Posted on 02/09/2022 9:01:59 AM PST by Red Badger
Microlensing strikes again. Astronomers have been using the technique to detect everything from rogue planets to the most distant star ever seen. Now, astronomers have officially found another elusive object that has long been theorized, and that Universe Today first reported on back in 2009 but has never directly detected – a rogue black hole.
That detection comes at the end of a 6-year observational campaign, with dozens of authors collaborating on a paper recently published in arXiv (meaning it has not yet been peer-reviewed). Those six years of painstakingly gathered data all started back in 2011, when a star about 20,000 light-years away brightened suddenly. Scientists were looking for just such an event and had found several before but needed more data to be sure of what they were actually seeing.
VIDEO AT LINK................
Microlensing leaves two tell-tale signs. The object in the background of a microlensing event would grow significantly bright, as was seen with this star in 2011. In addition, and if the positioning were lucky enough, telescopes would see the star shift ever so slightly as the massive lensing object passed in front of it.
Past observations have shown plenty of brightening events that microlenses might have caused, but astronomers have never before seen the positional shift that would confirm that theory. Kailash Sahu and his colleagues turned Hubble, which is still one of the most functional observation platforms in humanity’s arsenal, toward the star a few weeks after its original brightening. They then checked back in with it periodically over the course of the next six years. In that time frame, they also collected positional data, hoping to use a technique called astrometry to detect slight movements that would indicate the star was subject to a microlensing object between itself and Hubble.
VIDEO AT LINK........................
A combination of warping and amplification of the star’s light is exactly what Hubble saw. But even that wasn’t conclusive enough to prove that the heavy object in front of the star was a black hole – just that it was heavy enough to cause a microlensing effect. To rule out other potential sources of the microlens, Sahu and his colleagues checked the light level of the lens itself. They did not find any, which would have been the case if another object, such as a brown dwarf, was the cause of the lens. Also, the duration of the lensing effect must last long enough to suggest a particularly deep gravity well. The original event in 2011 lasted 300 days, enough to point to a black hole that weighs approximately 7.1 times that of the sun.
With that weight estimate, scientists were also able to estimate how fast the black hole was moving and came up with around 45 kilometers per second – much faster than the stars surrounding it in that area of the Milky Way. Such a speed differential also points to a potential source of the black hole itself – an explosion from a supermassive star probably both created the black hole and kicked it on its way. Sahu estimates the event happened around 100 million years ago, but it is hard to tell as there is no clear, traceable path to where the black hole came from.
VIDEO AT LINK...............
Even without that clear, traceable path, scientists have now definitively found something they have long sought, and they won’t be alone in doing so. Several all-sky surveys are popping up soon that will help scientists consistently scan the skies for events like that in June 2011, and they will most likely find plenty more. That isn’t to say that any of these hard-to-see masses of gravity will prove a threat to Earth, but the more we leverage new techniques like microlensing, the more likely we are to find any that eventually might be.
Originally published on Universe Today.
Kamala?
“only 5000 light years”
That’s 1/20th of the diameter of the entire galaxy, so I think we’re probably safe.
For now........................
Only....
How did Whoopee get so far out?
What if the entire universe is contained in one black hole
+++++
Be patient. It will be one day. Not pleasant living for sure.
The way Stacey Abrams could impress me would be if she ate a whole Rhinoceros in one sitting.
More cool space stuff. Reminds me of a 1950s TV series...Rod Brown of the Rocket Rangers. I looked it up and found why today’s liberals would HATE it:
All Junior Rocket Rangers agreed to abide by the following oath:
“On my honour as a Rocket Ranger, I pledge that:
I shall always chart my course according to the Constitution of the United States of America
I shall never cross orbits with the rights and beliefs of others
I shall blast at full space speed to protect the weak and innocent
I shall stay out of collision orbit with the law of my state and community
I shall cruise in parallel orbit with my parents and teachers
I shall not roar my rocket unwisely, and shall be courteous at all times
I shall keep my gyros steady and my reactors burning by being industrious and thrifty
I shall keep my scanner tuned to learning and remain coupled to my studies
I shall keep my mind out of free-fall by being mentally alert
I shall blast the meteors from the paths of other people by being kind and considerate”
The theme song:
Zooming fast, into the black we race
Rocket Rangers all
Roaring past, blazing a trail in space
With pride we stand, never to fall
Thundering on, ready to fight for right
Let the rockets roar
From the sands of Mars, out to the distant stars
We’re the Rocket Ranger Corps
From the sands of Mars, out to the distant stars
We’re the Rocket Ranger Corps
Is this about DC?
Swallowing up planets and entire solar systems as it moves thru the galaxy.
Civilizations being destroyed.
Cliff Robertson as Rod Brown, Rocket Ranger.
Sounds a lot like Socialism..................
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