Billions of celestial objects revealed in survey of the Milky Way
noirlab.edu
noirlab.edu
Why?
Well the Departamento de Energía de Estados Unidos (DOE) (as the article refers to them) is interested in "energy" .. and by "energy" they really mean nuclear weapons.
It was a Cold War thing.
Their interest here is in ground truthing and the elimination of "normal, not a bomb" stuff ... it'd be a bad day if an astro event billions of years in the past triggered a global thermal nuclear war because Bob the nanosecond reflex triggerhappy automaton got confused about a couple of rapidly spinning galactic core black holes eating each out.
Or, as the DOE explains:
https://www.energy.gov/science/doe-explainscosmic-accelerati...
https://www.energy.gov/science/articles/our-expanding-univer...
https://www.energy.gov/science/doe-explainsdark-matter
err, or rather 'explains' but doesn't mention much about the intial rational behind their decades of work with orbiting gamma ray sensors.
Nothing to see here.
Are they sure those are not chinese spy baloons ? You can't be paranoid enough when it comes to "national security" /s