Questions tagged [exoplanet]
Questions regarding planets that lie outside the Solar System.
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Using the 'exoplanet' module to fit a radial velocity curve for a binary star system
As part of a project, I am trying to fit a radial velocity curve using the tutorial for the binary star system (EBLM J0608-59) My code is quite similar to the tutorial, but as it is only one body ...
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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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Did we find any exo–dwarf-planet?
We have discovered thousands of exoplanets so far. Do we categorize them into planets and dwarf planets, too?
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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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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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Abundance of penitente ice formations in the solar system
When researching for my question on extraterresitral snow, I learned about a rare snow formation called penitente which seems to be found on various (dwarf) planets, like Earth, Mars, and Pluto. ...
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Extraterrestrial snow?
What do we know about extraterrestrial snow? On which (exo)planets or (exo)moons do we have direct hints for its existance? This is indeed a children's question, but I struggle to answer it ...
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Can we visually perceive exoplanet transits with amateur telescopes?
Is it possible for an amateur astronomer to visually perceive an exoplanet transit by the change of brightness of the star via observations spaced over time, or is the variation of the brightness too ...
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Is it possible for planetary rings to be perpendicular (or near perpendicular) to the planet's orbit around the host star?
Is it possible for planetary rings to be perpendicular (or near perpendicular) to the planet's orbit around the host star?
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Calculating the Solar Day of an Exoplanet?
I am currently in the process of compiling a list of stars and their planets, given the information in the European Star Catalogue found here, but I'm struggling to find out how to calculate a planets ...
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Why doesn't star size distribution conform to space rock size distribution?
The number of space rocks is exponentially related to the size of the rocks. There are more small space rocks than big ones. Stars are most commonly the size of the sun, big and smaller stars are rare,...
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Current best-known Drake Equation values?
Frank Drake's equation is used to estimate $N$ the number of civilizations we might be able to communicate with in our galaxy:
$$N = R_\star f_p n_e f_l f_i f_c L$$
where:
$R_\star$ is the average ...
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How difficult is it for an amateur to discover a new exoplanet or astronomical object?
I recently read about precovery, where plates or images of an object predating its discovery are used to precisely determine its orbit. It occurred to me that it might be possible that some objects ...
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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 do HabEx's internal coronagraph and external starshade work together and complement each other? What is it that each can do that the other can't?
Limits of space telescope? links to the video 4 Future Space Telescopes NASA wants to build and that page links to The New Great Observatories. These cover the four space-based instruments proposed by ...
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Identifying cluster of exoplanets between Deneb and Vega
I noticed an interesting patern of exoplanets.
Is this a known phenomenon?
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How do scientists differentiate between a total and a partial transit of a planet passing in front of its star?
Say there's a star in our local neighborhood with a Jupiter-sized planet orbiting around it. This planet's orbit happens to lie approximately in our line-of-sight – we can only see a quarter of it ...
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The electron–cyclotron maser emissions from Earth
The first-ever detection of radio signals caused by the electron–cyclotron maser mechanism outside of the Solar System, on Tau Bootis b was recently published (here). This phenomenon causes huge radio ...
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Minimum distance between planets
In our solar system, MOIDs (minimum orbital intersection distance) of different planets reach a minimum of ~30 million miles (Mercury and Venus). However, other star systems have more compact planets. ...
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Probability of planets in binary star systems?
There is much fiction on binary stars with planets, for whatever reason, and this keeps supporting the popular impression that those systems are frequent. Indeed, the methods for identifying ...
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Simulating oceans and ice sheets on other planets or moons?
From my friends in geosciences I learned a lot about General Circulation Models (GCMs) (for Earth's atmosphere and oceans). I also learned about ice sheet models for floating ice (like sea ice or ...
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What would be the year length of a habitable planet of 40 Eridani A?
The planet Vulcan, in Star Trek, is one of the most famous fictional planets.
The length of a Vulcan year comes up in my answer at:
How old was Spock in Star Trek while he was serving on the ...
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Are planet-destroying quakes possible or observable?
The Gutenberg-Richter-Law is a very-well studied relationship between the magnitude and total number of (earth)quakes. In theory, there is no upper bound for the size of a quake other than the size of ...
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Would the electron cyclotron-maser emission mechanism affect Proxima b's ability to retain an atmosphere?
In a recent arXiv preprint, Pérez-Torres et al. "Monitoring the radio emission of Proxima Centauri" claim the detection of radio emissions synchronised with the orbit of the planet Proxima b....
user24157
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Does a continuous deformable mirror cause diffuse reflection?
We have all seen images like this of deformable mirrors:
Continuous deformable mirrors are known to have a higher quality over segmented mirrors, but it seems to me that a continuous mirror (or even ...
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Are falling evaporating bodies (FEBs) and exocomets the same thing? How does one know they're falling and evaporating?
Looking for a (short) list of comets with heliocentric escape velocity I stumbled upon Wikipedia's exocoments which like exoplanets, are bound to other stars. I should have been looking for "...
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Are stars near the ecliptic the only stars from which Earth would appear to transit the Sun?
The majority of exoplanets we have discovered have been found by the transit method, in which a planet passes in front of its parent star and by analyzing the light curve we can deduct its ...
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Why 2014-2015-2016 were the years when the number of discovered exoplanets increased the most?
So, if we look into the cumulative number of exoplanets discovered by year, you can appreciate a huge rise in the number of discovered exoplanets in the years 2014 and 2016:
Credit to NASA Exoplanet ...
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Why do some pulsar planets have designations with a capital letter at the end?
The pulsar PSR B1257+12 has three planets. Most triple-planet system have designation foo b, foo c, and foo d. However, I noticed that the three planets of this pulsar (PSR B1257+12) have a ...
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Help understanding why these two sub-Hill sphere moon stability limits are so different?
Comments under this answer to What orbital period would produce one New Moon (and one Full Moon) each year? What other effects would this produce? link to
Stable satellites around extrasolar giant ...
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Radial velocity exoplanet search - can mathematical details be explained? (Bayesian periodogram MCMC)
Radial velocity (RV) is one of main methods for exoplanet search.
The popular description of the method sounds simple - one should measure periodic Doppler variation of a spectral line of a star and ...
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Is there a public record of planetary disks apart from ours?
Our planetary disk is not aligned with the rest of the galaxy. Are there publicly available records of the orientations of any other planetary disks?
Especially interested in nearby stars - but I'd ...
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Do celestial objects need to be big to have liquid water on their surfaces?
I mean no asteroid, planetoid that I am aware of has water on its surface. It is way more common to see ice in it. So I figured that the size of the celestial body has something to do with the cycle ...
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Can the Sudarsky's gas giant classification be applied to ice giants?
Based on the temperature of a gas giant around another star, I have come to understand that it is possible to guestimate its appearance; a classification scheme for gas giants developed by David ...
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Technique for folding sparse event data in order to detect an underlying periodicity?
@JamesK's answer to When will the next transit of Earth be visible from Mars? Was the last one really on May 11, 1984? lists dates of 18 transits which I've converted to days since 1500-Jan-01 as
<...
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Calculate mass of exoplanet from transit method
Is there any way to calculate (or at least estimate) mass of an exoplanet from transit method? I know that mass can be calculated with radial velocity method, however I would like to create program ...
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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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What's the big deal with WD 1856+534 b?
A few days ago (september 2020) a planet candidate was announced orbiting white dwarf WD 1856+534. Some media outlets announce it as the First Possible ‘Survivor’ Planet around a white dwarf, while ...
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I have seen so many articles but how can finding exoplanet density determine composition
I have seen some articles and lectures that state but i cant seem to put my finger on on how does density affect composition and how are you able to determine composition from exoplanet density.
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What exactly is a fortney grid transmission spectra modeling
I am trying to model some exoplanets and I don't understand how this model works. Below is a link of the model. What I don’t understand is how does graphing the transit depth vs wavelength provide ...
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Can concentration of gas in exoplanet atmosphere be found out from wavelength and absorbing radius from spectral data?
I was working on exoplanet spectral data from which I need to infer the concentration of gases. However, the exoplanet spectroscopy data contains only absorption wavelength and absorption radius. Is ...
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What do the words "p-type" and "s-type" mean?
As explained in various sources (such as that answer), a planet in an s-type orbit orbits one of the stars of a binary star system, whereas a planet in a p-type orbit orbits both stars. A synonym for ...
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How to recognize exoplanet transit
I am using Python package lightkurve for exoplanets searching by the transit method. When I download light curve of some star and apply periodogram, I find frequency and power of periodic components ...
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Planetary system orientation & the search for exoplanets
A quick review of photographs of galaxies will reveal that not all galaxies are orientated in the same plane as the field of view from Earth. Some galaxies are parallel to our field of view and we see ...
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Where did the idea that tidally-locked planets have a big hurricane come from?
I've been noticing a bit of a trend in the depiction of tidally-locked habitable planets, where they are shown having a huge hurricane-like storm over the daylight hemisphere. Here's an example, and ...
user24157
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What name was voted for Tau Boötis b by the Name Exoworlds Project?
In 2015, the exoplanet Tau Boötis b was included in the Name Exoworlds Project, a project where various international astronomy organizations would propose names for a selection of known exoplanets ...
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How Can I interpret this particular light curve without reading data on the side
There is only one dip in flux recorded. How can I interpret this particular light curve and find planetary radius
https://exo.mast.stsci.edu/exomast_planet.html?planet=55Cnce
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How can I find the radius of a exoplanet using doppler spectroscopy [closed]
I have the stellar and planet mass, planet velocity, radial velocity of star, stellar semimajor axis.
How should I go about to find the radius of this exoplanet?
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Are there ways to determine a star's spectral type without the spectrum itself?
Because of the lack of available data online, I am trying to find other ways to determine an exoplanet's host star's spectral type.
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Does anyone have spectra on exoplanet HD 219134b? How could one know either way?
I have foraged through the internet to no avail.
Is there a way to systematically check if spectra from a given exoplanet has been reported, like a catalog or list of references, or is a literature ...
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