Stars in a dwarf galaxy (bottom) orbiting around a larger system (top) are stripped away, forming long tails of stars (Illustration: E. D’Onghia/CfA)
WHEN two dwarf galaxies meet, the larger one will steal almost all of the smaller galaxy’s stars.
It had been a mystery how some dwarf galaxies can be so devoid of stars, while remaining full of dark matter. Now computer simulations by Elena D’Onghia of Harvard University and colleagues have shown show that it can happen when a smaller galaxy starts orbiting a larger one.
The orbital period sometimes ends up matching the time it takes the…
