Data from ESA’s Gaia spacecraft indicate a large galaxy collided with the Milky Way about 10 billion years ago, leaving identifiable stars strewn in its wake to help astronomers piece together our galaxy’s history.
Using data from ESA’s Gaia and Hipparcos satellites, astronomers have managed to deduce the mass of a giant exoplanet orbiting Beta Pictoris by studying subtle changes in the star’s motion over a quarter of a century.
The Hubble constant indicates how fast the Universe is expanding in the wake of the Big Bang. New observations using two independent techniques have come up with different values, signs of possible problems with current theory.
A head-on collision between the Milky Way and a smaller body dubbed the “Sausage” galaxy eight to 10 billion years ago had a profound effect on the structure and evolution of Earth’s home in space, astronomers say.