Bright lights detected by NASA telescopes lead to a dancing pair of supermassive black holes
Two telescopes have spotted the closest pair of supermassive black holes to date. The duo, only about 300 light-years apart, were observed in different wavelengths of light using NASA’s Chandra X-ray Observatory and the Hubble Space Telescope.
While black holes are invisible against the dark void of space, these two blaze brightly as the gas and dust they feed on is accelerated and heated to high temperatures. Both celestial objects, which circle around one another, are known as active galactic nuclei.
Active galactic nuclei are supermassive black holes that release bright jets of material and high winds that can shape the very galaxies where they are found.
The black hole duo is the closest pair found through visible and X-ray light. While other black hole pairs have been observed before, they are usually much farther apart. Astronomers discovered these black holes dancing around one another at the center of a pair of colliding galaxies called MCG-03-34-64, which is 800 million light-years away.
Astronomers serendipitously found the black holes when Hubble’s observations revealed three spikes of bright light within the glowing gas of a galaxy. They published their discovery Monday in The Astrophysical Journal.
“We were not expecting to see something like this,” said lead study author Anna Trindade Falcão, a postdoctoral researcher at the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts, in a statement. “This view is not a common occurrence in the nearby universe, and told us there’s something else going on inside the galaxy.”
Zooming in on bright cosmic lights
The team was intrigued when Hubble picked up on three optical diffraction spikes in a concentrated region of the MCG-03-34-64 galaxy. Diffraction spikes appear when light from a small cosmic region bends around the mirror inside telescopes.
Hubble’s observations were made in optical light, which is visible to the human eye, but the astronomers weren’t sure what they were seeing. Falcão’s team took another look at the galactic region with Chandra in X-ray light.
When the scientists observed the galaxy using Chandra, they were able to pinpoint two powerful sources of X-ray light that matched the optical light sources spotted by Hubble, Falcão said. “We put these pieces together and concluded that we were likely looking at two closely spaced supermassive black holes.”
The team also consulted archival observation radio wave data collected by the Karl G. Jansky Very Large Array of radio telescopes near Socorro, New Mexico. The black hole duo was also found to release energetic radio waves.
“When you see bright light in optical, X-rays, and radio wavelengths, a lot of things can be ruled out, leaving the conclusion these can only be explained as close black holes. When you put all the pieces together it gives you the picture of the (active galactic nuclei) duo,” Falcão said.
Meanwhile, the third diffraction spike observed by Hubble has an unknown origin, and the team requires more data to understand what it could be. The source of light might be from gas that was shocked by an energetic release of material from one of the black holes.
“We wouldn’t be able to see all of these intricacies without Hubble’s amazing resolution,” Falcão said.
Astronomers have observed pairs of black holes that are closer together than these two through radio telescopes, but those duos haven’t been observed in other wavelengths of light.
Both supermassive black holes once served as the centers of their respective galaxies, but a galactic merger brought the two objects much closer together. Eventually, their close spiral will result in a merger in about 100 million years, according to NASA, causing an energetic release of gravitational waves, or ripples in the fabric of space and time.
Such gravitational waves created by the collisions of supermassive black holes could be detected in the future by LISA, the European Space Agency-led Laser Interferometer Space Antenna mission that’s expected to launch in the mid-2030s.
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Israel will say it had no choice, but its airstrikes in Lebanon risks igniting a regional war
Israel carried out "pre-emptive" strikes against Hezbollah overnight, while the militant group says it has completed the "first phase" of an attack on 11 Israeli military sites.
This appears to have been a high-stakes Israeli military operation that risked igniting a regional war.
Israel will say it had no choice: One of the pillars of Israeli military doctrine has long been the principle that offence is the best form of defence.
It is not the first time it has used its air force hoping to defang an imminent threat. Israel insists it sent an armada of warplanes to the skies over Lebanon, more than a hundred strong, to stop an 'extensive planned attack involving thousands of rocket launches' about to be let loose by Hezbollah.
Just as Israel launched audacious air attacks obliterating Egyptian leader Gamal Abdel Nasser's air force in 1967 and Saddam Hussein's atomic programme in 1981, Israel says it despatched jets overnight to neutralise Hezbollah.
It is not clear how many enemy drones and missiles were already in the air. Hezbollah claims all 11 of its targets in Israel were hit and it launched 320 Katyusha rockets.
The primary strike it says was aimed at "a qualitative Israeli military target that will be announced later" as well as "enemy sites and barracks and Iron Dome [missile defence] platforms".
Israeli intelligence sources had claimed the airbase used in the strike on Shukr and the headquarters of Unit 8200, the Israeli military intelligence agency, north of Tel Aviv, were on Hezbollah's target list.
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Hezbollah meanwhile says Israel's operation failed to pre-empt its long-awaited retaliation and insists it succeeded in striking targets deep within Israel.
Two questions for now: Hezbollah's next move and what this does to efforts to end the war in Gaza.
Will Hezbollah draw a line under the Shukr/Haniyeh affair? The organisation says today's action is over but is more planned in the coming days? All eyes are on its commander Hassan Nasrallah who will address his faithful by video link tonight.
He has not been seen in public since Hezbollah's war with Israel in 2006 for fear of being assassinated by Israeli jets himself.
Hezbollah attacked Israel in the wake of Hamas atrocities on 7 October and has been locked in an almost daily artillery duel with Israel over their border ever since.
Israeli intelligence claims Hezbollah has amassed an arsenal of 150,000 missiles secreted in the hills of southern Lebanon since 2006, 10 times the amount it possessed back then.
It has so far refrained from unleashing that firepower: Analysts believe its paymasters and patrons in Tehran prefer to keep that armoury in reserve as an insurance policy for the day Israel may attack Iran itself, as well as its alleged nuclear programme.
But Israel has been testing that theory for months now, responding with force to Hezbollah's attacks in the north. Each exchange of fire has the potential to escalate the region into a wider war through miscalculation and unintended mass civilian casualties.
So far, events overnight do not seem to have upended the fragile efforts towards a ceasefire in Gaza. Delegations are still on their way to Cairo for the next round of talks. If anything the escalation reemphasises the urgency behind the diplomacy.
But it could also offer the Israelis a distraction, should they want one, from huge pressure from the US to make the concessions required to reach a deal.
Most Israeli observers believe Israel's Prime Minister Benjamin Netanyahu does not want a ceasefire on the terms currently being negotiated for fear it could lead to his coalition government falling apart.
But US, Qatari and Egyptian mediators insist the truce terms are the best and possibly last chance of bringing home Israel's hostages and ending the war.
They also believe a ceasefire in Gaza is the best way of reducing tensions in the north - which have exploded overnight so spectacularly.
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in 1961, Ranger 1, the first mission in the Ranger program, launched from Cape Canaveral Air Force Station.
#OTD in 1961, Ranger 1, the first mission in the Ranger program, launched from Cape Canaveral Air Force Station. A rocket malfunction during launch caused the spacecraft to get stranded in low-Earth orbit. Read More...
