Astronomers confirm third-ever sighted protoplanet

Through the looking glass: Those following science news have likely seen a fair number of recent stories regarding the discovery of exoplanets, black holes, and galaxies that defy current scientific understanding. However, scientists recently announced one of the rarest findings in astronomy – a planet still being born.

Astronomers at the European Southern Observatory recently confirmed the existence of a protoplanet – a planet currently in the early stages of its formation. Very few definite examples of known exoplanets currently exist.

The new planet is a gas giant orbiting the star HD 169142, which astronomers have observed for several years. The star initially garnered interest because it’s surrounded by a protoplanetary disc – a disc of gas and dust that eventually coalesces into a system of planets through the forces of gravity. Scientists think such a disc surrounded our sun before it formed the planets we know today, including Earth.

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Eventually, astronomers noticed a gap in the disc surrounding HD 169142, suggesting a planet was forming in that region. Further observation with the sphere instrument of the European Southern Observatory’s Very Large Telescope revealed an object moving through the gap at speeds consistent with a planet of that distance from the star, allowing scientists to confirm the existence of a protoplanet. The object is also surrounded by dust which could be coalescing into moons.

The planet, designated HD 169142b, is a gas giant with about three times the mass of Jupiter. It orbits its star at 37 astronomical units – 37 times the distance between Earth and the sun – and takes about 166 years to orbit the star. The system is located 371 lightyears from Earth – practically in the same neighborhood as the solar system in cosmological terms.

Two other confirmed protoplanets are PDS 70b and PDS 70c, discovered in 2018 about 369 lightyears from Earth. Like HD 169142b, they are gas giants of a few Jupiter masses. Findings like this will help scientists better understand how Jupiter-like planets form.

Other recent space discoveries include an asteroid with a slight chance of hitting Earth on Valentine’s Day in 2046, a runaway supermassive black hole leaving a trail of young stars in its wake, and an incredibly detailed picture of a supernova. The Supernova is one of several recent impressive images from the James Webb Telescope.