TRAPPIST-1 Family of Planets: Rocky Through and Through?
Precise measurements reveal that the exoplanets have remarkably similar densities, which provides clues to their composition
Measuring the mass and diameter of a planet reveals its density, which can give scientists clues about its composition. Scientists now know the density of the seven TRAPPIST-1 planets with a higher precision than any other planets in the universe, other than those in our own solar system. Credit: NASA/JPL-Caltech.
The more precisely scientists can measure a planet’s density, the more they know about what it’s made of. The TRAPPIST-1 planetary system home to the largest batch of roughly Earth-sized planets ever found has offered astronomers a glimpse at the possible diversity among rocky worlds in the universe, including the Earth.
Artist’s depiction of the TRAPPIST-1 star and its seven worlds.NASA/JPL-Caltech/R. Hurt (IPAC)
The TRAPPIST-1 star system is home to the largest batch of roughly Earth-size planets ever found outside our solar system. Discovered in 2016 some 40 light-years away, these seven rocky siblings offer a glimpse at the tremendous variety of planetary systems that likely fill the universe.
A study accepted by the Planetary Science Journal shows that the planets share similar densities. That could mean they all contain roughly the same ratio of materials thought to be common to rocky planets, such as iron, oxygen, magnesium and silicon. If so, then while the TRAPPIST-1 planets might be similar to each other, they appear to differ notably from Earth: They’re about 8% less dense than they would be if they had the same chemical composition as our planet.
Artist’s depiction of the TRAPPIST-1 star and its seven worlds.NASA/JPL-Caltech/R. Hurt (IPAC)
The TRAPPIST-1 star system is home to the largest batch of roughly Earth-size planets ever found outside our solar system. Discovered in 2016 some 40 light-years away, these seven rocky siblings offer a glimpse at the tremendous variety of planetary systems that likely fill the universe.
A study accepted by the Planetary Science Journal shows that the planets share similar densities. That could mean they all contain roughly the same ratio of materials thought to be common to rocky planets, such as iron, oxygen, magnesium and silicon. If so, then while the TRAPPIST-1 planets might be similar to each other, they appear to differ notably from Earth: They’re about 8% less dense than they would be if they had the same chemical composition as our planet.
New year, same #USNavy!
2020 threw its best punch, and we re still standing. 2021, let s see what you got.#HappyNewYearpic.twitter.com/LzPTU5uvaK U.S. Navy (@USNavy) January 1, 2021
To all the men and women of the DOD and their families serving around the globe and at home, Happy New Year! pic.twitter.com/gzBcMpjydv Department of Defense (@DeptofDefense) January 1, 2021
From all of us @SpaceForceDoD, we wish you a healthy & happy New Year! #SemperSuprapic.twitter.com/sMIbhnj7fn United States Space Force (@SpaceForceDoD) January 1, 2021
And Finally, a reflection of 2020 from NASA in this year of chaos.
Chaos at the Heart of the Orion Nebula