Category: Astronomy and Space
Astronomers have found evidence of hidden supermassive black holes in the universe.
Using NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) satellite observatory, the team detected the high-energy x-rays from five supermassive black holes previously clouded from direct view by dust and gas.
The research, led by astronomers at Durham University in Britain, supports that potentially millions more supermassive black holes exist in the Universe, but are hidden from view.
“We have been able to clearly see these hidden monsters that were predicted to be there but had been elusive because of their ‘buried’ state,” said lead author George Lansbury, post-graduate student in the centre for extragalactic astronomy.
Although only five of these hidden supermassive black holes have been detected, “when we extrapolate our results across the whole universe, then the predicted numbers are huge and in agreement with what we would expect to see”, Lansbury said.
The scientists pointed NuSTAR at nine candidate hidden supermassive black holes that were thought to be extremely active at the centre of the galaxies.
High-energy x-rays found five of the black holes, and confirmed that they had been hidden by dust and gas.
The five were much brighter and more active than previously thought as they rapidly feasted on surrounding material and emitted large amounts of radiation.
The results were presented at the Royal Astronomical Society’s national astronomy meeting in Llandudno, Wales on July 6.
In the year 1851 cultivated persons in cities throughout Europe went to the largest cathedrals to attend an unusual sort of worship. They were coming to witness Jean Foucault’s pendulum experiment, which he had first performed for the public in that year under the dome of the Pantheon in Paris.
From the highest point in the cathedral a heavy weight hung suspended on a thin rope, so that it was free to swing in all directions. it was given a push in a northerly direction, and began to swing in a north-south line. It continued to swing for days, but ever so slowly the direction of its swing shifted. And it continued to do so visibly. Those who waited long enough were able to see the plane of the pendulum’s swing turn in a full circle in the course of a day.
Actually, however, the plane of oscillation had not change d at all. A pendulum retains the direction of its original motion, as stated by Galileo’s law of inertia. Thus the pendulum provided visible proof of Copernicus’ doctrine: the Earth was turning underneath the swinging pendulum.
How unfortunate it was that Galileo did not notice this when he observed the chandelier swinging in the Duomo at Pisa. He would have been spared his troubles with the Inquisition; such tangible proof of the Earth’s rotation would have silenced all doubts.
Nevertheless, the Frenchman’s ingenious experiment stimulated other ideas, for which the times and the place were ready: ideas on one of the fundamental problems of both philosophy and religion.
Originally Newton had asked himself whether absolute movement existed in the universe, that is to say, movement in itself which we could determine without reference to other movements. His answer was that there was only one such motion: the rotation of the Earth. Ultimately, he maintained, we would have discovered this motion even if there had not been a sky full of stars circling about the polestar above our heads. Even without the polestar we would have found the flattened poles of our globe; we would have understood that they had been caused by the distorting effect of centrifugal force.
From this reasoning Newton drew a profound conclusion. If we imagine our universe with no other bodies beside the Earth, there must still be something to which we can refer the motion of the Earth, something that is at rest in relation to the Earth. Absolute motion presupposes something absolutely at rest. Only space can be this something. Hence, space ceases to be solely a philosophical concept, a mere word; it must have physical existence, for all that its only characteristic is being at rest. This idea of something at rest, ubiquitous, absolutely fixed, suggested the attributes of the Supreme Being; physical space of its own accord intruded itself into the sphere of religion.
Assuming the standard model is true, our universe’s end will likely all come down to one of three theories, each of which depends upon three things: the shape of the universe, how much dark energy is contained within it, and how the densities of dark energy will respond to the expansion of the universe.
There are believed to be three possible shapes of the universe: an open universe, a flat universe, and a closed plane of space-time.
In an open universe (think of a gigantic, saddle-shaped object), the universe is likely to experience the Big Freeze. In this scenario, the universe will continue to expand until matter has stretched incredibly thin, the stars have all burnt out, galaxies have ceased creating new stars to replace them, and all mass as we know it has ceased to exist. Everything will become dark and cold. The universe won’t so much as end as it will simply fizzle out, settling into a silent and lonely slumber at absolute zero.
Another possibility for universal armageddon is the Big Rip. Not as dependent on the shape of the universe as much as the amount of dark energy contained within it, this model implies that the acceleration of the universe will continue to increase without slowing, and the dark energy will become so strong that it will overwhelm the other elemental forces. Galaxies, suns, and planets alike will begin tearing themselves apart, all ending in a gravitational singularity — a place in which the standard rules of physics and relativity no longer apply.
Somewhat less unsettling is the theory of the Big Crunch, in which the universe will continue to expand until matter begins to slow the rate of expansion. Once slowed enough, the expansion will eventually come to a halt and begin to retract. Everything — planets, suns, galaxies, black holes, even the indestructible iPad 7000 — will all come crashing back together, culminating in a Big Crunch: essentially the opposite of the Big Bang that kicked our universe off in the first place. The bright side here is that the crunch is thought to be succeeded by yet another Big Bang and the creation of a whole new universe. Unfortunately, of the three, the Big Crunch is currently the least favored hypothesis within the physics community — meaning our dreams of an endlessly cycling universe of birth, destruction, and rebirth may end up being relegated to the realm of science fiction.
Dark matter continues to confound astronomers, as NASA’s Chandra X-ray Observatory demonstrated with the detection of an extensive envelope of dark matter around an isolated elliptical galaxy. This discovery conflicts with optical data that suggest a dearth of dark matter around similar galaxies, and raises questions about how galaxies acquire and keep such dark matter halos.
Dark matter is a mysterious kind of glue that holds not only the mysterious together, but is theoretically responsible for their creation. It was originally suggested in 1933 to explain discrepancies math by calculating the mass of galaxies, essentially, more material is needed to keep the galaxies together, we can see. Since then, we have not learned a whole hell of a lot more about dark matter.
In fact, we seem to know more about this itisn’t than it is. We know there is no antimatter. We also know that there is no dark clouds of normal matter. Many physicists believe that it represents about 83% of matter in the universe – even if we still have to prove that it exists!
The tricky thing with the dark matter is that we can not be detected directly, it is invisible. Dark matter is revealed by its severity, so we have, instead of measuring it through its interaction with normal matter. Currently, there are two contradictory experiments conducted in an attempt to confirm the existence of dark matter.
The Cryogenic Dark Matter Search (CDMS) detector Sudan mine in Minnesota is the search for weakly interacting massive particles, or WIMPs, whose discovery could resolve the problem of dark matter. Although the dark matter should be everywhere, it is estimated that some WIMPs can pass through the galaxy without interacting with normal matter, making it very difficult to discover. Although scientists have not yet detected WIMPs directly, they found significant evidence that they exist.
In direct conflict with these results, the XENON100 experience in Gran Sasso Laboratory in Italy has so far yielded negative results with respect to the WIMP. This does not mean that WIMPs exist, but simply that they are harder to detect than scientists had previously assumed.
For 50 years now humans have been scanning the skies in hopes of answering the question: Are we alone in the universe?
That mystery will be the topic of discussion during this weekend’s SETIcon, a convention for scientists, sci-fi writers, celebrities and fans to discuss every aspect of the Search for Extraterrestrial Intelligence (SETI).
SPACE.com caught up with Jill Tarter, director of the Center for SETI Research (and the basis for the main character Ellie Arroway portrayed by Jodie Foster in the film “Contact” based on the book by astronomer-author Carl Sagan), to discuss the last 50 years since the first effort to listen for extraterrestrial intelligence in the universe, and the outlook for the future:
After 50 years, what’s the status of the search for extraterrestrial intelligence?
It is interesting that at age 50, what we’re doing is reinventing ourselves. I think that’s a good sign. We’re not going to stop doing what we’ve done — radio searching still makes a lot of sense. But optical searching also makes a lot of sense.
We’re going to try to get away from doing it all ourselves, and ask the world to join in. The world has shown an interest over the past decade in participating.
We haven’t really succeeded in getting people involved internationally. You’re skimming only the technological top of the global population. I’m actually hoping that the enormous prevalence of cell phones and social networking will finally allow us to.
Has the journey of SETI over the last 50 years played out like you thought it would?
I don’t think any of us were smart enough 50 years ago to anticipate how rapidly the capability of our searches was going to improve. Fifty years ago was pretty much pre-digital revolution. I can count almost 15 orders of magnitude improvement in the tools of radio observing.
Fifty years ago optical search was out of the question. We couldn’t count photons fast enough. When that technology got there, wow, we just jumped on it.
Fifty years ago nobody thought you could or should build an array of 50 small telescopes. Now the right thing to do is use inexpensive antennas and inexpensive electronics and combine them together. You get your value that way.
Back then, what got you interested in looking for life out there in the universe?
The thing that got me hooked on SETI about 40 years ago was the fact that we suddenly had some tools. These tools called radio telescopes could allow us to do an experiment to explore, rather than ask philosophers what we should believe. It’s all about replacing the [idea] of what should we believe, with ‘let’s explore.’
What do you say to people who think there’s no hope of finding extraterrestrials and that searching is a waste?
We appear to be the results of the laws of physics and chemistry. It’s not unreasonable to wonder whether elsewhere, the same sorts of processes led to other intelligence and technologies.
Fifty years is a very small time in the lifetime of a galaxy which is 12 billion years old. We’re a very young technology in a very old galaxy. We kind of shouldn’t be surprised we haven’t found them yet. It’s a big search. We don’t go to bed disappointed, we wake up in the morning excited.
How do you think you’d feel if we did discover evidence of alien life?
The feeling would be phenomenal. To have posed a question and gotten an answer that no one else has been able to come up with. That would tell us something about the universe that we didn’t already know. Just a proof of existence; that would be amazing for me.
If extraterrestrials do exist, what do you imagine they might be like?
Who knows? Extraterrestrial psychology is one notch above where I’m prepared to go. I will say it’s statistically overwhelmingly likely that they are much older than we are. If they were younger than we are, then there isn’t any technology of theirs we could detect.
If we detect a signal we’ll know it’s possible for us to have a long future.
What do you predict the next 50 years might hold for SETI?
I’m pretty darn sure that long before 50 years from now Kepler or some other mission will have detected earth-size planets in the habitable zones of their stars and we will have been able to look remotely for biosignatures.
We may have understood whether or not there’s some sort of life on the planet. We may not be able to tell the difference between microbes and mathematicians, but at least we’ll have places to study from afar.
A mysterious light forces an airport closure and is photographed by many residents.
On July 7, something unusual happened near the Xiaoshan Airport in Hangzhou, China. An oddly shaped bright light appeared, forcing the airport to close down and delay 18 flights. Things are now back to normal, but people are wondering, what was that “thing”?
An ABC News article on the mysterious sighting explains that some who witnessed the light are calling it a UFO. But, keep in mind, a UFO doesn’t necessarily mean little, green men.
There is plenty of speculation on whether or not the object was some sort of military aircraft or missile. The ABC article explains that a day following the sighting, “an anonymous source told China Daily that authorities already discovered the identity of the UFO after an investigation but could not publically disclose the information because ‘there was a military connection.’”
Authorities are continuing to look into the incident, but no public conclusions have yet been made. Despite, or perhaps because of the mystery, Web searches on “china ufo” quickly soared 576%. Related queries on “china ufo video 2010,” “china ufo sightings,” and “hangzou china ufo” also posted triple digit gains. Even now, a week after the sighting, online lookups remain high.
Truth be told, there’s not much left to be said. Something weird happened. Nobody knows what it was. And if they do, they aren’t saying.
A Moon landing is the arrival of a spacecraft on the surface of the Moon. This includes both manned and unmanned (robotic) missions. The first human-made object to reach the surface of the Moon was the Soviet Union’s Luna 2 mission, on 13 September 1959.
The United States’ Apollo 11 was the first manned mission to land on the Moon, on 20 July 1969. There have been six manned U.S. landings (between 1969 and 1972) and numerous unmanned landings, with no soft landings happening from 22 August 1976 until 14 December 2013.
To date, the United States is the only country to have successfully conducted manned missions to the Moon, with the last departing the lunar surface in December, 1972.
“A lot of people couldn’t figure out Armstrong.”
With those words Tom Wolfe introduced Neil Armstrong, the astronaut hero of his nonfiction masterpiece, “The Right Stuff.” Armstrong, of course, was a masterpiece himself: the commander of the 1969 Apollo 11 mission and the first man ever to walk on the moon. Armstrong died Saturday from complications relating to heart surgery. He was 82.
All these decades, Armstrong, the lunar Adam, has represented a code his admirers knew better than to try to crack. Not that, early on, great literary minds—besotted by the baby-faced genius—didn’t try.
Wolfe continued: “You’d ask him a question, and he would just stare at you with those pale-blue eyes of his, and you’d start to ask the question again, figuring he hadn’t understood, and— click —out of his mouth would come forth a sequence of long, quiet, perfectly formed, precisely thought-out sentences.”
So Wolfe warned against understanding Armstrong in “The Right Stuff.” And that warning was more or less heeded, somewhat miraculously, until Armstrong’s dying day. Profilers kept their mitts off him. Hollywood starlets didn’t swoop in to wreck his family. And, most mercifully of all, Carson and Merv Griffin and Dinah Shore and Ali G and Oprah didn’t demand that he couch-surf with them.
This is astounding. In the 1960s and ’70s , the national pastime was psychologizing postwar celebrities—John F. Kennedy, Marilyn Monroe, Muhammad Ali. And once a hero is cracked open by one Vanity Fair profile, the pile-on never ends. This one had a sex addiction; this one had a chip on her shoulder; this one could never live up to his big brother.
Let’s not do that to Armstrong, Wolfe pleaded. In any case, the great man simply would not succumb. Armstrong was simply, at heart, not homo psychologico. He was homo machinator, homo ingeniator. The engineering man.
In an era when everyone was expected to evince the adolescent emotionality of Marlon Brando or Allen Ginsberg, Armstrong was resolutely adult and elegantly square. He was a Navy pilot from a small town who married a home-ec major at Purdue whom he had no recollection of courting or even proposing to. (Janet Armstrong, with whom he had three children, evidently didn’t remember any courtship either.)
Though astronauts in the time were represented as hard-partying matinee idols, Armstrong always described himself as a “white-socks, pocket-protector, nerdy engineer.” He wasn’t boasting, though engineers are, of course, the hotshots of today: the hackers and technologists who keep pushing into the new breach—the postfinal frontiers of cyberspace.
Once in 1969, Norman Mailer bullied Armstrong into saying something—anything—romantic about going to the moon. (Armstrong would have to cough up the romance, Mailer wrote, or be considered “a spiritual neuter.”) Armstrong stood his ground like a Buddha. “I think we’re going to the moon because it’s in the nature of the human being to face challenges,” he said, defying Mailer. “It’s by the nature of his deep inner soul… We’re required to do these things just as salmon swim upstream.”
Those words are perhaps the most gorgeous words the press-shy astronaut ever said, including his famous scripted line about the giant leap.
Michael Collins, an Apollo 11 crewmate, wrote that Armstrong “never transmits anything but the surface layer, and that only sparingly… I like him, but I don’t know what to make of him, or how to get to know him better.”
Maybe we weren’t meant to fully understand Armstrong. Only to hold him in awe. Like the moon itself.
Each of the two gargantuan objects is 10 billion times the size of our sun.
Scientists have found the biggest black holes known to exist — each one 10 billion times the mass of our sun. A team led by astronomers at the University of California, Berkeley, discovered the two gigantic black holes in clusters of elliptical galaxies more than 300 million light years away. That’s relatively close on the galactic scale.
“They are monstrous,” Berkeley astrophysicist Chung-Pei Ma told reporters. “We did not expect to find such massive black holes because they are more massive than indicated by their galaxy properties. They’re kind of extraordinary.”
The previous black hole record-holder is as large as 6 billion suns. In research released Monday by the journal Nature, the scientists suggest these black holes may be the leftovers of quasars that crammed the early universe. They are similar in mass to young quasars, they said, and have been well hidden until now.
The scientists used ground-based telescopes as well as the Hubble Space Telescope and Texas supercomputers, observing stars near the black holes and measuring the stellar velocities to uncover these vast, invisible regions.
Black holes are objects so dense that nothing, not even light, can escape. Some are formed by the collapse of a super-size star. It’s uncertain how these two newly discovered whoppers originated, said Nicholas McConnell, a Berkeley graduate student who is the study’s lead author. To be so massive now means they must have grown considerably since their formation, he said.
Most if not all galaxies are believed to have black holes at their center. The bigger the galaxy, it seems, the bigger the black hole. Quasars are some of the most energized and distant of galactic centers.
The researchers said their findings suggest differences in the way black holes grow, depending on the size of the galaxy. Ma speculates these two black holes remained hidden for so long because they are living in quiet retirement — much quieter and more boring than their boisterous youth powering quasars billions of years ago.
“For an astronomer, finding these insatiable black holes is like finally encountering people nine feet tall whose great height had only been inferred from fossilized bones. How did they grow so large?” Ma said in a news release. “This rare find will help us understand whether these black holes had very tall parents or ate a lot of spinach.”
Oxford University astrophysicist Michele Cappellari, who wrote an accompanying commentary in the journal, agreed that the two newly discovered black holes “probably represent the missing dormant relics of the giant black holes that powered the brightest quasars in the early universe.”
One of the newly detected black holes weighs 9.7 billion times the mass of the sun. The second, slightly farther from Earth, is as big or even bigger. Even larger black holes may be lurking out there. Ma said that’s the million-dollar question: How big can a black hole grow?
The researchers already are peering into the biggest galaxies for answers. “If there is any bigger black hole,” Ma said, “we should be able to find them in the next year or two. Personally, I think we are probably reaching the high end now. Maybe another factor of two to go at best.”
The world’s biggest astronomy project provides a view of space unmatched by other observatories.
A powerful telescope affording a view of the universe unmatched by most ground-based observatories gazed onto distant galaxies for the first time Monday from deep in Chile’s Atacama desert.
The Atacama Large Millimeter/submillimeter Array, a joint project between Canada, Chile, the European Union, Japan, Taiwan and the United States, officially opened for astronomers after a decade of planning and construction.
The world’s biggest astronomy project, ALMA is described as the most powerful millimeter/submillimeter-wavelength telescope ever and the most complex ground-based observatory.
The first images arrived at the mega-site in northern Chile from 12 of the 66 radio telescopes.
“Today marks the recognition of the successful coalition of thousands of people from all over the world all working with the same goal: to build the world’s most advanced radio telescope to see into the universe’s coldest, darkest places, where galaxies and stars and perhaps the building blocks of life are created,” said ALMA director Thijs de Graauw.
ALMA differs from visible-light and infrared telescopes by using an array of linked antennas acting as a single giant telescope, and detects much longer wavelengths than those of visible light, rendering images unlike most others of the cosmos.