SpaceJibe

January 21, 2016

There’s a ninth planet out there – now we just need to find it

Filed under: Exoplanets, Kuiper Belt, Outer Solar System — bferrari @ 6:31 pm

Mathematics suggests hidden gas giant in solar system

The truth is out there; way, way out there (source: CalTech/R.Hurt)

The truth is out there; way, way out there (source: CalTech/R.Hurt)

Pic Scientists at CalTech claim to have found proof that there is a ninth planet in the solar system, using computer modeling and historical astronomy data.

The new planet has a mass about 10 times that of Earth and has a very eccentric path around our Sun, making one complete orbit every 10,000 or 20,000 years and travelling 200 times further from the Sun than our orbit. The planet hasn’t been seen, but can be determined to exist based on its effect on objects in the Kuiper Belt that encircles our solar system.

“This would be a real ninth planet,” said Mike Brown, the Richard and Barbara Rosenberg Professor of Planetary Astronomy at the California Institute of Technology. “There have only been two true planets discovered since ancient times, and this would be a third. It’s a pretty substantial chunk of our solar system that’s still out there to be found, which is pretty exciting.”

That’s true, thanks to our modern definition of what a planet is. We’ve known about all the planets as far out as Saturn since before telescopes, and the advent of optics led to the discovery of Uranus back in 1781.

The existence of Neptune, like the new ninth planet, was proved mathematically before it was identified in 1846 based on the erratic movement of Uranus. Pluto was also proved mathematically to exist but it was nearly 100 years later before it was confirmed, and then demoted to dwarf planet status in an infamous 2006 astronomers’ vote.

There’s no fear of that in the case of the new ninth planet – it’s massive enough to cause objects in the Kuiper Belt to move in such a predictable fashion that Brown and his associate Konstantin Batygin estimate there’s only a 0.07 per cent possibility that they are mistaken about its existence.

In a paper published in the latest issue of The Astronomical Journal, the duo detail how they came to find the planet when a student of Brown’s noticed that 13 large objects in the Kuiper Belt were behaving oddly, as though they were being influenced by a much larger body.

Brown and Batygin spent the next 18 months building up complex mathematical simulations of what could be causing the movement and running them through a computer model. Brown supplied the astronomical data and Batygin applied physics to see what could be going on.

“I would bring in some of these observational aspects; he would come back with arguments from theory, and we would push each other. I don’t think the discovery would have happened without that back and forth,” said Brown. “It was perhaps the most fun year of working on a problem in the solar system that I’ve ever had.”

At first the two considered that maybe other Kuiper Belt objects were causing the orbital anomalies, but the sums didn’t add up – the Belt would have had to have 100 times the mass we understand it has. So that left the influence of a planet, and one that was orbiting the Sun at right angles to the orbits of other planets.

orbits

“Your natural response is ‘This orbital geometry can’t be right. This can’t be stable over the long term because, after all, this would cause the planet and these objects to meet and eventually collide,'” said Batygin. “Still, I was very skeptical. I had never seen anything like this in celestial mechanics.”

In order for the theory to be accurate, there would have to be other Kuiper Belt objects on a similar 90-degree trajectory. After three years of looking, the two found four largish objects that did just that.

“We plotted up the positions of those objects and their orbits, and they matched the simulations exactly,” says Brown. “When we found that, my jaw sort of hit the floor.”

Planets are supposed to form from the disk of matter that surrounds a young star, but the unusual orbit suggests that while the ninth planet might have started that way, it got knocked out of alignment, possibly by a major object like Jupiter, and sent on a new orbital trajectory.

Despite orbiting so far away from the Sun, planet nine should still be visible using our most powerful telescopes, and may have been picked up on star surveys and not recognized for what it is. The hunt is now on to be the first to get a clear sighting.

“I would love to find it,” says Brown. “But I’d also be perfectly happy if someone else found it. That is why we’re publishing this paper. We hope that other people are going to get inspired and start searching.”

Source

September 20, 2015

Stunning 7-mile scale model of the solar system created in Nevada

Filed under: Cool, Earth, inn, Inner Solar System, Outer Solar System — bferrari @ 9:06 am

A group of friends has created a stunning 7-mile scale model of the solar system on a dry lakebed in Nevada.

“The only way to see a scale model of the solar system was to build one,” explained science film-maker, noting the vast distances between planets. The visually striking project is documented in “To Scale: The Solar System” a 7-minute short film by Overstreet and Alex Gorosh.

Related: NASA releases dramatic new Pluto images

In the scale model Mercury, Venus and Earth are, respectively, 224 feet, 447 feet and 579 feet away from the Sun. Jupiter, Saturn and Uranus are, respectively, 0.57 miles, 1.1 miles and 2.1 miles from the fiery orb with Neptune 3.5 miles away, right on the edge of the solar system.

In reality, Neptune is around 2.8 billion miles from the Sun.

The group used cars to trace the planets’ orbits. Time lapse shots were taken from the top of a nearby mountain, creating a striking representation of the vast solar system.

To Scale: The Solar System from Wylie Overstreet on Vimeo.

January 28, 2015

‘Super Saturn’ with rings 200 times as large

Filed under: Cool, Outer Solar System — bferrari @ 12:49 pm
Illustration by artist Ron Miller of the gigantic ring system around J1407b.

Illustration by artist Ron Miller of the gigantic ring system around J1407b.

In 1610, after he built his telescope, Galileo Galilei first spotted enormous Saturn’s gigantic rings. More than 400 years later, astronomers have in a sense dwarfed that discovery with a similar first.

Using powerful optics, they have found a much larger planet-like body, J1407b, with rings 200 times the size of Saturn’s, U.S. and Dutch astronomers said.

It lies some 400 light-years away from Earth.

For decades, scientists have believed that many moons around large planets formed out of such ring systems. But this is the first one astronomers have observed aside from Saturn’s, they said.

It was discovered in 2012, but a detailed analysis of its data was recently completed and published.

Dominating the sky

How this new Super Saturn would look in our own sky.

How this new Super Saturn would look in our own sky.

If J1407b were in our solar system, it would dominate Earth’s nightly sky.

“If we could replace Saturn’s rings with the rings around J1407b, they would be easily visible at night and be many times larger than the full moon,” said Matthew Kenworthy from the Netherlands’ Leiden Observatory.

Unlike Galileo peering a relatively short distance through his simple telescope, today’s astronomers can’t eyeball the rings hundreds of light-years away.

But using two very powerful optical devices with eight cameras each, they can observe the effect the rings have as they pass across nearby star J1407 — written without a ‘b’ at the end.

It is similar to our sun. The rings of planet J1407b eclipse its light.

56-day eclipse

With the enormous size of the rings, the eclipse the astronomers observed lasted 56 days.

But the star did not go completely dark for nearly two months. Some of J1407b’s 30 rings are denser, blocking more light, and some of them are less dense, letting more light through.

And there are gaps between the rings, leading the scientists to theorize that “exomoons” have formed and cut clean orbits through the debris, like the moons around Saturn.

Our own solar system’s ringed giant has at least 60 moons, according to NASA.

Bigger than a planet

Like its system of rings, planet J1407b is also much larger than Saturn, said astrophysicist Eric Mamajek, whose team at the University of Rochester discovered the object. “You could think of it as kind of a super Saturn.”

It is called a brown dwarf, a size classification somewhere between a planet and a star, according to the California Institute of Technology.

Brown dwarfs are hot but don’t burst into nuclear fusion the way stars do, so they don’t give off light.

The scientists are calling on amateur astronomers to keep an eye on star J1407 in hopes they may observe the rings eclipsing it again and report the results to the American Association of Variable Star Observers, which collects astronomical data on “stars that change in brightness.”

And astronomers will also search for more such ringed systems.

November 12, 2014

TOUCHDOWN ! Rosetta’s Philae Probe Touches Down on a Comet !

Filed under: Comets, Gadgets, Kuiper Belt, Oort Cloud — bferrari @ 2:25 pm
Farewell Philae - narrow-angle view

Farewell Philae – narrow-angle view

ESA’s Rosetta mission has soft-landed its Philae probe on a comet, the first time in history that such an extraordinary feat has been achieved.

After a tense wait during the seven-hour descent to the surface of Comet 67P/Churyumov–Gerasimenko, the signal confirming the successful touchdown arrived on Earth at 16:03 GMT (17:03 CET).

The confirmation was relayed via the Rosetta orbiter to Earth and picked up simultaneously by ESA’s ground station in Malargüe, Argentina and NASA’s station in Madrid, Spain. The signal was immediately confirmed at ESA’s Space Operations Centre, ESOC, in Darmstadt, and DLR’s Lander Control Centre in Cologne, both in Germany.

The first data from the lander’s instruments were transmitted to the Philae Science, Operations and Navigation Centre at France’s CNES space agency in Toulouse.

“Our ambitious Rosetta mission has secured a place in the history books: not only is it the first to rendezvous with and orbit a comet, but it is now also the first to deliver a lander to a comet’s surface,” noted Jean-Jacques Dordain, ESA’s Director General.

“With Rosetta we are opening a door to the origin of planet Earth and fostering a better understanding of our future. ESA and its Rosetta mission partners have achieved something extraordinary today.”

“After more than 10 years travelling through space, we’re now making the best ever scientific analysis of one of the oldest remnants of our Solar System,” said Alvaro Giménez, ESA’s Director of Science and Robotic Exploration.

“Decades of preparation have paved the way for today’s success, ensuring that Rosetta continues to be a game-changer in cometary science and space exploration.”

“We are extremely relieved to be safely on the surface of the comet, especially given the extra challenges that we faced with the health of the lander,” said Stephan Ulamec, Philae Lander Manager at the DLR German Aerospace Center.

“In the next hours we’ll learn exactly where and how we’ve landed, and we’ll start getting as much science as we can from the surface of this fascinating world.”

Rosetta was launched on 2 March 2004 and travelled 6.4 billion kilometres through the Solar System before arriving at the comet on 6 August 2014.

Philae touchdown

Philae touchdown

“Rosetta’s journey has been a continuous operational challenge, requiring an innovative approach, precision and long experience,” said Thomas Reiter, ESA Director of Human Spaceflight and Operations.

“This success is testimony to the outstanding teamwork and the unique know how in operating spacecraft acquired at the European Space Agency over the decades.”

The landing site, named Agilkia and located on the head of the bizarre double-lobed object, was chosen just six weeks after arrival based on images and data collected at distances of 30–100 km from the comet. Those first images soon revealed the comet as a world littered with boulders, towering cliffs and daunting precipices and pits, with jets of gas and dust streaming from the surface.

Following a period spent at 10 km to allow further close-up study of the chosen landing site, Rosetta moved onto a more distant trajectory to prepare for Philae’s deployment.

Five critical go/no-go decisions were made last night and early this morning, confirming different stages of readiness ahead of separation, along with a final preseparation manoeuvre by the orbiter.

Deployment was confirmed at 09:03 GMT (10:03 CET) at a distance of 22.5km from the centre of the comet. During the seven-hour descent, which was made without propulsion or guidance, Philae took images and recorded information about the comet’s environment.

“One of the greatest uncertainties associated with the delivery of the lander was the position of Rosetta at the time of deployment, which was influenced by the activity of the comet at that specific moment, and which in turn could also have affected the lander’s descent trajectory,” said Sylvain Lodiot, ESA Rosetta Spacecraft Operations Manager.

“Furthermore, we’re performing these operations in an environment that we’ve only just started learning about, 510 million kilometres from Earth.”

Touchdown was planned to take place at a speed of around 1 m/s, with the three-legged landing gear absorbing the impact to prevent rebound, and an ice screw in each foot driving into the surface.

But during the final health checks of the lander before separation, a problem was detected with the small thruster on top that was designed to counteract the recoil of the harpoons to push the lander down onto the surface. The conditions of landing – including whether or not the thruster performed – along with the exact location of Philae on the comet are being analysed.

The first images from the surface are being downlinked to Earth and should be available within a few hours of touchdown.

Over the next 2.5 days, the lander will conduct its primary science mission, assuming that its main battery remains in good health. An extended science phase using the rechargeable secondary battery may be possible, assuming Sun illumination conditions allow and dust settling on the solar panels does not prevent it. This extended phase could last until March 2015, after which conditions inside the lander are expected to be too hot for it to continue operating.

Science highlights from the primary phase will include a full panoramic view of the landing site, including a section in 3D, high-resolution images of the surface immediately underneath the lander, on-the-spot analysis of the composition of the comet’s surface materials, and a drill that will take samples from a depth of 23 cm and feed them to an onboard laboratory for analysis.

The lander will also measure the electrical and mechanical characteristics of the surface. In addition, low-frequency radio signals will be beamed between Philae and the orbiter through the nucleus to probe the internal structure.

The detailed surface measurements that Philae makes at its landing site will complement and calibrate the extensive remote observations made by the orbiter covering the whole comet.

“Rosetta is trying to answer the very big questions about the history of our Solar System. What were the conditions like at its infancy and how did it evolve? What role did comets play in this evolution? How do comets work?” said Matt Taylor, ESA Rosetta project scientist.

“Today’s successful landing is undoubtedly the cherry on the icing of a 4 km-wide cake, but we’re also looking further ahead and onto the next stage of this ground-breaking mission, as we continue to follow the comet around the Sun for 13 months, watching as its activity changes and its surface evolves.”

While Philae begins its close-up study of the comet, Rosetta must manoeuvre from its post-separation path back into an orbit around the comet, eventually returning to a 20 km orbit on 6 December.

Next year, as the comet grows more active, Rosetta will need to step further back and fly unbound ‘orbits’, but dipping in briefly with daring flybys, some of which will bring it within just 8 km of the comet centre.

The comet will reach its closest distance to the Sun on 13 August 2015 at about 185 million km, roughly between the orbits of Earth and Mars. Rosetta will follow it throughout the remainder of 2015, as they head away from the Sun and activity begins to subside.

“It’s been an extremely long and hard journey to reach today’s once-in-a-lifetime event, but it was absolutely worthwhile. We look forward to the continued success of the great scientific endeavour that is the Rosetta mission as it promises to revolutionise our understanding of comets,” said Fred Jansen, ESA Rosetta mission manager.

June 30, 2014

Ancient asteroid destroyer finally found, and it’s a new kind of meteorite

Filed under: Asteroids, Comets, Earth, Inner Solar System, Kuiper Belt, Oort Cloud — bferrari @ 8:56 am

Illustration of a meteor shower.argus/Shutterstock.com

For 50 years, scientists have wondered what annihilated the ancestor of L-chondrites, the roof-smashing, head-bonking meteorites that frequently pummel Earth.

Now, a new kind of meteorite discovered in a southern Sweden limestone quarry may finally solve the mystery, scientists report. The strange new rock may be the missing “other half” from one of the biggest interstellar collisions in a billion years.

“Something we didn’t really know about before was flying around and crashed into the L-chondrites,” said study co-author Gary Huss of the University of Hawaii at Manoa.

The space rock is a 470-million-year-old fossil meteorite first spotted three years ago by workers at Sweden’s Thorsberg quarry, where stonecutters have an expert eye for extraterrestrial objects. Quarriers have plucked 101 fossil meteorites from the pit’s ancient pink limestone in the last two decades. [Photos: New Kind of Meteorite Found in Sweden]

Researchers have nicknamed the new meteorite the “mysterious object” until its formal name is approved, said lead study author Birger Schmitz, of Lund University in Sweden and Chicago’s Field Museum. It will likely be named for a nearby church, the sterplana, he said.

Mysterious find

Geochemically, the meteorite falls into a class called the primitive achondrites, and most resembles a rare group of achondrites called the winonaites. But small differences in certain elements in its chromite grains set the mysterious object apart from the winonaites, and its texture and exposure age distinguish the new meteorite from the other 49,000 or so meteorites found so far on Earth.

“It’s a very, very strange and unusual find,” Schmitz told Live Science’s Our Amazing Planet.

The new meteorite was recently reported online in the journal Earth and Planetary Science Letters, and the study will appear in the journal’s Aug. 15 print edition.

Until now, all of the quarry’s fossil meteorites were L-chondrites. Schmitz, who has led the chondrite cataloging, admitted the rock hunt had become “quite boring.”

But the rare find has not only revitalized interest in the quarry, it has also brought together the world’s top meteorite experts for a global hunt through geologic time. Thanks to Schmitz’s careful detective work on meteorites, scientists now know that each kind of meteorite leaves behind a unique calling card: tough minerals called spinels. Even if meteorites weather away, their spinels linger for hundreds of million of years in Earth rocks. Schmitz and his cohorts think they can pin down how many meteorites rained down on Earth in the past 2.5 billion years, as well as what kind fell, by extracting extraterrestrial spinels from sedimentary rocks. Their work may confirm suspicions that recent meteorite falls represent a mere fraction of the rocks drifting in space.

“I think our new finding adds to the understanding that the meteorites that come down on Earth today may not be entirely representative of what is out there,” Schmitz said. “One thing our study shows is that we maybe don’t know as much as we think we know about the solar system.”

Ancient wreckage

The limestone quarry preserves the remnants of a cosmic cataclysm that took place 470 million years ago, during the Ordovician Period. Scientists think there was an enormous crash between two large bodies out in the asteroid belt. The crash blew apart two asteroids, or an asteroid and comet, slinging dust and debris toward Earth. One of the impactors was the source of all L-chondrite meteorites. But no one has ever found a piece of the rock that hit the L-chondrite parent, until now.

The Swedish meteorite’s exposure age the length of time it sailed through space is the key to placing the fossil space rock at the scene of the crash. The meteorite zipped from the asteroid belt to Earth in just 1 million years. That’s the same remarkably young exposure age as the L-chondrites recovered from the Thorsberg quarry, suggesting the rocks sprayed Earth in the same wave of space debris. [Infographic: Asteroid Belt Explained]

Meteorite expert Tim Swindle, who was not involved in the study, praised the team’s careful analysis and said it was unlikely that any other meteorite but an Ordovician fragment would have such a short exposure age. “Very, very few modern meteorites have exposure ages that low,” said Swindle, a professor at the University of Arizona in Tucson. “Typically, it takes things longer to get here from the asteroid belt,” he said. “It’s a telling argument.”

But because so little is left of the original meteorite almost all its minerals have been altered to clay Swindle thinks there’s wiggle room for linking it to known classes of meteorite, instead of calling it a new find.

“I think it’s entirely plausible [that it’s a new kind of meteorite], and it’s a great study, but that’s not a guarantee they’ve got it right,” Swindle said. “But if they didn’t, it’s because of new things we’ll find out in future work, not because of their analysis.”

The geochemical tests were performed on sand-sized chromite spinels, which confirmed the rock’s extraterrestrial origin. The altered clay is also about 100,000 times richer in iridium than terrestrial rocks. Iridium is the element that marks the meteorite impact horizon when the dinosaurs went extinct.

Hunt for space history

Schmitz now plans to search for these strange achondrite spinels in the quarry sediments, as well as in other rocks of the same age around the world. Ordovician meteorite spinels from L-chondrites have been found in China, Russia and Sweden, and small micrometeorites have been discovered in Scotland and South America. Researchers think about 100 times as many meteorites fell on Earth during the Ordovician compared with today, but only about a dozen impact craters of the proper age have been identified. [Crash! 10 Biggest Impact Craters on Earth]

A bigger quest is also in the works. Schmitz and his colleagues plan to dissolve tons of rock in acid in a global search for meteoritic spinel grains. This detective work will help researchers pin down the history of the asteroid belt and solar system. Spinels can provide an estimate of how many meteorites fell in the past, and what kind hit Earth. These tiny pieces of vanished meteorites may fill in missing history, because meteorite impact craters often vanish due to geologic forces.

“This can give you a ground truth for models for how the solar system may have evolved over time,” said Gary Huss, a co-author on the Swedish meteorite study who will collaborate on the spinel search. “I think a lot of people have worried for some time that we don’t really know what’s going on in the asteroid belt.”

Source

June 16, 2014

NASA’s real life Enterprise may take us to other star systems one day

Dr. Harold “Sonny” White is still working on a warp drive at NASA’s Johnson Space Center. His work is still in the experimental stage but that doesn’t mean he can’t imagine what the real lifeEnterprise ship would look like according to his math.

You’re looking at it right now.

..

 

This is the starship that may take us where no human has gone before. And it has me screaming like a little Klingon girl.

 

 

Concept 3D artist Mark Rademaker told io9 that “he worked with White to create the updated model, which includes a sleek ship nestled at the center of two enormous rings, which create the warp bubble.”

The updated model is the one you can see above, a variation of the original concept which, according to Dr. White, was rendered by Rademaker based on an idea by Matthew Jeffries, the guy who came with “the familiar Star Trek look.” This is the original warp drive spaceship concept:

Dr. White—whose daily life is working in future propulsion solutions for interplanetary travel in the near future, like ion and plasma thrusters—developed new theoretical work that solved the problems of the Alcubierre Drive concept, a theory that allowed faster-than-light travel based on Einstein’s field equations in general relativity, developed by theoretical physicist Miguel Alcubierre.

A spaceship equipped with a warp drive would allow faster-than-light travel by bending the space around it, making distances shorter. At the local level, however, the spaceship wouldn’t be moving faster than light. Therefore, warp drive travel doesn’t violate the first Einstein commandment: Thou shall not travel faster than light.

Not a fantasy, but real science

But Interstellar is just science fiction. Dr. White’s work at the Advanced Propulsion Theme Lead for the NASA Engineering Directorate is science. And while his department only gets peanuts compared to NASA’s budget (not to talk about the Pentagon’s) I find his words comforting:

Perhaps a Star Trek experience within our lifetime is not such a remote possibility.

See, Dr. White and his colleagues aren’t making a movie or coming up with 3D renders for the sake of it. They just don’t just believe a real life warp drive is theoretically possible; they’ve already started the work to create one:

Working at NASA Eagleworks—a skunkworks operation deep at NASA’s Johnson Space Center—Dr. White’s team is trying to find proof of those loopholes. They have “initiated an interferometer test bed that will try to generate and detect a microscopic instance of a little warp bubble” using an instrument called the White-Juday Warp Field Interferometer.

It may sound like a small thing now, but the implications of the research huge. In his own words:

Although this is just a tiny instance of the phenomena, it will be existence proof for the idea of perturbing space time-a “Chicago pile” moment, as it were. Recall that December of 1942 saw the first demonstration of a controlled nuclear reaction that generated a whopping half watt. This existence proof was followed by the activation of a ~ four megawatt reactor in November of 1943. Existence proof for the practical application of a scientific idea can be a tipping point for technology development.

The roadmap to the warp drive

According to Dr. White, this is a roadmap that they need to follow to achieve that final objective of rapid interstellar travel.

Every time I read that paragraph I smile—and these renders just make my smile so wide it looks stupid.

OK, Dr. White, you got our attention. Make it so.

Source

May 28, 2014

21-year-old makes astronomy breakthrough

Filed under: Black Holes, Cool, Cosmology, Outer Solar System — bferrari @ 11:53 am
This stock photo shows a dense swarm of stars. (AP PHOTO/NASA-ESA)

This stock photo shows a dense swarm of stars. (AP PHOTO/NASA-ESA)

At just 21 years old, a California college student has made an incredible discovery: Michael Sandoval and his astrophysics professor at San Jose State have spotted what they believe is one galaxy that was swallowed up by another.

The result is a dense system of stars—apparently the densest ever found. They’re calling it a “hypercompact cluster,” since no word for the object currently exists, theSan Jose Mercury News reports.

The finding occurred as Sandoval took the first course he’d ever taken on the subject, NBC Bay Area reports. “Some people take years and never find” such space phenomena, says astrophysics professor Aaron Romanowsky.

Sandoval took about a week to find it, inspired by the work of a classmate who’d found what had previously appeared to be the densest known bunch of stars.

To make the story even more impressive, Sandoval’s find came as he grieved for his mother, who died in October. He’d been living at home in recent years to take care of her during an illness, sometimes having to take her to the ER before heading to class the next day.

“I didn’t want to be sitting home, feeling sorry for myself,” Sandoval says. “That’s not what she would have wanted, anyway.” (Another recent space discovery involves an ancient space collision.)

Source

October 9, 2013

Meet the asteroid that might hit Earth in 2880

Radar image of 1950 DA acquired by the Arecibo Observatory on March 4, 2001. (NASA/JPL/S. OSTRO)

Radar image of 1950 DA acquired by the Arecibo Observatory on March 4, 2001. (NASA/JPL/S. OSTRO)

There are over 10,000 near-Earth objects (NEOs) that have been identified so far — asteroids and comets of varying sizes that approach the Earth’s orbital distance to within about 28 million miles. Of the 10,000 discoveries, roughly 10 percent are larger than six-tenths of a mile in size — large enough to have disastrous global consequences should one impact the Earth.

This is one of them.

First discovered in February 1950, 1950 DA is a 1.1-kilometer-wide asteroid that was observed for 17 days and then disappeared from view. Then it was spotted again on Dec. 31, 2000 — literally on the eve of the 21st century. Coupled with radar observations made a few weeks later in March 2001 it was found that, along with a rather high rotation rate (2.1 hours), asteroid 1950 DA has a trajectory that will bring it very close to Earth on March 16, 2880. How close? Close enough that, within a specific 20-minute window, a collision can not be entirely ruled out.

Top 10 Ways to Stop an Asteroid

The image above was made from radar observations by the Arecibo Observatory in Puerto Rico in March 2001, when 1950 DA passed within 4.8 million miles of Earth. Is this the mug shot of a future continent-killer?

Radar analysis and research of 1950 DA performed by NASA’s Jet Propulsion Laboratory scientists J.D. Giorgini, S. J. Ostro, Don Yeomans and several others from JPL and other institutions revealed that the impact probability from 1950 DA in March 2880 is, at most, 1 in 300 based on what is known about the asteroid so far.

1 in 300 may sound like a slim chance, but actually this represents a risk 50% greater than that of the average hazard due to all other asteroids from now to then.

However, that’s a maximum value. The study also noted the collision probability for 1950 DA as being in the range from 0 to 0.33%. That upper limit could increase or decrease as more is learned about the asteroid. (The next opportunity for studying 1950 DA via radar is in 2032.)

There are many factors that influence the path of an asteroid through space. Its spin rate, reflectivity (albedo), composition, mass, terrain variations… gravitational interactions with other bodies, some of which may not even have been discovered yet… all of these can affect the movement of an asteroid and, more specifically, its exact position at a future point in time. While many of these things still aren’t precisely known for 1950 DA, one in particular could end up being the saving grace for our descendants: the Yarkovsky effect.

PHOTOS: Russian Meteor Strike Aftermath

A small but important force acting upon asteroids, the Yarkovsky effect is a “nudge” created by thermal emission. As an asteroid gathers heat energy from the sun, it releases some of that energy back into space. Thanks to Newtonian mechanics the sheer act of doing so creates a physical push back on the asteroid itself, altering its course ever so slightly. Over a long span of time, this slight alteration could result in the relocation of 1950 DA away from the spot in space where Earth will be on March 16, 2880… at least enough so that a miss is certain.

In fact, recent research by JPL scientists D. Farnocchia and S.R. Chesley have taken into consideration the Yarkovsky effect on 1950 DA based on known values from previous observations, as well as new research suggesting that the asteroid has a retrograde rotation. While their latest assessment does put the risk of an impact in 2880 within the lower end of the probability spectrum (4×10^-4, or -0.58 on the Palermo Scale) it is still far from zero, and in fact remains higher than any other known potential impacts.

PHOTOS: NASA’s Asteroid Capture Mission

So what would happen if the half-mile-wide 1950 DA were to hit Earth? While that depends on a lot of things, such as its composition, speed, angle of impact, where it impacts, etc., needless to say it would cause a lot of damage across a large area. I’m talking an energy release upwards of half a million megatons, which, were it to strike say, New York City, everything within at least a 100-mile radius would be flattened by the force of the impact alone — that’s halfway to Boston and Washington, DC. And that’s not even taking into consideration the air blast, atmospheric dust cloud, secondary impacts from debris, or damage from any resulting tsunami (if the impact were in the ocean)… the destruction would easily extend out many more hundreds of miles, and the repercussions — physical, financial, economic, and emotional — would extend around the globe.

But again, precisely where 1950 DA will be in another 866 1/2 years (and whether or not it will occupy the same point in space as our planet) relies on many factors that aren’t well known — even though its orbit is pretty well understood. More in-depth observations will need to be made, and that is why asteroids like this must be carefully — and continually — watched.

Luckily, 35 generations offers plenty of time to improve our knowledge. According to JPL’s Near-Earth Object program, “If it is eventually decided 1950 DA needs to be diverted, the hundreds of years of warning could allow a method as simple as dusting the surface of the asteroid with chalk or charcoal, or perhaps white glass beads, or sending a solar sail spacecraft that ends by collapsing its reflective sail around the asteroid. These things would change the asteroids reflectivity and allow sunlight to do the work of pushing the asteroid out of the way.”

ANALYSIS: Meet Asteroid 2013 MZ5, 10,000th Near-Earth Object

Still, whether because of ongoing research, faith in future generations of scientists, or just sheer probability, JPL remains confident that 1950 DA should cause little concern. “The most likely result will be that St. Patrick’s Day parades in 2880 will be a little more festive than usual as 1950 DA recedes into the distance, having passed Earth by.”

Let’s just hope the luck of the Irish is with our planet big time that year…

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January 9, 2013

Asteroid Apophis to whiz past Earth tonight — and return for more in 2036

An artist's rendering of the asteroid Apophis. (European Space Agency)

An artist’s rendering of the asteroid Apophis. (European Space Agency)

A European space telescope has captured new images of the huge asteroid Apophis, revealing that the potentially hazardous object is actually bigger than previously thought — and you have a chance to see the space rock yourself in two free webcasts tonight.

Asteroid Apophis has long been billed as a “doomsday asteroid” because of a 2004 study that predicted a 2.7 percent chance of the space rock hitting Earth when it passes within 22,364 miles of the planet in April 2029, European Space Agency officials said. Later studies proved, however, that the asteroid poses no threat to Earth during that flyby, but astronomers continue to track the object since it will make another pass near Earth in 2036.

 

Today, ESA officials announced that its infrared Herschel Space Observatory has discovered that Apophis is about 1,066 feet wide, nearly 20 percent larger than a previous estimate of 885 feet.

“The 20 percent increase in diameter … translates into a 75 percent increase in our estimates of the asteroid’s volume or mass,” study leader Thomas Müller of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, said in a statement. [Photos of Near-Earth Asteroid Apophis]

‘Alone among all these near-Earth asteroids that have passed our way in recent years, Apophis has generated the most concern worldwide.’

– Slooh president Patrick Paolucci

Tonight’s two free webcasts will stream live views of Apophis from telescopes in Italy and the Canary Islands tonight (Jan. 10). The webcasts, offered by the stargazing websites Slooh Space Telescope and Virtual Telescope Project, will show Apophis as a bright light moving across the night sky. The asteroid is too small to be seen through small backyard telescopes.

The Slooh Space Camera webcast will begin at 7 p.m. EST (0000 Jan. 10 GMT). The Virtual Telescope webcast will begin an hour later at 8 p.m. EST (0100 GMT). You can watch both live webcasts of asteroid Apophis here on SPACE.com tonight.

Apophis will be just under 9.3 million miles from Earth at the time of tonight’s webcasts, amateur astronomer Gianluca Masi of the Virtual Telescope Project told SPACE.com.

“Alone among all these near-Earth asteroids that have passed our way in recent years, Apophis has generated the most concern worldwide because of its extremely close approach in 2029 and [chances of a] potential impact, albeit small, in 2036,” Slooh president Patrick Paolucci said in a statement.

In addition to asteroid Apophis, astronomers regularly scan the night sky for asteroids  that may pose a potential impact threat to Earth. NASA’s Near-Earth Object Office and Asteroid Watch program is based at the agency’s Jet Propulsion Laboratory in Pasadena, Calif.

You can track Apophis directly via the Virtual Telescope Project here: http://www.virtualtelescope.eu/webtv/

The webcast from the Slooh Space Camera can also be seen here: http://events.slooh.com/
Source

December 3, 2012

At far side of solar system, Voyager 1 discovers new region of space

Filed under: Cool, Cosmology, Gadgets, Outer Solar System, Space Exploration, Space Ships — bferrari @ 8:56 pm

NASA's Voyager 1 spacecraft is currently exploring a new region in our solar system called the

It keeps going … and going … and going ….

NASA’s Voyager 1 spacecraft, launched in 1977 and now the most distant human-made object from the sun, at about 11 billion miles, has entered a new region at the edge of the solar system it is close to exiting forever.

Scientists have dubbed this region the “magnetic highway” and it’s the last stop before interstellar space, or the space between stars.

“Although Voyager 1 still is inside the sun’s environment, we now can taste what it’s like on the outside because the particles are zipping in and out on this magnetic highway,” said Edward Stone, Voyager project scientist based at the California Institute of Technology, Pasadena. “We believe this is the last leg of our journey to interstellar space. Our best guess is it’s likely just a few months to a couple years away.”

“The new region isn’t what we expected, but we’ve come to expect the unexpected from Voyager.”

The findings were presented Monday at a meeting of the American Geophysical Union meeting in San Francisco.

“We are in a magnetic region unlike any we’ve been in before — about 10 times more intense than before the termination shock — but the magnetic field data show no indication we’re in interstellar space,” said Leonard Burlaga, a Voyager magnetometer team member based at NASA’s Goddard Space Flight Center in Greenbelt, Md.

Voyager 1 and its twin Voyager 2 launched 35 years ago on a tour of the outer planets. Afterward, both spacecraft continued to hurtle toward the fringes of the solar system.

Mission chief scientist Ed Stone says it’s unknown when Voyager 1 will finally break through to interstellar space. Once that happens, it’ll be the first manmade object to leave the solar system.

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