Artist's concept of an intermediate-mass black hole. Photo: NASA/JPL-Caltech
Scientists may need to cast a wide net, searching across a range of frequencies in order to find never-before-observed intermediate-mass black holes if they crash together in deep space, according to a study in Nature Astronomy this week.
Why it matters: Intermediate-mass black holes — those that are 100–100,000 times the mass of the Sun — represent a gap in humanity's understanding of the universe and could be key to figuring out just how our cosmos evolved over time.
What they found: LIGO can, in theory, pick up ripples in space-time from intermediate-mass black holes today, but according to the new study, it will take future detectors to get a more complete view of the mysterious objects.
- The space-based LISA observatory — which is expected to launch in the 2030s — will be able to search for those gravitational waves at lower frequencies than LIGO.
- That range of frequencies between the instruments will allow scientists on the ground to observe these types of black holes and others as they spiral in toward each other for extended periods of time before merging.
- "If LISA sees it, that means it is going to appear in LIGO's [frequency] band four years later," Karan Jani, an author of the new study, told Axios.
What's next: New ground-based observatories could also help scientists parse signal from noise and find direct evidence if these types of black holes exist.
- Scientists aren’t just looking for these types of black holes through gravitational waves, either. Astronomers have found a number of candidate intermediate-mass black holes through X-ray signatures as well.