Connect with us

Science

Supermassive black holes may create the largest 'tsunamis' in the universe – CTV News

Published

 on


TORONTO —
When an earthquake happens underwater on Earth, it can create a tsunami – a ripple effect of gigantic proportions.

Now, a new study says that out in space, supermassive black holes may create tsunami-like structures.

The NASA-funded study was published on June 15 in the Astrophysical Journal. Researchers used computer simulations to model the environment of a supermassive black hole and found that tsunami-like structures​ can form through gas escaping the black hole’s gravitational pull.

NASA says these structures may be the largest tsunami-like structures in the universe.

A supermassive black hole has a mass that is greater than the mass of a million suns, and is considered the largest category of black holes. These black holes feed off matter and gases that swirl around them, forming a system that astrophysicists call the “active galactic nucleus.”

Strong winds driven by X-ray radiation from the centre of the nucleus create what astrophysics call an “outflow,” pushing matter out of the centre. Within the outflow, the X-rays can produce gas clouds around the black hole.

“These clouds are ten times hotter than the surface of the Sun and moving at the speed of the solar wind, so they are rather exotic objects that you would not want an airplane to fly through,” said lead author Tim Waters in a news release from NASA.

During the simulations, Waters and his team have found that these clouds can form into waves as the black hole loses grip on the matter. These waves can further spiral into vortex structures that are 10 light-years away from the black hole as they interact with hot winds, NASA says.

The simulations also shows that X-ray from the plasma near the black hole inflates pockets of heated gas within the black hole’s atmosphere, allowing the hot plasma to rise like a balloon and meet the surrounding cooler gas clouds.

This allows the clouds to form a pattern that astrophysicists call a Kármán vortex street, resembling a tsunami structure.

Previous theories have suggested that the clouds form spontaneously through fluid instability or that magnetic fields were involved in propelling cooler gas into the wind.

“While it all makes sense in hindsight, it was initially quite confusing to observe that thermal instability cannot produce cold gas directly, yet it can take the place of magnetic fields by lifting cold gas into the wind,” said Waters.

NASA says these findings have yet to be observed by satellites, but plasma near active galactic nuclei within these black holes have been observed by observatories on Earth at temperatures and speeds consistent with the simulations.​

Adblock test (Why?)



Source link

Continue Reading

Science

See A Jaw-Dropping Crescent Moon, 50 Meteors And Hour And Our Billion-Star Milky Way: What You Can See In The Night Sky This Week – Forbes

Published

 on


Each Monday I pick out the northern hemisphere’s celestial highlights (mid-northern latitudes) for the week ahead, but be sure to check my main feed for more in-depth articles on stargazing, astronomy, eclipses and more.

What To See In The Night Sky This Week: June 27-July 3, 2022

It’s not easy going stargazing in summer at this time of year in the northern hemisphere. The nights are just so short. The best reason to stay up late and go somewhere dark is the sight of the spiral arms of our Milky Way galaxy arcing across the night sky. Look to the southeast and south for that this month—and this week in particular, which will be largely moonless.

When our satellite does emerge from its New Moon conjunction with the Sun expect lush views of a slender crescent Moon. Who said summer was no good for stargazing?

Monday, June 27, 2022: Boötids meteor shower and a crescent Moon meets Mercury

The June Boötids meteor shower—occasionally called the June Draconids or Boötid-Draconids meteor shower—runs annually between June 22 and July 2, but peaks in the early hours of June 27, 2020.

If you are out stargazing late tonight keep an eye out for the 50 or so “shooting stars” per hour expected. The shower’s radiant point—the apparent source of the shooting stars—is the constellation of Boötes.

If you’re still up before dawn you might just catch the planet Mercury just 3.9º from an incredibly slender 2.6% crescent Moon, but be very careful if you use binoculars to help you because the rising Sun is NOT something you want in your field of view.

Tuesday, June 30, 2022: A super-slim crescent Moon and ‘Asteroid Day’

Today is Asteroid Day. With any luck there won’t be anything to see hurtling towards (or even smashing into) our planet, but it’s a good chance to consider the threat posed to Earth of incoming space rocks. What’s really going to change everything is the Vera Rubin Observatory, which from 2022 will deploy a wide-angle camera to map the night sky in real-time—and identify many thousands of hitherto unfound asteroids.

Friday, July 1, 2022: ‘Earthshine’ on a crescent Moon

You should get a much clearer view of a crescent Moon today. Now 8% illuminated, in a clear sky it will be a stunning sight, not least because you’ll be able to see sunlight being reflected onto the Moon by the Earth as “Earthshine” or “planet-shine.” It’s a subtle sight, but once seen cannot be unseen; look at the Moon’s darkened limb with your eyes, or better still, with a pair of binoculars, to appreciate this fine sight.

As a bonus it will be just 3.5° from the Beehive Cluster, though you’ll need a pair of binoculars to see its 30 or so easily visible stars.

Saturday, July 2, 2022: ‘Earthshine’ on a crescent Moon and Regulus

Tonight just after sunset look west for a 14% crescent Moon, once again displaying Earthshine. The stars around it will be those of the “sickle” in the constellation of Leo. The brightest, about 5º left of the Moon, will be Leo’s brightest star, Regulus. It’s one of the brightest stars in the night sky and about 78 light-years distant.

Object of the week: noctilucent clouds

This time of year the twilight seems to last forever at northerly latitudes so consider looking for a “ghostly” display of noctilucent or “night shining” clouds (NLCs). At their best in northern twilight skies during June and July (at latitudes between 50° and 70° north and south of the equator), NLCs are very delicate high altitude clouds of icy dust that form about 50 miles/80 kilometres up. Because the Sun is never too far below the horizon at these latitudes they get subtly lit up for a short time. They’re best seen with the naked eye or a pair of binoculars.

Wishing you clear skies and wide eyes.

Adblock test (Why?)



Source link

Continue Reading

Science

Astronomers Found a Crater From The Mystery Rocket That Smashed Into The Moon – ScienceAlert

Published

 on


The Lunar Reconnaissance Orbiter (LRO) – NASA’s eye-in-the-sky in orbit around the Moon – has found the crash site of the mystery rocket booster that slammed into the far side of the Moon back on 4 March 2022.

The LRO images, taken May 25th, revealed not just a single crater, but a double crater formed by the rocket’s impact, posing a new mystery for astronomers to unravel.

Why a double crater? While somewhat unusual – none of the Apollo S-IVBs that hit the Moon created double craters – they’re not impossible to create, especially if an object hits at a low angle. But that doesn’t seem to be the case here.

Astronomer Bill Gray, who first discovered the object and predicted its lunar demise back in January, explains that the booster “came in at about 15 degrees from vertical. So that’s not the explanation for this one.”

The impact site consists of an 18-meter-wide eastern crater superimposed on a 16-meter-wide western crater. Mark Robinson, Principal Investigator of the LRO Camera team, proposes that this double crater formation might result from an object with distinct, large masses at each end.

Before (2022-02-28) and after image (2022-05-21) of the Moon. (NASA/GSFC/Arizona State University)

“Typically a spent rocket has mass concentrated at the motor end; the rest of the rocket stage mainly consists of an empty fuel tank. Since the origin of the rocket body remains uncertain, the double nature of the crater may help to indicate its identity,” he said.

So what is it?

It’s a long story. The unidentified rocket first came to astronomers’ attention earlier this year when it was identified as a SpaceX upper stage, which had launched NASA’s Deep Space Climate Observatory (DSCOVR) to the Sun-Earth L1 Lagrange Point in 2015.

Gray, who designs software that tracks space debris, was alerted to the object when his software pinged an error. He told The Washington Post on January 26 that “my software complained because it couldn’t project the orbit past March 4, and it couldn’t do it because the rocket had hit the Moon.”

Gray spread the word, and the story made the rounds in late January – but a few weeks later, he received an email from Jon Giorgini at the Jet Propulsion Lab (JPL).

Giorgini pointed out that DSCOVR’s trajectory shouldn’t have taken the booster anywhere near the Moon. In an effort to reconcile the conflicting trajectories, Gray began to dig back into his data, where he discovered that he had misidentified the DSCOVR booster way back in 2015.

SpaceX wasn’t the culprit after all. But there was definitely still an object hurtling towards the Moon. So what was it?

A bit of detective work led Gray to determine it was actually the upper stage of China’s Chang’e 5-T1 mission, a 2014 technology demonstration mission that lay the groundwork for Chang’e 5, which successfully returned a lunar sample to Earth in 2020 (incidentally, China recently announced it would follow up this sample return mission with a more ambitious Mars sample return project later this decade). 

Jonathan McDowell offered some corroborating evidence that seemed to bolster this new theory for the object’s identity.

The mystery was solved.

Except, days later, China’s Foreign Minister claimed it was not their booster: it had deorbited and crashed into the ocean shortly after launch.

As it stands now, Gray remains convinced it was the Change 5-T1 booster that hit the Moon, proposing that the Foreign Minister made an honest mistake, confusing Chang’e 5-T1 with the similarly named Chang’e 5 (whose booster did indeed sink into the ocean).

As for the new double crater on the Moon, the fact that the LRO team was able to find the impact site so quickly is an impressive feat in itself. It was discovered mere months after impact, with a little help from Gray and JPL, who each independently narrowed the search area down to a few dozen kilometers.

For comparison, The Apollo 16 S-IVB impact site took more than six years of careful searching to find.

Bill Gray’s account of the booster identification saga is here, as well as his take on the double crater impact. The LRO images can be found here.

This article was originally published by Universe Today. Read the original article.

Adblock test (Why?)



Source link

Continue Reading

Science

New Zealand Says It's Set to 'Star' in NASA's Return to the Moon – BNN

Published

 on


(Bloomberg) — New Zealand is trumpeting its role in a plan to return humans to the Moon, saying it is set to star in NASA’s Capstone mission that will test the orbit for a lunar space station.

Rocket Lab has announced it will launch a satellite from Mahia, New Zealand, to test the lunar orbit for Gateway, a planned Moon-orbiting outpost that will provide astronauts with access to the lunar surface. Separately, New Zealand’s government said Monday it has signed an agreement with NASA to conduct new research to track spacecraft approaching and orbiting the Moon.

“The New Zealand space sector is set to star in NASA’s Capstone Moon mission,” said Andrew Johnson, manager of the New Zealand Space Agency. Launching into lunar orbit from New Zealand is “a significant milestone,” while the new research “will be increasingly important as more countries and private actors send spacecraft to the Moon,” he said.

NASA’s Artemis Program plans to return humans to the lunar surface as early as 2025, renewing human exploration of the Moon and progressing toward the exploration of Mars. It plans to land the first woman and first person of color on the Moon and explore more of the lunar surface than ever before.

Rocket Lab said it could launch the CubeSat satellite as soon as Tuesday, with the launch window open through July 27.  

New Zealand’s agreement with NASA will see a University of Canterbury-led research team, which includes contributors from the University of Auckland and the University of New South Wales in Australia, attempt to track spacecraft from observatories in Tekapo and Canberra. 

The scientists intend to validate their observations and algorithms to predict spacecraft trajectories enroute to the Moon and within their lunar orbits against NASA’s Capstone mission data.

©2022 Bloomberg L.P.

Adblock test (Why?)



Source link

Continue Reading

Trending