An exoplanet, or extrasolar planet, is a planet orbiting a star outside our solar system. The first confirmation of detection of one came in 1992, with discovery of two planets orbiting pulsar PSR B1257+12 (2.300 light-years away. in the constellation of Virgo). A third planet was found there in 1994. The count of confirmed exoplanets has ticked past 5,000- the culmination of 30 years of exploration, led by NASA space telescopes such as Kepler.
The 5,000+ planets found so far include small, rocky worlds like Earth and gas giants many times larger than Jupiter.
Oddities not seen in our solar system include:
• “Hot Jupiters”- Gas giants in scorchingly close orbits around their stars.
• “Super-Earths” – Possible rocky worlds bigger than our own.
• “Mini-Neptunes” – Smaller versions of our own Neptune.
• Planets orbiting two stars at once (like Tatooine in Star Wars).
• Planets orbiting the collapsed remnants of dead stars.
NASA estimates our galaxy holds hundreds of billions of strange and wonderful planets, and that someday we may find a habitable one… or one that is already inhabited.
Exoplanets form directly from larger structures in the primordial disks of gas and dust orbiting young stars. Hubble became the first telescope to directly detect an exoplanet’s atmosphere and survey its makeup. As a planet passes between its star and us, a small amount of light from the star is absorbed by the gas in the planet’s atmosphere, leaving chemical “fingerprints” in the star’s light.
Picture Credit: Google
