MSU SciFest 2021: Exo-lent Planets!

Presented at the virtual MSU Science Festival 2021 on April 10, 2021. Note that gifs and videos won't render in this pdf.

The Sun isn't the only star to have planets orbiting it -- thousands of alien worlds in other solar systems have been found, most of them in the last 10 years. There is a huge diversity in exoplanets types not seen in our own Solar System, like hot Jupiters and super Earths, and we've found a few exoplanets that would probably be habitable! In this talk you'll learn about how these exoplanets are formed, how scientists have discovered them, and why we shouldn't plan to visit one anytime soon.

More information on MSU SciFest: https://sciencefestival.msu.edu/
More information on exoplanets: https://exoplanets.nasa.gov/

Transcript

1. Exo-lent Planets! Dr. Abbie Stevens MSU & UMich Image credit: B. Watterson
2. Dr. Abbie Stevens, MSU Science Festival 2021
3. Tatooine, Star Wars Dr. Abbie Stevens, MSU Science Festival 2021
4. (technically an exomoon…) Pandora, Avatar Dr. Abbie Stevens, MSU Science Festival 2021
5. Krypton, Superman & DC Comics Dr. Abbie Stevens, MSU Science Festival 2021
6. Omicron Persei 8, Futurama Dr. Abbie Stevens, MSU Science Festival 2021
7. Vulcan, Star Trek Dr. Abbie Stevens, MSU Science Festival 2021
8. The Stillness, The Broken Earth trilogy Dr. Abbie Stevens, MSU Science Festival 2021
9. Arrakis, Dune Dr. Abbie Stevens, MSU Science Festival 2021 Image: M. Molnar
10. Sargasso, Ratchet and Clank Dr. Abbie Stevens, MSU Science Festival 2021
11. Miller tidal planet, Interstellar Dr. Abbie Stevens, MSU Science Festival 2021
12. Asgard, Norse myth & Marvel comics Dr. Abbie Stevens, MSU Science Festival 2021
13. Gallifrey, Doctor Who Image: BBC Dr. Abbie Stevens, MSU Science Festival 2021
14. Caprica, Battlestar Galactica Dr. Abbie Stevens, MSU Science Festival 2021
15. What are exoplanets? Dr. Abbie Stevens, MSU Science Festival 2021 planet - something in space that: Image: VectorStock
16. What are exoplanets? Dr. Abbie Stevens, MSU Science Festival 2021 planet - something in space that: (a) orbits around our Sun Image: VectorStock
17. What are exoplanets? Dr. Abbie Stevens, MSU Science Festival 2021 planet - something in space that: (a) orbits around our Sun (b) has enough mass for its own internal gravity to make it into a ball Image: VectorStock
18. What are exoplanets? Dr. Abbie Stevens, MSU Science Festival 2021 planet - something in space that: (a) orbits around our Sun (b) has enough mass for its own internal gravity to make it into a ball (c) is the biggest thing in its orbit Image: VectorStock
19. What are exoplanets? Dr. Abbie Stevens, MSU Science Festival 2021 planet - something in space that: (a) orbits around our Sun (b) has enough mass for its own internal gravity to make it into a ball (c) is the biggest thing in its orbit If only (a): comets, asteroids (a) & (b): moons, dwarf planets Image: VectorStock
20. What are exoplanets? exoplanet – a planet outside our Solar System orbiting its own Sun (its ‘host’ star) planet - something in space that: (a) orbits around our Sun (b) has enough mass for its own internal gravity to make it into a ball (c) is the biggest thing in its orbit Dr. Abbie Stevens, MSU Science Festival 2021
21. Image: ESO/L. Calçada How are exoplanets formed? Protoplanetary disk Dr. Abbie Stevens, MSU Science Festival 2021
22. Image: ESO/L. Calçada How are exoplanets formed? Protoplanetary disk Dr. Abbie Stevens, MSU Science Festival 2021 A real one around the baby star TW Hydrae Image: ALMA/S.Andrews/B.Saxon
23. Dust Dr. Abbie Stevens, MSU Science Festival 2021 How are exoplanets formed?
24. Dust Rocks Dr. Abbie Stevens, MSU Science Festival 2021 How are exoplanets formed?
25. Dust Rocks Planetesimals (~1-5 miles) Dr. Abbie Stevens, MSU Science Festival 2021 How are exoplanets formed?
26. Dust Rocks Planetesimals (~1-5 miles) Dr. Abbie Stevens, MSU Science Festival 2021 How are exoplanets formed? Protoplanets
27. Dust Rocks Planetesimals (~1-5 miles) Planets! Terrestrials Gas giants Ice giants Dr. Abbie Stevens, MSU Science Festival 2021 How are exoplanets formed? Protoplanets
28. Dust Rocks Planetesimals (~1-5 miles) Planets! Terrestrials Gas giants Ice giants Total time: ~100 million years Dr. Abbie Stevens, MSU Science Festival 2021 How are exoplanets formed? Protoplanets
29. Dr. Abbie Stevens, MSU Science Festival 2021 A brief history of exoplanets • 1st theorized by Giordano Bruno, late 1500’s
30. A brief history of exoplanets • 1st theorized by Giordano Bruno, late 1500’s • 1st published discovery in 1988 (withdrawn in 1992, confirmed in 2003) (g cephei Ab by Campbell, Walker & Yang) • 1st confirmation of two rocky planets around a pulsar in 1992 (PSR B1257+12 b,c by Wolszczan & Frail) • 1st confirmation of an exoplanet orbiting a normal Sun-like star in 1995 (51 Pegasi b by Mayor & Queloz) Dr. Abbie Stevens, MSU Science Festival 2021
31. Two most successful methods to date: 1. Radial velocity 2. Transit Dr. Abbie Stevens, MSU Science Festival 2021 How do we discover exoplanets?
32. Radial velocity: GIF: Wikipedia Dr. Abbie Stevens, MSU Science Festival 2021 How do we discover exoplanets? • Star wobbles due to gravity of the exoplanet • Color of light from the star shifts bluer and redder because of this motion, like listening for a siren to get higher then lower • Can help figure out mass of exoplanet
33. Transit: Images: NASA Ames, D. Berry Dr. Abbie Stevens, MSU Science Festival 2021 How do we discover exoplanets? • As the planet passes in front of the host star, it blocks a tiny amount of the star’s light • We can detect this change in brightness with sensitive telescopes • Can help constrain size of the exoplanet
34. Transit: Images: NASA Ames, D. Berry Dr. Abbie Stevens, MSU Science Festival 2021 How do we discover exoplanets? • As the planet passes in front of the host star, it blocks a tiny amount of the star’s light • We can detect this change in brightness with sensitive telescopes • Can help constrain size of the exoplanet
35. CSA, 2003 MOST NASA, 2009 Kepler and K2 CNES/ESA, 2006 CoRoT NASA, 2018 TESS Dr. Abbie Stevens, MSU Science Festival 2021 How do we discover exoplanets?
36. • 4 planet types: gas giant, super-Earth, Neptunian, and terrestrial • 3 temperature zones: hot, warm, cold Dr. Abbie Stevens, MSU Science Festival 2021 Types of exoplanets
37. TrES-2b • Hot Jupiter • About 700 LY away • Draco constellation • Reflects < 1% of incoming light - blacker than coal, air is the temperature of lava Image: D.A.Aguilar/TrES/Kepler/NASA Dr. Abbie Stevens, MSU Science Festival 2021 Real exoplanets!
38. Fomalhaut b § Cold gas giant? § 25 LY away § Surrounded by dust and debris § No near-infrared emission found Image: HST/NASA/P.Kalas Dr. Abbie Stevens, MSU Science Festival 2021 Real exoplanets!
39. Teegarden b and c • Warm terrestrials • 12 LY away • Aries constellation • Orbiting an evolved red dwarf star (lots of flares) Image: PHL at UPR Arecibo Dr. Abbie Stevens, MSU Science Festival 2021 Real exoplanets!
40. Tatooine types! (circumbinary planets) • Kepler 16b 200 LY away, gassy, Cygnus constellation • Kepler 34b • Kepler 35b • Kepler 38b • Kepler 47b, c Image: ESO Dr. Abbie Stevens, MSU Science Festival 2021 Real exoplanets!
41. J1407b • 40x Jupiter mass • 434 LY away • Has ring system 200x the diameter of Saturn’s rings (contain approx. an Earth’s mass of dust particles) Dr. Abbie Stevens, MSU Science Festival 2021 Real exoplanets! Image: Ron Miller
42. J1407b • 40x Jupiter mass • 434 LY away • Has ring system 200x the diameter of Saturn’s rings (contain approx. an Earth’s mass of dust particles) Dr. Abbie Stevens, MSU Science Festival 2021 Real exoplanets! Image: Ron Miller, Matt Kenworthy If it were at Saturn, we’d be able to see the rings!!!
43. Kepler 7b • Hot Jupiter • As dense as Styrofoam • Same side of planet always faces the star • First exoplanet to have its clouds mapped! Dr. Abbie Stevens, MSU Science Festival 2021 Real exoplanets! Image: NASA/JPL-Caltech/MIT
44. Dr. Abbie Stevens, MSU Science Festival 2021 Real exoplanets!
45. Search on YouTube for ‘Kepler orrery’ Dr. Abbie Stevens, MSU Science Festival 2021
46. 4,000+ confirmed exoplanets another 2,000+ candidates as of August 8, 2018 52 are ‘habitable’ Dr. Abbie Stevens, MSU Science Festival 2021
47. Image: PHL at UPR Arecibo Dr. Abbie Stevens, MSU Science Festival 2021
48. • Closest exoplanets: 4.2 light years Alpha Centauri B b Proxima b • Closest habitable exoplanet: 1,200 light years Kepler-62f Image credits: PHL @ UPR Arecibo Dr. Abbie Stevens, MSU Science Festival 2021 Could we ever get to one?
49. Bicycle: ~14mi/h Magical space bicycle from ISS: ~220,000,000 years to Alpha Centauri Bb ~62,000,000,000 years to Kepler-62f Apollo 10: ~40,000mi/h max* Fastest a human has ever gone*: ~71,000 years to Alpha Centauri Bb ~20,000,000 years to Kepler-62f * 2002 Guinness Book of World Records Dr. Abbie Stevens, MSU Science Festival 2021 Could we ever get to one?
50. So, realistically, we’d have to travel faster than the speed of light. Or at least reach relativistic velocities. Dr. Abbie Stevens, MSU Science Festival 2021 Could we ever get to one?
51. So, realistically, we’d have to travel faster than the speed of light. Or at least reach relativistic velocities. Or say goodbye to Earth then somehow safely cryogenically hibernate for a long time. Dr. Abbie Stevens, MSU Science Festival 2021 Could we ever get to one?
52. So, realistically, we’d have to travel faster than the speed of light. Or at least reach relativistic velocities. Or say goodbye to Earth then somehow safely cryogenically hibernate for a long time. Dr. Abbie Stevens, MSU Science Festival 2021 Could we ever get to one? There’s no place like home. Warm, wet and with an atmosphere that’s just right, Earth is the only place we know of with life – and lots of it. JPL’s Earth science missions
53. “It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known.” - Carl Sagan, Pale Blue Dot: A Vision of the Human Future in Space Image by Voyage 1, 1990, 6 billion km from Earth Dr. Abbie Stevens, MSU Science Festival 2021
54. Thank you! Resources: NASA: exoplanets.nasa.gov Planetary Habitability Laboratory: phl.upr.edu Exoplanet Orbit Database: exoplanets.org LCOGT Agent Exoplanet: agentexoplanet.lco.global/ Zooniverse Planet Hunters TESS: zooniverse.org/projects/nora-dot- eisner/planet-hunters-tess Dr. Abbie Stevens, MSU Science Festival 2021
55. Dr. Abbie Stevens, MSU Science Festival 2021 Want to get involved?
56. Dr. Abbie Stevens, MSU Science Festival 2021 Want to get involved?
57. Dr. Abbie Stevens, MSU Science Festival 2021