Kamikaze galaxy explodes after diving into the Milky Way | New Scientist
https://www.newscientist.com/...le/2106019-kamikaze-galaxy-explodes-after-diving-into-the-milky-way/
At least 50 galaxies orbit our own. The Hercules dwarf is currently 460,000 light years from Earth,
nearly three times farther than the Milky Way’s brightest satellite galaxy, the Large Magellanic Cloud.
But Hercules’s stars spread over a great expanse of space, which suggests the Milky Way’s gravitational
pull has yanked them away from one another.
Now Andreas Küpper and Kathryn Johnston at Columbia University in New York and their colleagues have
used the observed positions and velocities of the galaxy’s stars to deduce its path through space.
“It’s plunging in from a really large distance to a really close distance,” Johnston says.
The astronomers calculate that, at its farthest, the dim galaxy voyages 600,000 light years from
the Milky Way’s centre. At its closest, though, it’s just 16,000 light years out.
“That’s extreme,” Küpper says. It’s closer than any other satellite galaxy is known to come. It’s even
closer than we are – the sun is 27,000 light years from the galactic centre.