Scientists use single-pixel images of Earth to better understand exoplanets

Scientists have been studying exoplanets to learn more about Earth's evolution and whether or not extraterrestrial lives exist. The exoplanets, the planets that are outside our solar system, are, however, very far away from us and it is quite difficult to get an idea of ​​what happens there. So, now, NASA has created a new study that uses our home planet as a substitute for an exoplanet. It shows that even in the presence of very little light (one pixel), it is still possible to evaluate the significant characteristics of distant worlds.

This new study uses data from NASA's Polychromatic Earth Imager. This instrument, EPIC, is on board the satellite of the Deep Space Climate Observatory (DSCOVR) of the National Oceanic and Atmospheric Administration. Travel around the Sun at point 1 of Lagrange, which is a particular orbit that gives EPIC a continuous view of the surface illuminated by the Earth's sun. EPIC has been operational since 2015. It has produced detailed maps of the surface of our home planet in multiple wavelengths and has also contributed greatly to climate and climate studies.

From EPIC captures the image of the Earth's reflective lights in 10 different wavelengths or colors; each time the instrument "takes a photograph" of the Earth, it actually takes 10 images. The new NASA study averages each of the images in a single brightness value, which is the equivalent of a "single pixel" image for each wavelength. This unique image of a pixel on Earth is able to provide very little data on its surface. However, the authors of the document actually examined and studied a data set that contained single-pixel images that were clicked several times a day at 10 wavelengths, over a prolonged period of time.

Researchers were actually able to determine several facts about the planet from those single-pixel images, such as clouds of water in the atmosphere and their rotation speed.

"The benefit of using The Earth as a proxy for an exoplanet is that we can verify our conclusions derived from the data of a single pixel with the large amount of data we have for the Earth, we can not do that if we are using data from a distant exoplanet and real, "said Jonathan Jiang, lead author of the study. that was published in Astrophysical Journal. Jian is also atmospheric and climatic scientist at NASA's Jet Propulsion Laboratory in Pasadena, California.

Currently, Jiang is making use of climate data to achieve further development in exoplanet studies. Now, these exoplanets are much dimmer than stars and are also much harder to detect. For example, Earth is about 10 billion times fainter than the Sun. While scientists have detected more than 3,700 exoplanets to date; only 45 of them were detected through direct images.

The new NASA study shows that if we can observe an exoplanet with discrete characteristics for a long time; it would be possible to evaluate the rotation speed of that planet by monitoring a repetitive pattern in the reflected light. "People have been talking for some time about the use of this approach to measure the rotation speed of exoplanets, but there has not been any proof that it could work because we did not have real data, we have shown that at each wavelength, 24 "The period appears, which means that this approach to measuring the rotation of planets is solid," said exoplanet scientist Renyu Hu of NASS JPL and co-author of the study.

This new study should help scientists understand more about the exoplanets and that they know, soon they will also be able to find us some extraterrestrial neighbors!