Falling Sky

Cool!

Cern lab goes 'colder than space'

A vast physics experiment built in a tunnel below the French-Swiss border is fast becoming one of the coolest places in the Universe.

The Large Hadron Collider is entering the final stages of being lowered to a temperature of 1.9 Kelvin (-271C; -456F) - colder than deep space.

The LHC has thousands of magnets which will be maintained in this frigid condition using liquid helium.

[...] Roberto Saban, the LHC's head of hardware commissioning, said that in order to obtain high magnetic fields without consuming too much power, the magnets were required to be "superconducting".

This is the property, exhibited by some materials at very low temperatures, to channel electrical current with zero resistance and very little power loss.

Helium exhibits spectacular properties at 2.2 Kelvin - becoming "superfluid". This allows it to conduct heat very rapidly, making it an extremely efficient refrigerant.

[...] When the LHC is switched on it will operate at an energy of five trillion electron-volts. It will then be shut down for the winter, so that the magnets can be "trained" to handle a beam run at seven trillion electron-volts.

Shriek! Green Ray!

While docked and onboard the International Space Station, a STS-123 Endeavour crew member captures the glowing green beauty of the Aurora Borealis March 21, 2008. (NASA/Reuters)

When Particles Collide

Anyone else getting really psyched up for May this year, when somebody presses the ON switch on this beautiful behemoth? Below is the core of one of the six LDHC experiments, the ATLAS detector, highlighted in today's APOD. The more you read, the more awesome it becomes - click on the picture below for a bogglingly big version in astounding detail.

ATLAS is one of two general-purpose detectors at the LHC. It will investigate a wide range of physics, including the search for the Higgs boson, extra dimensions, and particles that could make up dark matter. - CERN ATLAS page.

Photo: Maximilien Brice, CERN

The last pieces of the puzzle
Like the last pieces of a giant jigsaw puzzle, the final components of the titanic Large Hadron Collider (LHC) experiments at CERN are slotting into place. At ATLAS, CMS, ALICE and LHCb the remaining large pieces of equipment are being carefully lowered into the caverns in preparation for the start up later this year of the most powerful particle accelerator ever, the LHC.
At CERN, 100 metres underground in the countryside outside Geneva, the LHC and its four big experiments are stuffed full of some of the most complex scientific apparatus in the world. On the surface the assembly hangers are beginning to look eerily empty, but below a vision of mind-boggling complexity is now almost fully formed.
[...] The next few weeks will be an emotional time at CERN. The product of some 15 years of work is coming to fruition and tensions are riding high as the equipment is tested. Soon, the first protons will be smashed together and the secrets of our universe will begin to unravel.

Three months to go! Cannae wait!

The Destroyer of Galaxies

NASA Announces Discovery of Assault by a Black Hole

A powerful jet from a supermassive black hole is blasting a nearby galaxy, according to new data from NASA observatories. This never-before witnessed galactic violence may have a profound effect on planets in the jet's path and trigger a burst of star birth in its destructive wake.

This real-life scene, worthy of the most outlandish science fiction, is playing out in a faraway binary galaxy system known as 3C321. Two galaxies are in orbit around one another. A supermassive black hole at the core of the system's larger galaxy is spewing a jet in the direction of its smaller companion.

"We've seen many jets produced by black holes, but this is the first time we've seen one punch into another galaxy," says Dan Evans, a scientist at the Harvard-Smithsonian Center for Astrophysics and leader of the study. "This jet could be causing all sorts of problems for the smaller galaxy it is pummeling."

Jets from super massive black holes produce large amounts of radiation, especially high-energy X-rays and gamma-rays, which can be lethal in large quantities. The combined effects of this radiation and particles traveling at almost the speed of light could severely damage the atmospheres of planets lying in the path of the jet. For example, protective layers of ozone in the upper atmosphere of planets could be destroyed.

The effect of the jet on the companion galaxy is likely to be substantial, because the galaxies in 3C321 are extremely close at a distance of only about 20,000 light years apart. They lie approximately the same distance as Earth is from the center of the Milky Way galaxy.

Sky1K

Guess what?  It's the 1000th post on this here website.  Hurrah!  Rather than celebrate with monotonous burbling, nonsensical rambling or other syllable-rich words, I'll just let the night sky do the talking.  Here's to the next ton.

Credit: NASA, ESA, and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration

Resembling festive lights on a holiday wreath, this NASA/ESA Hubble Space Telescope image of the nearby spiral galaxy M74 is an iconic reminder of the impending season. Bright knots of glowing gas light up the spiral arms, indicating a rich environment of star formation.

Messier 74, also called NGC 628, is a stunning example of a "grand-design" spiral galaxy that is viewed by Earth observers nearly face-on. Its perfectly symmetrical spiral arms emanate from the central nucleus and are dotted with clusters of young blue stars and glowing pink regions of ionized hydrogen (hydrogen atoms that have lost their electrons). These regions of star formation show an excess of light at ultraviolet wavelengths. Tracing along the spiral arms are winding dust lanes that also begin very near the galaxy's nucleus and follow along the length of the spiral arms.

M74 is located roughly 32 million light-years away in the direction of the constellation Pisces, the Fish. It is the dominant member of a small group of about half a dozen galaxies, the M74 galaxy group. In its entirety, it is estimated that M74 is home to about 100 billion stars, making it slightly smaller than our Milky Way.

Twinkle Twinkle

Star Cluster Bursts into Life in New Hubble Image

Thousands of sparkling young stars are nestled within the giant nebula NGC 3603. This stellar "jewel box" is one of the most massive young star clusters in the Milky Way Galaxy.

NGC 3603 is a prominent star-forming region in the Carina spiral arm of the Milky Way, about 20,000 light-years away. This latest image from NASA's Hubble Space Telescope shows a young star cluster surrounded by a vast region of dust and gas.

The image reveals stages in the life cycle of stars.

Powerful ultraviolet radiation and fast winds from the bluest and hottest stars have blown a big bubble around the cluster. Moving into the surrounding nebula, this torrent of radiation sculpted the tall, dark stalks of dense gas, which are embedded in the walls of the nebula. These gaseous monoliths are a few light-years tall and point to the central cluster. The stalks may be incubators for new stars.

On a smaller scale, a cluster of dark clouds called "Bok" globules resides at the top, right corner. These clouds are composed of dense dust and gas and are about 10 to 50 times more massive than the Sun. Resembling an insect's cocoon, a Bok globule may be undergoing a gravitational collapse on its way to forming new stars.

The Ring, Precious!

Hubble Finds Ring of Dark Matter

Astronomers using NASA's Hubble Space Telescope have discovered a ghostly ring of dark matter that formed long ago during a titanic collision between two massive galaxy clusters.

The ring's discovery is among the strongest evidence yet that dark matter exists. Astronomers have long suspected the existence of the invisible substance as the source of additional gravity that holds together galaxy clusters. Such clusters would fly apart if they relied only on the gravity from their visible stars. Although astronomers don't know what dark matter is made of, they hypothesize that it is a type of elementary particle that pervades the universe.

[...] "By studying this collision, we are seeing how dark matter responds to gravity," said team member Holland Ford of Johns Hopkins University. "Nature is doing an experiment for us that we can't do in a lab, and it agrees with our theoretical models."

Dark matter makes up most of the universe's material. Ordinary matter, which makes up stars and planets, comprises only a few percent of the universe's matter.

Tracing dark matter is not an easy task, because it does not shine or reflect light. Astronomers can only detect its influence by how its gravity affects light. To find it, astronomers study how faint light from more distant galaxies is distorted and smeared into arcs and streaks by the gravity of the dark matter in a foreground galaxy cluster, a powerful trick called gravitational lensing. By mapping the distorted light, astronomers can deduce the cluster's mass and trace how dark matter is distributed in the cluster.

"The collision between the two galaxy clusters created a ripple of dark matter that left distinct footprints in the shapes of the background galaxies," Jee explained. "It's like looking at the pebbles on the bottom of a pond with ripples on the surface. The pebbles' shapes appear to change as the ripples pass over them. So, too, the background galaxies behind the ring show coherent changes in their shapes due to the presence of the dense ring."

Celestial Doves

The Seven Sisters Pose for Spitzer -- and for You!

The Seven Sisters, also known as the Pleiades, seem to float on a bed of feathers in a new infrared image from NASA's Spitzer Space Telescope. Clouds of dust sweep around the stars, swaddling them in a cushiony veil.

[...] The Pleiades, located more than 400 light-years away in the Taurus constellation, are the subject of many legends and writings. Greek mythology holds that the flock of stars was transformed into celestial doves by Zeus to save them from a pursuant Orion. The 19th century poet Alfred Lord Tennyson described them as "glittering like a swarm of fireflies tangled in a silver braid."

The star cluster was born when dinosaurs still roamed the Earth, about 100 million years ago. It is significantly younger than our 5-billion-year-old sun. The brightest members of the cluster, also the highest-mass stars, are known in Greek mythology as two parents, Atlas and Pleione, and their seven daughters, Alcyone, Electra, Maia, Merope, Taygeta, Celaeno, and Asterope. There are thousands of additional lower-mass members, including many stars like our sun. Some scientists believe that our sun grew up in a crowded region like the Pleiades, before migrating to its present, more isolated home.

The new infrared image from Spitzer highlights the "tangled silver braid" mentioned in the poem by Tennyson. This spider-web-like network of filaments, colored yellow, green and red in this view, is made up of dust associated with the cloud through which the cluster is traveling. The densest portion of the cloud appears in yellow and red, and the more diffuse outskirts are shown in green hues. One of the parent stars, Atlas, can be seen at the bottom, while six of the sisters are visible at top. Additional stars in the cluster are sprinkled throughout the picture in blue.

Planetary Geometry

Bizarre Hexagon Spotted on Saturn

One of the most bizarre weather patterns known has been photographed at Saturn, where astronomers have spotted a huge, six-sided feature circling the north pole.

Rather than the normally sinuous cloud structures seen on all planets that have atmospheres, this thing is a hexagon.

[...] This is a very strange feature, lying in a precise geometric fashion with six nearly equally straight sides," said Kevin Baines, atmospheric expert and member of Cassini's visual and infrared mapping spectrometer team at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We've never seen anything like this on any other planet. Indeed, Saturn's thick atmosphere, where circularly-shaped waves and convective cells dominate, is perhaps the last place you'd expect to see such a six-sided geometric figure, yet there it is."

The hexagon is nearly 15,000 miles (25,000 kilometers) across. Nearly four Earths could fit inside it. The thermal imagery shows the hexagon extends about 60 miles (100 kilometers) down into the clouds.

Video footage here.  Photo credit: NASA/JPL/University of Arizona

What Lies Beneath...

NZ fishermen land colossal squid

New Zealand fishermen have caught what is expected to be a world-record-breaking colossal squid.

Fisheries Minister Jim Anderton said the squid, weighing an estimated 450kg (990lb),took two hours to land in Antarctic waters.

Local news said the Mesonychoteuthis hamiltoni was about 10m (33ft) long, and was the first adult colossal squid landed intact.

[...] Colossal squid, which are found deep in Antarctic waters, are thought to be about the same length as giant squid (Architeutis dux) but are much heavier.

The species was first identified in 1925, but very few specimens have been found.