Categories: Black Holes

Roman Space Telescope Will Also Find Rogue Black Holes

In the past we’ve reported about how the Roman Space Telescope is going to potentially be able to detect hundreds of thousands of exoplanets using a technique known as “microlensing”. Exoplanets won’t be the only things it can find with this technique though – it should be able to find solitary black holes as well.

Solitary black holes are unique, as most black holes that scientists have “found” are those that are directly interacting with another object.  However, those that are relatively small that could be roving around the galaxy by themselves which would be almost impossible to find since they absorb all electromagnetic wavelengths. 

UT video describing microlensing

Usually these small black holes weigh around  10 times the weight of the sun.  They form when a star dies and either goes supernova or collapses directly into a black hole, depending on its weight.  If the black hole isn’t surrounded by any gas or dust to absorb, it would then become essentially invisible to almost all instruments.

So far scientists have found 20 of these “stellar mass” black holes, but only because they are next to a different astronomical object, making their gravitational force apparent in the way that companion object moves.

NASA Video describing how to use gravitational lensing to detect black holes.
Credit: NASA

The neat thing about the microlensing technique that Roman will use to detect planets is that any large gravitational field will cause the microlensing effect.  So if Roman sees what appears to be a microlensing effect around something where there is not an obvious source of mass, it is likely to be a black hole causing it.

In order to find the slight disturbances that would cause the microlensing, Roman will have to stare at hundreds of millions of stars for a very long time.  But that is exactly what it is designed to do.  With this additional data, scientists will be able to answer questions such as why solitary black holes only seem to mass around 10x what the sun does, or exactly how many stellar-mass black holes there are in the galaxy. The current estimate is around 100 million.

UT video discussing the prevalence of black holes.

No matter the answers to these questions, Roman will provide more data to inform conclusions on these questions and many others when it launches around 2025.

Learn More:
NASA – How NASA’s Roman Space Telescope Will Uncover Lonesome Black Holes
UT – What’s the Connection Between Stellar-Mass Black Holes and Dark Matter?
UT – How Much of the Universe is Black Holes?

Lead Image:
Graphic showing how microlensing around a black hole would work.
Credit: NASA’s Goddard Space Flight Center Conceptual Image Lab

Andy Tomaswick

Recent Posts

Planetary Geophysics: What is it? What can it teach us about finding life beyond Earth?

Universe Today has examined the importance of studying impact craters, planetary surfaces, exoplanets, astrobiology, solar…

5 hours ago

This New Map of 1.3 Million Quasars Is A Powerful Tool

Quasars are the brightest objects in the Universe. The most powerful ones are thousands of…

10 hours ago

Webb Finds Hints of a Third Planet at PDS 70

The exoplanet census now stands at 5,599 confirmed discoveries in 4,163 star systems, with another…

10 hours ago

Improving a 1960s Plan to Explore the Giant Planets

In the 1960s, NASA engineers developed a series of small lifting-body aircraft that could be…

11 hours ago

Finally, an Explanation for the “String of Pearls” in Supernova 1987A

Not long after the explosion of Supernova 1987a, astronomers were abuzz with predictions about how…

12 hours ago

NASA is Working on Zero-Boil Off Tanks for Space Exploration

No matter what mode of transportation you take for a long trip, at some point,…

14 hours ago