Planet Hunting 101: A Cosmic Game of Hide and Seek (Magratheans Need Not Apply)

1. How do we go about searching for other planetary systems? Or, How to Stalk Planets Like a Pro!

Ah, the hunt for exoplanets! It’s like a cosmic game of “Where’s Waldo,” but instead of finding a guy in a striped shirt, we’re looking for entire planets. And let’s not forget the Magratheans, who are probably chuckling at our efforts. “Searching for planets? Why not just build your own, darling?” they’d say.

Methods to Make Magratheans Jealous:

• Transit Method: This is the “Peekaboo” of astronomy. We watch a star until a planet photobombs it, causing a tiny dip in brightness. It’s like when someone walks in front of the TV while you’re watching your favorite show, except in this case, it’s super exciting and not annoying at all!
• Radial Velocity Method: This is the cosmic tango. A planet and star dance around their common center of mass. If the star starts to wobble, you know it’s not just drunk; it’s got a planetary partner pulling it to and fro.
• Microlensing Method: This is the “Did you see that? No? Nevermind” method. A planet passes in front of a distant star and bends its light. It’s like the universe’s version of bending a spoon with your mind, only way cooler.
• Direct Imaging: This is the paparazzi method. We try to snap a pic of the planet itself, hoping it’s not hiding behind its star’s glare or wearing a cosmic disguise. “Say cheese, Exoplanet!”

Honorable Mentions:

Astrometry, timing variations, polarimetry, interferometry, and spectroscopy. These are like the Swiss Army knife of planet hunting—each tool has its own special use, and they’re all a bit hard to pronounce.

2. Satellites: The Paparazzi of the Cosmos

Kepler: The OG planet hunter. It stared at one patch of sky for four years and found thousands of exoplanets. It’s like that creepy neighbour who knows everything about everyone but in a good way.

Launched in 2009 by NASA, Kepler was a space telescope that used the transit method to survey more than 150,000 stars in a fixed patch of sky for four years. It discovered over 2,600 confirmed exoplanets and thousands more candidates, many of them in the habitable zone of their stars. Kepler also observed stellar activity, supernovae, asteroids, comets, and other phenomena. Kepler’s primary mission ended in 2013 due to a failure in its reaction wheels, but it continued to operate in a reduced mode as K2 until 2018, observing different fields along the ecliptic plane.

TESS: The new kid on the block. It’s like the social butterfly of telescopes, scanning almost the entire sky and making friends with all sorts of celestial bodies.

Launched in 2018 by NASA, TESS is a space telescope that uses the transit method to survey almost the entire sky for two years. It focuses on bright and nearby stars that are ideal for follow-up observations by other instruments. It aims to find at least 50 Earth-sized planets and hundreds of super-Earths in the habitable zone of their stars. TESS also observes stellar activity, supernovae, asteroids, comets, and other phenomena.

JWST (James Webb Space Telescope): The Sherlock Holmes of space. It’s got a big mirror and a knack for solving cosmic mysteries. It can even tell you what an exoplanet had for breakfast by analyzing its atmosphere. No joke!

The James Webb Space Telescope (JWST) is a powerful space observatory that operates in the infrared range of the electromagnetic spectrum. It has a primary mirror of 6.5 meters in diameter and four scientific instruments that can perform various types of observations, including imaging, spectroscopy, and interferometry. One of the main goals of JWST is to detect and characterize exoplanets, the planets that orbit stars other than our Sun. JWST can use different methods to study exoplanets.

CHEOPS, PLATO, ARIEL: The up-and-comers. They’re like the interns of the exoplanet world, eager to prove themselves with fresh data and snazzy new methods.

• CHEOPS: Launched in 2019 by ESA, CHEOPS is a space telescope that uses the transit method to observe known exoplanets and measure their sizes with high precision. It focuses on planets that are in the range of 0.5 to 10 Earth masses, which are of particular interest for understanding their formation and evolution. It also searches for additional planets in the same systems and monitors their transit timing variations.
• PLATO: Scheduled to launch in 2026 by ESA, PLATO is a space telescope that will use the transit method to survey more than 200,000 bright and nearby stars for six years. It aims to find and characterize thousands of exoplanets, especially Earth-like planets in the habitable zone of their stars. It will also measure the seismic activity of the host stars, which can provide information about their age, mass, and radius.
• ARIEL: Scheduled to launch in 2029 by ESA, ARIEL is a space telescope that will use spectroscopy to observe the atmospheres of about 1,000 known exoplanets. It will measure the chemical composition, temperature, and cloud coverage of the planets, which can reveal clues about their origin and evolution. It will also study the diversity and commonality of exoplanet atmospheres across different types of stars and planets.

3. The Exoplanet Census: Or, How Many Planets Does It Take to Screw in a Lightbulb?

As of August 24, 2023, we’ve discovered 5,502 exoplanets. That’s more than the number of times you’ve lost your keys! These planets are as diverse as a bag of jelly beans, with flavours ranging from “Molten Lava” to “Frozen Wasteland.”

The NASA Exoplanet Archive is a reliable and updated database that provides detailed information about each exoplanet and its host star.

Fun Facts:

• Some planets have rings, moons, and even oceans. Magratheans would call these “deluxe features.”
• A few orbit around weird stars like white dwarfs and pulsars. These are the hipsters of the exoplanet world, always trying to be different.
• Some are in the habitable zone, also known as the “Goldilocks Zone.” Not too hot, not too cold, and just right for a cup of tea—or perhaps, life itself!

So, there you have it! Our quest to find exoplanets is like a cosmic treasure hunt, and who knows, maybe one day we’ll find a planet with a “Made by Magrathea” label on it!

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13. How many exoplanets have been discovered? https://spaceexplored.com/2023/08/22/how-many-exoplanets-are-there-discovered/.
14. NASA’s Webb Detects Carbon Dioxide in Exoplanet Atmosphere. https://www.nasa.gov/feature/goddard/2022/nasa-s-webb-detects-carbon-dioxide-in-exoplanet-atmosphere/.
15. NASA’s Webb Reveals an Exoplanet Atmosphere as Never Seen Before. https://www.nasa.gov/feature/goddard/2022/nasa-s-webb-reveals-an-exoplanet-atmosphere-as-never-seen-before/.
16. James Webb Space Telescope reveals alien planet’s atmosphere …. https://www.space.com/james-webb-space-telescope-details-exoplanet-atmosphere.
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18. Peer-Reviewed Paper of JWST Spectrum Reveals First Detection of Carbon …. https://www.lpi.usra.edu/planetary_news/2022/10/25/peer-reviewed-paper-of-jwst-spectrum-reveals-first-detection-of-carbon-dioxide-in-an-exoplanet-atmosphere/.