Philae sleeps, but Rosetta's not done yet

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Its battery dead, the European lander is lost in a crater somewhere on a huge comet. But the orbiter that brought it there still has plenty of science left to do.



As of Saturday morning, the Philae lander is in a digital coma somewhere on the surface of comet 67P/Churyumov-Gerasimenko. But even if the history-making little robot never wakes again, the Rosetta mission and the orbiter of the same name still have a long journey ahead of them.

The plan was for Philae to land at a targeted site on the comet, firing harpoons into the surface of the icy rock to keep itself locked in place for a long trip around the sun. The strong grip was particularly important since a comet this size has only a tiny fraction of the gravity of a place like Earth, leaving little Philae at risk of floating off into space.

But when showtime came, there were problems with Philae's downward thrusters and with firing the harpoons. The European Space Agency reports that the lander bounced off the surface of the comet twice and eventually landed somewhere else without much access to the sunlight its solar panels need to keep it functioning.

Friday evening, Philae used its remaining energy to upload all its data before going into hibernation mode. There was a time slot early this morning during which, the ESA had reported, communication with the lander was possible, but that time has now come and gone.

Still, Rosetta remains.

Even if Philae stays lost in a comet crater for the next year, the orbiter that traveled almost half a billion miles to get to this point will continue to orbit the comet and its lost lander.

Right now, Rosetta has been pulling out to a 30 kilometer orbit of the comet. It will come closer again early next month to get more details on the comet -- some of its flybys will be as close as 8 kilometers to the comet. There's a whole lot of potential science and data about comets, planets and our solar system packed in that process, building up to the trio's closest encounter with the sun, next August.

Before that point there may also be better opportunities to rouse Philae.

https://www.youtube.com/watch?v=crbnOY8WeB8#t=15

10 Wonders Of The Universe

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What's the biggest thing in the universe? Find out here, along with 9 other incredible astronomical wonders.

http://www.youtube.com/watch?v=yUbQnHvXYEI

3D-printed engine parts future of space launches: NASA

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A team of NASA researchers has found that 3D manufactured copper parts could withstand the heat and pressure required of combustion engines used in space launches.

The US space agency and California-based rocket and missile propulsion manufacturer Aerojet Rocketdyne (AR) conducted 19 hot-fire tests on four injector and thrust chamber assembly configurations at NASA's Glenn Research Centre.

"The successful hot fire test of engine components provides confidence in the additive manufacturing process and paves the way for full-scale development," said Tyler Hickman, lead engineer for the test at Glenn.

3D printing approach is changing the speed, cost and flexibility of designing and building future machines for space and earth applications.

The work is a major milestone in the development and certification of different materials used in the manufacturing process.

Copper alloys offer unique challenges to the additive manufacturing processes.

"Additively manufactured metal propulsion components are truly a paradigm shift for the aerospace industry," added Paul Senick, Glenn project manager.

This will improve efficiency and bring down the cost of space launches and other earth applications, he concluded.

Source : business standard

A Universe of Blue Dots? --"Water Common During the Formation of All Planetary Systems"

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The new SciFi blockbuster, Interstellar, shows astonauts from post apocalyptic earth, destroyed by what appears to be a modern dust-bowl, catapulted into the unknown of outer space in the hopes of finding a new home for the human race, only to discover an extraterrestrial tidal wave on a distant exo planet. How realistic is the premise of an alien water planet? New findings suggest it's based on solid science.
"This is an important step forward in our quest to find out if life exists on other planets," said Tim Harries, from the University of Exeter's Physics and Astronomy department, who was part of the research team. "We know that water is vital for the evolution of life on Earth, but it was possible that the Earth's water originated in the specific conditions of the early solar system, and that those circumstances might occur infrequently elsewhere. By identifying the ancient heritage of Earth's water, we can see that the way in which our solar system was formed will not be unique, and that exoplanets will form in environments with abundant water. Consequently, it raises the possibility that some exoplanets could house the right conditions, and water resources, for life to evolve."
The implication of these findings is that some of the solar system's water must have been inherited from the Sun's birth environment, and thus predate the Sun itself. If our solar system's formation was typical, this implies that water is a common ingredient during the formation of all planetary systems.

To date, the Kepler satellite has detected nearly 1,000 confirmed extrasolar planets. The widespread availability of water during the planet-formation process puts a promising outlook on the prevalence of life throughout the galaxy.

A pioneering new study has shown that water found on Earth predates the formation of the Sun – raising hopes that life could exist on exoplanets, the planets orbiting other stars in our galaxy. The ground-breaking research set out to discover the origin of the water that was deposited on the Earth as it formed.

It found that a significant fraction of water found on Earth, and across our solar system, predates the formation of the Sun. By showing that water is 'inherited' from the environment when a star is born, the international team of scientists believe other exoplanetary systems also had access to an abundance of water during their own formation.

As water is a key component for the development of life on Earth, the study has important implications for the potential for life elsewhere in the galaxy.

Scientists have previously been able to understand the conditions present when stars are formed by looking at the composition of comets and asteroids, which show which gases, dust and, most importantly, ices were circling the star at its birth.

The team of international scientists were able to use 'heavy water' ices – those with an excess of water made with the element deuterium rather than hydrogen – to determine whether the water ices formed before, or during, the solar system's formation.

The Rosetta comet landing has made history

http://i.telegraph.co.uk/multimedia/archive/02758/Rosetta_2758749b.jpg

After 10 years of hard work and one nerve-wracking night, the Rosetta mission has made history by landing on the surface of a comet.

The lander Philae was confirmed to touch down on the surface of the comet more than 300 million miles away at 11:03 a.m. Eastern. Now, scientists expect it to send a panoramic image home and begin analyzing the comet for scientists back on Earth.

Philae is already transmitting scientific data back home, but we're still waiting to see whether the probe is in a stable position. Until we know it's anchored tight, it could roll onto its back and never get back up.

Tensions were high in the European Space Agency's German mission control center, especially as the landing window approached. Because the comet that Philae landed on is so far from Earth, there's a communications delay of 28 minutes. So as the minutes ticked by, the Rosetta team knew that Philae had already either landed or failed — and there was nothing they could do but wait for the data to reach them. Those following the video online were nearly as desperate for news, and Twitter became a sounding chamber of anticipation and excitement.

But a few minutes after 11 a.m., the stern, cautious expressions of the mission control team melted into smiles. And just like that, the world swiveled from anxiety to elation: Philae was on the surface of the comet and ready to do some science.

The comet contains the materials that originally formed our solar system, frozen in time. By digging them out, we can learn more about the origins of our planet. The Rosetta spacecraft has made invaluable observations about the comet's attributes, and it will continue to do so as it follows it around the sun for the next year. But Philae will be able to look more closely at the comet's physical and molecular composition.

"It's a look at the basic building blocks of our solar system, the ancient materials from which life emerged," said Kathrin Altwegg of the University of Bern in Switzerland, one of the Rosetta project's lead researchers. "It's like doing archaeology, but instead of going back 1,000 years, we can go back 4.6 billion."

It's no easy thing to land on a comet's surface: These chunks of rock and ice are constantly spinning, and Comet 67P/Churyumov-Gerasimenko, which was discovered in 1969, orbits the sun at a speed of about 85,000 mph. It's irregularly shaped — like a toddler's play-dough impression of a duck, or something — and its surface is uneven and pitted. And in a universe of unimaginable proportion, Rosetta's target is just 2.5 miles in diameter — smaller than Northwest Washington's Columbia Heights neighborhood.

So Rosetta has taken an onerous journey to get in sync with the comet's orbit, which would allow it to drop down a lander. In 2004, the spacecraft began what would be three looping orbits around the sun, altering its trajectory as it skimmed Mars, just 150 miles from the surface, and enduring 24 minutes in the planet’s shadow to align with Churyumov-Gerasimenko. The cumulative distance traveled by the craft – with all its looping and gravity assists – is a stunning 4 billion miles. “When the Rosetta signal reappeared after the passage behind Mars, shortly after the end of the ‘shadow’ period, there was a collective sigh of relief,” ESA said.

At one point in 2011, the spacecraft even had to hibernate for nearly three years. It flew so far from the sun — nearly 500 million miles — that its solar panels couldn't leech enough energy to keep the spacecraft operational. But in January of this year, Rosetta woke up, and quickly approached its target.

The last leg of this landing has not been without its bumps. Even as the mission approached its most critical moment, controllers at the European Space Agency on Tuesday night reported a problem with the thruster on the lander that could make for a rough landing. The gravity of the problem — and the extent to which it threatened the mission — remained unknown. “We’ll need some luck not to land on a boulder or a steep slope,” blogged Stephan Ulamec, lander manager for the project.

Source : washington post

SpaceX will launch micro-satellites for low cost internet

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Elon Musk has confirmed that SpaceX is working on micro-satellites. Following a story in The Wall Street Journal, he tweeted this morning that SpaceX is developing “advanced micro-satellites operating in large formations” with an official announcement due in two to three months.

It said SpaceX is planning a launch of 700 satellites, each weighing less than 250 pounds. A fleet that size would be 10x bigger than the largest current deployment managed by  Iridium Communications.

Sorce : next web

ISS crew lands, brings space-born flies to Earth

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Three crew members of the International Space Station have safely returned to Earth aboard a Soyuz-13M spacecraft, bringing back good memories and results of their 165-day shift in orbit – including a space-born generation of experimental fruit flies.

The spacecraft carrying the commander of the ISS Expedition 41 Russian cosmonaut Maksim Surayev, as well as two flight engineers, NASA astronaut Reid Wiseman and ESA astronaut Alexander Gerst, landed some 80 km from Arkalyk, Kazakhstan.

As part of their mission, the crew completed some 2,640 orbits covering more than 70 million miles and have participated in a number of experiments, including breeding of fruit flies that could potentially shed light on long-term space flight effects on human beings.

Evidence of 'Starquakes' on Neutron Star

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An earthquake can be a pretty awe-inspiring natural event - a testament to the sheer power and size of shifting landmass. But what about seismic activity on a star? NASA's Fermi satellite recently spotted evidence of seismic waves rippling throughout a high-energy neutron star, resulting in an intense "storm" of high-energy blasts.

The star in question, called SGR J1550-5418, is a magnetar - an incredibly dense and highly magnetized neutron star that spins at an exceptionally high speed. The typical neutron star boasts a magnetic pull trillions of times stronger than the Earth's. A magnetar, by comparison, is about 1,000 times more magnetic than that.

Within the last four decades, only 23 magnetars in all have been identified, and among these stars, only three massive flares have ever been seen. The flares were related to "starquakes," in which instability of a neutron's pressing magnetic field literally shakes its surface.

"Fermi's Gamma-ray Burst Monitor (GBM) has captured the same evidence from smaller and much more frequent eruptions called bursts.

Source : nature world news

Mars bombarded by once-in-8-million-year meteor storm: NASA

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This handout artist's concept provided by NASA/JPL shows the Comet Siding Spring approaching Mars, shown with NASA’s orbiters preparing to make science observations of this unique encounter.

A pristine distant comet created a once-in-8-million-year fireworks show above Mars last month. But no one got to see it live.

New NASA data from satellites circling Mars shows that when the comet named Siding Spring skimmed the red planet, tons of comet dust bombarded the Martian sky with thousands of fireballs an hour. It warped the Martian atmosphere leaving all sorts of metals and an eerie yellow afterglow on Oct. 19.

A meteor shower from magnesium, sodium, iron and five other metals may have been so heavy that it might be even considered a meteor storm, said University of Colorado scientist Nick Schneider. Spikes in magnesium physically changed the atmosphere around Mars, while sodium left a yellowish glow in the sky after the meteor showers finished, he said.

“It would have been truly stunning to the human eye,” said Schneider, who was the lead instrument scientist for one of NASA’s Martian satellites. “It would have been really mind-blowing.”

The best view would have been from the Martian surface, where NASA had the rovers Opportunity and Curiosity looking up. But the rovers could only take stills, said agency chief planetary scientist Jim Green. There was no video to capture the shooting stars that made it a spectacular light show.

Instead, NASA’s satellites recorded lots of scientific data, which allowed astronomers to describe what it must have been like.

The core of the spinning comet moved by Mars at more than 125,000 mph and could have been as large as 1.2 miles wide, astronomers said.

It was not only big, but the dust assault was far larger than NASA anticipated, Green said. NASA’s models estimated that the dust wouldn’t be enough to harm the satellites around Mars, but the agency moved them to the other side of the planet just in case. That turned out to be wise, he said.

The comet came from the Oort Cloud, which is at the very edge of our solar system. Comets from there are rare so this was the type of event that happens once every 8 million years. And when they come toward the sun they aren’t as dusty as others, more pristine, astronomers said.

“We never before had the opportunity to observe an Oort Cloud comet up close,” Green said. “Instead of going to the comet, it came to us.”

Source: new york post

Is Earth the only technologically-intensive civilization in Universe?

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A new study has revealed that the combination of earth-based science of sustainability and the space-oriented field of astrobiology can shed light on the future of technological civilization on Earth and is the planet first and only technologically-intensive culture in Universe.
Human-caused climate change, ocean acidification and species extinctions may eventually threaten the collapse of civilization, according to some scientists, while other people argue that for political or economic reasons industrial development should be allowed without restrictions.

In the paper, two astrophysicists argue that these questions may soon be resolvable scientifically, thanks to new data about the Earth and about other planets in our galaxy, and by combining the earth-based science of sustainability with the space-oriented field of astrobiology .

Astrophysicists Adam Frank and Woodruff Sullivan call for creation of a new research program to answer questions about humanity's future in the broadest astronomical context.

The authors explained that the point would be to see that Earth's current situation might, in some sense, be natural or at least a natural and generic consequence of certain evolutionary pathways.

The researchers also showed that how habitability studies of exoplanets hold important lessons for sustaining the civilization we have developed on Earth.

According to the results, studying past extinction events and using theoretical tools to model the future evolutionary trajectory of humankind and of still unknown but plausible alien civilizations could inform decisions that would lead to a sustainable future.

Source : Zee news

Hubble spots massive 'eye in the sky'

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It might look like a giant eye in the sky, or something from a science fiction fiction film, but in fact this incredible image reveals just how violent planet formation is.

Captured by the Hubble Space Telescope, it shows the huge dusty debris discs around stars.

Created by collisions between leftover objects from planet formation, were imaged around stars as young as 10 million years old and as mature as more than 1 billion years old in Nasa's images.

The researchers discovered that no two "disks" of material surrounding stars look the same.

“We find that the systems are not simply flat with uniform surfaces,” Schneider said.

Source: dailymail

Half of universe's stars are orphans with no galaxy

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Celestial orphans are relatively small, less massive, cooler than our sun, expert says

New observations from suborbital rocket launches and an orbiting observatory show that as many as half the stars in the universe may be orphans with no galaxy scientists said on Thursday. They found that the dim light these stars produce from the far reaches of the cosmos equals the amount coming from all the galaxies.

'The night sky on a planet around such a star would be profoundly boring and black to human eyes - no other stars, or at least very few, no Milky Way band, only distant galaxies.'                                        - Michael Zemcov, Caltech experimental astrophysicist

The phenomenon of the orphan star has been well known. Astronomers have witnessed tidal streams of stars being stripped away from colliding pairs of galaxies.

The data suggests orphan stars are probably relatively small, less massive and cooler than our Sun, but typical of most stars in the universe, said Caltech experimental astrophysicist Michael Zemcov.

The night sky as seen from Earth is brimming with starlight. But these orphans would be so distant from other stars that a view from one would offer almost complete nothingness.

"The night sky on a planet around such a star would be profoundly boring and black to human eyes - no other stars, or at least very few, no Milky Way band, only distant galaxies. You might be lucky and see your parent galaxy off in the distance like we see Andromeda," Zemcov said.

Zemcov said scientists have traced the origin of galaxies to about 13.2 billion years ago, 500 million years after the Big Bang that created the universe.

"Galaxies have been forming and interacting continuously since then, with a peak in the star formation rate about two billion years after the Big Bang," Zemcov said. "You have enough interactions over enough time, and you end up stripping out a lot of stars."

Source : cbc.ca

ROSETTA SPACECRAFT SET TO LAND ON COMET CHURYUMOV-GERASIMENKO

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An artist’s impression of the Philae probe setting down on Comet Churyumov-Gerasimenko.

If you have an interest in space exploration, you could not have picked a better time in history to be alive than right now. Data and images stream back to Earth daily at an unprecedented rate from robotic spacecraft active at far-flung destinations all over the solar system. To use an old political quote – we’ve never had it so good.

In the past 50 years we’ve exploded out of our “little blue dot” to leave boot prints on the moon, land on Venus, Mars and Saturn’s moon Titan, and to orbit Mercury, Jupiter, Saturn, asteroids and comets, giving us incredible visual vistas of all.

What’s missing is a detailed view of dwarf planet Pluto, but we’ll have that when the New Horizons spacecraft gets there next year.

There’s also another missing first about to be achieved next week – we’re going to make a soft landing on the surface of a comet.

Comet Churyumov-Gerasimenko had to wait around patiently for billions of years for humans to discover it in 1967. However, it’s been a much shorter wait for an opportunity to get up close and personal with it – we’re landing a probe on the frozen dumbbell-shaped comet next Wednesday, November 12.

The Rosetta spacecraft, carrying the Philae probe, was launched  from French Guiana in February 2004 by the European Space Agency. It arrived in August this year and has already given us great views of the comet.

It was named for the Rosetta Stone found in Egypt that was crucial in deciphering ancient Egyptian hieroglyphics. Similarly the “lander” is named for the Nile River island Philae, where an obelisk also assisted in solving the puzzle of these symbols.

Milky Way's Supermassive Black Hole Reveals Identity of Strange Object at Center of Our Galaxy

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 What are Supermassive Black Hole ?

Supermassive black hole (SMBH) is the largest type of black hole, on the order of hundreds of thousands to billions of solar masses. Most—and possibly all—galaxies are inferred to contain a supermassive black hole at their centers.In the case of the Milky Way, the SMBH is believed to correspond with the location of Sagittarius A*.

For years, astronomers have been puzzled by a bizarre object in the center of the Milky Way that was believed to be a hydrogen gas cloud headed toward our galaxy's enormous black hole. Having studied it during its closest approach to the black hole this summer, UCLA astronomers believe that they have solved the riddle of the object widely known as G2.

A team led by Andrea Ghez, professor of physics and astronomy in the UCLA College, determined that G2 is most likely a pair of binary stars that had been orbiting the black hole in tandem and merged together into an extremely large star, cloaked in gas and dust — its movements choreographed by the black hole's powerful gravitational field. The research is published today in the journal Astrophysical Journal Letters.
"We are seeing phenomena about black holes that you can't watch anywhere else in the universe," Ghez added. "We are starting to understand the physics of black holes in a way that has never been possible before."

Ghez, who studies thousands of stars in the neighborhood of the supermassive black hole, said G2 appears to be just one of an emerging class of stars near the black hole that are created because the black hole's powerful gravity drives binary stars to merge into one. She also noted that, in our galaxy, massive stars primarily come in pairs. She says the star suffered an abrasion to its outer layer but otherwise will be fine.

Astronomers had figured that if G2 had been a hydrogen cloud, it could have been torn apart by the black hole, and that the resulting celestial fireworks would have dramatically changed the state of the black hole. "G2 survived and continued happily on its orbit; a simple gas cloud would not have done that," said Ghez, who holds the Lauren B. Leichtman and Arthur E. Levine Chair in Astrophysics. "G2 was basically unaffected by the black hole. There were no fireworks."

Black holes, which form out of the collapse of matter, have such high density that nothing can escape their gravitational pull — not even light. They cannot be seen directly, but their influence on nearby stars is visible and provides a signature, said Ghez, a 2008 MacArthur Fellow.

The image below shows Sagittarius A* — the giant black hole at the center of our galaxy — appears dim in this composite image because very little material is falling into it.

Ghez and her colleagues — who include lead author Gunther Witzel, a UCLA postdoctoral scholar, and Mark Morris and Eric Becklin, both UCLA professors of physics and astronomy — conducted the research at Hawaii's W.M. Keck Observatory, which houses the world's two largest optical and infrared telescopes.

When two stars near the black hole merge into one, the star expands for more than 1 million years before it settles back down, said Ghez, who directs the UCLA Galactic Center Group. "This may be happening more than we thought. The stars at the center of the galaxy are massive and mostly binaries. It's possible that many of the stars we've been watching and not understanding may be the end product of mergers that are calm now."

Ghez and her colleagues also determined that G2 appears to be in that inflated stage now. The body has fascinated many astronomers in recent years, particularly during the year leading up to its approach to the black hole. "It was one of the most watched events in astronomy in my career," Ghez said.

Ghez said G2 now is undergoing what she calls a "spaghetti-fication" — a common phenomenon near black holes in which large objects become elongated. At the same time, the gas at G2's surface is being heated by stars around it, creating an enormous cloud of gas and dust that has shrouded most of the massive star.

Witzel said the researchers wouldn't have been able to arrive at their conclusions without the Keck's advanced technology. "It is a result that in its precision was possible only with these incredible tools, the Keck Observatory's 10-meter telescopes," Witzel said.

The telescopes use adaptive optics, a powerful technology pioneered in part by Ghez that corrects the distorting effects of the Earth's atmosphere in real time to more clearly reveal the space around the supermassive black hole. The technique has helped Ghez and her colleagues elucidate many previously unexplained facets of the environments surrounding supermassive black holes.

The image at the top of the page is a simulation showing the possible behavior of a gas cloud that has been observed approaching the black hole at the center of the Milky Way.

Source :  daily galaxy

Success in the search for quiet, distant quasars

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If quasars weren’t so luminous, we couldn’t see them so far away in space and time. But how about modest quasars, also far away? Astronomers say they’ve found some.

Astronomers at the Institute of Astrophysics of Andalusia (IAA-CSIC) in Spain say they have at last discovered a population of quiet, distant quasars. Nearly all the quasars we see at great distances are ultraluminous, and no wonder. They must be extremely luminous in order for us to glimpse them over the vastness of space. And yet astronomers have thought there must be, at those same vast distances, some quasars that were relatively quiet. Now, they say, they’ve found some and have been able to compare them both with the ultraluminous quasars in the early universe and also with closer quasars of moderate luminosity.

The farther away we look in space, the deeper we are looking into the past. Thus the ultraluminous quasars at great distances are showing us events taking place in the early universe: mergers of great galaxies containing gigantic black holes, with masses equivalent to billions of our suns, at their cores. These objects and events in the young universe are what we see as the distant quasars. The question has been, do the distant, tremendously high energy quasars have local relatives, in their same region of space and time, with much lower energy? And are those quiet quasars at great distances the dying versions of formerly ultraluminous quasars? Or are they something else entirely?

Jack W. Sulentic, astronomer at the Institute of Astrophysics of Andalusia (IAA-CSIC), who is leading the research, said:

Astronomers have always wanted to compare past and present, but it has been almost impossible because at great distances we can only see the brightest objects and nearby such objects no longer exist.

Until now we have compared very luminous distant quasars with weaker ones close by, which is tantamount to comparing household light bulbs with the lights in a football stadium.

Now, these astronomers say, they have detected the first distant, quiet quasars.

They say they employed the light-gathering power of the Gran Telescopio Canarias – known as GranTeCan or GTC telescope – located on the island of La Palma, in the Canary Islands in Spain. This telescope let Sulentic and his team obtain the first spectroscopic data from distant, low luminosity quasars similar to typical nearby ones.

They say their data are reliable enough to let them establish essential parameters of the quiet, distance quasars such as their chemical composition, and the mass of the central black hole or rate at which it absorbs surrounding gas and dust.

Quasars appear to evolve with distance. That is, the farther away they are in space, the brighter they are. This could indicate that quasars extinguish over time. Or it could be the result of anobservational bias masking a different reality: that gigantic quasars evolving very quickly, most of them already extinct, coexist with a quiet population that evolves more slowly, but which our technological limitations have not allowed astronomers to study. Ascensión del Olmo, another IAA-CSIC researcher who took part in this study, said:

We have been able to confirm that, indeed, apart from the highly energetic and rapidly evolving quasars, there is another population that evolves slowly. This population of quasars appears to follow the quasar main sequence … There does not even seem to be a strong relation between this type of quasars, which we see in our environment and those ‘monsters’ that started to glow more than 10 billion years ago.

Are there also differences between distant, quiet quasars and the moderate quasars closer to us in space? These astronomers say there are, and these differences are not surprising. Jack W. Sulentic said:

The local quasars present a higher proportion of heavy elements such as aluminum, iron or magnesium, than the distant relatives, which most likely reflects enrichment by the birth and death of successive generations of stars.

Bottom line: Astronomers in Spain have been able to identify a population of quiet quasars located in the distant universe, that is, in the early universe. They have compared them both to ultraluminous quasars in the early universe and also to quasars closer to us in space and time … and found differences in both cases.

Source : earth sky