Posted on by Nancy Atkinson

Powerhouse Black Hole Blows a Huge Bubble

Combining observations done with ESO's Very Large Telescope and NASA's Chandra X-ray telescope, astronomers have uncovered the most powerful pair of jets ever seen from a stellar black hole. The black hole blows a huge bubble of hot gas, 1,000 light-years across or twice as large and tens of times more powerful than the other such microquasars. The stellar black hole belongs to a binary system as pictured in this artist's impression. Credit: ESO/L. Calçada
Artist's impression of a Star feeding a black hole. Credit: ESO/L. Calçada

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A relatively small black hole is producing tremendously powerful jets while creating a huge bubble of hot gas. Both the jets and the bubble are the largest ever seen, meaning this mini black hole is a powerhouse. But the most unusual feature of this remarkable black hole is not its energy output, but how it is emitting energy.

“The energy output is impressive, but is comparable with the X-ray luminosity of so-called Ultraluminous X-ray sources,” said Manfred Pakull, the lead author of a new paper published today in Nature. “The notion that powerhouses exist that generate most of their energy in the form of jets (kinetic energy) and not as radiation (photons) is rather new.”

Black holes are known to release an incredible amount of energy when they swallow matter, and as Pakull told Universe Today, it was previously thought that most of the energy came out in the form of radiation, predominantly X-rays. But this new gas-blowing black hole, called S26, is showing that some black holes can release at least as much energy, and perhaps much more, in the form of collimated jets of fast moving particles.

“This black hole is just a few solar masses, but is a real miniature version of the most powerful quasars and radio galaxies,” said Pakull, “which contain black holes with masses of a few million times that of the Sun.”

This object is a microquasar, which are formed by two objects — either a white dwarf, neutron star or a black hole, along with a companion star. The X-rays are produced by matter falling from one component to the other, and can produce jets of high-speed particles. The fast jets slam into the surrounding interstellar gas, heating it and triggering an expanding bubble made of hot gas and ultra-fast particles colliding at different temperatures.

Of the dozen or so microquasars that have been found in the Milky Way Galaxy, most of the bubbles are fairly small, – less than 10 light-years across. But this one is 1,000 light-years wide. Plus this microquasar is tens of times more powerful than ones previously seen.

Using ESO’s Very Large Telescope and NASA’s Chandra X-ray telescope Pakull and his team were able to observe the areas where the jets smash into the interstellar gas around the black hole, and saw that the bubble of hot gas is inflating at a speed of almost one million kilometers per hour.

The jets are equally impressive, about 300 parsecs long, and although powerful jets have been seen from supermassive black holes, they were thought to be less frequent in the smaller microquasar variety. This new discovery may have astronomers looking more closely at other microquasars.

“The length of the jets in NGC 7793 is amazing, compared to the size of the black hole from which they are launched,” said co-author Robert Soria. “If the black hole were shrunk to the size of a soccer ball, each jet would extend from the Earth to beyond the orbit of Pluto.”

S26 is located 12 million light-years away, in the outskirts of the spiral galaxy NGC 7793. From the size and expansion velocity of the bubble the astronomers have found that the jet activity must have been ongoing for at least 200,000 years.

With all this incredible speed, size and activity, what do Pakull and his team project as the future of this microquasar?

“Yes, the expansion velocity (275 km/s) is quite impressive, but it will diminish with time,” Pakull told Universe Today. “If it was much lower at, say, 70 km/s the shocked gas would not emit so much optical light (for example the Balmer series of Hydrogen) and we would not have detected the bubble. The future of S26 depends on the evolution of the central microquasar which emits the jets. I expect that it could be active for another 100,000 to few million years.”

Pakull said it is interesting to imagine what would happen if the microqusar suddenly stopped emitting the jets. “Then the bubble would not suddenly disappear, but shine on like before for another few 100,000 years,” he said. “It would resemble a supernova remnant, albeit with a 100 times higher energy content.”

Pakull added that this new finding will help astronomers understand the similarity between small black holes formed from exploded stars and the supermassive black holes at the centers of galaxies, and he hopes this work will stimulate more theoretical work in how black holes produce energy.

Read the team’s paper (pdf file)

Sources: ESO, email exchange with Manfred Pakull.

Posted on by Nancy Atkinson

Curiosity Gets Her Wheels

She’s a rover with places to go and things to do, so one of the main components of NASA’s next Mars rover, the Mars Science Lab (named Curiosity) is wheels. Last week, the wheels and a suspension system were installed on the rover, an important step in getting ready for her mission to Mars. Launch is currently scheduled for sometime between November 25 and Decemeber 18, 2011, and Curiosity’s mission is to study its landing site for habitable environments – both ancient and current.
Continue reading “Curiosity Gets Her Wheels”

Posted on by Nancy Atkinson

Small Moon Makes Big Waves

A Cassini image of the moon Daphnis making waves in Saturn's rings. Credit: NASA/JPL/Space Science Institute

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Saturn’s moon Daphnis is only 8 kilometers wide, but it has a fairly substantial effect on the A ring, making waves on the ring’s edge. According to Carolyn Porco on Twitter, this is the closest look yet at this mini, moving moon. Daphnis resides in the Keeler Gap, which is about 42 km wide, but the moon’s eccentric orbit causes its distance from Saturn to vary by almost 9 km, and its inclination causes it to move up and down by about 17 km. That may not sound like much, but within a small gap, this variability causes the waves seen in the edges of the gap. We’ve only known about Daphnis’ existence since 2005, one of the many discoveries made by the Cassini spacecraft, and this is the first image where Daphnis is more than just a little dot. Click on the image to get a closer look.

This image is hot off the presses, as it was taken on July 5, 2010, and sent to Earth just yesterday (July 6). See below for a great new look at Saturn’s ring.


New raw image of Saturn's rings. Credit: NASA/JPL/Space Science Institute

Click the image for a larger version, and prepare to be wowed!

Source: CICLOPS, with a hat tip to Stu Atkinson!

Posted on by Nancy Atkinson

SETI Chile Interview

Working on the internet provides the opportunity to meet people from all around the world, and I’ve gotten acquainted with Lourdes Cahuich, an astronomy and science enthusiast and translator from Mexico and Tiare Rivera from Chile, who is the editor of the SETI Chile website. They regularly translate Universe Today articles (and articles and podcasts from many other English-language sites) and post them on their website in Spanish, making space and astronomy news more accessible to more of the world. They both are working on a series of interviews with people involved in space and astronomy outreach, and I am honored that Lourdes wanted to interview me! You can read the interview here in English, or if you prefer, here en Español. I reveal all about how and why I started writing, and how I ended up at Universe Today.

Above is the English version of SETI.CL’s promo video.

Posted on by Nancy Atkinson

Hayabusa Sample Return Canister Opened, Contains Material

Hayabusa's sample return canister was opened to reveal a small particle inside. Credit: JAXA

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The sample return canister from the Hayabusa spacecraft has been opened, and does contain a small amount of dust particles, according to the JAXA website. This is very encouraging news! However, it is not yet known if the dust is from the asteroid Itokawa, where Hayabusa briefly touched down, or if it could be from Earth — left in the container from before launch, or it possibly could have made its way in there during the landing/post landing handling. “Material on the planet or asteroid or particulate matter is at this stage is unknown, we will consider in detail,” is the Google translate version of the JAXA press release. According to Emily Lakdawalla at the Planetary Society, the dust grains are extremely small, about 0.01-millimeter in size, and there are about a dozen of them inside the container. This image was taken on June 28, 2010, and below is a magnified view of one of the particles.

Magnified view of a dust particle in the Hayabusa canister. Credit: JAXA

This magnified view was taken on June 29, and shows a magnified view of one very small particle being picked up by a quartz manipulator, which appears as a stripe on the image.
It likely will take several weeks to confirm whether the particles are from the asteroid, but if so, would be the first-ever asteroid sample return.

Below is an image of Earth that Hayabusa took as it approached the home planet.

Earth seen by the returning Hayabusa. Credit: JAXA

Sources: JAXA, The Planetary Society, BBC

Posted on by Nancy Atkinson

All-Sky Stunner from Planck

A multi-color all-sky image of the microwave sky. Credit: ESA, HFI and LFI consortia

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After a year of observations, the Planck observatory team released an all-sky microwave image, and what a gorgeous image it is! The Planck satellite looks at the entire sky in the microwave region of the electromagnetic spectrum, (30 to 857 GHz) with the main goal of tracking down the echoes of the Big Bang, the Cosmic Microwave Background (CMB.) This new image reveals the cosmic signal is literally hidden behind a fog of foreground emission, arising mostly from the interstellar medium (ISM), the diffuse mixture of gas and dust filling our Galaxy.

At the top and bottom of the image in the red and yellow marbled region is where the CMB is visible.

“By contrast, a good part of the sky is dominated by the Milky Way contribution, shining strongly along the Galactic Plane but also extending well above and below it, albeit at a very much lower intensity,” said Jan Tauber, Planck Project Scientist.

To produce this image, the Planck team combined data from the full frequency range of Planck. The main disc of our Galaxy runs across the center of the image, with streamers of cold dust reaching above and below the Milky Way. This galactic web is where new stars are being formed, and Planck has found many locations where individual stars are edging toward birth or just beginning their cycle of development.

To get your bearings of where everything is locatated, here is an annotated version.

Annotated version of the Planck all-sky image. Credit: ESA, HFI and LFI consortia.

“Planck has ‘painted’ us its first spectacular picture of the Universe,” said Dr. David Parker, Director of Space Science and Exploration for the UKSpace Agency. “This single image captures both our own cosmic backyard — the Milky Way galaxy that we live in — but also the subtle imprint of the Big Bang from which the whole Universe emerged. We’re proud to be supporting this great new discovery machine and look forward to our scientists unraveling the deeper meaning behind the beauty of this first image.”

And this is just the beginning of beautiful things from Planck!

Here’s another annotated version:

Planck all-sky annotated image. Credit: ESA, HFI and LFI consortia.

(Thanks to IVAN3MAN for suggesting to add this image.)

For more info see this ESA webpage, and the Planck website.

Posted on by Nancy Atkinson

New Satellite for Monitoring Space Debris To Launch

The Air Force Space Based Space Surveillance (SBSS) system. Credit: Boeing

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The U.S. Air Force will launch the first-ever satellite dedicated solely to tracking the positions of other satellites and the thousands of pieces of space debris in Earth orbit. The $500 million Space-Based Space Surveillance satellite, scheduled for a July 8 launch from Vandenberg Air Force Base, in California, will continuously monitor the “traffic” around the Earth, providing an unobstructed view day or night. Currently, the ground-based radar and optical telescopes used to track satellites and space junk can only be used on clear nights, and not all the observatories are powerful enough to detect objects in high or geosynchronous orbits.

This is the first satellite in the SBSS System that will eventually lead to a constellation of satellites to detect and track orbiting space objects, according to Boeing, the prime contractor for this first “Pathfinder” satellite. While the Air Force is the primary user of the SBSS satellites, the US Department of Defense will also use data from the eventual satellite system to support military operations, and NASA can use the information to calculate orbital debris collision-avoidance measures for the International Space Station and Space Shuttle missions.

The Air Force estimates there are about 1,000 functioning satellites and about 20,000 pieces of debris orbiting Earth.

The new satellite will be in orbit 627 kilometers (390 miles) above the Earth, and has an optical camera on a swivel mount, so the camera’s view can be changed without burning fuel to move the satellite, and will concentrate on satellites and debris in deep space. The information from the satellite will be sent to a command center at Schriever Air Force Base in Colorado.

The Air Force space surveillance network previously had partial use of a satellite called the Midcourse Space Experiment, which was designed to track missiles but could also monitor objects in orbit. It’s no longer functioning.

Right now, the Air Force can detect objects as small as 10 centimeters across, or about 4 inches, and they have not released information on the the capabilities of the new satellite.

The Secure World Foundation says there could be millions of pieces of debris in total around the Earth. Debris at altitudes above several hundred kilometers can stay in orbit for decades or even centuries, and those about 1,500 kilometers will remain in orbit for thousands of years. Even very small particles of space debris can have a devastating effect on anything they hit because of their high relative impact velocities.

Chart of orbital debris. Source: NASA Orbital Debris Quarterly News, April 2009,

This chart displays a summary of all objects in Earth orbit officially cataloged by the U.S. Space Surveillance Network. “Fragmentation Debris” includes satellite breakup debris and anomalous event debris, while “Mission?related Debris” includes all objects dispensed, separated, or released as part of the planned mission. Note the dramatic increase in fragmentation debris caused by the Chinese ASAT test conducted in January 2007. Another smaller increase is noted following the 2009 collision between an Iridum communications satellite and a non-functioning Russian satellite.

It is hoped the new SBSS satellite will increase the capabilities to help avoid future collisions.

Sources: Boeing, Secure World Foundation, AP

Posted on by Steve Nerlich

Astronomy Without A Telescope – Animal Astronomy

Avian astronomers at work. Credit: abc.net.au.

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In the 1950s, the Sauer research team locked some birds in Olbers planetarium and started messing with them. First they projected a northern hemisphere autumn sky and the birds flew ‘south’ – away from Polaris and keeping Betelgeuse to the left (‘east’). Then they projected a spring night sky and the birds flew ‘north’ towards Polaris with Betelgeuse again to their left, albeit this time in the ‘west’. The position of Betelgeuse appeared to be significant, perhaps because it’s one of the brighter stars in the northern hemisphere and just to the north of the celestial equator.

Later experiments with Indigo Buntings demonstrated that birds raised with no experience of the night sky didn’t have a clue what to do when released into a planetarium. However, birds that were raised with the night sky visible would fly ‘south’ away from the sky’s axis of rotation, whether that was Polaris or an artificial arbitrary axis created within the planetarium.

From this work, researchers concluded that it was unlikely that birds were born with a genetic star map, but instead learned to orientate themselves with respect to the rotating night sky by reference to other directional cues – like the position of the Sun and the Earth’s magnetic field.

It’s thought that many migratory birds closely monitor sunrise and sunset – allegedly when you see a line of birds on a power line, most will be facing east in the morning and west in the evening, recalibrating their internal compasses. Checking for a north-south plane of polarized light at sunrise and sunset may help them determine their latitude – by indicating how far off due east or west the Sun is when it’s at the horizon.

Pigeons have well developed magnetoreception that they can use as an alternative to solar navigation. For example, they can ‘home’ even with a heavily overcast sky – but get them to wear a little magnetized helmet that screws up their perception of the Earth’s magnetic field and they get lost. On the other hand, if it’s a clear day with the Sun visible they can find home just fine – even with a little magnetized helmet on.

As well as the birds – bacteria, bees, termites, lobsters, salamanders, salmon, turtles, mole rats and bats have all been shown to possess magnetoreception.

Magnetotactic bacteria manufacture their own magnetite crystals – building chains of crystals that mimic a compass needle. The bacteria appear to use their magnetite crystals for the simple purpose of determining which way is down – since a straight line to magnetic north will pass through the Earth’s surface.

Magnetospirillum with a line of synthesized magnetite crystals visible. Credit: www.microbiologybytes.com

It’s yet to be determined how a complex nervous system might interface with magnetite or whether magnetite is the primary mechanism in larger multicellular animals. Magnetite crystals have been isolated from bees and termites – and are apparently synthesized by them. However, in larger animals it’s harder to tell – as these crystals are tiny and difficult to find or visualize in vivo. An alternate magnetoreception mechanism based on photochemicals in the retina has been proposed for migratory birds – although a role for magnetite, particularly in pigeons which have relatively large concentrations of it in their beaks, can’t be ruled out.

Humans have traces of magnetite in their brains – although the court is still out on whether this gives us any capacity for direction finding by magnetoreception. Some research suggests a few individuals may have some very minor ability – but not enough for anyone to consider preferring this to their GPS.