# Questions tagged [kepler]

Questions about the NASA space observatory famous for finding potentially habitable exoplanets. Do not use this tag for questions about Johannes Kepler.

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### Where can I find online-available datasets for the KIC 8462852?

The question has been asked here seven years ago but unfortunately did not receive an answer perhaps because at that time it would be reasonable to assume that no available dataset might have made it ...
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### Calculate eccentric anomaly using Kepler's equation

I'm developing a C++ computer library with the formulas in the book "Practical Astronomy with your Calculator or Spreadsheet 4th Edition" but I have a problem with the formula 56, "...
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### How does NASA figure out orbital period and mass data for planets and other celestial bodies?

Does NASA calculate orbital periods using Kepler's Laws, or do they measure and observe it in some way? If the latter, how do they do so? Similarly, does NASA calculate the mass of bodies using Kepler'...
1 vote
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### Which factor most affects the accuracy of Kepler's Third Law?

We know that Kepler's 3rd Law is not perfectly accurate due to gravitational perturbations of other planets, moons, etc., but which factors most affect the accuracy? Is it the semi-major axis, mass of ...
1 vote
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### Orbital mean motion expression derivation

I'm reading an article about tidal forces, and the expression for the mean motion is given by: $$n = \sqrt{ \frac{G(M + M^*)}{a^3}}$$ Where $G$ is the gravitational constant, $M$ is the mass of the ...
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### Whether the comet is moving in an elliptical or hyperbolic orbit around the sun?

The time of observation after the first observation (in years), the distance between the earth and the comet (in AU) and the angle between the sun and the comet (in radians) is given. How to find ...
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### Plotting The Kepler Field Full View

I have downloaded the calibrated ffi(full field image) for the Kepler field, aside from the primary HDU which contains the metadata, they contain 84 channels, each in the form of an image HDU, ...
1 vote
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### How to track orbit of an exoplanet?

I was wondering if there is an established method to keep track of the orbit of an exoplanet assuming we know a - the semi-major axis of the orbit, e - the eccentricity of the orbit, and i - the ...
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### Vector analysis of Kepler's Third Law

I want to prove Kepler's Third Law via Vector Analysis of motion. I know of other derivations, but want to know this as I think it will be interesting. I have been unable to prove it. But I know of ...
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### Kepler's Law, focal points - Heliocentric or Barycentric?

It is known that all the mass in the Solar system moves around the Barycenter. For the two focal points in Kepler's law; is the first focal point $F_1$ a Heliocenter? Or is it actually a Barycenter? ...
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### "Periapsis" or "Periastron"?

I was taught from Bate Mueller and White, that the proper terms for the closest and furthest points and distances from a body in orbit around another unspecified body are "periapsis" and &...
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### Data to "check" Kepler’s first law

I want to "check" Kepler’s first law by using real data of Mars. From the equation of the ellipse, I derived $$\frac{1}{r}=\frac{a}{b^2}+\frac{a}{b^2}\cdot\epsilon\cdot\cos(\varphi),$$ where ...
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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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### How to find the mass of a planet not knowing the gravitational constant?

So I found this problem, I know the gravity of earth $g_0$, I found the orbital speed of one satellite using this equation $\frac{GM_em_s}{(R_e+h)^2}=m_sa$ ($M_e$ is the mass of earth, $m_s$ is the ...
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### How did Kepler come to the potencies in his Third Law?

How did Kepler come to the conclusion, that exactly the square of the period and the third potency of the great semi-axis of the ellipse is proportional? Why is only square divided by cubic = ...
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### Keplerian Elements for the Moon and Earth around their Barycenter

So I'm looking to replicate the inner Solar System to a decent degree of accuracy. So far I've been utilizing the Keplerian Elements and Equations for the planets, as shown here. There is one issue ...
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### Keplerian Elements for Approximate Positions of the Major Planets

Simple question here. I am working on something that needs to compute an orbital path using Keplerian Elements. When doing some research I came across this JPL page: Click Here. Within that link is a ...
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### Pair together light curve and radial velocity data of specified star

I would like to create a web application that works with light curves and radial velocities of stars with exoplanets. I found a NASA bulk data download with both light curves and radial velocities (it'...
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### How was Kepler's field of view chosen? [duplicate]

The Kepler space telescope points to a single place in the sky, and a quarter of a percent of the sky. How was this field of view chosen? Why did the Kepler team choose to point the telescope there ...
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1 vote
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I search for lightcurve Kepler data: time $t_i$, flux $F_i$ and measurement uncertainties $\sigma_i$ I need processed data (after removing trends, normalized, etc.). Where can I find it?
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### Are gas giants actually rare?

Kepler data suggests that the vast majority of planets are smaller than 4 Earth radii, with larger planets quickly becoming vanishingly scarce. Yet somehow, our own solar system harbours not just one, ...
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### Kepler space telescope undetected planets

The Kepler space telescope detects planets based on the dip in brightness caused by planets moving past the star. Wouldn’t that mean that there are an unknown amount of planets that have an orbit ...
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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 ...
1 vote
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### Mass of a potential black hole in a binary system

So I've been given the velocity curve, parallax and apparent magnitude of a star in a binary system with what is potentially a black hole. I've calculated from the apparent magnitude and parallax that ...
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### nonagesimal in Kepler's parallax computation

I'm starting to learn Kepler's Astronomia Nova using William Donahue's translation . In the translator's introduction, it is demonstrated how Kepler did his parallax computation. I failed to ...
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### What happened to the third planet in the Kepler-47 system?

In 2012, the discovery paper for the multiplanet circumbinary system Kepler-47 mentioned a potential third transiting planet in the system: A 0.2% deep transit-like event is present at time 2,455,...
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### keplers third law

does Keplers third law work if one were to, in some way use the semi minor axis instead of the semi major axis? and does the difference between the arithmetic, geometric and harmonic means play any ...
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### Just how "locked" are resonant-chains of exoplanets thought to be? (e.g. K2-138 and TOI-178)

update 2: A&A: Six transiting planets and a chain of Laplace resonances in TOI-178 (and arXiv) Gizmodo: Enigmatic Star System Has 5 Planets Locked in Perfect Harmony Bad Astronomy A Six-Planet ...
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### Can one approximate the semi-major axis of an orbit as the average orbital distance for eccentric orbits?

Kepler's 3rd Law (regarding the relation between orbital period and the semi-major axis of an orbit) applies to all elliptical orbits. But as I understand it, the only reason it is safe to use the ...
1 vote
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### Where can I find detail on interpreting the exo-planet transit-data graphics used in the Zooniverse Project?

I'm participating in the Zooniverse Exoplanet-explorers project (transit method), which provides only minimal guidance on interpreting their light curve and transit data graphics, as visible here: ...
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### Mean and true Sun

I have problems to understand the point of "mean sun" and "true sun". As I understood the mean sun is set in the center of the earth orbit (which is a circle). So Ptolemy, Copernicus and Brahe used ...
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### What caused instant jumps and exactly flat periods in Kepler's light curves?

Last 65 days of Kepler's light curve for the infamous KIC 8462852 star is shown below from the published paper's graph. Skip the dips here, I wonder about two other features: Day 1559, during a ...
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### What complementary observation campaigns have looked at Kepler's field of view?

It seems to be common practice to double up observations. For example, shortly before New Horizons flew by Pluto, several of its moons were discovered by telescopes as a concerted effort was put in ...
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### Has star KIC 8462852's 3 year long Kepler-fading continued after the primary Kepler mission ended?

BACKGROUND May 11, 2013 the Kepler space telescope ended its primary mission. Data captured until then showed that the now famous "Tabby's star" or "Boyajian's star" (KIC 8462852) had been fading ...
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### Getting light curves from Kepler/K2

Hello I'd like to ask what are steps to get a light curve wfrom Kepler/K2 database. Let's say I'd need to get light curves of 10 random K type stars. How should I access the databases and what should ...
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### According to my calculations Jupiter's moons do not follow Kepler's 3rd law - Why is that?

I'm asked to collect data on the orbital properties of the four Galilean satellites of Jupiter and show that they obey the same scaling as in Kepler's 3rd law. My approach for moon Io: Online, I ...
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### Why does Kepler's "Big Picture" of comet 67P look so strange? And what is the significance?

The observation of comet 67P by the Kepler space telescope has been reported in various science news outlets recently. For example, the image below appeared in the recent NASA news article NASA's ...
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### Hot and "warm" Jupiters expelling terrestrial planets?

I've seen in documentaries that if a Jupiter size planet migrates close to its star then it would remove terrestrial planets along the way. This makes sense and I'm sure most models would predict this,...
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### What does "forward facing" mean for space telescopes?

I just noticed this announcement from the K2 mission that the field observed for Campaign 16 of the K2 mission would be changed so that the telescope would be "forward facing", saying that "observing ...
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### How to find out which Messier objects are in the Kepler/K2 fields?

I am interested in figuring out which Messier globular clusters (plus 47 Tuc and Omega Cen) are in the Kepler/K2 fields, both fields that have already been observed and any that will be observed. ...
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### What telescopes have observed anomalies in the light curve of Tabby's star, KIC 8462852?

KIC 8462852, the F-star that inexplicably dims by up to 20% for short periods, is still getting alot of attention. A slow continuous dimming by about 0.3% a year has been identified recently. But all ...
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### Kepler's second law of motion

Planets sweeps out equal areas in equal times. Is the area being calculated here the area of a triangle? You draw a straight line from the center of the sun to the earth at point A. The Earth moves ...
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### Likelihood of extra planets in systems identified by Kepler?

Kepler has found some systems with multiple planets and shown that it's likely that 7% of sun-like stars have Earth-like planets (video). I don't think we know enough about extra solar planets to ...
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### Has the Kepler data been examined for light curves due to phase changes of non-transitting hot Jupiters and other?

I found this article http://www.epj-conferences.org/articles/epjconf/pdf/2011/01/epjconf_ohp2010_03005.pdf from 2011 announcing that two dozen secondary eclipses of "hot Jupters" have been seen in ...
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### My question relates to KIC 8462852. What are the orbits and suspected objects or planets that have been noted around this star? [closed]

What are the orbits and suspected objects or planets that have been noted around this star? KIC 8462852
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### How does gyrochronology deal with differential rotation and axial tilt?

K2 seems to become an even better mission than what a continuation of Kepler would have been, at least to some astronomers. By what means is differential star rotation being dealt with? The rotational ...
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### Correlation of planet sizes with star sizes?

I did my own amateur Kepler data analysis in May of this year of data from Kepler.nasa.gov/Mission/ discoveries. I found a strong correlation between star size and planet size (percentages). 37 of the ...
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### Classification of Planets?

The data from Kepler has taught us that there is a much larger number of "Neptune-class" planets out there than we previously thought. I wonder, however, if this "dominance" of Neptunes is because of ...
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### Reason for a correlation between Hot Jupiters and higher metallicity in Kepler data

This question is from an amateur data analysis I did in May 2015 of data from Kepler.nasa.gov/Mission/discoveries. There were 80 Jupiter size planets in the Kepler "confirmed" planet table ...
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