NASA’s Transiting Exoplanet Exploration Satellite (TESS) has discovered 74 exoplanets, or worlds, outside our solar system. Astronomers are looking for about 1,200 additional exoplanet candidates and potential new worlds await confirmation. More than 600 such candidates are in the northern sky. It is his map that TESS makes.
TESS locates planets while simultaneously observing many stars across large areas of the sky and observing tiny changes in their brightness. When a planet passes in front of its star from our perspective, it blocks some of the star’s light, causing it to temporarily dim. This is called transit, and this process is repeated for each planet’s orbit around the star. This method has proven to be the most successful strategy for finding planets to date. It accounts for about three-quarters of the nearly 4,300 currently known exoplanets. The data collected also allows other phenomena to be studied in unprecedented detail, such as stellar variations and supernova explosions.
The northern panorama is now only a fraction of the data returned by TESS. The mission splits each celestial hemisphere into 13 sectors. TESS filmed each sector for nearly a month using four cameras with a total of 16 sensors – charge-coupled devices (CCDs). During the main mission, the cameras captured a full sector of the sky every 30 minutes. This means that each CCD produces about 30,800 complete scientific images. In addition to other measurements, TESS has transferred over 40TB of data to date, which is the equivalent of streaming about 12,000 HD movies.
It is noteworthy that next year these numbers will rise sharply. TESS has embarked on an extended mission in which he will spend another year filming the southern sky. The satellite will revisit planets discovered in its first year of existence, find new ones, and fill in the coverage gaps found in its initial exploration. Improvements in satellite data collection and processing now allow TESS to return full sector images every 10 minutes and measure the brightness of thousands of stars every 20 seconds.
“These changes promise to make the expanded TESS mission even more rewarding,” explains Padi Boyd, mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Performing high-precision measurements of stellar brightness at these frequencies makes TESS an unusually new resource for studying flaring and pulsating stars and other transient phenomena, as well as for studying the science of transiting exoplanets.”