What is an Exoplanet?
Exoplanets are the planets that orbit around other stars located outside our solar system. Exoplanets are also called extrasolar planets. All the stars have atleast 1 planet revolving around them. Most of the exoplanets discovered so far are located in Milky way galaxy.
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Why is it Hard to Detect the Exoplanets Directly with Telescopes?
Exoplanets are hard to be detected directly with telescopes as they are close to the stars they orbit. The brightness of stars prevents it from being detected easily.
How do we Detect Exoplanet?
- Transit method
- Doppler spectroscopy
What is the Transit Method of Exoplanet Detection?
Whenever a planet passes in front of its star, it is called a transit. Whenever a planet transits in front of its star, a small amount of stars light is obstructed. Hence, there will be a reduction in the brightness of the star. Astronomers can detect the change in brightness of the star, which helps them in evaluating the size of the planet. Astronomers are able to detect the distance of the exoplanet from its star by studying the time between transits.
What is Doppler Spectroscopy Method of Exoplanet Detection?
It is an indirect method of Exoplanet detection. This method makes use of periodic shifts in the radial velocity. It analyses the change in the spectrum of the exoplanets parent star. This is also called Wobble method of detection.
Which is the Closest Exoplanet?
The closest exoplanet is named Proxima Centauri b. It is a planet orbiting the closest star to the Sun, named Proxima Centauri.
How Many Exoplanets have been Confirmed?
Approximately 4,000 exoplanets have been confirmed. These exoplanets were found in 3,096 systems. Out of these systems, 678 systems have more than one planet.
Which is the Least Massive Exoplanet?
The least massive known exoplanet is named as Draugr. To get an understanding of its size, this exoplanet is twice the mass of the moon.
Which is the Most Distant Discovered Exoplanet?
It is named as SWEEPS-11/SWEEPS – 04. It is located 27,710 light-years away.
Which is the Hottest Exoplanet Discovered?
The hottest exoplanet discovered is Kepler – 70b
Which is the Biggest Exoplanet Discovered?
The biggest exoplanet discovered is Kepler – 39b.
Multiple Choice Question
Consider the following Statements?
- The brightness of stars prevents it from being detected easily.
- Exoplanets are also called extrasolar planets.
- The closest exoplanet is named Proxima Centauri b.
- Astronomers are able to detect the distance of the exoplanet from its star by studying the time between transits. This method of detection is called Doppler Spectroscopy.
Which of the following Statements are True.
A) 1 alone is true
B) All 4 statements are true
C) Only 1,2 and 3 are true
D) None of the above statements are true.
Exoplanets- UPSC Notes:- Download PDF Here
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