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Hubble spots double quasars in merging galaxies – Phys.org

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This artist’s conception shows the brilliant light of two quasars residing in the cores of two galaxies that are in the chaotic process of merging. The gravitational tug-of-war between the two galaxies stretches them, forming long tidal tails and igniting a firestorm of starbirth. Quasars are brilliant beacons of intense light from the centers of distant galaxies. They are powered by supermassive black holes voraciously feeding on infalling matter. This feeding frenzy unleashes a torrent of radiation that can outshine the collective light of billions of stars in the host galaxy. In a few tens of millions of years, the black holes and their galaxies will merge, and so will the quasar pair, forming an even more massive black hole. A similar sequence of events will happen a few billion years from now when our Milky Way galaxy merges with the neighboring Andromeda galaxy. Credit: NASA, ESA, and J. Olmsted (STScI)

NASA’s Hubble Space Telescope is “seeing double.” Peering back 10 billion years into the universe’s past, Hubble astronomers found a pair of quasars that are so close to each other they look like a single object in ground-based telescopic photos, but not in Hubble’s crisp view.

The researchers believe the quasars are very close to each other because they reside in the cores of two merging . The team went on to win the “daily double” by finding yet another quasar pair in another colliding galaxy duo.

A quasar is a brilliant beacon of intense light from the center of a distant galaxy that can outshine the entire galaxy. It is powered by a supermassive black hole voraciously feeding on inflating matter, unleashing a torrent of radiation.

“We estimate that in the distant universe, for every 1,000 quasars, there is one double quasar. So finding these double quasars is like finding a needle in a haystack,” said lead researcher Yue Shen of the University of Illinois at Urbana-Champaign.

The discovery of these four quasars offers a new way to probe collisions among galaxies and the merging of supermassive black holes in the early universe, researchers say.

Quasars are scattered all across the sky and were most abundant 10 billion years ago. There were a lot of galaxy mergers back then feeding the black holes. Therefore, astronomers theorize there should have been many dual quasars during that time.

“This truly is the first sample of dual quasars at the peak epoch of galaxy formation with which we can use to probe ideas about how supermassive black holes come together to eventually form a binary,” said research team member Nadia Zakamska of Johns Hopkins University in Baltimore, Maryland.

The team’s results appeared in the April 1 online issue of the journal Nature Astronomy.

Shen and Zakamska are members of a team that is using Hubble, the European Space Agency’s Gaia space observatory, and the Sloan Digital Sky Survey, as well as several ground-based telescopes, to compile a robust census of quasar pairs in the early universe.

Hubble spots double quasars in merging galaxies
These two Hubble Space Telescope images reveal two pairs of quasars that existed 10 billion years ago and reside at the hearts of merging galaxies. Each of the four quasars resides in a host galaxy. These galaxies, however, cannot be seen because they are too faint, even for Hubble. The quasars within each pair are only about 10,000 light-years apart — the closest ever seen at this cosmic epoch. Quasars are brilliant beacons of intense light from the centers of distant galaxies that can outshine their entire galaxies. They are powered by supermassive black holes voraciously feeding on infalling matter, unleashing a torrent of radiation. The quasar pair in the left-hand image is catalogued as J0749+2255 and the pair on the right as J0841+4825. The two pairs of host galaxies inhabited by each double quasar will eventually merge. The quasars will then tightly orbit each other until they eventually spiral together and coalesce, resulting in an even more massive, but solitary black hole. The image for J0749+2255 was taken Jan. 5, 2020. The J0841+4825 snapshot was taken Nov. 30, 2019. Both images were taken in visible light with Wide Field Camera 3. Credit: NASA, ESA, H. Hwang and N. Zakamska (Johns Hopkins University), and Y. Shen (University of Illinois, Urbana-Champaign)

The observations are important because a quasar’s role in galactic encounters plays a critical part in galaxy formation, the researchers say. As two close galaxies begin to distort each other gravitationally, their interaction funnels material into their respective black holes, igniting their quasars.

Over time, radiation from these high-intensity “light bulbs” launch powerful galactic winds, which sweep out most of the gas from the merging galaxies. Deprived of gas, star formation ceases, and the galaxies evolve into elliptical galaxies.

“Quasars make a profound impact on galaxy formation in the universe,” Zakamska said. “Finding dual quasars at this early epoch is important because we can now test our long-standing ideas of how black holes and their host galaxies evolve together.”

Astronomers have discovered more than 100 double quasars in merging galaxies so far. However, none of them is as old as the two double quasars in this study.

The Hubble images show that quasars within each pair are only about 10,000 light-years apart. By comparison, our Sun is 26,000 light-years from the in the center of our galaxy.

The pairs of host galaxies will eventually merge, and then the quasars also will coalesce, resulting in an even more massive, single solitary black hole.

Finding them wasn’t easy. Hubble is the only telescope with vision sharp enough to peer back to the and distinguish two close quasars that are so far away from Earth. However, Hubble’s sharp resolution alone isn’t good enough to find these dual light beacons.

Astronomers first needed to figure out where to point Hubble to study them. The challenge is that the sky is blanketed with a tapestry of ancient quasars that flared to life 10 billion years ago, only a tiny fraction of which are dual. It took an imaginative and innovative technique that required the help of the European Space Agency’s Gaia satellite and the ground-based Sloan Digital Sky Survey to compile a group of potential candidates for Hubble to observe.

Located at Apache Point Observatory in New Mexico, the Sloan telescope produces three-dimensional maps of objects throughout the sky. The team pored through the Sloan survey to identify the quasars to study more closely.

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The researchers then enlisted the Gaia observatory to help pinpoint potential double-quasar candidates. Gaia measures the positions, distances, and motions of nearby celestial objects very precisely. But the team devised a new, innovative application for Gaia that could be used for exploring the distant universe. They used the observatory’s database to search for quasars that mimic the apparent motion of nearby stars. The quasars appear as single objects in the Gaia data. However, Gaia can pick up a subtle, unexpected “jiggle” in the apparent position of some of the quasars it observes.

The quasars aren’t moving through space in any measurable way, but instead their jiggle could be evidence of random fluctuations of light as each member of the quasar pair varies in brightness. Quasars flicker in brightness on timescales of days to months, depending on their black hole’s feeding schedule.

This alternating brightness between the quasar pair is similar to seeing a railroad crossing signal from a distance. As the lights on both sides of the stationary signal alternately flash, the sign gives the illusion of “jiggling.”

When the first four targets were observed with Hubble, its crisp vision revealed that two of the targets are two close pairs of quasars. The researchers said it was a “light bulb moment” that verified their plan of using Sloan, Gaia, and Hubble to hunt for the ancient, elusive double powerhouses.

Team member Xin Liu of the University of Illinois at Urbana-Champaign called the Hubble confirmation a “happy surprise.” She has long hunted for double quasars closer to Earth using different techniques with ground-based telescopes. “The new technique can not only discover dual quasars much further away, but it is much more efficient than the methods we’ve used before,” she said.

Their Nature Astronomy article is a “proof of concept that really demonstrates that our targeted search for dual quasars is very efficient,” said team member Hsiang-Chih Hwang, a graduate student at Johns Hopkins University and the principal investigator of the Hubble program. “It opens a new direction where we can accumulate a lot more interesting systems to follow up, which astronomers weren’t able to do with previous techniques or datasets.”

The team also obtained follow-up observations with the National Science Foundation NOIRLab’s Gemini telescopes. “Gemini’s spatially-resolved spectroscopy can unambiguously reject interlopers due to chance superpositions from unassociated star-quasar systems, where the foreground star is coincidentally aligned with the background quasar,” said team member Yu-Ching Chen, a graduate student at the University of Illinois at Urbana-Champaign.

Although the team is convinced of their result, they say there is a slight chance that the Hubble snapshots captured double images of the same quasar, an illusion caused by gravitational lensing. This phenomenon occurs when the gravity of a massive foreground galaxy splits and amplifies the light from the background quasar into two mirror images. However, the researchers think this scenario is highly unlikely because Hubble did not detect any foreground galaxies near the two quasar pairs.

Galactic mergers were more plentiful billions of years ago, but a few are still happening today. One example is NGC 6240, a nearby system of merging galaxies that has two and possibly even three supermassive black holes. An even closer galactic merger will occur in a few billion years when our Milky Way galaxy collides with neighboring Andromeda galaxy. The galactic tussle would likely feed the supermassive black holes in the core of each galaxy, igniting them as quasars.

Future telescopes may offer more insight into these merging systems. NASA’s James Webb Space Telescope, an infrared observatory scheduled to launch later this year, will probe the quasars’ host galaxies. Webb will show the signatures of galactic mergers, such as the distribution of starlight and the long streamers of gas pulled from the interacting galaxies.


Explore further

Maunakea observatories discover three pairs of merging supermassive black holes


More information:
Yue Shen et al. A hidden population of high-redshift double quasars unveiled by astrometry, Nature Astronomy (2021). DOI: 10.1038/s41550-021-01323-1

Citation:
Hubble spots double quasars in merging galaxies (2021, April 6)
retrieved 6 April 2021
from https://phys.org/news/2021-04-hubble-quasars-merging-galaxies.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.

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SpaceX launches amateur crew on private Earth-circling trip – Al Jazeera English

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SpaceX’s first private flight has been launched into orbit with two contest winners, a healthcare worker and their rich sponsor on board, the most ambitious leap yet in space tourism.

The launch on Wednesday night was the first time a spacecraft circled Earth with an all-amateur crew and no professional astronauts.

“Punch it, SpaceX!” the flight’s billionaire leader, Jared Isaacman, urged moments before liftoff.

The Dragon capsule’s two men and two women are looking to spend three days circling the planet from an unusually high orbit – 160km (100 miles) higher than the International Space Station – before splashing down off the Florida coast this weekend.

It is SpaceX founder Elon Musk’s first entry in the competition for space tourism dollars.

Isaacman is the third billionaire to launch this summer, following the brief space-skimming flights by Virgin Galactic’s Richard Branson and Blue Origin’s Jeff Bezos in July. Only 38, Isaacman made his fortune from a payment-processing company he started in his teens.

Joining Isaacman on the trip dubbed Inspiration4 is Hayley Arceneaux, 29, a childhood bone cancer survivor who works as a physician assistant where she was treated – St Jude Children’s Research Hospital in Memphis, Tennessee. Isaacman has pledged $100m out of his own pocket to the hospital and is seeking another $100m in donations.

Arceneaux became the youngest American in space and the first person in space with a prosthesis, a titanium rod in her left leg.

Also along for the ride are sweepstakes winners Chris Sembroski, 42, a data engineer in Everett, Washington, and Sian Proctor, 51, a community college educator in Tempe, Arizona.

Once opposed to space tourism, NASA is now a supporter.

“Low-Earth orbit is now more accessible for more people to experience the wonders of space,” tweeted NASA Administrator Bill Nelson, who was a congressman when he hitched a ride on a space shuttle decades ago.

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Researchers create a novel method of bioprinting neuron cells – Medical Xpress

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Credit: Public Domain

A group of researchers including a Concordia Ph.D. student have developed a new method of bioprinting adult neuron cells. They’re using a new laser-assisted technology that maintains high levels of cell viability and functionality.

Ph.D. candidate and 2020-21 Public Scholar Hamid Orimi and his co-authors present the feasibility of a new bioprinting technology they developed in a recent paper published in the journal Micromachines. They demonstrate how the methodology they created, called Laser-Induced Side Transfer (LIST), improves on existing bioprinting techniques by using bioinks of differing viscosities, allowing for better 3D printing. Orimi, his Concordia co-supervisor Sivakumar Narayanswamy in the Gina Cody School of Engineering and Computer Science, CRHMR co-supervisor Christos Boutopoulos and co-authors at the Université de Montréal first presented the method in the Nature journal Scientific Reports in 2020.

Orimi co-wrote the newer paper with lead author Katiane Roversi, Sebastien Talbot and Boutopoulos at UdeM and Marcelo Falchetti and Edroaldo da Rocha at Federal University of Santa Catarina in Brazil. In it, the researchers demonstrate that the technology can be used to successfully print sensory , a vital component of the peripheral nervous system. This, they say, is promising for the long-term development of bioprinting’s potential, including disease modeling, and implant fabrication.

Viable and functional

The researchers used dorsal root ganglion (DRG) neurons from the peripheral nervous system of mice to test their technology. The neurons were suspended in a bioink solution and loaded into a square capillary above a biocompatible substrate. Low-energy nanosecond laser pulses were focused on the middle of the capillary, generating microbubbles that expanded and ejected a cell-laden microjet onto the substrate below it. The samples were briefly incubated, then washed and re-incubated for 48 hours.

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Credit: University of Montreal

The team then ran several tests to measure the printed cells’ capacities. A viability assay found that 86 percent of the cells remained alive two days after printing. The researchers note that viability rates improved when the laser used lower energy. The thermomechanics associated with higher laser energy use was more likely to damage the cells.

Other tests measured neurite outgrowth (in which developing neurons produce new projections as they grow in response to guidance cues), neuropeptide release, calcium imaging and RNA sequencing. Overall, the results were generally encouraging, suggesting that the technique could be an important contribution to the field of bioprinting.

Good for people and animals

“In general, people often leap to conclusions when we talk about bioprinting,” Orimi says. “They think that we can now print things like for transplants. While this is a long-term objective, we are very far from that point. But there are still many ways to use this technology.”

Nearest at hand is drug discovery. The team hopes to get approval to continue their research into cell grafting, which can assist greatly in drug discovery, such as for nerve recovery medicines.

Another advantage to using this technology, Orimi says, is a decrease in animal testing. This not only has a humanitarian aspect—fewer animals will be euthanized to carry out experiments meant to benefit humans—but it will also produce more accurate results, since testing will be carried out on human, not animal, tissue.


Explore further

FRESH 3-D-printing platform paves way for tissues, organs


More information:
Hamid Ebrahimi Orimi et al, Drop-on-demand cell bioprinting via Laser Induced Side Transfer (LIST), Scientific Reports (2020). DOI: 10.1038/s41598-020-66565-x

Citation:
Researchers create a novel method of bioprinting neuron cells (2021, September 15)
retrieved 15 September 2021
from https://medicalxpress.com/news/2021-09-method-bioprinting-neuron-cells.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.

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Josh Richards Is Bringing Back The Woolly Mammoth – Forbes

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Influencers are everywhere. 

They are at the MET Gala. They are walking the red carpet at the VMAs and now they are part of a team creating de-extinction technology which will bring the woolly mammoth back to the Arctic tundra within the next six years. 

Yes, you read that right. Extinction could be a thing of the past thanks to a TikToker and his friends.  

Josh Richards may be known to the masses as a TikTok star with over 40 million followers across social media but he has consistently proven to be a lot more than that. 

He has developed himself into a serial entrepreneur with companies ranging from Ani Energy, his energy drink which is now in Walmart, to Cross Check Studios, his production company with Mark Wahlberg, to Animal Capital, an $18 million venture capital fund that he started with his business partner Michael Gruen and former Goldman Sachs investment banker Marshall Sandman. 

This week, Richards and his fund Animal Capital announced their investment and advisory position into Colossal. They are a company that is using recent breakthrough advances in CRISPR genetic engineering, a new wave of disruptive conservation and restorative biology, which will eventually make extinction a thing of the past. 

The company was founded by tech entrepreneur Ben Lamm and world-renowned geneticist and serial biotech entrepreneur George Church, Ph.D. In addition to being a founder of Colossal, Church also serves as a Professor of Genetics at Harvard Medical School and is a Professor of Health Sciences and Technology at Harvard and MIT. 

Lamm said, “Genetic engineering holds an endless amount of opportunity for the future of humanity: From eradicating diseases to improving our ability to survive in changing climates. It is a breakthrough technology. As an entrepreneur, I’ve routinely found myself on the cusp of breakthrough technologies because I believe they mark powerful nexus events in the future of our species. I am incredibly excited and grateful for great partners and investors like Josh Richards and Animal Capital who see our long-term vision and can help contribute to the advancement of science and genomics.”  

Richards has been involved in the Animal Capital since its inception a year ago and his stamp is felt throughout the company. He, Gruen and Sandman brought on billionaire movie and technology mogul, Thomas Tull, to lead the round of funding. They brought Paramount Pictures President, Michael Ireland, and Billboard president, Julian Holguin, on as advisors. They got the billionaire Winklevoss twins to invest, as well as others. They’ve also been heavily involved in the company’s rollout and media strategy. 

Josh Richards said, “It is mind boggling that a 19-year-old kid from a small town in Ontario could be a part of a team that will change the world. To be involved in a company like this, that will change the world for the better, and allow my kids’ kids to have a better life, is truly an honor. My generation is the generation tasked with combatting climate change and creating a better world as we are the generation set to inherit the Earth.”

Sandman, the managing partner of Animal Capital, said, “The opportunity to invest in Colossal really speaks to the reason we originally started Animal Capital. Ben, George and the entire team are on a path to change the world and we are proud to be along for the journey”

Animal Capital’s other investments, include: Mental health technology, Whoop, crypto startup, WonderFi, which went public on the NEO two weeks ago and calendar-based social media platform, Saturn.

So, who knows, maybe we’ll see Josh Richards making a TikTok on a wooly mammoth. soon. Stay tuned.

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