Home Earth and Planetary Shadow Imaging of Transiting Objects

[1812.01618] Shadow Imaging of Transiting Objects


(Submitted on 4 Dec 2018)

Abstract: We consider the problem of inferring the shape of a transiting object’s
silhouette from its light curve alone, without assuming a physical model for
the object. We model the object as a grid of pixels which transits the star;
each pixel has an opacity, ranging from transparent to opaque, which we infer
from the light curve. We explore three interesting degeneracies inherent to
this problem, in which markedly different transiting shapes can produce
identical light curves: (i) the “flip” degeneracy, by which two pixels
transiting at the same impact parameter on opposite sides of the star’s
horizontal midplane generate the same light curve; (ii) the “arc” degeneracy,
by which opacity can be redistributed along the semicircular arc of pixels
which undergoes ingress or egress at the same time without consequence to the
light curve, and (iii) the “stretch” degeneracy, by which a wide shape moving
fast can produce the same light curve as a narrow shape moving more slowly. By
understanding these degeneracies and adopting some additional assumptions, we
are able to numerically recover informative shadow images of transiting
objects, and we explore a number of different algorithmic approaches to this
problem. We apply our methods to real data, including the TRAPPIST-1c,e,f
triple transit and two dips of Boyajian’s Star. We provide Python code to
calculate the transit light curve of any grid and, conversely, infer the image
grid which generates any light curve in a software package accompanying this
paper, EightBitTransit.

Comments:24 pages, 13 figures, accepted to AJ. Accompanying software package available online at this https URL
Subjects:Earth and Planetary Astrophysics (astro-ph.EP)
Cite as:arXiv:1812.01618 [astro-ph.EP]
arXiv:1812.01618v1 [astro-ph.EP]
for this version)

Submission history

From: Emily Sandford [view email]

Tue, 4 Dec 2018 19:00:04 UTC (810 KB)


Source link


Please enter your comment!
Please enter your name here

Enter Captcha Here : *

Reload Image

Must Read

Why everyone is talking about energy storage | MNN

Ever since governments started getting serious about developing renewable energy, naysayers have been arguing that it's a pipe dream — after all, the...

Give charities free ad space on your smartphone’s lock screen with Screen Donor

This app gives free ad space to deserving charities and NGOs on one of our tech-centric culture's most commonly seen screens - our...

Tropicana 100% Juice 3-Flavor Fruit Blend Variety Pack, 10 Fl Oz, Bottles, (Pack of 24)

Price: (as of - Details) Now you can enjoy the refreshing taste of Tropicana’s Fruit Medley, Pineapple Peach Mango and Strawberry Orange Juice...

Cell phones and screens are keeping your kid awake

For children and teens, using cell phones, tablets and computers at night is associated with losing sleep time and sleep quality, new research...