6

There are two separate points of interest you're looking at so I'll separate this into sections. Sudden Drop at Day 1559 As near as I can tell, this is the result of a quarterly roll of the satellite, specifically the end of quarter 17. Every 90 days, which NASA calls a quarter, the space craft does a 90 degree roll to optimize the solar panel efficiency. ...


5

The second light curve you show has no obvious periodic behaviour and I cannot see any sign of a planetary transit. The period-finding algorithm appears to be working correctly. The planet (if it exists) is supposed to be one of the smallest planetary candidates found by Kepler and will have a barely detectable transit (depth of order 0.004%). The small ...


4

To calculate a "luminosity light curve" from a time series of V-band photoetry, you need two things. You need to know the distance. The distance to Betelgeuse is uncertain and that means the absolute value of the luminosity you get will also be shifted systematically up or down by whatever distance you adopt. The V-band only contains a small ...


4

Cepheid variable stars and exoplanets transiting stars have very different light curves (the relation between brightness and time). Exoplanet light curve from NASA: Cepheid variable light curve from astronomynotes.com: Also, as Rory Allsop points out, the scale of the change in brightness is very different. Cepheid variables can be seen at great distances,...


4

I think this scenario is unlikely. There is no evidence Tabby's star is near a neutron star. Astronomers are monitoring Tabby's star very closely and there has not been any detection of the radio emission, gamma rays, or x-rays you would expect to see from a neutron star. Also something as heavy as a nearby neutron star would have a lot of gravity ...


3

Not sure what you are expecting to see from the two datasets. Both datasets are examples of light curves, flux against time with different arbitrary origins for the time axis; SuperWASP TMID is integer seconds from Julian Date 2453005.5, Kepler uses BKJD = Barycentric Kepler Julian Date, but offset by 2454833.0. i.e., BKJD = BJD - 2454833.0. The SuperWASP ...


3

What you are looking for is here. http://archive.stsci.edu/kepler/search_retrieve.html This one is good for exoplanet light-curves https://exo.mast.stsci.edu/


3

I think you may be seeing the planet in the periodogram! But also another signal - higher harmonics of other periodic signals example - various periodic signals in our sun - with a characteristic period of 11 years (in the bottom panel you also see Earth's, as this is a local measure, and thus is mostly affected by our distance from the sun) Patterns of ...


2

Calculation of both, depth and duration, is usually done not on the raw data but derived from a fit to the data. In your last three lines of code you also calculate the average / medium over all data while you should calculate the uneclipsed mean or median flux only for the non-transit time (with using median it possibly has only a tiny influence, yet it ...


1

Of course you will get multiple peaks in the periodogram. The Fourier series representing a non-sinusoidal signal will contain frequencies at multiples of the fundamental frequency. Similarly, you can have a periodic signal with double or treble the period which will look identical, but where the phenomenon causing the signal repeats either two or three ...


1

Nickel 56 decays to Cobalt 56 via electron capture decay, with a half-life of 6.1 days and a decay constant of $\lambda = 1.31\times 10^{-6}$ s$^{-1}$. About 1.75 MeV of energy is lost as gamma rays and a further 0.41 MeV in the form of an electron neutrino (Nadyozhin 1994) Let's assume that we are talking about the period of time after the initial ...


1

The radius of the planet is 0.17% of Jupiter's radius. Under the "Planet" info on the left, it says $R_P$ which is the radius of planet, and since the units are shown as $[R_J]$ this is the value is in comparison to Jupiter. It also gives the $M_P$ (mass of planet) in relation to $M_J$ (mass of Jupiter) as well. The interesting thing here is the ...


1

An excellent page to get most or all names for a star is Simbad which also happens to know the Kepler IDs (KID). Ont the other hand, every of the RV data files contains info on the star's identifier it belongs to in the header, e.g: \STAR_ID='HD 4628' So using Simbad you should be able to do a cross-matching. SimBad allows scripted query and includes ...


1

The file format for submitting observations to AAVSO sheds some light on this. "Visual" data are estimates by visual comparison to nearby reference stars of similar brightness. U, B, V, R, I data come from CCD cameras using standard filters in the Johnson-Cousins photometric system, with passbands ranging from near ultraviolet to near infrared. The J and H ...


1

Following Mick's comment, I found an astropy-function - DAOStarFinder - that does what I was looking for. It scans an image for light-sources and one can set threshhold for a detection, e.g. the "roundness", "sharpness" or brightness of an object have to be between [-0.05,0.05], [0.6,0.8] or >5*standard_deviation, respectively. I must say, that I have the ...


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