a group of asteroids in front of the Milky Way galaxy
There are ten times more asteroids than astronomers thought according to new data from a space telescope.
The findings come from a huge data release earlier this month from the European Space Agency’s Gaia space telescope, which was launched in 2013 and since then has been gradually creating an ever more detailed 3D map of our Milky Way galaxy.
The so-called “DR3” dataset includes more than 150,000 objects in the solar system objects, most of them asteroids—though also some moons.
“Based on Gaia DR3, Finnish researchers will change the conception of asteroids in our solar system,” said Karri Muinonen, Academy Professor at the University of Helsinki, Finland, which was involved in the new data release.
It’s thought that the new data will enormously help astronomers in calculating accurate orbits for asteroids. That’s because Gaia data adds-in the physical properties of asteroids. Rather than just seeing them as a point of light, its astrometry —precise measurements of the positions and movements—adds data on its size, shape, rotation and surface light scattering properties.
Something the Gaia DR3 data release has also revealed is the color of about 60,000 asteroids, something that was only known for a handful of asteroids beforehand. That’s going to help astronomers determine what they’re made of, which tells a story about where it comes from—and effectively the evolution of the whole Solar System.
The Gaia DR3 data release on June 13, 2022 was a big moment for astronomy that’s not gotten the media coverage it deserves. About 50 scientific articles were published from ground-breaking new data from Gaia on the chemical compositions, temperatures, colors, masses, brightnesses, ages and radial velocities (”wobbles”) of stars.
As well as uncovering many more asteroids than were previously thought to exist, DR3 contains the largest ever binary star catalog for the Milky Way as well as millions of galaxies and quasars beyond our Milky Way.
Gaia launched atop a Soyuz-Fregat rocket on December 19, 2013 from Europe’s spaceport in French Guina and has been observing from the same Lagrange L2-point where the James Webb Space Telescope (JWST) resides. About a million miles/1.6 million kilometers from Earth, it’s at this precise point in space the spacecraft is in gravitational equilibrium in the Earth-Moon-Sun system.
Revolving one every six hours, Gaia observes the stars in vast circles. It studies the cosmos using two optical telescopes and three science instruments, which allow it to measure objects’ positions, how fast they’re moving and what they look like.
So far it’s collected new and/or more detailed data on almost two billion objects in our galaxy and the surrounding cosmos. It’s expected to continue observing through 2025.
Wishing you clear skies and wide eyes.
