© ESO/GRAVITY collaborationThese annotated images, obtained with the GRAVITY instrument on ESO’s Very Large Telescope Interferometer (VLTI) between March and July 2021, show stars orbiting very close to Sgr A*, the supermassive black hole at the heart of the Milky Way.
One of these stars, named S29, was observed as it was making its closest approach to the black hole at 13 billion kilometres, just 90 times the distance between the Sun and Earth. Another star, named S300, was detected for the first time in the new VLTI observations. To obtain the new images, the astronomers used a machine-learning technique, called Information Field Theory. They made a model of how the real sources may look, simulated how GRAVITY would see them, and compared this simulation with GRAVITY observations. This allowed them to find and track stars around Sagittarius A* with unparalleled depth and accuracy.The European Southern Observatory's Very Large Telescope Interferometer (ESO's VLTI) has obtained the deepest and sharpest images to date of the region around the supermassive black hole at the center of the Milky Way. The new images zoom in 20 times more than what was possible before the VLTI and have helped astronomers find a never-before-seen star close to the black hole. By tracking the orbits of stars at the center of the Milky Way, the team has made the most precise measurement yet of the black hole's mass.
"We want to learn more about the black hole at the center of the Milky Way, Sagittarius A*: How massive is it exactly? Does it rotate? Do stars around it behave exactly as we expect from Einstein's general theory of relativity? The best way to answer these questions is to follow stars on orbits close to the supermassive black hole. And here we demonstrate that we can do that to a higher precision than ever before," explains Reinhard Genzel, a director at the Max Planck Institute for Extraterrestrial Physics (MPE) in Garching, Germany who was awarded a Nobel Prize in 2020 for Sagittarius A* research. Genzel and his team's latest results, which expand on their three-decade-long study of stars orbiting the Milky Way's supermassive black hole, are published today in two papers in
Astronomy & Astrophysics.
On a quest to find even more stars close to the black hole, the team, known as the GRAVITY collaboration, developed a new analysis technique that has allowed them to obtain the deepest and sharpest images yet of the galactic center. "The VLTI gives us this incredible spatial resolution, and with the new images, we reach deeper than ever before. We are stunned by their amount of detail, and by the action and number of stars they reveal around the black hole," explains Julia Stadler, a researcher at the Max Planck Institute for Astrophysics in Garching who led the team's imaging efforts during her time at MPE. Remarkably, they found a star, called S300, which had not been seen previously, showing how powerful this method is when it comes to spotting very faint objects close to Sagittarius A*.
This animation shows the orbits of the stars S29 and S55 as they move close to Sgr A* (centre), the supermassive black hole at the heart of the Milky Way. As we follow the stars along in their orbits, we see real images of the region obtained with the GRAVITY instrument on ESO's Very Large Telescope Interferometer (VLTI) in March, May, June and July 2021. In addition to S29 and S55, the images also show two fainter stars, S62 and S300, the latter having only been discovered following these new VLTI observations.
Source: ESO/GRAVITY collaboration/L. CalçadaWith their latest observations, conducted between March and July 2021, the team focused on making precise measurements of stars as they approached the black hole. This includes the record-holder star S29, which made its nearest approach to the black hole in late May 2021. It passed it at a distance of just 13 billion kilometers, about 90 times the sun-Earth distance, at the stunning speed of 8740 kilometers per second. No other star has ever been observed to pass that close to, or travel that fast around, the black hole.
The team's measurements and images were made possible thanks to GRAVITY, a unique instrument that the collaboration developed for ESO's VLTI, located in Chile. GRAVITY combines the light of all four 8.2-meter telescopes of ESO's Very Large Telescope (VLT) using a technique called interferometry. This technique is complex, "but in the end you arrive at images 20 times sharper than those from the individual VLT telescopes alone, revealing the secrets of the galactic center," says Frank Eisenhauer from MPE, principal investigator of GRAVITY.
"Following stars on close orbits around Sagittarius A* allows us to precisely probe the gravitational field around the closest massive black hole to Earth, to test General Relativity, and to determine the properties of the black hole," explains Genzel. The new observations, combined with the team's previous data, confirm that the stars follow paths exactly as predicted by general relativity for objects moving around a black hole of mass 4.30 million times that of the sun. This is the most precise estimate of the mass of the Milky Way's central black hole to date. The researchers also managed to fine-tune the distance to Sagittarius A*, finding it to be 27,000 light-years away.
This zoom video sequence starts with a broad view of the Milky Way. We then dive into the dusty central region to take a much closer look. There, a swarm of stars orbit around an invisible object: a supermassive black hole, 4.3 million times that of the Sun. As we get closer to it, we see these stars, as observed by the NACO instrument on ESO's Very Large Telescope (the last observation being from 2019). As we zoom in further, we see stars even closer to the black hole, observed with the GRAVITY instrument on ESO's Very Large Telescope Interferometry in mid-2021.
Credit: ESO/GRAVITY collaboration/L. Calçada, N. Risinger (skysurvey.org), DSS. Music: Johan MonelTo obtain the new images, the astronomers used a machine-learning technique called information field theory. They made a model of how the real sources may look, simulated how GRAVITY would see them, and compared this simulation with GRAVITY observations. This allowed them to find and track stars around Sagittarius A* with unparalleled depth and accuracy. In addition to the GRAVITY observations, the team also used data from NACO and SINFONI, two former VLT instruments, as well as measurements from the Keck Observatory and NOIRLab's Gemini Observatory in the US.
GRAVITY will be updated later this decade to GRAVITY+, which will also be installed on ESO's VLTI and will push the sensitivity further to reveal fainter stars even closer to the black hole. The team eventually aims to find stars so close that their orbits would feel the gravitational effects caused by the black hole's rotation. ESO's upcoming Extremely Large Telescope (ELT), under construction in the Chilean Atacama Desert, will further allow the team to measure the velocity of these stars with very high precision. "With the GRAVITY+ and the ELT's power combined, we will be able to find out how fast the black hole spins," says Eisenhauer. "Nobody has been able to do that so far."
This research was presented in two GRAVITY Collaboration papers to appear in
Astronomy & Astrophysics.More information: R. Abuter et al, Mass distribution in the Galactic Center based on interferometric astrometry of multiple stellar orbits,
Astronomy & Astrophysics (2021).
DOI: 10.1051/0004-6361/202142465
Reader Comments
If you believe the mass of 100 planets can be "smooshed" into a "singularity" smaller than an electron - you are doing violence to your self image - why not form a suicide squad and stab yourself in front of cardboard replicas of "authority figures" .
And the sun is a big hydrogen reactor - give me a farging break.
R.C.
Nope, I were born in Yorkshire and damned proud and it.
The art of this particular Science has lost all credibility, whilst they continue to dangle this nonsensical theory of Black holes I have zero tolerance towards their stupity.
BTW, The girl in a red dress singing "It's beginning to look a lot like fascism" was looking pretty acceptable. I love artists.
How are you?
RC
Concert was surprisingly great.
You bring up a point too few times I've seen noted. "Reasonable accommodation" which tells me that you're ADA aware. Good.
RC
*
"For time immemorial ruthless dictators have known and understood the effectiveness of decimating the food supply of those they wish to oppress. Favorable weather is, of course, essential for staple crop food production. When former US president Lyndon Johnson stated "he who controls the weather, controls the world", is this what he meant? Why would we think otherwise? Are the current controllers any less tyrannical than Johnson? Or, perhaps, far worse? If the aforementioned methods were not getting the job done fast enough, what other tactics should populations have long since expected psychotic rulers to implement? Have we arrived?..." -Dane Wigington
RC
No doubts as they cross the limb of the Sun, they'll be fireworks.
regards Winternights3
*
"As 2021 draws to an end, global controller criminality, climate intervention operations, biosphere implosion and societal collapse, all continue to accelerate exponentially. Climate modification operations remain a primary weapon of the power structure and the military industrial complex that serves them. Increasingly radical weather and temperature extremes are wreaking havoc on infrastructure, ecosystems, food production and thus already struggling societies all over the world. As the great unraveling picks up momentum, the vast majority of media sources (corporate and alternative) are focused on everything but the wider horizon. Biosphere implosion has been, is, and will always be the bottom line factor fueling escalating insanity, chaos and collapse on every front. Thank you for tuning in to this year end extended version of Global Alert News. All are needed in the critical battle to wake populations to what is coming, we must make every day count. Share credible data from a credible source, make your voice heard. Awareness raising efforts can be carried out from your own home computer." -Dane Wigington
Two instances of gamma ray outbusts causing geomagnetic pertubations inbetween a few days/weeks. Which I haven't seen for years, if at all.
This would be the "instant kill shot" mechanism for basically all terrestrial electronics, in difference to the slower proton streams.
I'm not interested in your Christmas sugar rush reactions.
I monitor, I see everything.
Not you. Not I. Not a one of us has a grasp of everything, so get over yourself will you.
Have a little freaking humility. The Winter is fixing to be cold for many People and they do not deserve such poor leadership me thinks. I think this and I think that but I make no claim to everything and anyone who makes such a claim is suspect in my book. I don't care for bold statements such as that. I find them offensive.
So Prove it.
I respect codis and I don't care for the language you have used above WN3 and if you doubt this, then you will force me to prove it to you if I haven't already.
Seriously DUDE get you some humility. I send a humility pill your way and I hope you swallow it all.
RC
Perhaps he just had an upset stomach that spilled over into his mood.
Or he is generally frustrated with the world - and the outpouring aggressiveness will get him banned here eventually.
BK
I thought I'd pop by to enlighten you.
I'm retired and enjoy cooking, my dishes are of the highest standard and I'm always of good spirits.
I'm massively proactive and have many interests, and frustration is something others play as a game, I'm too busy.
Your closing comment exposed your own frustration not mine.
I look forward to exchanging views and opinions in the New year.
But I don't engage in online contentions anymore, they just frustrate me, drain my attention, and pull my mood down. And achieve nothing. Especially if it goes emotional.
I wish you Greetings.
Those born out the realisation that Springtime is on its way and that folk can once again rejoice.
Just saying ...
RC
My wife constantly swears at YT ads on her smartphone, though. Haven't found any adblocker for Android yet, one of the many reason I have no smartphone.
Both are extensions / addons you can install from inside the browser, for free.
RC
Our Sun's magnetic field's are far from stable at present and this is rebounding throughout our Solar System.
If Earth loses its defense of inbound Solar winds by our virtue of Earth's magnetic field movement, then what I witnessed last night will result in a cataclysmic event, no doubt its happened many times before.
I capture the magnetosphere's actions at SWMF-RCM(V01312011), it's a useful site and reports in near real time.
I'm expecting our next dollop of the white stuff 🌨 will be around the 3rd to the 5th of January in the UK, there's the potential for some heafty falls should the cold air merge in the Northern hemisphere.
My compass shows magnetic North now 2.5 / 3 degrees off course, heading East,that's happened in the last 10 years.
Be interested to read your thoughts on what's about to unfold in the Northern hemisphere as Winter moves into Springtime.
That just led me to wonder about my rarest or favorite bird sighting. I've got the bald eagle with the mullet, golden eagle story too, ospreys out the ass. . . So, ah!.... I was driving on 528 from Cocoa to Orlando around 2012? or so and on the right side of the road was a big BIG white wading bird. Perfectly white head (rules out the wood stork - was incorrectly called a wood ibis in my youth) too big to be an american egret/great white heron etc.
What was it? A fucking whooping crane! When I got to Orlando I went online and looked it up - the fucker had its own webpage!
(Clarification: I looked it up and found that they were en route to their recreated migration from Canada down to Kissimmee. Details are saved somewhere.
RC
Bempton Cliffs is where to go if you enjoy a tad of Twitching, my partner and I had an enjoyable day there this year and my partner got to see her beloved Puffins there.
I have a part time interest in geology, so Robin Hoods Bay is where we often go, steeped in history and wonderful walks too.
I always liked geology and rock hounding. Do not attempt same in Florida. RC
On one of our beach hunts for fossils and interesting rocks, I found a beautiful Ammonite, its now on my kitchen windowsill, next to me as I type away
RC
Another anomalous band of cold air extends from the central states of the USA, out a beyond the western seaboard?
There's an established band of the jetstream now tracking the Southern most extends of the cold air mass in the Northern hemisphere.
My only other observation today is that of the disproportionate amount of cold air in the Northern hemisphere compared to the Southern hemisphere, even accounting for seasonal adjustments.
WN3.
But like Bill Clinton, I feel your pain.
RC
Happy & Best New Year!
RC
Note Betty White's passing today. She evidently felt so physically well that she (1) remarked on her condition within this past month and (2) was planning a huge celebration for her 100th birthday in January. Again...no mention of vaccination status. My guess? Yes. Particularly since she died after announcing how well she felt.
It rained right away and all of those 'lint' balls disappeared into the ground.
We're up against otherworldly evil. Hang tough and Happy New Year all!
RC
RC
Lord, please help us awaken our sleepers.
HNY!
RC
There's a potential for a development to occur around the 13th January over Europe.
*Damn, I just love that inside joke. Poe was a pre-SOTT SOTType.
RC
RC
Some I fear are under the influence of some dark star... Thanks for Poe !
*
Chat with Ben live at 4 Pm Eastern! (Sun. 1/9/22)
I'd sure like to discuss with him this:
[Link]
I got a sneaking suspicion info from the NHC may not be accurate - but don't mean the storm isn't serious - I mean the eye seems well formed - but the winds speeds - they seem less per the link above.
I miss that ole codger.
BK