Sign up for our daily briefing

Make your busy days simpler with Axios AM/PM. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Denver news in your inbox

Catch up on the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Des Moines news in your inbox

Catch up on the most important stories affecting your hometown with Axios Des Moines

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Minneapolis-St. Paul news in your inbox

Catch up on the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tampa Bay news in your inbox

Catch up on the most important stories affecting your hometown with Axios Tampa Bay

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Charlotte news in your inbox

Catch up on the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Illustration: Eniola Odetunde/Axios

Astronomers have found indirect evidence of a new type of black hole, and they're now making advances toward seeing one for the first time.

Why it matters: Known as intermediate-mass black holes, these mysterious objects could be the key to unlocking how galaxies evolved, revealing more about why our universe looks the way it does.

The big picture: Black holes are an extreme laboratory by which sweeping theories can be put to the test.

  • They are where the laws of cosmology, general relativity and quantum physics that govern the largest and smallest processes in the universe combine.
  • If there is another type of black hole out there that astronomers have yet to discover, it will play a critical role in piecing together how our universe evolved, experts say.

Details: Scientists think intermediate-mass black holes may exist, but it's not clear how they form or where exactly they might be hiding today.

  • These types of black holes — which are thought to be about 100–100,000 times the mass of the Sun — are too large to have formed during the death of a star but too small to be considered supermassive black holes like the one found in the center of the Milky Way.
"If you have a small and a large, it's weird to just not have the medium."
— NASA astronomer Varoujan Gorjian told Axios

Where it stands: Astronomers have found dozens of possible intermediate-mass black holes, yet none have been confirmed.

  • The LIGO and Virgo detectors are sensitive enough to pick up on gravitational waves sent out during the collision of two intermediate-mass black holes.
  • Astronomers also hope that X-ray observatories could detect how these black holes might affect gas, dust and other objects around them, however, the light emitted during feeding frenzies may not be quite luminous enough to see from Earth with our current tools.
  • Gravitational waves "would give you the smoking gun, that direct measurement of the mass of these objects," LIGO's Salvatore Vitale told Axios.

Yes, but: If they do collide, intermediate-mass black holes likely produce strong gravitational waves at a frequency that competes with seismic activities on Earth — like cars driving by or waves crashing on the shore — making them harder for LIGO and Virgo to distinguish.

What's next: The European Space Agency's LISA mission — expected to launch in the mid-2030s — will be able to measure mergers between intermediate-mass black holes even in the distant universe, hopefully giving scientists an answer to the mystery once and for all.

Go deeper: Event Horizon Telescope hopes to produce first-ever moving image of a black hole

Go deeper

DOJ watchdog to probe whether officials sought to alter election results

Former President Donald Trump and former First Lady Melania Trump exit Air Force One in West Palm Beach, Florida, on Jan. 20. Photo: Alex Edelman/AFP via Getty Images

The Justice Department's inspector general will investigate whether any current or former DOJ officials "engaged in an improper attempt to have DOJ seek to alter the outcome" of the 2020 election, the agency announced Monday.

Driving the news: The investigation comes in the wake of a New York Times report that alleged that Jeffrey Clark, the head of DOJ's civil division, had plotted with President Trump to oust acting Attorney General Jeffery Rosen in a scheme to overturn the election results in Georgia.

1 hour ago - Podcasts

Google's chief health officer Karen DeSalvo on vaccinating America

Google on Monday became the latest Big Tech company to get involved with COVID-19 vaccinations. Not just by doing things like incorporating vaccination sites into its maps, but by helping to turn some of its offices and parking lots into vaccination sites.

Axios Re:Cap goes deeper into what Google is doing, and why now, with Dr. Karen DeSalvo, Google's chief health officer who previously worked at HHS and as health commissioner for New Orleans.

Biden signs order overturning Trump's transgender military ban

Photo: Tom Brenner/Getty Images

President Biden signed an executive order on Monday overturning the Trump administration's ban on transgender Americans serving in the military.

Why it matters: The ban, which allowed the military to bar openly transgender recruits and discharge people for not living as their sex assigned at birth, affected up to 15,000 service members, according to tallies from the National Center for Transgender Equality and Transgender American Veterans Association.