A Hypervelocity star in the center of the image. Click for larger. Credit: NASA, ESA, O. Gnedin (University of Michigan, Ann Arbor), and W. Brown (Harvard-Smithsonian Center for Astrophysics, Cambridge, Mass.)

This is very strange, this star was ejected from our galaxy and is traveling at about 1,600,000 miles per hour — that’s 2,500,000 km/hr !! Of the 16 known hypervelocity stars this is the fastest. To add to the strangeness this star also should have burned out long-long ago but yet we can still see it.

Read how it came to be ejected, how it got going so fast and why we can still see it with Hubble in the Hubble press release, you can also visit Hubblesite to see more images:

A hundred million years ago, a triple-star system was traveling through the bustling center of our Milky Way galaxy when it made a life-changing misstep. The trio wandered too close to the galaxy’s giant black hole, which captured one of the stars and hurled the other two out of the Milky Way. Adding to the stellar game of musical chairs, the two outbound stars merged to form a super-hot, blue star.

This story may seem like science fiction, but astronomers using NASA’s Hubble Space Telescope say it is the most likely scenario for a so-called hypervelocity star, known as HE 0437-5439, one of the fastest ever detected. It is blazing across space at a speed of 1.6 million miles (2.5 million kilometers) an hour, three times faster than our Sun’s orbital velocity in the Milky Way. Hubble observations confirm that the stellar speedster hails from the Milky Way’s core, settling some confusion over where it originally called home.

Most of the roughly 16 known hypervelocity stars, all discovered since 2005, are thought to be exiles from the heart of our galaxy. But this Hubble result is the first direct observation linking a high-flying star to a galactic center origin.

“Using Hubble, we can for the first time trace back to where the star comes from by measuring the star’s direction of motion on the sky. Its motion points directly from the Milky Way center,” says astronomer Warren Brown of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., a member of the Hubble team that observed the star. “These exiled stars are rare in the Milky Way’s population of 100 billion stars. For every 100 million stars in the galaxy lurks one hypervelocity star.”

The movements of these unbound stars could reveal the shape of the dark matter distribution surrounding our galaxy. “Studying these stars could provide more clues about the nature of some of the universe’s unseen mass, and it could help astronomers better understand how galaxies form,” says team leader Oleg Gnedin of the University of Michigan in Ann Arbor. “Dark matter’s gravitational pull is measured by the shape of the hyperfast stars’ trajectories out of the Milky Way.”

The stellar outcast is already cruising in the Milky Way’s distant outskirts, high above the galaxy’s disk, about 200,000 light-years from the center. By comparison, the diameter of the Milky Way’s disk is approximately 100,000 light-years. Using Hubble to measure the runaway star’s direction of motion and determine the Milky Way’s core as its starting point, Brown and Gnedin’s team calculated how fast the star had to have been ejected to reach its current location.

“The star is traveling at an absurd velocity, twice as much as the star needs to escape the galaxy’s gravitational field,” explains Brown, a hypervelocity star hunter who found the first unbound star in 2005. “There is no star that travels that quickly under normal circumstances — something exotic has to happen.”

There’s another twist to this story. Based on the speed and position of HE 0437-5439, the star would have to be 100 million years old to have journeyed from the Milky Way’s core. Yet its mass — nine times that of our Sun — and blue color mean that it should have burned out after only 20 million years — far shorter than the transit time it took to get to its current location.

The most likely explanation for the star’s blue color and extreme speed is that it was part of a triple-star system that was involved in a gravitational billiard-ball game with the galaxy’s monster black hole. This concept for imparting an escape velocity on stars was first proposed in 1988. The theory predicted that the Milky Way’s black hole should eject a star about once every 100,000 years.

Brown suggests that the triple-star system contained a pair of closely orbiting stars and a third outer member also gravitationally tied to the group. The black hole pulled the outer star away from the tight binary system. The doomed star’s momentum was transferred to the stellar twosome, boosting the duo to escape velocity from the galaxy. As the pair rocketed away, they went on with normal stellar evolution. The more massive companion evolved more quickly, puffing up to become a red giant. It enveloped its partner, and the two stars spiraled together, merging into one superstar — a blue straggler.

“While the blue straggler story may seem odd, you do see them in the Milky Way, and most stars are in multiple systems,” Brown says.

This vagabond star has puzzled astronomers since its discovery in 2005 by the Hamburg/European Southern Observatory sky survey. Astronomers had proposed two possibilities to solve the age problem. The star either dipped into the Fountain of Youth by becoming a blue straggler, or it was flung out of the Large Magellanic Cloud, a neighboring galaxy.

In 2008 a team of astronomers thought they had solved the mystery. They found a match between the exiled star’s chemical makeup and the characteristics of stars in the Large Magellanic Cloud. The rogue star’s position also is close to the neighboring galaxy, only 65,000 light-years away. The new Hubble result settles the debate over the star’s birthplace.

Astronomers used the sharp vision of Hubble’s Advanced Camera for Surveys to make two separate observations of the wayward star 3 1/2 years apart. Team member Jay Anderson of the Space Telescope Science Institute in Baltimore, Md., developed a technique to measure the star’s position relative to each of 11 distant background galaxies, which form a reference frame.

Anderson then compared the star’s position in images taken in 2006 with those taken in 2009 to calculate how far the star moved against the background galaxies. The star appeared to move, but only by 0.04 of a pixel (picture element) against the sky background. “Hubble excels with this type of measurement,” Anderson says. “This observation would be challenging to do from the ground.”

The team is trying to determine the homes of four other unbound stars, all located on the fringes of the Milky Way.

“We are targeting massive ‘B’ stars, like HE 0437-5439,” says Brown, who has discovered 14 of the 16 known hypervelocity stars. “These stars shouldn’t live long enough to reach the distant outskirts of the Milky Way, so we shouldn’t expect to find them there. The density of stars in the outer region is much less than in the core, so we have a better chance to find these unusual objects.”

The results were published online in The Astrophysical Journal Letters on July 20, 2010. Brown is the paper’s lead author.

“Sleepwalkers have been described to be involved in complex motor activities like cooking, eating, driving a car, playing an instrument, stabbing and murder [1]. We describe a case of a 44-year-old woman with idiopathic insomnia almost all her life. She tried various medications, psychotherapy and behavioral techniques for the treatment of her insomnia without any significant effects. She was started on Zolpidem 10 mg 4 years ago. She was able to sleep 4–5 h each night, but then the effects started wearing off. She increased the dose of Zolpidem by herself to 15 mg every night; she would take 10 mg tablet around 10 p.m. and 5 mg around 3 a.m. With this regimen she started sleeping for 5 h every night and felt alert during the daytime. After increasing the dose, she began to have episodes of sleepwalking. During one such episode, she went to bed around 10 p.m., she woke up 2 h later, and walked to the next room on the same floor. She turned on the computer and connected to the internet. She logged in by typing her user ID and password to her email account. She sent three emails to her friend inviting her to come over for dinner and drinks (Fig. 1A and B). Her friend called her the next day to accept the invitation. She said that the emails had strange language. The patient was not aware of these emails. She checked her sent folder and found three emails sent at 11:47 p.m., 11:50 p.m. and 11:53 p.m. They were in upper and lower cases, not well formatted and had strange language. She was shocked when she saw these emails, as she did not recall writing them. She did not have any history of night terrors or sleepwalking as a child. Her overnight video polysomnogram did not capture any episode and was normal. She was advised to reduce her dose of Zolpidem; after which she did not have any more episodes of sleepwalking.”

Bonus Figure:

Fig. 1. (A) Emails written by patient during an episode of sleepwalking. (B) Emails written by the same patient three minutes after the first e-mail (A) during an episode of sleepwalking.

Photo: flickr/Ingorrr

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Discoblog: NCBI ROFL: Then how come I still check my email every 5 minutes?
Discoblog: NCBI ROFL: The case of “Judge Nodd” and other sleeping judges–media, society, and judicial sleepiness.
Discoblog: NCBI ROFL: Sleep disturbances in Disney animated films.

WTF is NCBI ROFL? Read our FAQ!

Well, Darlene’s last guest post went stratospheric on Digg, and we are still reeling from the traffic. For some strange reason–having to do with the bizarre combination of “Tom Johnson,” a list of “sexy” scientists, and now this–this July we are on track to break our all time traffic record from precisely a year ago, when everybody was debating Unscientific America.

Thanks, Darlene. Or, to paraphrase the original title of your post:

“Who gets the credit for the BP Container Cap post? Darlene Does.”

Looking at a planetary nebula 6,500 light years away, scientists recognized an old friend: the buckyball. The large, soccer ball-shaped molecule–made from bonding 60 carbon atoms together–was first seen in a lab in 1985. In a paper published today in Science, scientists confirm the first known extraterrestrial existence of the rare carbon balls.

The buckyballs’ planetary nebula, called TC 1, surrounds a white dwarf star. Using NASA’s Spitzer Space Telescope, a team led by Jan Cami of the University of Western Ontario observed traces of the the 60-atom balls and their 70-atom cousins while looking at light coming from the white dwarf.

When light hits molecules and atoms, they will vibrate in specific, measurable ways–a field of science known as spectroscopy. One of Cami’s colleagues, who was studying Tc 1, found some unfamiliar fingerprints in the nebula’s infrared light. Cami recognized them as carbon’s 60-atom configuration and its favored 70-atom carbon partner. [Discovery News]

The researchers think a lack of hydrogen in this nebula allowed the formation of the buckyballs, known more generally as fullerene (named after architect Buckminster Fuller and his geodesic domes).

The team suspects that abundant carbon and a lack of hydrogen in the nebula created just the right environment to give rise to buckyballs. When hydrogen is present, it combines with carbon, preventing the pure-carbon spheres from forming. [New Scientist]

The spherical version of the carbon molecule has found many applications in chemistry and physics research, for example, in building nanostructures. Researchers suspect that the balls, given their temperature, formed within the past 100 years, but may be impossible to make out a century from now.

The finding “shows that complex, large molecules can exist in space,” said astrophysicist Theodore Snow of the University of Colorado in Boulder, who was not involved in the research. “Buckyballs are very stable and resistant to interstellar ultraviolet radiation, so once formed they can have long lifetimes in space.” [SPACE.com]

Sir Harry Kroto, who won a Nobel Prize in Chemistry for discovering buckyballs, waxed poetic about their interstellar presence, wondering if there might be buckyball leftovers in each of us.

“It’s so beautiful that it’s been hiding from us and it took an experiment trying to uncover what was going on in stars to find it…. All the carbon in your body came from star dust, so at one time some that carbon may have been in the from of buckyballs.” [BBC]

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Image: Artist’s rendition / NASA/JPL-Caltech

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Let’s say you’re a peat moss plant. Since you’re stuck in one place, and it’s low to the ground where there’s little wind or air turbulence, you have to find a way to shoot your spores way up into the air where they can be dispersed.

In reality, mosses have conquered this problem by shooting their spores into the sky at speeds of greater than 30 meters (nearly 100 feet) per second. Their spherical capsules containing the spores deform inward until the pressure forces a ferocious explosion to propel spores at that velocity. But even this is not enough—air would slow the spores before they reached a high enough height to get carried away.

Luckily, Dwight Whitaker and Joan Edwards found that the moss plants have another trick, which they published in the journal Science. After shooting video at 100,000 frames per second, the scientists saw that the plants shoot their spores in a vortex ring, like a tiny mushroom cloud or a smoke ring. The fluid dynamics of the vortex rings allow it to carry those spores through the air much farther than they could travel without it.

For plenty more about this, read Ed Yong’s post at Not Exactly Rocket Science. But first, watch this short video the researchers made.

Related Content:
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The Loom: Fungus Opera

Video: Clara Hard, Joan Edwards, Dwight Whitaker