How Big is the Milky way?

[MIKA27]

When this star dies it will leave one hell of a black hole!!

Just add it to the list that are already out there!

[OZCUBAN]

Just add it to the list that are already out there!

One hell of a black hole and a kick ass supernova,complete with a huge shock wave ,you would not want to be any where near it ,the more light years the better

[OZCUBAN]

Hyperfast Star Was Booted From Milky Way

This illustration shows one possible mechanism for how the star HE 0437-5439 acquired enough energy to be ejected from our Milky Way galaxy. In this scenario, a triple-star system, consisting of a close binary system and another outer member bound to the group, is orbiting near the galaxy's monster black hole. One star is captured by the black hole and the tightly bound pair gets ejected from the galaxy. As the duo speeds through the galaxy, one member evolves more quickly and consumes the other. The resulting rejuvenated star, massive and very blue, is called a blue straggler.

Credit: NASA, ESA, and A. Feild (STScI)

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.

The hot, blue star HE 0437-5439 has been tossed out of the center of our Milky Way galaxy with enough speed to escape the galaxy's gravitational clutches. The stellar outcast is rocketing through the Milky Way's distant outskirts at 1.6 million miles an hour, high above the galaxy's disk, about 200,000 light-years from the center. The star is destined to roam intergalactic space.

Credit: NASA, ESA, and G. Bacon (STScI)

Compass/Scale Image of Hypervelocity Star HE 0437-5439

Credit: NASA, ESA, and Z. Levay (STScI)

Location of Hypervelocity Star HE 0437-5439

Credit: NASA, ESA, and Z. Levay (STScI) 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.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI) conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc. in Washington, D.C.

OZ

Truly amazing stuff,the power of the universe

[MIKA27]

Solar fireworks set to follow sun blast

A WAVE of violent space weather has begun rolling over the Earth after a huge explosion on the sun.

Scientists say the wave of supercharged gas should buffet the natural magnetic shield protecting the Earth, possibly sparking spectacular displays of the auroras known as the northern and southern lights.

The explosion - which occurred three days ago and was aimed directly at the Earth - was recorded by several satellites, including NASA's new Solar Dynamics Observatory, which watched its shock wave rippling outwards.

It covered the entire Earth-facing side of the sun and sent a "solar tsunami" racing across space at up to 1.5 million km/h, according to NASA.

Astronomers from all over the world witnessed the huge flare above a giant sunspot the size of the Earth.

They're at this moment watching for signs of the northern lights extending as far south as northern USA and the UK.

In the southern hemisphere, viewers on the South Island of New Zealand and possibly those in Tasmania may have caught the show last night, which is expected to continue tonight.

"If you're lucky, people in Tasmania would have the best chance of seeing a reddish glow to skies looking south," Glen Nagle, from the Canberra Deep Space Communication Complex, told ninemsn.

In the north, www.examiner.com is reporting that instruments aboard NASA’s GOES-13 satellite have begun recording the effects of the storm, while the NOAA / USGS magnetometer in Boulder, Colorado, has seen heightened activity in the last few hours.

Such solar fireworks have the potential to hit power grids and communications satellites, such as the blast which is alleged to have knocked out Galaxy 13 on April 3, creating the drifting "Zombie Satellite".

Britain's Daily Telegraph disclosed in June that senior space agency scientists believed the Earth would be hit with unprecedented levels of magnetic energy from solar flares after the sun woke from a deep slumber about 2013.

The last major flare-up occurred in 2001 and the sun has been going through a strangely prolonged period of silence, including an virtually incident-free past two years.

MIKA: This can potentially cause a major global issue with unshielded satellites etc.

The solar storm of 1859, also known as the Solar Superstorm,or the Carrington Event,was the most powerful solar storm in recorded history. Here's a link from a 2003 report on the 1859 event called THE GREAT STORM:

[OZCUBAN]

Great posts mika

Wow lets hope the worlds power and telecommunications stay intact

[OZCUBAN]

Spacecraft Observes Coronal Mass Ejection

One of the fastest CMEs in years was captured by the STEREO COR1 telescopes on August 1, 2010. This movie, combining COR1-Ahead images with the simultaneous Helium II 304 Angstrom images from the STEREO EUVI telescope, shows the rapid explosion of material outward, followed by a slower eruption of a polar crown prominence from another part of the Sun. This CME is seen to be heading towards Earth at speeds well over 1000 kilometers per second. Credit: NASA/STEREO

On August 1st, the sun emitted a C-class solar flare that spawned what scientists call a coronal mass ejection, or CME, headed toward Earth. The CME impacted Earth's magnetic field August 3rd. CMEs occasionally hit Earth. This CME will have few noticeable consequences beyond producing an aurorae.

The CME hit Earth's magnetic field on August 3rd at 1740 UT. The impact sparked a G2-class geomagnetic storm that lasted nearly 12 hours--time enough for auroras to spread all the way from Europe to North America. The possible arrival of a second CME on August 4th might provide even better spectacular auroral displays.

CMEs are large clouds of charged particles that are ejected from the sun over the course of several hours and can carry up to ten billion tons of plasma. They expand away from the sun at speeds as high as a million miles an hour. A CME can make the 93-million-mile journey to Earth in just two to four days. Stronger solar storms could cause adverse impacts to space-based assets and technological infrastructure on Earth.

The sun goes through a regular activity cycle about 11 years long. The last solar maximum occurred in 2001 and its recent extreme solar minimum was particularly weak and long lasting. These kinds of eruptions are one of the first signs that the sun is waking up and heading toward another solar maximum expected in the 2013 time frame.

> View larger http://www.nasa.gov/images/content/473058m...ldisruption.jpg

On August 1st, almost the entire Earth-facing side of the sun erupted in a tumult of activity. There was a C3-class solar flare, a solar tsunami, multiple filaments of magnetism lifting off the stellar surface, large-scale shaking of the solar corona, radio bursts, a coronal mass ejection and more. This extreme ultraviolet snapshot from the Solar Dynamics Observatory (SDO) shows the sun's northern hemisphere in mid-eruption. Different colors in the image represent different gas temperatures ranging from ~1 to 2 million degrees K. Credit: NASA/SDO

> View video of these events taken by SDO http://www.nasa.gov/multimedia/videogaller...dia_id=16939864

> View larger http://www.nasa.gov/images/content/472124m...0108002-cme.jpg

These images taken by the STEREO Ahead satellite from 3:47 to 15:47 UT on August 2nd show the movement of the CME cloud, on the right of the disc, as it expands toward Earth. Credit: NASA/STEREO

OZ WOW

[MIKA27]

Spacecraft Observes Coronal Mass Ejection

OZ WOW

Imagine the sheer power of that explosion, would disintegrate Earth.

[MIKA27]

Hubble releases beautiful spiral galaxy image

Hubble space telescope astronomers unveiled a look at a spiral galaxy spinning like a wheel amid a sea of stars on Tuesday.

The NGC 4911 galaxy lies some 320 million light-years away in the "Coma Cluster" of about 1,000 galaxies, islands of stars like our own Milky Way, set amid the vastness of space. One light year is about 5.9 trillion miles.

"In the case of NGC 4911, wispy arcs of the galaxy's outer spiral arms are being pulled and distorted by forces from a companion galaxy (NGC 4911A), to the upper right. The resultant stripped material will eventually be dispersed throughout the core of the Coma Cluster, where it will fuel the intergalactic populations of stars and star clusters," says a Hubble team statement.

The "natural-color" image combines data from 2006, 2007, and 2009 Hubble looks at the galaxy cluster.

[MIKA27]

Beer microbes live 553 days outside International Space Station (ISS)

Professor Charles Cockell from the OU explains how the experiment worked

A small English fishing village has produced an out-of-this-world discovery.

Bacteria taken from cliffs at Beer on the South Coast have shown themselves to be hardy space travellers.

The bugs were put on the exterior of the space station to see how they would cope in the hostile conditions that exist above the Earth's atmosphere.

And when scientists inspected the microbes a year and a half later, they found many were still alive.

These survivors are now thriving in a laboratory at the Open University (OU) in Milton Keynes.

The experiment is part of a quest to find microbes that could be useful to future astronauts who venture beyond low-Earth orbit to explore the rest of the Solar System.

OU researcher Dr Karen Olsson-Francis told BBC News: "It has been proposed that bacteria could be used in life-support systems to recycle everything.

"There is also the concept that if we were to develop bases on the Moon or Mars, we could use bacteria for 'bio-mining' - using them to extract important minerals from rocks."

This type of research also plays into the popular theory that micro-organisms can somehow be transported between the planets in rocks - in meteorites - to seed life where it does not yet exist.

OU-20: Single cells (left) at the centre of a colony (right) would get extra protection

The Beer microbes were placed on the European Space Agency's (Esa) Technology Exposure Facility, a collection of experimental boxes at the end of the International Space Station's (ISS) Columbus Laboratory.

The bacteria were sent up still sitting on, and in, small chunks of cliff rock.

They would have been exposed to extreme ultraviolet light, cosmic rays, and dramatic shifts in temperature.

All the water in the limestone would also have boiled away into the vacuum of space.

Quite how they managed to come through their 553-day ordeal is now being investigated.

Bacterial spores have been known to endure several years in orbit but this is the longest any cells of cyanobacteria, or photosynthesising microbes, have been seen to survive in space.

The bugs have been classified simply as OU-20. However, they resemble closely a group of cyanobacteria known as Gloeocapsa.

They have a thick cell wall and this could be part of the reason they survived so long in space.

"Gloeocapsa forms a colony of multiple cells that probably protects cells in the centre to exposure from UV radiation and provides some desiccation resistance as well," explained Professor Charles Cockell, who works with Dr Olsson-Francis in the OU's Planetary and Space Sciences Research Institute.

"The ones we have are related to Antarctic species but they're also generally quite well-known in hot deserts. So, as well as the colony-forming habit, I suspect they've got quite good DNA-repair processes, too."

When the OU team despatched the Beer rock to the station, all it knew was that the cliff material contained communities of different bacteria. The scientists had no idea which, if any, would make it back to the ground alive.

Exposure on the platform therefore worked like a screen, identifying bugs likely to have special properties.

"We could send up the spores of known 'extremophiles' and we can be pretty sure they will survive because we know already they're really resistant," Dr Olsson-Francis told BBC News.

"Whereas in this case, we just used a community to select for these organisms. These are just everyday organisms that live on the coast in Beer in Devon and they can survive in space."

The Beer rock was launched to the ISS in 2008. More cliff material was also put on a much shorter space exposure experiment lasting 10 days the previous year. Called Biopan-6, it was lofted by the Russians.

OU-20 came through that challenge, too.

Biopan-6 was the experiment famously survived by a group of "water bears". These tiny invertebrates hold the record for the longest-lived animals in open space.

[MIKA27]

Astronomers find new planet that could support life

Astronomers unveiled a new candidate Wednesday in their search for an Earth-like planet outside our solar system in a "habitable" zone, one just right for conditions that could support life.

"This is the most Goldilocks planet yet found," says team co-leader Paul Butler of the Carnegie Institution of Washington (D.C.) "Not too hot for liquid water, and not too cold."

Dubbed Gliese 581g, the planet is about 120 trillion miles away, circling a red dwarf star, according to a forthcoming report in The Astrophysical Journal. One face of the world is gravitationally locked to face its star, trapped in perpetual sunlight with the far side in perpetual darkness, says the report. Impossible to determine with present telescopes, life there would enjoy a permanent sunset (or sunrise) in a ring stretching from pole to pole, says study co-leader Steven Vogt of the University of California-Santa Cruz.

Smaller than our sun, the star Gliese 581 has five other planets beside Gliese 581g, which has a "year" of just under 37 days for each orbit of its star. All six planets were discovered through observations of the back-and-forth gravitational wobbles they induce on the star, as were most of the roughly 400 planets that have been detected orbiting nearby stars since 1995. Astronomers have reported other planets in the "habitable" zones of their stars since then, but Gliese 581g looks like the best fit yet for a place where life as we know it would thrive.

"It would be a great planet if you liked sunsets," says MIT planetary scientist Sara Seager, who was not part of the study. "What's exciting is this one turned up so close, and so soon, which means there must be many more."

Based on star surveys and similar discoveries of multiple planet solar systems nearby, Vogt estimates that 20 to 40 billion worlds orbit the habitable zones of their stars in our Milky Way galaxy.

Vogt argues that life likely has sprung up on at least some of these planets if they have oceans. But Seager cautions that, "any talk of life on Gliese 581g is pure speculation."

Assuming Gliese 581g has an atmosphere, average surface temperatures there would range from -24 to 10 degrees Fahrenheit. High altitude winds, Vogt says, would moderate hotter temperatures on the sunny side and frigid ones on the dark side. Surface winds, meanwhile, would rarely exceed 40 mph. The planet is about 1.2 to 1.4 times wider than Earth, with slightly stronger gravity.

In the last decade, astronomers have described the atmospheres of large "transit" planets with orbits viewable edge-on from Earth. Gliese 581g is not a transit planet, but NASA's Kepler spacecraft may reveal Earth-like worlds suited for such observations within three years.

[Stalebread]

New information from the Kepler planet-hunting satellite

LINK

[ZAZ]

Interesting article. Thanks for sharing.