One of the most sought-after objects in astronomy appears to be orbited by
a comma-shaped molecular cloud close to the Milky Way's core.
Astronomers precisely saw nothing at the "Tadpole's" orbital center. A
nothing that draws something just shouts "black hole," after all.
The "missing link" intermediate-mass black holes, which are a rare breed of
middleweight black holes, are predicted by modeling to be different from
your average black hole.
If so, it would be the fifth potential intermediate black hole discovered
close to the galactic center.
Astronomers may be able to learn more about the formation and subsequent
growth of the supermassive black holes at the cores of galaxies as a result
of the increasing number of previously elusive objects.
The finding of an isolated, unique compact cloud is reported in this
study by a group of astronomers
from Keio University in Japan, lead by Miyuki Kaneko.
"The Tadpole's spatial compactness and lack of brilliant equivalents in
other wavelengths suggest that the object may be an intermediate-mass black
hole," the author writes.
There are two major mass regimes where black holes are often found in the
universe. There are black holes with stellar masses, which can be up to 100
times as massive as the Sun. These are black holes that are created when the
center of a large star collapses near the conclusion of its life or when two
such black holes unite.
The supermassive black holes come next. These are the enormous chonkers,
millions to billions of times as massive as the Sun, that are found at the
centre of galaxies.
Astronomers would want to find the answer to the cosmic mystery of how
these things arise, which is currently unknown.
Black holes with in-between masses are one site where the solutions could
be located. The discovery of these intermediate-mass black holes (IMBH)
would demonstrate that black holes exist in a spectrum of masses that spans
from titch to behemoth, with the intermediate ones representing a
developmental stage in between.
Nevertheless, very few of these middleweight objects have been located, and
when they have, it has generally only been tentatively.
One issue is that solitary black holes don't produce any light on their
own. Only their powerful gravitational pull on their surroundings, which
sends matter into a raging frenzy, or their specific tugs on space-fabric
time's may be used to identify them.
The orbital dance of far-off objects, like the stars astronomers examined
to confirm the existence of Sagittarius A*, the black hole at the heart of
the Milky Way, can be impacted by this overt drag.
Indeed, the galactic core is a rather crowded location. The sort of
molecular clouds that give rise to stars are abundant there.
The Central Molecular Zone
has a molecular gas density that is many orders of magnitude greater than
the Milky Way disk.
The area is so thick that it might be hard to observe what is inside, but a
strong radio telescope can show the activity inside.
The cloud known as the Tadpole was discovered in this manner by the
researchers. They were searching for gas that had been affected by gravity
using the
James Clerk Maxwell Telescope.
The Tadpole was it—a molecular cloud 27,000 light-years distant, extremely
near the galactic center, and moving in a distinctive manner from the
surrounding material.
The scientists discovered that it had a stretched-out form as a result of
being dragged by a significant tidal force, or gravitational
interaction.
And their simulations revealed that the mass in question is around 100,000
times as massive as the Sun. That clearly implies a black hole in the
middle.
There will always be questions about where it could have originated from
and how it formed.
The team must first verify its suspicions. To see whether scientists can
spot any indications of a black hole or something else at the orbital
center, they want to undertake follow-up studies of the Tadpole using the
powerful Atacama Large Millimeter/submillimeter Array in Chile.
Our knowledge of supermassive black holes may be significantly affected if
it turns out to be an intermediate-mass black hole.
The research has been published in
The Astrophysical Journal.