In April 2018, NASA propelled the Transiting Exoplanet Survey Satellite (TESS). Its fundamental objective is to find Earth-sized planets and bigger “super-Earths” revolving nearby stars for further examinations.
A standout amongst the greatest instruments that will look at the atmosphere of a few planets that TESS finds will be NASA’s James Webb Space Telescope. Since watching little exoplanets with thin atmospheres like Earth will be challenging for Webb, astronomers will target easier, gas giant exoplanets first.
Jacob Bean of the University of Chicago, a co-principal investigator on the transiting exoplanet project said, “We have two main goals. The first is to get transiting exoplanet datasets from Webb to the astronomical community as soon as possible. The second is to do some great science so that astronomers and the public can see how powerful this observatory is.”
Natalie Batalha of NASA Ames Research Center, the project’s principal investigator said, “Our team’s goal is to provide critical knowledge and insights to the astronomical community that will help to catalyze exoplanet research and make the best use of Webb in the limited time we have available.”
Some of Webb’s first observations of gas giant exoplanets will be conducted through the Director’s Discretionary Early Release Science program. The transiting exoplanet project team at Webb’s science operations center is planning to conduct three different types of observations that will provide both new scientific knowledge and a better understanding of the performance of Webb’s science instruments.
At the point when a planet crosses before or travels, its host star, the star’s light is separated through the planet’s atmosphere. Molecules inside the climate retain certain wavelengths, or hues, of light. By part the star’s light into a rainbow range, astronomers can distinguish those segments of missing light and figure out what particles are in the planet’s climate.
For these observations, the scientists selected WASP-79b, a Jupiter-sized planet situated around 780 light-years from Earth. The group hopes to recognize and measure the plenitudes of water, carbon monoxide, and carbon dioxide in WASP-79b. It is expected that the Webb may additionally identify new atoms not yet observed in exoplanet environments.
Phase curve – A weather map
Planets that circle near their stars are more likely to end up being tidally locked. One side of the planet for all time faces the star while the opposite side faces away, similarly as one side of the Moon dependably faces the Earth.
At the point when the planet is in front of the star, we see its cooler rear. In any case, as it orbits the star, increasingly of the hot day-side comes into seeing.
Observing this whole circle, astronomers can watch those varieties (called a stage bend) and utilize the information to delineate planet’s temperature, mists, and science as an element of longitude.
Specifically, scientists will observe the phase curve of the “hot Jupiter” known as WASP-43b, which orbits its star in less than 20 hours. By looking at different wavelengths of light, they can sample the atmosphere to different depths and obtain a more complete picture of its structure.
Bean said, “We have already seen dramatic and unexpected variations for this planet with Hubble and Spitzer. With Webb, we will reveal these variations in significantly greater detail to understand the physical processes that are responsible.”
But the main challenge while observing an exoplanet is to face the star’s light. star’s light is much brighter, swamping the faint light of the planet.
For this, astronomers observed a transiting planet when it disappears behind the star, not when it crosses in front of the star.
By comparing the two measurements, one taken when both star and planet are visible, and the other when only the star is in view, astronomers can calculate how much light is coming from the planet alone.
This technique works best for very hot planets that glow brightly in infrared light. The team plans to study WASP-18b, a planet that is baked to a temperature of almost 4,800 degrees Fahrenheit (2,900 K). Among other questions, they hope to determine whether the planet’s stratosphere exists due to the presence of titanium oxide, vanadium oxide, or some other molecule.
Kevin Stevenson of the Space Telescope Science Institute, a co-principal investigator on the project said, “TESS should locate more than a dozen planets orbiting in the habitable zones of red dwarfs, a few of which might actually be habitable. We want to learn whether those planets have atmospheres and Webb will be the one to tell us. The results will go a long way towards answering the question of whether conditions favorable to life are common in our galaxy.”
Scientists also want to use the Webb to study potentially habitable planets, particularly planets orbiting red dwarf stars.