Topics Covered:
- Awareness in space.
Transiting Exoplanet Survey Satellite
What to study?
- For Prelims: TESS- key features.
- For Mains: Scientific objectives and significance of the mission.
Context: Nasa which launched Transiting Exoplanet Survey Satellite (Tess) for searching exoplanets in April, 2018 has discovered a third small planet outside our solar system.
THE NEW PLANET:
The new planet is named HD 21749b. The newly discovered planet orbits a bright and nearby star which is about 53 light years away in the constellation Reticulum. HD 21749b appears to have the longest orbital period of the three planets so far identified by Tess. The surface of the new planet is hotter than 100 degrees Celsius.
About TESS mission:
The Transiting Exoplanet Survey Satellite (TESS) is a NASA mission that will look for planets orbiting the brightest stars in Earth’s sky. It was led by the Massachusetts Institute of Technology with seed funding from Google.
Mission: The mission will monitor at least 200,000 stars for signs of exoplanets, ranging from Earth-sized rocky worlds to huge gas giant planets. TESS, however, will focus on stars that are 30 to 100 times brighter than those Kepler examined. This will help astronomers better understand the structure of solar systems outside of our Earth, and provide insights into how our own solar system formed.
Orbit: TESS will occupy a never-before-used orbit high above Earth. The elliptical orbit, called P/2, is exactly half of the moon’s orbital period; this means that TESS will orbit Earth every 13.7 days. Its closest point to Earth (67,000 miles or 108,000 kilometers) is about triple the distance of geosynchronous orbit, where most communications satellites operate.
How it works? It will use transit method to detect exoplanets. It watches distant stars for small dips in brightness, which can indicate that planet has passed in front of them. Repeated dips will indicate planet passing in front of its star. This data has to be validated by repeated observations and verified by scientists.
Significance of the mission:
- TESS is designed to build on the work of its predecessor, the Kepler space telescope, which discovered the bulk of some 3,700 exoplanets documented during the past 20 years and is running out of fuel.
- Nasa expects to pinpoint thousands more previously unknown worlds, perhaps hundreds of them Earth-sized or “super-Earth” sized – no larger than twice as big as our home planet.
- Those are believed the most likely to feature rocky surfaces or oceans and are thus considered the best candidates for life to evolve. Scientists have said they hope TESS will ultimately help catalog at least 100 more rocky exoplanets for further study in what has become one of astronomy’s newest fields of exploration.
Sources: the hindu.
