets formed via core accretion in a proto-planetary disk stop gaining mass?
I was just trying to go over some of the contents in my exo planets course and wanted to know that if all the planets that form via core accretion continue to attract all the dust in a proto-planetary ...
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Datasets for calculation of exoplanet properties
I would like to create program for calculation exoplanet properties, but I only found transit dataset from Kepler on NASA website. From light curve I can calculate:
planet radius $r$ from $\frac{r_{...
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1
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43
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Can a planemo turn into a star?
I read this question
Why is planet CFBDSIR2149-0403 hot?
and wonder what will happen to this "planemo". Will it attract more mass as it flows around in the gas clouds in space and eventually light ...
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1
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91
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Rayleigh Scattering and Red Giants
Rayleigh scattering is responsible for the color of the sky. Consider a planet with an atmospheric composition similar to Earth's but orbiting a red giant. Suppose further that the planet is in the ...
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Toroidal planetary systems
Is it possible that two toroidal, rigid, homogeneous planets are forming a system in which the toroids are chained through each other, and during their mutual motion, the planets are never touching ...
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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 ...
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1
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256
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What is the difference between habitable and Goldilocks zone?
If I am right, Habitable Zone means that a planet is on such a distance from its Star which makes it good candidate for supporting some sort of life.
But then what is Goldilocks zone and how is it ...
3
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1
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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 ...
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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 ...
3
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1
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728
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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
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2
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297
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Habitable zones around other stars
I have a question about measuring the boundaries of habitable zones on other planets.
Is it okay to assume that, if Sun's habitable zone starts at a distance $R_0$ and its luminosity is $L_0$, we can ...
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1
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189
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Multiple planets orbiting a star
One way of detecting exoplanets orbiting around a star is the Radial velocity method.
Can this be used to detect multiple planets? Wouldn't the star orbit the center of mass of the whole system with ...
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1
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4k
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Is there a simple formula for calculating semimajor axis bounds of "habitable zone"?
I understand that an accurate determination of the bounds of the "habitable zone" for a given stellar system depends on a large number of factors, including many beyond characteristics of the parent ...
5
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1
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167
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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 ...
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510
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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 ...
9
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3
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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 ...
4
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1
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536
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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 ...
7
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1
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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 ...