Warm dust resolved in the cold disk around T?Chamaeleontis with VLTI/AMBER?

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Authors: J. Olofsson, M. Benisty, J.-C. Augereau, C. Pinte, F. Ménard, E. Tatulli, J.-P. Berger, F. Malbet, B. Merín, E. F. van Dishoeck, S. Lacour, K. M. Pontoppidan, J.-L. Monin, J. M. Brown and G. A. Blake.<br />Astronomy & Astrophysics Vol. 528 , page L6<br />Published online: 24/02/2011<br />
Keywords:
stars: pre-main sequence ; stars: evolution ; protoplanetary disks ; circumstellar matter ; infrared: stars ; techniques: interferometric.

Global e-VLBI observations of the gamma-ray narrow line Seyfert 1 PMN J0948+0022

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Authors: M. Giroletti, Z. Paragi, H. Bignall, A. Doi, L. Foschini, K. É. Gabányi, C. Reynolds, J. Blanchard, R. M. Campbell, F. Colomer, X. Hong, M. Kadler, M. Kino, H. J. van Langevelde, H. Nagai, C. Phillips, M. Sekido, A. Szomoru and A. K. Tzioumis.<br />Astronomy & Astrophysics Vol. 528 , page L11<br />Published online: 02/03/2011<br />
Keywords:
galaxies: active ; galaxies: Seyfert ; galaxies: jets ; instrumentation: high angular resolution ; instrumentation: interferometers.

Concurrent X-ray, near-infrared, sub-millimeter, and GeV gamma-ray observations of Sagittarius A*

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Authors: G. Trap, A. Goldwurm, K. Dodds-Eden, A. Weiss, R. Terrier, G. Ponti, S. Gillessen, R. Genzel, P. Ferrando, G. Bélanger, Y. Clénet, D. Rouan, P. Predehl, R. Capelli, F. Melia and F. Yusef-Zadeh.<br />Astronomy & Astrophysics Vol. 528 , page A140<br />Published online: 16/03/2011<br />
Keywords:
Galaxy: center ; black hole physics ; radiation mechanisms: non-thermal ; X-rays: general ; infrared: general ; submillimeter: general.

The Biggest Full Moon in Years!

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Ok so it's not full but it is one of mine LOL.

 

We have a full moon coming in a couple of days.  Be sure to have a look and when you do, you might think the moon seems larger than normal.  Guess what?  You’d be right!  It is going to be the biggest full moon in years and this isn’t some stupid hoax.

Once about every 18 years the moon reaches perigee about one hour away from being full and this is the year and the 19th is the date.  Perigee? Perigee is just a term indicating the moon is as close to Earth as it gets in the natural order of things.  Yes, it will actually make the tides a bit higher but no need to panic it’s not going to make THAT much difference.  I mean the moon is still 221,567 miles away (356,577 km).

Here’s a video from Science@NASA:

 

Click here to view the embedded video.

History at Mercury!

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MESSENGER makes history at Mercury! Image: NASA

 

NASA’s MESSENGER spacecraft successfully achieved orbit around Mercury at about 9pm EDT on Thursday (Mar 18).  It’s been a long journey to one of the nearest planets. Launched August 3, 2004 the trip has been 4.9 BILLION miles (7.9 BILLION km)!! Hey it was fuel efficient though, the trip made use of the gravity assists of flybys to save fuel.

No, it’s never been done before.  You’d think it would have been long ago until you think about the technical challenges, heck just the temperature alone is huge, Mercury can reach over 441o F (227oC) on the dayside (hotter in spots) and -279oF (-144oC) on the nightside.

Mercury is a fun planet to ponder on, the sun is about nine times brighter than it is here.  There is almost no tilt to the planet so the poles are dark and extremely cold.  There has been radar signatures of ice at the poles, not sure if that was ever confirmed but at -234 degrees F if it was there, it still is.

Mercury does rotate slowly, about once every 58.7 days, and it has a year of about 88 days.  Since the rotation is exactly two thirds of its orbital period (year) a day on Mercury is 176 days long.  It’s called a 3:2 Spin-Orbit Resonance.

You’d also think the closest planet to the sun would have the most dead center orbit of all, being closest to the gravity source we orbit around, but no Mercury has an orbital inclination of 7 degrees the most of any planet.  This is different than the planet’s tilt, You can think of orbital inclination as the travel above and below the Sun’s equator.  Likewise you’d think Mercury would be the most circular of all,  but no, the orbit gets as close as 0.31 AU and as far as 0.47, this is known as the eccentricity and yes since Pluto is no longer a planet, I think that means Mercury is the most eccentric.

The Caloris Basin a crater 833 miles in diameter (1340 km) made as most craters are: a huge impact. In fact on the opposite side of the planet you can see where the seismic waves converged.  Maybe that’s why the iron core of Mercury is 75 percent of its radius and 60 percent of its mass.

Oh you can make Google Earth into Google Mercury with a KML file available at the the MESSENGER website.

It will be exciting to see the results of the MESSENGER mission as it unfolds as the science is set to start on April 4, 2011.

A Celestial Spider

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If you look in the Southern sky, in the Large Megallanic Cloud you’ll notice a milky patch.  Grab a telescope and you’ll see a celestial spider take shape.  That’s the Tarantula Nebula.  Originally thought to be a star, in 1751 Nicolas Louis de Lacaille identified it as a nebula.  It is very complex and interesting, and well worth a close look.

NASA/JPL-CalTech/UCLA WISE image of the Tarantula

The Tarantula is extremely luminous.  We don’t get the full effect with it being about 49 kpc away (that’s bout 160,000 light years), but if it were as close to us as, say, the Orion Nebula (the one on Orion’s belt, you know it), the Tarantula would cast shadows.  It is hugely luminous, with an apparent magnitude of 8.  We’re talking here about one of the most active regions in the Local Group.  With an estimated total mass of 450,000 solar, this puppy is massive.

NASA/ESA Hubble R136

At the Tarantula’s heart lies the R136 star cluster.  This is a “super star cluster” containing at least 39 O3 type stars, several Wolf-Rayet stars, and a core of 12 very massive, luminous stars.  One of the twelve, R136a1, is a blue supergiant, and with a mass of 265 solar it is one of the largest stars identified to date.  Big?  R136a1 has a luminosity 8,700,000 times that of the Sun.

NASA/ESA/ESO Hubble The Exile

The Tarantula also contains (for now) an “exile star”.  That’s a sad, sad story about a star that’s getting shot out into space at a high rate of speed.

NASA/ESA/JPL Hubble Hodge 301 lower right

Looking for more?  Hodge 301 is also located within the Tarantula.  Since its birth, Hodge 301 has had at least 40 stars within go supernova.  This is a violent, older region of the Tarantula.

NASA/ESA Hubble time lapse of SN1987A

And speaking of supernovae, the Tarantula gave us SN1987A, not to mention the most recent 2011 supernova.

This is an active, beautiful, and fully fascinating object.  There’s a lot going on here, and it’s well worth a closer look.  HubbleSite has many more images if you’re interested, otherwise, enjoy these few I’ve posted.  It’s a beauty.

Mercury or Bust!

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Mercury. The yellow box shows the first area to be photographed from orbit by Messenger. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

The planet Mercury is getting its day in the sun so to speak., you will be hearing a lot about the planet in the next few weeks.

Firstly,  I always like to get a look at Mercury when I can and now is a good time because Mercury is approaching eastern elongation. All that means is Mercury is approaching the point where it is at a point in it’s orbit where it appears to be at it’s eastern most point in it’s orbit around the Sun.

Okay, that’s not all it means, the best part is it also means we can see Mercury just after sunset in the western sky. Huh? Mercury is at eastern elongation and is seen in our western sky? Yeah, the Sun’s east! Here is a bit better explanation and a date calculator for both eastern and western elongation of Mercury. After the sun goes down and it starts to get dim, Mercury will pop out visually along about the same path as the sun took.

Get out there and have a look!

The other big news about Mercury is the Messenger spacecraft is poised to enter an orbit around the planet on March 18th! Finally!! This has been a long time coming and I have to tell you my fingers are crossed everything goes as planned. The environment isn’t exactly hospitable should something go awry.

The image above shows the area to be first photographed from orbit by Messenger, the first images will be taken on March 29th at 07:40 UTC and over the following six hours over 350 images will be taken and that is just the beginning of the discoveries to come.

The Messenger press release:

After more than a dozen laps through the inner solar system and six planetary flybys, NASA’s MESSENGER spacecraft will move into orbit around Mercury on at around 9 p.m. EDT on March 17, 2011. The durable spacecraft — carrying seven science instruments and fortified against the blistering environs near the Sun — will be the first to orbit the innermost planet.

“From the outset of this mission, our goal has been to gather the first global observations of Mercury from orbit,” says MESSENGER Principal Investigator Sean Solomon, of the Carnegie Institution of Washington. “At the time of our launch more than six and a half years ago, that goal seemed but a distant dream. MESSENGER is now poised to turn that dream into reality.”

Just over 33 hours before the main Mercury orbit insertion maneuver, two antennas from NASA’s Deep Space Network — one main antenna and one backup — will begin to track the MESSENGER spacecraft continuously. At 6:30 p.m. EDT on March 17, the number of antennas tracking MESSENGER will increase to five — four of these will be arrayed together to enhance the signal from the spacecraft, and a fifth will be used for backup.

At about 8 p.m., the solar arrays, telecommunications, attitude control, and autonomy systems will be configured for the main thruster firing (known as a “burn”), and the spacecraft, operating on commands transmitted last week from Earth, will be turned to the correct orientation for MESSENGER’s Mercury orbit insertion maneuver.

To slow the spacecraft down sufficiently to be “captured” by Mercury, MESSENGER’s main thruster will fire for about 15 minutes beginning at 8:45 p.m. This burn will slow the spacecraft by 1,929 miles per hour (862 meters per second) and consume 31 percent of the propellant that the spacecraft carried at launch. Less than 9.5 percent of the usable propellant at the start of the mission will remain after completing the orbit insertion maneuver, but the spacecraft will still have plenty of propellant for orbit adjustments during its yearlong science campaign.

After the burn, the spacecraft will turn toward Earth and resume normal operations. Data will be collected by Deep Space Network antennas and transferred to the Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., to be analyzed. It is expected that by 10 p.m. EDT, mission operators will be able to confirm that MESSENGER has been successfully captured into orbit around Mercury.

The maneuver — which will be completed at a time that MESSENGER is more than 96 million miles from Earth — will place the probe into an orbit that brings it as close as 124 miles to Mercury’s surface. At 2:47 a.m. EDT on March 18, the spacecraft will begin its first full orbit around Mercury, and the probe will continue to orbit Mercury once every 12 hours for the duration of its primary mission.

“For the first two weeks of orbit, we’ll be focused on ensuring that the spacecraft systems are all working well in Mercury’s harsh thermal environment,” says APL’s Eric Finnegan, the MESSENGER Mission Systems Engineer. “Starting on March 23 the instruments will be turned on and checked out, and on April 4 the science phase of the mission will begin and the first orbital science data from Mercury will be returned.”

While in orbit, MESSENGER’s instruments will perform the first complete reconnaissance of the cratered planet’s geochemistry, geophysics, geological history, atmosphere, magnetosphere, and plasma environment.

“The marathon cruise phase of the MESSENGER mission is nearing the finish line,” says Solomon. “Like a seasoned runner, the MESSENGER team is positioned to break through the tape. We are extremely excited by the prospect that orbital operations will soon begin.”

Intelligence Squared

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This is very short notice but I think will be well worth listening to.

 

A Journey Into Outer Space with Brian Cox

  • Are we alone in the universe? How will we ever find out?
  • How did the universe begin?
  • Will we ever find the mysterious “God particle”? What would it mean if we did?
  • How soon will we all become space tourists?

Just some of the questions to be explored today by a gathering of the world’s leading scientists and hosted by Brian Cox, BBC presenter and Particle physicist.

Speakers include:
Brian Cox, Professor of Particle Physics at the University of Manchester

Richard Holmes, Biographer whose latest book, The Age of Wonder, chronicles the scientists of the Romantic age who laid the foundations of modern science

Colin Pillinger, Planetary scientist best known as leader of the Beagle 2 project, the attempt to land a British built spacecraft on Mars in 2003

Martin Rees, Astronomer Royal

Charles Simonyi. Software architect and spaceflight participant who has twice been aboard the International Space Station
Chair

Rick Stroud, Film-maker and author of The Book of the Moon

Want to listen in?  The event is going to be live-streamed the stream link and more information can be found on the intelligencesquared.com site including Facebook and Twitter links.

NOTE: The talk is scheduled to begin at about 18:45 UTC that is 2:45 PM EDT. Be sure to check in a little earlier than that so you don’t miss anything.

NCBI ROFL: Colombo and the clitoris. | Discoblog

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“In 1559, the Italian anatomist Realdo Colombo (1515/6-1559) claimed to have “discovered” the clitoris. Closer scrutiny reveals that whilst he certainly emphasized the role of the clitoris in female sexuality, his claim to priority is unfounded. The clitoris had been known to Greek, Persian, and Arabic writers on medicine and surgery, albeit with misconceptions about its function. Colombo is best known for his definitive description of the pulmonary circulation but here too the question of priority is mired in controversy. Whilst Colombo was an extremely accomplished and successful anatomist, contemporary professional rivalry probably encouraged exaggerated claims of priority. Modern anatomical studies have greatly advanced our understanding of the surgical anatomy of the clitoris, optimising the ability to preserve its function during genital surgery.”

Photo: flickr/CarbonNYC

Related content:
Discoblog: NCBI ROFL: She might not be having what you think she’s having…
Discoblog: NCBI ROFL: And the most awkward sex of all time award goes to…
Discoblog:  NCBI ROFL: An electrophysiologic study of female ejaculation.

WTF is NCBI ROFL? Read our FAQ!


Friday Fluff – March 18th, 2011 | Gene Expression

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FF3

1) First, a post from the past: Evolution: What the Fossils Say and Why It Matters.

2) Weird search query of the week: “cheap pretty tutus.”

3) Comment of the week, in response to “Think Twins”:

An interesting point. No one can create another Hitler via cloning, nor a Charlemagne or even Mozart should their DNA be available in some way. The problems are many and are well illustrated with a car analogy… GM tries to produce exacting replicas of individual models thousands of times and they do this every year. Despite their efforts, quality varies, performance varies, endurance varies. No two vehicles of the same model are identical. Like a car has a driver, a human has a brain. Despite their similarities, identical twins are not identical in all ways.

They say that everyone has a twin somewhere. My friends met someone that looks nearly exactly like me. Yet other people have my same name. None of those people are me or even like me in meaningful ways. Cloning a human will get you a human which looks like another – nothing more. There is nothing special in that… until genetic ID ...

Weather Report From Titan: It’s Raining Methane (Hallelujah) | 80beats

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What’s the News: Images sent back from NASA’s Cassini spacecraft depict storm clouds and methane rain puddles, the first solid evidence of modern rainfall on Titan, Saturn’s largest moon. “We’re pretty confident that it has just rained on Titan,” lead author Elizabeth Turtle, from Johns Hopkins University Applied Physics Laboratory, told Wired. Astronomers have previous evidence of sulfuric-acid precipitation on Venus, but it doesn’t count as rainfall because it never reaches the surface.
What’s the Olds: Launched in 1997, Cassini arrived at Saturn’s orbit in 2004, where it started studying several of the planet’s moons.
As covered in 80beats, this wasn’t the first time scientists have thought about whether it rains on Titan.
80beats covered the 2008 discovery of the “ingredients of life” on Saturn’s moon Enceladus.
And the spacecraft has also caught the changing seasons on Titan’s surface.
Images reveal that these seasonal changes are so drastic that they affect the methane levels on Titan’s lakes. Not So Fast: Don’t read too much into these showers: Methane rain doesn’t mean life. The search continues.

Reference: “Rapid and Extensive Surface Changes Near Titan’s ...


Glimpses of the Fourth Domain? | The Loom

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Charles Darwin pictured evolution as a grand tree, with the world’s living species as its twigs. Scientists identify 10,000 new species a year, but they’ve got a long, long way to go before finding all of Earth’s biodiversity. So far, they have identified 1.5 million species of animals, but there may be 7 million or more in total. Beyond the animal kingdom, our ignorance balloons. Scoop up some sea water or a cup of soil, and there will likely be thousands of new species of microbes lurking there. Fortunately, a lot of the species that scientists discover each year are fairly close relatives to species we already know about. There may be plenty of beetle species left to be discovered, for example, but they will all end up as tufts sprouting from the same beetle branch.

Making matters more complicated is that the tree is, in some ways, more like a web. Genes sometimes slip from one species to another, especially among microbes. There are lots of ways this can happen. Viruses can ferry these genes from species to species; in other cases, microbes may just slurp up naked DNA. In the process, they blur genealogy.

This can be a hard concept ...


Kryptonite for the supermoon | Bad Astronomy

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[NOTE (added March 19): It occurs to me that some people might see the Moon rising today and think it looks HUGE because it's a "supermoon". However, it's far more likely they're falling victim to the famous Moon Illusion. You can read all about it here.]

If you believe the mainstream media, you might think this weekend’s "supermoon" will cause earthquakes, volcanoes, bad weather, halitosis, dust bunnies, and hangnails.

Guess what I think of this idea! Hint: check the name of my blog. Got it? Good.

In reality, this "supermoon" nonsense is, well, nonsense. I have some details below, but for those of you who are impatient (the tl;dr crowd) here are the bullet points:

Yes, the Moon is closer today than usual, but only by less than 2%.
This does happen around full Moon, which is when we get bigger tides, but that happens every single month. The Moon being closer amplifies that, but only a tiny little bit. The Moon’s possible effect on earthquakes has been studied for a long time. The result? Major earthquakes are not correlated with the Moon’s position or distance.

Therefore,

Anyone claiming this "supermoon" can cause ...


Success! NASA’s MESSENGER Becomes First Craft to Orbit Mercury | 80beats

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What’s the News: After firing its thrusters for about 15 minutes on Thursday, NASA’s MESSENGER spacecraft lost enough speed to be pulled in by Mercury’s gravitational field, making it the first probe to orbit the Swift Planet. “Mercury’s secrets, and the implications they hold for the formation and evolution of Earth-like planets, are about to be revealed,” MESSENGER principal investigator Sean Solomon told Slate.
What’s the Olds: Launched on 3 August 2004, MESSENGER (MErcury Surface, Space ENvironment, GEochemistry and Ranging spacecraft) has clocked 4.9 billion miles since day one—a trek that includes three Mercury fly-bys as it eased its way into orbit.
80beats published an image gallery of the stunning photos already sent back during the fly-bys and has covered such findings as ancient magma oceans and magnetic volcanoes.
In 2008, MESSENGER imaged most of the never-before-seen swaths of Mercury’s surface.
As Phil Plait points out, it’s not just Mercury that MESSENGER has photographed: It’s also sent long shots of Earth. Not So Fast: Don’t expect any stunning images by this weekend: MESSENGER’s first pictures in orbit are slated to arrive toward the end of the month.
The Future ...


U.S. Government Writes Software to Enable Squads of Propaganda Comment Trolls | Discoblog

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It sounds like the deranged words of a conspiracy theorist: The U.S. military is (not so) secretly creating software that’ll generate phony online personae in order to subtly influence social media conversations and spread propaganda. But what may sound like wacky theory is actually wacky reality, or at least will soon be, depending on whether it’s already in the works.

Dubbed the “online persona management service,” this technology would enable a single soldier to assume upwards of 10 different identities. As United States Central Command Commander Bill Speaks told The Guardian, “The technology supports classified blogging activities on foreign-language websites to enable Centcom to counter violent extremist and enemy propaganda outside the US.”

Once developed, the software could allow US service personnel, working around the clock in one location, to respond to emerging online conversations with any number of co-ordinated messages, blogposts, chatroom posts and other interventions. Details of the contract suggest this location would be MacDill air force base near Tampa, Florida, home ...