New Look at an Ancient Swarm of Stars

The globular cluster Messier 107, also known as NGC 6171. Credit: ESO

[/caption]

Globular clusters form during the earliest stages in a galaxy’s development, so clusters like this one, M 107, or NGC 6171 are some of the oldest objects in the Universe. Typically, globular clusters formed about 10 billion years ago, and astronomers say that studying these objects can provide significant insights into how galaxies, and their component stars evolve. While M 107 has been observed many times, this new look from ESO shows a stunning view of this swarm of stars.

Located about 21,000 light years away, M107 is not visible to the naked eye. But, with an apparent magnitude of about eight, it can easily be observed from a dark site with binoculars or a small telescope.

The globular cluster is about 13 arcminutes across and is found in the constellation of Ophiuchus, north of the pincers of Scorpius. Roughly half of the Milky Way’s known globular clusters are actually found in the constellations of Sagittarius, Scorpius and Ophiuchus, in the general direction of the centre of the Milky Way. This is because they are all in elongated orbits around the central region and are on average most likely to be seen in this direction.

This image is composed from exposures taken through the blue, green and near-infrared filters by the Wide Field Camera (WFI) on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile.

Source: ESO

Akatsuki Fails to Enter Orbit of Venus

Artist’s impression of the Venus Climate Orbiter (aka. “Akatsuki”) by Akihiro Ikeshita. Image Credit: JAXA

JAXA announced that the Akatsuki spacecraft failed to enter orbit around Venus. The orbit insertion maneuver was performed, the space agency said in a statement, but “unfortunately, we have found that the orbiter was not injected into the planned orbit as a result of orbit estimation.” While extremely disappointing, perhaps not all is lost. If the spacecraft can be stabilized, there is a chance it could enter orbit in 6 years when it passes by Venus again.

At a press conference, project manager Masato Nakamura said (from translated reports) that the spacecraft is functioning but has put itself in a standby mode with its solar panels facing towards the Sun. It is also spinning slowly — about every 10 minutes — and radio contact is possible only for 40 seconds at a time. Engineers are using ground antennas in Japan as well as NASA’s Deep Space Network to send commands to stabilize the spacecraft and to determine its trajectory.

JAXA said they have set up an investigation team to study the cause of the failure, and will provide updates with the countermeasures and investigation results.

Japan had a similar situation occur with their Nozomi spacecraft at Mars in 2003, when they lost contact with the spacecraft just 5 days before orbit insertion around the Red Planet.

Akatsuki was launched from the Tanegashima Space Center on May 21, 2010.

Deepest Hole In The World

Deepest Hole In The World
Deepest Hole In The World. Image Source: chattablogs.com

[/caption]

The deepest hole in the world is on the Kola peninsula of Russia near the Norwegian border. This hole is being drilled for scientific study purposes and is currently over 12,200 meters deep.

In 1926, Harold Jeffreys hypothesized that a transition zone within the crust, identifiable on seismic records as a “jump” in seismic velocity, could be attributed to a change in rock type from granite to a denser basalt. The deepest hole in the world being drilled at the Kola well has now penetrated about halfway through the crust of the Baltic continental shield, exposing rocks 2.7 billion years old at the bottom. One of the more fascinating scientific findings to emerge from this well is that the change in seismic velocities was not found at a boundary marking(Jeffreys’ hypothetical transition from granite to basalt), but it was at the bottom of a layer of metamorphic rock that extended from about 3.5 to about 9.8 km beneath the surface. This rock had been thoroughly fractured and was saturated with water. Free water should not be found at these depths. This could only mean that water which had originally been a part of the chemical composition of the rock minerals themselves had been forced out and prevented from rising by a cap of impermeable rock.

This discovery has an impact on geophysical sciences and there is a potential economic impact. This water is very highly mineralized, and is a primary concentrating agent for most ore deposits. The technology for mining at these depths is not yet available. In order to get their single drill hole down as far as they did, the Soviets had to resort to experimental methods. Their chief innovation was that, instead of turning the drill bit by rotating the stem, in the Kola well the bit alone was turned by the flow of drilling mud.

As drilling continues at the deepest hole in the world many scientists are hoping for additional discoveries and a greater understanding of the inner workings and makeup of our planet.

We have written many articles about the deepest hole in the world for Universe Today. Here’s an article about how far the center of the Earth is, and here’s a forum discussion about the drillings through the Earth’s crust.

If you’d like more info on the Earth’s deepest hole, check out the 10 amazing holes in the Earth. And here’s a link to NASA’s Earth Observatory.

We’ve also recorded an episode of Astronomy Cast all about planet Earth. Listen here, Episode 51: Earth.

Source: Wikipedia

Large Binocular Telescope Achieves First Light

Large Binocular Telescope
Left: The Large Binocular Telescope at Mt. Graham, Arizona. Right: First light image taken by the Large Binocular Telescope Interferometer, which can search for dust and large exoplanets around nearby stars.

After eight and a half years in the making, the Large Binocular Telescope (LBT) is finally ready to begin operation. Yesterday, it unveiled its first image (shown above), the target of which was Beta Pictoris.

Continue reading “Large Binocular Telescope Achieves First Light”

Stars Shrouded in Glittering Zirconium Light up the Sky

Artist’s impression of LS IV – 14 116. The white clouds are rich in zirconium and lie above the blue surface of the star. Image: Natalie Behara

[/caption]

Its been said that the Universe isn’t stranger than you can imagine, its stranger than you can’t imagine. Nowhere is this more true than the study of stars. Recently, a team of scientists from the Armagh Observatory in Northern Ireland have discovered a star that is enveloped by clouds of glittering zirconium! Its a metal you might be more familiar with in jewelry to make false diamonds but it now looks like stars are getting in on the act and becoming more sparkly than they are already.

The research team, led by graduate student N. Naslim and her supervisor Dr. Simon Jeffrey, were looking for clues to the lack of hydrogen on the surface of helium rich hot subdwarf stars, when compared to other similar stars. Using the 3.9m Anglo-Australian telescope at Siding Spring Observatory in New South Wales, the study focused on a star called LS IV-14 116 which lies at an incredible distance of 2000 light years.

By using a spectroscope attached to the telescope, the team was able to split the incoming starlight into its component parts (much like water droplets in the atmosphere do to sunlight to make a rainbow). Along with the expected patterns which showed the presence of certain elements, they were surprised to find lines in the spectrum which were not so easily identified. A careful study showed the lines were due to the presence of a form of zirconium that should only exist in temperatures in excess of 20,000 degrees. This was a first, no zirconium of this type had ever been found in a stellar spectrum before.

Team member Prof. Alan Hibbert built a computer model that enabled them to deduce that the zirconium existing on LS IV-14 116 was some ten thousand times more than the concentration found in the Sun. This highly unexpected result led the team to conclude that the abundance of zirconium is caused by the formation of cloud layers in the star’s atmosphere.

“The star doesn’t have a corona like the Sun. Our model shows the huge excess of zirconium that we discovered is on the photosphere (the visible ‘surface’ of the star), where it forms cloud layers much like stratus clouds on Earth.” Naslim told Universe Today. It seems that other elements, chiefly metals heavier than calcium, seem to form in high concentrations too but seem scarce in layers above and below. This could have a dramatic effect according to Dr. Natalie Behara from the Université Libre de Bruxelles appearing as many thin cloud layers in the atmosphere, each due to a different metal.

Further work from the team suggests that the star is shrinking from a bright cool giant to a faint hot subdwarf and as it does, different elements sink or float up in the atmosphere making the current composition very specific to the star’s recent history.

Naslim explains that “The huge excess of zirconium was a complete surprise. We had no reason to think this star was more peculiar than any other faint blue star discovered so far.” Its great to see that whilst we know so much about the Universe now, there are still discoveries that come along and surprise us. This latest discovery of zirconium rich stars has yet again shown us that we mustn’t become complacent and think we know everything, it keeps science interesting, it keeps it alive.

Source: from the Royal Astronomical Society.

Mark Thompson is a writer and the astronomy presenter on the BBC One Show. See his website, The People’s Astronomer, and you can follow him on Twitter, @PeoplesAstro

SpaceX Shoots for Dec. 8 Launch of Falcon 9

SpaceX has decided to try and launch its Falcon 9 rocket on Wednesday, Dec. 8. Photo Credit: Jason Rhian

[/caption]

CAPE CANAVERAL –Engineers with the commercial space company SpaceX have analyzed two small cracks in the rear segment of the second stage engine nozzle. These cracks are located near the end of the nozzle extension where there is very little stress and so it is thought that they in themselves would not cause a flight failure. SpaceX decided that they did warrant further investigation to make sure that these cracks are not symptoms of a far larger problem.

SpaceX must have liked what they saw because the company has decided to go ahead with the launch, now scheduled for Wednesday. The launch window will open at 9 a.m. EDT and will close at 12:22 p.m. EDT.

The bell shaped Merlin Vacuum nozzle is made out of niobium sheet alloy, and is approximately 9 feet tall and 8 feet at the base. This nozzle thins out to approximately twice the thickness of a soda can near the end. Although it is composed of a refractory alloy metal and has a melting temperature high enough to boil steel, this component is, in geometric terms, the simplest component of the engine.

The niobium nozzle extension works to increase the overall efficiency of the Merlin engine while on-orbit. For this first flight of the Dragon, this efficiency is not required, but the component was placed on the rocket’s second stage by default.

SpaceX is launching the first of its Dragon spacecraft on the first demonstration flight under the $1.6 billion Commercial Orbital Transportation Services (COTS) contract that the space firm has with NASA. Under this contract SpaceX is required to fly three demonstration flights before conducting 12 supply missions to the International Space Station (ISS).

SpaceX is pushing ahead with the launch of its Falcon 9 rocket containing the Dragon spacecraft. Photo Credit: Jason Rhian

How To Dispose of a Space Station

Space Station
The International Space Station in 2010. Credit: NASA

[/caption]

With the life of the International Space Station extended to at least 2020, we don’t have to think about its demise for awhile. But actually, NASA and the international partners do have to think about and plan ahead for how this huge 400-ton structure in space will one day be deorbited and disposed of. Friend and venerable space writer Leonard David has written an article about how NASA is starting to consider how they will organize and execute “dumping the huge facility into select, but remote, ocean waters in one fell swoop.” It ain’t gonna be easy, and that’s why thorough planning is a must. It might take a combination of vehicles (ESA’s ATV, Russian Progess) to send the ISS on a very safe and precise swan dive. Or, another possibility is that some of the modules could be re-used elsewhere.

Check out the article on Space.com

Sneak Attacks from the Sun

This image combines all of STEREO's wavelengths into one three-dimensional photograph (visible with 3D anaglyph glasses). Credit: NASA

[/caption]

From a Harvard Smithsonian Center for Astrophysics press release:

Our Sun can be a menace when it sends out powerful solar blasts of radiation towards the Earth. Astronomers keenly watch the Sun to learn more about what powers these solar eruptions, in hopes of being able to predict them. New research shows that one-third of the Sun’s blasts are “sneak attacks” that may occur without warning.

“If space weather forecasters rely on some of the traditional danger signs, they’ll miss a significant fraction of solar eruptions,” said Suli Ma of the Harvard-Smithsonian Center for Astrophysics (CfA).

To reach their conclusion, Ma and her colleagues studied 34 solar eruptions over 8 months using the STEREO spacecraft. STEREO allows us to study the Sun from two different angles simultaneously. It consists of two spacecraft, one ahead of Earth in its orbit and the other trailing behind. The researchers used it to ensure that the events leaving the Sun were definitely on the side facing the Earth.

STEREO is ideal for studying coronal mass ejections, or CMEs. A CME is a huge eruption from the Sun that blasts a billion tons of highly charged particles into space at speeds greater than a million miles per hour. When those charged particles reach Earth, they interact with our planet’s magnetic field, potentially creating a geomagnetic storm. Such a storm can interfere with satellite communications, disrupt power grids, or even short out orbiting satellites.

Previous to STEREO, astronomers thought that all Earth-facing CMEs were accompanied by warning signals like flares (smaller explosions accompanied by high-energy radiation), coronal dimmings (darkening of the corona caused by discharge of matter in the CME) or filament eruptions (long ribbons of plasma arching violently out from the solar surface). Therefore, by watching for those signals, we could potentially predict an impending eruption.

This new research found that 11 of the 34 CMEs observed by STEREO were “stealthy,” showing none of the usual signals. As a result, any system designed to watch for such warning signs could miss one-third of all solar blasts.

“Meteorologists can give days of warning for a hurricane, but only minutes for a tornado,” explained Smithsonian astronomer Leon Golub. “Currently, space weather forecasting is more like tornado warnings. We might know an eruption is imminent, but we can’t say exactly when it will happen. And sometimes, they catch us by surprise.”

The team plans to continue looking for subtle clues that might allow us to predict an impending “stealth” CME. They caution that their study occurred during a prolonged minimum of solar activity; conditions may change as solar activity increases over the next few years.

“The Sun is entering its stormy season, ramping up toward its next period of maximum activity in 2013 and 2014,” said Ma. “The more we learn and understand about it now, the better.”

The paper discussing their findings appeared in the Oct. 10, 2010 issue of The Astrophysical Journal. It was authored by Suli Ma, G. Attrill, and Leon Golub (CfA); and J. Lin (Chinese Academy of Sciences).

The Zooniverse is Expanding: The Milky Way Project Begins Today

The Milky Way Project allows anyone to help catalog bubbles and other interesting features in images taken from a robotic infrared survey. Image Credit: Spitzer/The Milky Way Project

[/caption]

From the folks that brought you the addictive citizen science projects Galaxy Zoo and Moon Zoo (among others), comes yet another way to explore our Universe and help out scientists at the same time. The Milky Way Project invites members of the public to look at images from infrared surveys of our Milky Way and flag features such as gas bubbles, knots of gas and dust and star clusters.

As with the other Zooniverse projects, the participation of the public is a core feature. Accompanying the Milky Way Project is a way for Zooniverse members – lovingly called “zooites” – to discuss the images they’ve cataloged. Called Milky Way Talk, users can submit images they find curious or just plain beautiful to the talk forum for discussion.

The Milky Way Project uses data from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) and the Multiband Imaging Photometer for Spitzer Galactic Plane Survey (MIPSGAL). These two surveys have imaged the Milky Way in infrared light at different frequencies. GLIMPSE at 3.6, 4.5, 5.8, and 8 microns, and MIPSGAL at 24 and 70 microns. In the infrared, things that don’t emit much visible light – such as large gas clouds excited by stellar radiation – are apparent in images.

The new project aims at cataloging bubbles, star clusters, knots of gas and dark nebulae. All of these objects are interesting in their own ways.

Bubbles – large structures of gas in the galactic plane – belie areas where young stars are altering the interstellar medium that surrounds them. They heat up the dust and/or ionize the gas that surrounds them, and the flow of particles from the star pushes the diffuse material surrounding out into bubble shapes.

The green knots are where the gas and dust are more dense, and might be regions that contain stellar nurseries. Similarly, dark nebulae – nebulae that appear darker than the surrounding gas – are of interest to astronomers because they may also point to stellar formation of high-mass stars.

Star clusters and galaxies outside of the Milky Way may also be visible in some of the images. Though the cataloging of these objects isn’t the main focus of the project, zooites can flag them in the images for later discussion. Just like in the other Zooniverse projects, which use data from robotic surveys, there is always the chance that you will be the first person ever to look at something in one of the images. You could even be like Galaxy Zoo member Hanny and discover something that astronomers will spend telescope time looking at!

This image is full of objects that are interesting to astronomers for study. You can help them pick out which things to study. Image Credit: Spitzer/The Milky Way Project

The GLIMPSE-MIPSGAL surveys were performed by the Spitzer Space Telescope. Over 440,000 images – all taken in the infrared – are in the catalog and need to be sifted through. This is a serious undertaking, one that cannot be accomplished by graduate students in astronomy alone.

In cataloging these bubbles for subsequent analysis, Milky Way Project members can help astronomers understand both the interstellar medium and the stars themselves imaged by the survey. It will also help them to make a map of the Milky Way’s stellar formation regions.

As with the other Zooniverse projects, this newest addition relies on the human brain’s ability to pick out patterns. Diffuse or oddly-shaped bubbles – such as those that appear “popped” or are elliptical – are difficult for a computer to analyze. So, it’s up to willing members of the public to help out the astronomy community. The Zooniverse community boasts over 350,000 members participating in their various projects.

A little cataloging and research of these gas bubbles has already been done by researchers. The Milky Way Project site references work by Churchwell, et. al, who cataloged over 600 of the bubbles and discovered that 75% of the bubbles they looked at were created by type B4-B9 stars, while 0-B3 stars make up the remainder (for more on what these stellar types mean, click here).

A zoomable map that uses images from the surveys – and has labeled a lot of the bubbles that have been already cataloged by the researchers- is available at Alien Earths.

For an extensive treatment of just how important these bubbles are to understanding stars and their formation, the paper “IR Dust Bubbles: Probing the Detailed Structure and Young Massive Stellar Populations of Galactic HII Regions” by Watson, et. al is available here.

If you want to get cracking on drawing bubbles and cataloging interesting features of our Milky Way, take the tutorial and sign up today.

Sources: The Milky Way Project, Arxiv, GLIMPSE

How Many Astronauts Does NASA Need?

The White House is looking into ways to reduce the number of astronauts employed by the U.S. Image Credit: NASA

[/caption]

CAPE CANAVERAL – When we think of NASA, the first thing that most Americans picture is the men and women of the astronaut corps. It turns out that the White House has been thinking about them as well – as maybe something that might need to be cut down. The Obama administration has requested a 10-month long study be held to determine the appropriate ‘size’ of NASA’s astronaut corps.

There are only two (and a potential third) shuttle flights remaining on the current manifest.

Right now, NASA has 64 astronauts, which some might consider a bit much if very few will be flying to space. However, if three NASA astronauts are part of each 6-member, 6-month Expedition on the International Space Station from 2011-2017 (the projected time period when NASA will be unable to launch their own astronauts) that still is 36 astronauts with a mission to space.

But the proposal to cut NASA’s astronaut corps comes on the heels of numerous successive cuts that the space agency has endured over the past year. Many view the loss of the corps as one more blow to both spaceflight experience as well as national prestige.

The White House hopes that commercial space companies such as SpaceX, which is slated to launch the second of its Falcon 9 rockets sometime this week, will emerge to fill the void created by NASA’s absence. However, to date, none of these firms have launched an astronaut into orbit. During the interim, and until NASA can build its own heavy lift vehicle, the US space agency is relying on — and paying — the Russians to bring US astronauts to the ISS via the Soyuz.

There has never been more than 150 astronauts at any given time (the most ever was 149 back in 2000). Although most Americans assume that NASA has a massive budget, for what the agency does and provides, it is incredibly small, about one-seventh of a penny out of every tax dollar helps to pay for the ISS, the shuttle program, the probes and rovers to the planets and the astronaut’s salaries. The agency’s budget is currently $18.7 billion a year. The 47 civilian astronauts earn between $65,000 and $100,000 annually, with the remaining military astronauts being paid through the Department of Defense (DoD) which NASA reimburses.

The National Academies is the organization that will conduct the review of the astronaut corps and they are leaving no stone unturned, even the T-38 ‘Talon’ jets that the astronauts fly in, are coming under scrutiny. These jets are not state-of-the-art fighters, but rather training aircraft that date back to the beginning of the space age. These planes, equipment and facilities used to train astronauts and the current number of astronauts will all be reviewed.

“I still don’t know how many folks are in the queue and were not selected for shuttle, ” said two-time shuttle astronaut Robert Springer. “If you are in the program and there is little or no chance to fly in the next 4-8 years that’s too bad, but it’s not the first time this has happened, and if you like the environment, working with some of the greatest people in the business, it can lead to challenging working on the next great enterprise.”

But some have a different idea of how NASA could cut costs.

“You know, if Obama really wanted to cut waste at NASA – he’d start with headquarters,” said a long-time NASA employee who requested to remain anonymous for fear of retribution. “That place is stocked with GS-15s – who really don’t do much of anything!” He said referring to the government pay grade of many of the high-level officials that work at NASA’s headquarters in Washington D.C.