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Post by nyx on Apr 21, 2018 15:44:31 GMT
A long study by the Murchison Widefield Array in Western Australia claims there is nothing special about Oumuamua.
Even though it might have come from another star system, and it is a very long cigar shape, has the color of red, it is not a space ship.
Murchison found no signals coming from Oumuamua.
BUT, the mystery is that scientists claim Oumuamua should have never left its parent solar system.
This object should have never been ejected out into deep space.
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Post by Deleted on Jun 27, 2018 18:55:39 GMT
June 27, 2018 RELEASE 18-056 Our Solar System’s First Known Interstellar Object Gets Unexpected Speed Boost
Using observations from NASA’s Hubble Space Telescope and ground-based observatories, an international team of scientists have confirmed ′Oumuamua (oh-MOO-ah-MOO-ah), the first known interstellar object to travel through our solar system, got an unexpected boost in speed and shift in trajectory as it passed through the inner solar system last year. “Our high-precision measurements of ′Oumuamua’s position revealed that there was something affecting its motion other than the gravitational forces of the Sun and planets," said Marco Micheli of ESA’s (European Space Agency) Space Situational Awareness Near-Earth Object Coordination Centre in Frascati, Italy, and lead author of a paper describing the team's findings. Analyzing the trajectory of the interstellar visitor, co-author Davide Farnocchia of the Center for Near Earth Object Studies (CNEOS) at NASA’s Jet Propulsion Laboratory (JPL) found that the speed boost was consistent with the behavior of a comet. “This additional subtle force on ′Oumuamua likely is caused by jets of gaseous material expelled from its surface,” said Farnocchia. “This same kind of outgassing affects the motion of many comets in our solar system.” Comets normally eject large amounts of dust and gas when warmed by the Sun. But according to team scientist Olivier Hainaut of the European Southern Observatory, “there were no visible signs of outgassing from ′Oumuamua, so these forces were not expected.” The team estimates that ′Oumuamua’s outgassing may have produced a very small amount of dust particles – enough to give the object a little kick in speed, but not enough to be detected. Karen Meech, an astronomer at the University of Hawaii’s Institute of Astronomy and co-author of the study, speculated that small dust grains, present on the surface of most comets, eroded away during ′Oumuamua's long journey through interstellar space. "The more we study ′Oumuamua, the more exciting it gets," Meech said. "I'm amazed at how much we have learned from a short, intense observing campaign. I can hardly wait for the next interstellar object!" ′Oumuamua, less than half a mile in length, now is farther away from our Sun than Jupiter and traveling away from the Sun at about 70,000 mph as it heads toward the outskirts of the solar system. In only another four years, it will pass Neptune’s orbit on its way back into interstellar space. Because ′Oumuamua is the first interstellar object ever observed in our solar system, researchers caution that it’s difficult to draw general conclusions about this newly-discovered class of celestial bodies. However, observations point to the possibility that other star systems regularly eject small comet-like objects and there should be more of them drifting among the stars. Future ground- and space-based surveys could detect more of these interstellar vagabonds, providing a larger sample for scientists to analyze. NASA will host a Reddit Ask Me Anything (AMA) about the ′Oumuamua observations from 4 to 6 p.m. EDT Thursday, June 28. To participate, go to: reddit.com/r/IAMA The international team of astronomers used observations from Hubble, the Canada-France-Hawaii Telescope in Hawaii, and the Gemini South Telescope and European Southern Observatory's Very Large Telescope in Chile. The paper with the team’s findings will appear in the June 27 issue of the journal Nature. JPL hosts CNEOS for the agency’s Near-Earth Object Observations Program, an element of the Planetary Defense Coordination Office within the agency's Science Mission Directorate. Hubble is a project of international cooperation between NASA and ESA. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages Hubble. The Space Telescope Science Institute (STScI) in Baltimore conducts Hubble science operations. www.nasa.gov/press-release/our-solar-system-s-first-known-interstellar-object-gets-unexpected-speed-boost |
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Post by Deleted on Jun 28, 2018 16:25:40 GMT
Quote "Notes [1]`Oumuamua, pronounced “oh-MOO-ah-MOO-ah”, was first discovered using the Pan-STARRS telescope at the Haleakala Observatory, Hawaii. Its name means “scout” in Hawaiian, and reflects its nature as the first known object of interstellar origin to have entered the Solar System. The original observations indicated it was an elongated, tiny object whose colour were similar to that of a comet. [2] The team tested several hypothesis to explain the unexpected change in speed. They analysed if solar radiation pressure, the Yarkovsky effect, or friction-like effects could explain the observations. It was also checked if the gain in speed could have been caused by an impulse event (such as a collision), by `Oumuamua being a binary object or by `Oumuamua being a magnetised object. The unlikely theory that `Oumuamua is an interstellar spaceship was also rejected: the facts that the smooth and continuous change in speed is not typical for thrusters and that the object is tumbling on all three axis speak against it being an artificial object." www.eso.org/public/news/eso1820/ |
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Post by swamprat on Dec 26, 2018 0:04:42 GMT
How the Oumuamua mystery shook up the search for space aliens
The interstellar visitor made it respectable to talk about alien spaceships.
By Corey S. Powell
Dec. 25, 2018 / 6:00 AM EST
Last year, an enigmatic object named Oumuamua startled astronomers when it came streaking past the sun, giving humanity its first close-up look at an object from beyond our solar system. This year, the interstellar visitor did something even more remarkable: It made it respectable to talk about alien spaceships.
The turning point came in November, when Avi Loeb, the head of the astronomy department at Harvard University, co-wrote a paper saying that Oumuamua is so unusual that scientists should consider the possibility that it’s not a far-out comet or asteroid, as his colleagues assumed, but rather an artificial structure.
In other words, maybe it’s an interstellar craft built by extraterrestrials.
Some of Loeb’s colleagues were intrigued. Others were disconcerted. But suddenly mainstream scientists were talking about how to tell if Oumuamua is a natural object or — as Loeb raised as a possibility in his paper — an alien spacecraft designed to capture the force of sunlight (a so-called lightsail).
Loeb is well aware that most scientists recoil from anything that sounds like UFO craziness, but he believes an overabundance of skepticism has cut them off from out-of-the box ideas. “The point of doing science is not to have a prejudice,” he says. “A prejudice is based on the experience of the past, but if you want to allow yourself to make discoveries, then the future will not be the same as the past.”
Jason Wright, a Penn State astronomer who recently launched a graduate program in SETI (the search for extraterrestrial intelligence), shares Loeb’s desire for open discussion — and offers an upbeat assessment of the field’s growing respectability. “There’s a real culture change. SETI is becoming a serious scientific discipline,” he says.
Strange Visitor From the Stars
It was clear from the start that Oumuamua (pronounced oh-MOO-uh-MOO-uh) would shake up astronomy’s status quo. Shortly after its discovery, scientists realized that the object’s unusual trajectory meant it had to have come from outside the solar system — and that it could have been traveling for millions of years. They quickly dubbed the mysterious object Oumuamua, a Hawaiian word meaning “messenger from the past.”
There were more surprises. Oumuamua was too far away for astronomers to observe its shape directly, but they could tell by the extreme way its brightness shifted as it tumbled through space that it wasn’t like any space rock they had ever seen.
“It’s very elongated, with an axis ratio of at least 7 to 1,” astronomer Karen Meech of the University of Hawaii said in an email. In other words, it’s at least seven times as long as it is wide — shaped like a cigar, perhaps. Or, as Loeb proposes in his paper, maybe a flattened disk.
Source: Patrick Treuthardt, Ph.D. The relative size of 'Oumuamua, the first extra-solar asteroid discovered. Original images: M. Kornmesser/ESO, Daniel Schwen
Astronomers’ models predict that most of the small bodies wandering in interstellar space are comets. But when Meech and others examined it, Oumuamua showed no sign of the expected comet-like tail. It’s also quite small, on the order of 1,000 feet long, and it seems to be much more reflective than the comets we know.
Intrigued by its oddities, several groups of SETI researchers listened for possible radio transmissions from Oumuamua — and heard nothing.
An Invisible Push
The biggest puzzle about Oumuamua was the way it moved. As it zoomed away from the sun, it sped up slightly, as if given an invisible push. “It doesn’t take much to provide the little acceleration we see,” says Michele Bannister, a comet expert at Queens University Belfast, “but the effect is definitely there.”
Comets often accelerate that way when gases boil off their surface under heat from the sun. But observations by the Spitzer Space Telescope showed no such material coming off of Oumuamua.
At this point, Loeb thought it was time to consider a more radical interpretation and, with a post-doctoral student, Shmuel Bialy, wrote the provocative paper. In it, the scientists consider the possibility that Oumuamua lacks a tail because it isn’t a comet at all, and that the acceleration was caused not by boiling gases but by the pressure of sunlight against a very wide, thin lightweight structure.
“The Spitzer data are consistent with a sail about 20 meters [60 feet] across,” Loeb says. He and Bialy suggest that such an object could be technological debris or even “a fully operational probe.”
Stirring the SETI Pot
Loeb anticipated a harsh reaction to his paper, and his expectation was soon fulfilled. Twitter buzzed with snide comments. “A new paper, which claims Oumuamua is an alien probe, is full of poop,” one skeptic tweeted. “The Loeb paper says WHAT IF ALIEN LIGHT SAILS? Occam says no,” tweeted another in a reference to Occam’s Razor (a philosophical principle that when there are two competing explanations for an occurrence, the simpler one is usually better).
One researcher, who asked to remain anonymous, disparaged the Bialy and Loeb paper as “irresponsible,” and said it was “just out to grab attention.”
Loeb shrugs off the reflexive dismissals, but partly embraces that last critique, saying his lofty academic position actually obligates him to be a pot-stirrer: “I can say these things other people can’t because I have tenure at Harvard. The whole idea of getting tenure is to allow you to be free in your mind. I used the opportunity of Oumuamua to make a statement.”
In his view, searching for evidence of alien artifacts is no more outrageous than physicists exploring higher dimensions or astronomers invoking dark matter to explain the motions of galaxies. Or, more to the point, no more outrageous than searching for microbes on Mars.
“All I’m doing is following the standard scientific process, looking for explanations,” Loeb says.
What’s different is that the stakes are so high. Finding evidence of an extraterrestrial civilization would be far more profound than finding extraterrestrial microbes. It would tell us that humans aren’t the only intelligent species around.
A Universe of Questions
Wright believes the excitement over Oumuamua, combined with the other recent developments in the field, is breathing new life into SETI research.
“There’s a popular misperception that it’s just people listening for radio signals and coming up with one null result after another,” he says of SETI. He counters that there are actually a tremendous number of ways to search for alien life once scientists broaden their horizons.
Wright raises the possibility that a now-defunct alien civilization left behind artifacts on the moon, where they could have survived even if deposited there billions of years ago. His colleague Paul Davies at Arizona State University has enlisted students to comb through archival images of the lunar surface to see if they can find evidence of any alien “technosignatures.”
Wright has participated in studies of Tabby’s Star, whose intermittent dimming had some scientists wondering if it was encased within a vast artificial structure built by aliens. While the latest results show that’s not the case, Wright is undeterred. Almost all such searches are destined for failure, he says, and all it takes is one success to change the world.
With that in mind, he advocates digging through existing astronomical data to look for other stars whose peculiar behavior could indicate the presence of alien construction projects. “There are many rich datasets sitting out there to look through,” he says.
This is exactly the sort of unfettered curiosity that Loeb says he wanted to spark with his Oumuamua hypothesis. “Why have a prejudice? Why argue that it must be natural? What do we gain, other than putting blinders on our eyes?” he asks. “We should examine each and every interstellar object entering the solar system to check if it’s natural or not. Even if most of the time it’s natural, every now and then we might be surprised.”
And what a surprise that would be.
www.nbcnews.com/mach/science/how-oumuamua-mystery-shook-search-space-aliens-ncna950991
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