In this week, NASA is planning to launch its new exoplanet seeker mission that can look out there at the cosmos hunting for never-before-seen worlds. Transiting Exoplanet Survey Satellite (TESS) spacecraft is assigned with looking for planets around stars apart from our Solar System to help researchers find out exactly what these types of planets are made up of and if any possibility that supports life.
TESS is launching on April 16th, much like NASA’s previous exoplanet seeker is going to hang up its hat. NASA’s Kepler spacecraft launched in 2009, can run out of fuel sometime within the next few months. However, TESS features a diverse objective compared to the earlier model. Kepler’s objective was to discover as many exoplanets as feasible; TESS is going to be pickier, seeking out planets around the closest stars to Earth. These types of planets will be much simpler to analyze as their stars will be brighter, according to NASA.
BRIGHTER IS BETTER
Kepler looked at a few modest areas of the sky during the time, searching for up to 100, 000 stars. TESS will be observing a field of view that’s 400 times even wider. And it will be able to observe approximately 200, 000 stars, possibly millions. “Having TESS in the fold is just fantastic,” Jessie Dotson, an astrophysicist at NASA’s Ames Research Center and the project researcher for the Kepler spacecraft, tells “They’re planning to discover planets in areas of the sky we can’t look at .”
TESS will work with the identical method as Kepler used to discover and analyze planets. It will search for planets since they pass in front of their host stars, in what’s called a transit. While any planet transits, it somewhat dims the light of the parent star enough for an orbiting telescope to measure. However, TESS will focus on much closer stars than Kepler observed. They’ll only be tens to hundreds of light-years away, as opposed to thousands of light-years away, which makes them 30 to 100 times brighter in the sky. That will ensure it is easier for astronomers to find out more about the planets around them.
To understand what a planet is composed of — whether it’s rocky like Earth or a gas giant like Jupiter — you need to understand its density. And the best method to measure density would be to observe how the planet tugs on its host star. Although a planet is comparatively small, it still has a gravitational influence over the star, leading to the celestial object to wobble slightly. The scope of this wobble tells us to how massive a planet is.
Brighter stars make it easier to determine this wobble fairly quickly. With distant and faint stars, astronomers don’t gather much light, so it takes longer to get exactly how the star is shaking. For the types of stars Kepler observed, it may take several weeks or months to find out a star’s wobble and, and as a result, the composition of a nearby exoplanet. However, for the bright stars that TESS will analyze, it could require just a couple of hours.
With Kepler, astronomers were only permitted to measure a few stars, says Rinehart. “With TESS, it’s going to be the opposite problem. It’s going to be ‘I can do any of these targets. Which one do I want to do ?’”