•   
  •   

Tech & Science Quasars Can Trigger Tsunamis That Tear Across Galaxies And Snuff Out Star Formation

16:25  26 march  2020
16:25  26 march  2020 Source:   sciencealert.com

NASA just shut down the pioneering space telescope Spitzer

  NASA just shut down the pioneering space telescope Spitzer After almost 17 years of staring into space, NASA has said good night to Spitzer.The Spitzer space telescope, a bullet-shaped infrared eye that allowed scientists to peer at the edges of the cosmos for almost 17 years, has been taken offline. NASA announced the safe mode command had been sent to Spitzer at 1:56 p.m. PT on Thursday, turning off the telescope's systems.

It's well known that quasars are the most luminous galaxies in the Universe, spewing insane amounts of radiation across space as their supermassive black Astronomers have discovered that blasts of radiation emanating from quasars can act like a tsunami as they spread through the surrounding

These come from quasars that tear across Space like tsunamis — hence why they are sometimes referred to as " tsunami quasars ." Such high speeds are what may be tearing up the galaxies that host these quasars . These findings could help researchers answer the long-standing question about

a star filled sky © NASA, ESA, and J. Olmsted/STScI

It's well known that quasars are the most luminous galaxies in the Universe, spewing insane amounts of radiation across space as their supermassive black holes rapaciously devour material from a colossal accretion disc.

Well, they just got even more hardcore. Astronomers have discovered that blasts of radiation emanating from quasars can act like a tsunami as they spread through the surrounding galaxy, pushing material outward at velocities approaching a few percent of light speed. 

Such blasts of radiation are already known to move particles to a fraction of the speed of light, but these new discoveries take it to another level, with some of the fastest jumps in velocity seen to date.

REVEALED: Manchester United target Kalidou Koulibaly has £127m release clause in Napoli contract that will be active from JUNE this year

  REVEALED: Manchester United target Kalidou Koulibaly has £127m release clause in Napoli contract that will be active from JUNE this year Manchester United will have to meet Kalidou Koulibaly's £127million release clause, which becomes active in June, to snap up the highly-coveted Napoli defender.  The Old Trafford giants reportedly failed in a bid to sign the 28-year-old centre back, but could reignite their interest in the summer and trigger Koulibaly's clause.Both Corriere dello Sport and Corriere del Mezzogiorno highlighted the valuation United would have to match to sign the Senegalese international.

They emanate from quasars and tear across interstellar space like tsunamis , wreaking havoc on the galaxies in which the quasars live. “Both theoreticians and observers have known for decades that there is some physical process that shuts off star formation in massive galaxies , but the nature of

Some quasars act like tsunamis , pushing 46-million-MPH winds that blast out hundreds of times the Sun's weight of material per year while creating ripples across entire They also heat the materials around them, creating superheated disks that blast out "winds" via magnetic and radiation pressure.

What's more, as they blast through the material in their home galaxies, they quench the formation of new stars.

"These outflows are crucial for the understanding of galaxies' formation," said astrophysicist Nahum Arav of Virginia Tech.

"They are pushing hundreds of solar masses of material each year. The amount of mechanical energy that these outflows carry is up to several hundreds of times higher than the luminosity of the entire Milky Way galaxy."

The quasar stage of a galaxy's life is usually very early on – a period of intense activity that lasts up to a few billion years before the black hole settles down into a more conventional adulthood, having consumed or blown away all the nearby matter.

We know that this black hole activity generates powerful winds that blow into the surrounding space. We also know that the cold gas in this space is the stuff from which stars are formed. It's thought that when the black hole wind pushes it away, since there's nothing left to form stars, star formation is quenched.

Astronomers Have Detected Molecular Oxygen in Another Galaxy For The First Time

  Astronomers Have Detected Molecular Oxygen in Another Galaxy For The First Time In a wild galaxy over half a billion light-years away, astronomers have detected molecular oxygen. It's only the third such detection ever outside the Solar System - and the first outside the Milky Way. Oxygen is the third most abundant element in the Universe, behind hydrogen (naturally) and helium. So its chemistry and abundance in interstellar clouds are important for understanding the role of molecular gas in galaxies.

Yesterday we ran an article about galaxies colliding and forming fireballs. Today, there’s more evidence for galactic collisions, and it’s not good news for potential stars . Low-velocity collisions, especially between small- to medium-sized galaxies , often cause an increase in the local star formation rate

NASA discovers powerful quasar tsunamis . NOW PLAYING: Science. NASA discovers quasar tsunamis ripping across galaxies . GeoBeats. The 'Tarantula Nebula' shows the birth of massive stars .

This is consistent with what we have observed in older galaxies, which are much quieter than those hosting quasars; in fact, exactly how star formation is quenched is a puzzle astronomers have been trying to solve for a long time, since without it, the Universe would probably look very different from the one we see, with bigger galaxies and considerably more stars.

It's possible there are multiple mechanisms that can explain this ongoing puzzle.

"Both theoreticians and observers have known for decades that there is some physical process that shuts off star formation in massive galaxies, but the nature of that process has been a mystery," explained cosmologist Jeremiah Ostriker of Columbia University and Princeton University.

"Putting the observed outflows into our simulations solves these outstanding problems in galactic evolution."

Arav and his team studied Hubble observations of 13 known quasars to look for outflows. As these quasar tsunamis collide with interstellar gas, the collision generates intense heat, the energy of which is emitted in the form of light across the electromagnetic spectrum.

Toronto Wolfpack part ways with Noble

  Toronto Wolfpack part ways with Noble Super League newcomers Toronto Wolfpack have parted company with director of rugby Brian Noble just a month into the season. Noble, 59, has been with the Wolfpack since their formation in 2016 and has been largely responsible for recruitment of players and coaches and managing day-to-day activities as they progressed through the two tiers of the professional game.But the former Great Britain coach says it is now time to move on.

The outflows “ tear across interstellar space like tsunamis , wreaking havoc on the galaxies in which the quasars live,” said NASA, in a statement. An illustration of a distant galaxy with an active quasar at its center.

Meanwhile, astronomers were able to spot quasar tsunamis with the help of the Hubble Space While the first event captured the birth of stars , the quasar tsunamis disrupt their formation . They were able to discover the most powerful quasar tsunami as well as the outflow that accelerates much

"You'll get lots of radiation first in X-rays and gamma rays, and afterwards it will percolate to visible and infrared light," Arav said. "You'd get a huge light show, like Christmas trees all over the galaxy."

From this data, they were able to measure the three most energetic quasar outflows seen to date, found in quasar galaxies SDSS J1042+1646, SDSS J0755+2306, and 2MASS J1051+1247. All three were powerful enough to produce the feedback required for galactic quenching.

Among these, SDSS J1042+1646 was a record-breaker, exhibiting the most rapidly accelerating outflow. In a three-year period, one of its outflows accelerated from 70 million kilometres per hour (43 million mph) to 74 million kilometres per hour (46 million mph).

This research doesn't just show how galaxies can be quenched, though. It could also be a very neat explanation for why the size of most galaxies correlates with the size of their black hole.

If the black hole is blowing material away, it's not just limiting how many stars can form; it's also limiting the material it can feed on, and therefore how big it can grow.

"Hubble's ultraviolet observations allow us to follow the whole range of energy output from quasars, from cooler gas to the extremely hot, highly ionised gas in the more massive winds," said astronomer Gerard Kriss of the Space Telescope Science Institute.

"These were previously only visible with much more difficult X-ray observations. Such powerful outflows may yield new insights into the link between the growth of a central supermassive black hole and the development of its entire host galaxy."

The research has been published in six papers in The Astrophysical Journal Supplement Series.

Hubble telescope snaps dazzling pink cloud full of big baby stars .
Hubble telescope snaps dazzling pink cloud full of big baby starsSay hello to the Hubble Space Telescope's view of LHA 120-N 150. It's a cloud of dust and gas surrounded by stars, and it calls the suburbs of the Tarantula Nebula its home. The nebula is known as a hot spot for star formation, and this particular region is helping astronomers learn more about how massive stars are created.

—   Share news in the SOC. Networks

Topical videos:

usr: 0
This is interesting!