Kepler-444: The Planets We've Found That Are Older Than Almost Everything in the Universe
Sleep On Astrophysics
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What if planets existed billions of years before Earth was even possible? Kepler-444 is a system of five rocky worlds that formed nearly 11 billion years ago, when the universe was barely 2.6 billion years old and almost entirely made of hydrogen and helium. According to our best models of planet formation, these worlds shouldn't exist. Rocky planets need heavy elements like iron, silicon, and magnesium, materials that simply weren't abundant enough in the early universe. And yet, five confirmed terrestrial planets orbit this ancient star, older than almost everything visible in tonight's sky.
In this video, we explore how asteroseismology revealed Kepler-444's extraordinary age, why the metal-poor early universe should have made rocky planet formation nearly impossible, the other ancient planetary systems, including the 12.7-billion-year-old Methuselah planet, that deepen this mystery, and what 11 billion years of existence has done to these worlds. This is the story of a universe that started building planets almost as soon as it possibly could, and what that means for everything we thought we knew about how worlds are made.
Sources:
Campante, T.L. et al. (2015). "An ancient extrasolar system with five sub-Earth-size planets." The Astrophysical Journal, 799(2), 170.
https://doi.org/10.1088/0004-637X/799...
Sigurdsson, S. et al. (2003). "A Young White Dwarf Companion to Pulsar B1620−26: Evidence for Early Planet Formation." Science, 301(5634), 193–196.
https://doi.org/10.1126/science.1086326
Lacedelli, G. et al. (2021). "TOI-561 b: A rocky super-Earth on a 10.5-hour orbit around a metal-poor star." Monthly Notices of the Royal Astronomical Society, 501(3), 4148–4166.
https://doi.org/10.1093/mnras/staa3728
Batalha, N.M. et al. (2011). "Kepler's First Rocky Planet: Kepler-10b." The Astrophysical Journal, 729(1), 27.
https://doi.org/10.1088/0004-637X/729...
Fischer, D.A. & Valenti, J. (2005). "The Planet-Metallicity Correlation." The Astrophysical Journal, 622(2), 1102–1117.
https://doi.org/10.1086/428383
#AncientPlanets #Kepler444 #Exoplanets #SpaceScience #PlanetFormation #Astronomy #Universe
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Kepler-444: The Planets We've Found That Are Older Than Almost Everything in the Universe
Sleep On Astrophysics
6,730 views
What if planets existed billions of years before Earth was even possible? Kepler-444 is a system of five rocky worlds that formed nearly 11 billion years ago, when the universe was barely 2.6 billion years old and almost entirely made of hydrogen and helium. According to our best models of planet formation, these worlds shouldn't exist. Rocky planets need heavy elements like iron, silicon, and magnesium, materials that simply weren't abundant enough in the early universe. And yet, five confirmed terrestrial planets orbit this ancient star, older than almost everything visible in tonight's sky.
In this video, we explore how asteroseismology revealed Kepler-444's extraordinary age, why the metal-poor early universe should have made rocky planet formation nearly impossible, the other ancient planetary systems, including the 12.7-billion-year-old Methuselah planet, that deepen this mystery, and what 11 billion years of existence has done to these worlds. This is the story of a universe that started building planets almost as soon as it possibly could, and what that means for everything we thought we knew about how worlds are made.
Sources:
Campante, T.L. et al. (2015). "An ancient extrasolar system with five sub-Earth-size planets." The Astrophysical Journal, 799(2), 170.
https://doi.org/10.1088/0004-637X/799...
Sigurdsson, S. et al. (2003). "A Young White Dwarf Companion to Pulsar B1620−26: Evidence for Early Planet Formation." Science, 301(5634), 193–196.
https://doi.org/10.1126/science.1086326
Lacedelli, G. et al. (2021). "TOI-561 b: A rocky super-Earth on a 10.5-hour orbit around a metal-poor star." Monthly Notices of the Royal Astronomical Society, 501(3), 4148–4166.
https://doi.org/10.1093/mnras/staa3728
Batalha, N.M. et al. (2011). "Kepler's First Rocky Planet: Kepler-10b." The Astrophysical Journal, 729(1), 27.
https://doi.org/10.1088/0004-637X/729...
Fischer, D.A. & Valenti, J. (2005). "The Planet-Metallicity Correlation." The Astrophysical Journal, 622(2), 1102–1117.
https://doi.org/10.1086/428383
#AncientPlanets #Kepler444 #Exoplanets #SpaceScience #PlanetFormation #Astronomy #Universe