New simulations suggest supernova explosions of the Universe\u2019s first stars scattered the ingredients for rocky planets only 100 million years after the Big Bang, with water already present in some planet-forming disks.<\/p>\n
This artist\u2019s impression shows a field of Population III stars as they would have appeared a mere 100 million years after the Big Bang. Image credit: NOIRLab \/ NSF \/ AURA \/ J. da Silva \/ Spaceengine.<\/p>\n
Some of the very first stars in the Universe were enormous and ended their lives in powerful explosions.<\/p>\n
Known as Pop III supernovae, these catastrophic events scattered huge amounts of the chemical elements needed to build planets, such as carbon, oxygen and iron, into the surrounding gas.<\/p>\n
\u201cOur new paper shows that the precursors of terrestrial planets can form around low-mass, long-lived stars in the debris of the first cosmic explosions 100 million years after the Big Bang,\u201d said University of Portsmouth astrophysicist Dr. Daniel Whalen.<\/p>\n
\u201cTo put this into perspective, the Universe is about 13.8 billion years old, so this is remarkably early in cosmic history.\u201d<\/p>\n
A particular type of Pop III supernova, called a pair-instability supernova, is so powerful that it can blast out more than 100 times the mass of the Sun\u2019s worth of heavy elements in a single explosion.<\/p>\n
This material can enrich nearby clouds of gas to surprisingly high concentrations of heavy elements.<\/p>\n
Those enriched clouds can then collapse under gravity and form a swirling disk of material around a young star, much like the disk from which our own Solar System formed.<\/p>\n
\u201cIn our computer simulations of the early Universe, we found one such disk around a young star about 70% as massive as the Sun,\u201d Dr. Whalen said.<\/p>\n
\u201cWithin the disk, enough solid material accumulated to create several Earth-masses\u2019 worth of planetary building blocks at roughly the same distance from the star as Earth is from the Sun.\u201d<\/p>\n
\u201cMost surprisingly, the disk also contained substantial amounts of water, only a few times less than what was available when our own Solar System formed.\u201d<\/p>\n
\u201cThis means that any planets forming there could potentially have received water in a similar way to Earth, which is thought to have gained much of its water from material left over during the planet-building process.\u201d<\/p>\n
\u201cOur findings suggest that the conditions for planet formation may have existed much earlier than previously thought.\u201d<\/p>\n
\u201cIf that\u2019s the case, it raises an intriguing question: could potentially habitable worlds have appeared far earlier in the Universe\u2019s history as well?\u201d<\/p>\n