Karl Schwarzchild in 1916 theorized about the existence Black holesAs a solution to Einstein’s field equations Theory of General Relativity.
Astronomers discovered black holes in the mid-20th-century by using indirect methods. These consisted of studying their effects on space and objects around them.
Scientists have been studying supermassive black hole (SMBHs) since the 1980s. They are located at the center most massive galaxies of the Universe. By April 2019, there were a total of 58 SMBHs. Event Horizon Telescope (EHT) collaboration ReleasedThis is the first photograph ever taken by an SMBH.
These observations offer an opportunity to test laws of Physics under extreme conditions and give insight into the forces shaping the Universe.
According to a RecentStudy, an international research team used data from the ESA to support their study Gaia ObservatoryTo observe a strangely orbiting Sun-like star. The team concluded that the star must be part of an interstellar system because of the peculiar orbital characteristics. Black holeBinary system.
This makes it the nearest Black Hole to our Solar System. It also implies that there is a significant population of dormant Black Holes in our Galaxy.
Kareem El Badry, a Harvard Society Fellow astrophysicist and the principal investigator of this research, was responsible for it. Harvard-Smithsonian Center for Astrophysics(CfA and the Max Planck Institute for Astronomy (MPIA).
Researchers from CfA (MPIA), Caltech, UC Berkeley and the Flatiron Institute were there to support him. Center for Computational Astrophysics(CCA), Weizmann Institute of ScienceThe Observatoire de Paris, MIT’s Kavli Institute for Astrophysics and Space ResearchMultiple universities.
The PaperThis will publish the findings of the researchers. Monthly Notices of The Royal Astronomical Society.
Universe Today was informed by El-Badry via email that these observations were part a larger campaign to find dormant companions for normal stars in our Milky Way galaxy.
He said, “I have been searching for dormant dark holes for the past four years using a wide variety of datasets and techniques.”
“My previous efforts turned up a variety of binaries masquerading as black holes, but this is the first time that the search has yielded any results.”
El-Badry’s colleagues used data from ESA’s Gaia Observatory to help them in their study. Nearly a decade has passed since the mission measured the positions, distances and proper motions for nearly 1 billion astronomical objects such as stars and planets, asteroids and comets.
The Gaia mission uses a technique called Astrometry to track the movements of objects as they orbit around the center of Milky Way. This is a method known as Astrometry. It aims at creating the most precise 3D space catalog ever made.
El-Badry and his coworkers examined all stars of the Gaia Data Release 3 (3 (GDR3)) that had two-body orbits.
Their analysis found a particularly promising candidate, a G-type (yellow star) designated Gaia DR3 4373465352415301632 – for their purposes, the team designated it Gaia BH1. El-Badry, along with his colleagues, determined that the star must have an orbital companion.
El-Badry stated: “The Gaia data constrain the star’s movement in the sky. They trace out an ellipse that it orbits the black holes. The size of the orbit and its period give us a constraint on the mass of its unseen companion – about 10 solar masses.
We used several telescopes to observe the star spectroscopically in order to confirm the Gaia solution. This confirmed that the companion is indeed dark, as it tightened our limits on its mass.
The team analyzed radial velocity measurements from Gaia BH1 using multiple telescopes to confirm their observations.
These included the W. M. Keck Observatory High-Resolution Echelle Scotrometer (HIRE), the MPG/ESO telescope’s Fiber-fed Extended Range Optical Spectrograph (FEROS) spectrograph, the Very Large Telescope’s (VLT) X-Shooter spectrographThe Gemini Multi-Object Spectrographs(GMOS), Magellan ElchelletteMagESpectrograph (). Large Sky Area Multi-Object Fibre Spectroscopic Telescope.LAMOST).
Similar to Doppler Spectroscopy, the spectra from these instruments were used to measure and observe the gravitational forces that influenced Gaia BH1’s orbit. These observations confirmed Gaia BH1’s orbital solution, and showed that a companion of approximately 10 solar masses was orbiting alongside it.
These findings, as El-Badry stated, could be the first black hole discovered in the Milky Way.
“Models predict that there are about 100 million black holes in the Milky Way. However, we have only been able to observe about 20. We have only seen the last ones in Xray binaries. The black hole is feeding on a companion star and shines brightly in the X-rays because the material’s gravitational energy is converted into light.
These are just a few of the many possibilities. A much larger population could be hiding in binaries further apart. This population is first exposed by Gaia BH1, which was discovered in early 2012.
These findings, if confirmed, could indicate that there is a large population of dormant dark holes in the Milky Way. This refers to black hole which aren’t visible through bright disks, bursts radiation or hypervelocity jets emitted from their poles (as with quasars).
The implications of this object’s presence in our galaxy could be significant for both stellar and galactic evolution. But it’s possible that this dormant black spot is an exception and is not indicative of a larger number.
El-Badry and his coworkers are excited about Gaia Data Release 4 (“GDR 4”) to verify their findings. The date is yet to be set. It will include all data gathered during the five-year nominal missions (GDR 4).
This release will include the most recent astrometric, photometric and radial-velocity catalogues for all stars and galaxies.
GDR 5 is the fifth and final release. This will include data from both nominal and extended missions (the full 10 year period).
El-Badry stated that based on the BH companion occurrence rates implied by Gaia BH1, it was estimated that the next Gaia Data Release will allow the discovery of dozens similar systems.
“With one object it is hard to know what it reveals about the population. It could just be an anomaly, a fluke. We are excited about the demographic population studies that we will be able do with larger samples.
This article was first published by Universe Today. Please read the Original article.
