Posted on by Tammy Plotner

Happy Birthday, Sir William Herschel!

On this day in 1738, an astronomy legend was born – Sir William Herschel. Among this British astronomer and musician’s many accomplishments, Herschel was credited with the discovery of the planet Uranus in 1781; detecting the motion of the Sun in the Milky Way in 1785; finding Castor’s binary companion in 1804 – and he was the first to record infrared radiation. Herschel was well known as the discoverer of many clusters, nebulae, and galaxies. This came through his countless nights studying the sky and writing catalogs whose information we still use today. Let’s take a brief, closer look at just who he was…

Born as Frederick William Herschel, this Hanover, Germany native had nine brothers and sisters. During his teenage years, he and his brother, Jakob, were oboists in a military band. When war ensued, his father sent the pair to England to escape. Once there, Herschel continued his musical career by playing cello and harpsichord – eventually composing 24 symphonies, a handful of concertos and religious music. He continued to be a musician, with many appointments, until middle age. Most of his family also migrated to England, the most famous of which is his sister Caroline, who came to live with him in 1772.

But it wasn’t music that was Herschel’s passion. After he met English Astronomer Royal Nevil Maskelyne, he began construction on his own reflector telescope, spending up to 16 hours a day grinding and polishing the speculum metal primary mirrors. By age 35 he’d begun his astronomical journey in earnest – and a year later he began recording his observations from the Great Orion Nebula to the rings of Saturn. Sir William’s interest was taken by the study of double stars and with a 160mm telescope of his own construction, he began a systematic search for binaries among “every star in the Heavens” in October, 1779 and continued listing discoveries through 1792, eventually compiling three catalogs.

During this time he continued to support himself and his sister with his music. In her biography, Caroline recounts how he would rush home between acts to scan the skies – and how she often had to clean pitch from mirror-making from his clothes to make him presentable. From 1782 to 1802, Sir William swept the skies, recording all he saw and sharing his discoveries with other astronomers. So devoted was he, that he even gave Caroline her own telescope in 1783, encouraging her to also make her own observations and discoveries. Herschel published his discoveries as three catalogues, a walloping 2400 entries, filled with distant nebulae and cosmic wonders. Over the time of his astronomical career, Herschel constructed more than four hundred telescopes – the most famous of which had an almost 50 inch diameter mirror and a 40 foot focal length!

In later years, he and Caroline moved on to Windsor Road in Slough… a residence which would eventually be come to known as “Observatory House”. It was during this time he married and eventually had a son – John. Caroline also moved on, yet continued to be his secretarial assistant. Sir William’s astronomical career was quite illustrious – so much so that this article only highlights a few of his accomplishments. He observed and recorded the satellites of his discovery, Uranus, along with more obscure moons belonging to Saturn. He did work with infrared radiation, popularized the term “asteroid”, studied the martian polar caps – revealing them as seasonal – and may very well have been the first to discover the rings of Uranus. His lack of a formal “astronomical education” never slowed Sir William Herschel down!

“I have looked further into space than ever human being did before me. I have observed stars of which the light, it can be proved, must take two million years to reach the Earth.”

Herschel’s life ended at a ripe old age of 84… Passing on at his beloved Observatory House. His son, John Herschel, would carry on in his father’s footsteps and also became a famous astronomer. While few of us will ever be able to match Herschel’s passion for astronomy, at least we can take a moment to look at the stars and wish this astronomy “great” a very happy birthday!

Posted on by Paul Scott Anderson

Is There a Methane Habitable Zone?

A sunlight glint off a methane lake near Titan’s north pole (infrared image). Credit: NASA/JPL/University of Arizona/DLR

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For a long time now, we have heard the mantra “follow the water” when it comes to searching for life elsewhere. Life as we know it here on Earth requires liquid water, whether it is tiny microbes or elephants. It has thus been assumed that carbon-based life somewhere else that is basically similar to ours in its chemical makeup (another assumption) would also require water for its survival and growth. But is that necessarily true? In recent years, more consideration has been given to the possibility that life could develop in other mediums as well, besides water. A liquid is still ideal, for allowing the necessary molecules to bond together. So what are the alternatives? Well, one of the most interesting possibilities is something we have already seen now elsewhere in our solar system – liquid methane.

It should be noted that the importance of water cannot be overlooked. According to Chris McKay, an astrobiologist and planetary scientist at NASA’s Ames Research Center, “We live on a planet where water is a liquid and we have adapted and evolved to work with that liquid. Life has very cleverly used the properties of water to do things not just in terms of solution, but in using the strong polarity of that solution to its advantage in terms of hydrophobic and hydrophilic bonds, and using the very structure of water to help align molecules.”

But McKay also published a paper In the journal Planetary and Space Science last April, postulating how life on some worlds could use liquid methane in place of water. There could be planets orbiting red dwarf stars, which are smaller and cooler than our Sun, and could have a “liquid methane habitable zone” where methane could exist as a liquid on the surface of planets orbiting within that zone. They could also exist around Sun-like stars, although they would be easier to detect around the smaller, dimmer red dwarf stars. But there is already one methane world that we know of, much closer to home…

Orbiting the sixth planet out from the Sun, Saturn, is a moon which in some ways is eerily Earth-like, with rain, rivers, lakes and seas – Titan. It is the first world we’ve found so far that has liquid on its surface like Earth does. But there is one major difference; the liquid is not water, it is liquid methane/ethane. With temperatures far colder than anywhere on Earth at –179 degrees Celsius, water cannot exist as a liquid, it is frozen as hard as rock. But methane can exist as a liquid under those conditions and indeed does on Titan. Beneath an atmosphere that is thicker than ours (but also made primarily of nitrogen), the surface of Titan has been modified in much the same way as Earth’s; liquid methane plays the same role there as water does here, with a complete hydrological cycle. It is like a familiar-looking but colder version of our planet, which has raised the question of whether an environment like this could even support life of some kind.

McKay had also previously suggested that methane-based life could consume hydrogen, acetylene and ethane, and exhale methane instead of carbon-dioxide. This would result in a depletion of hydrogen, acetylene and ethane on the surface of Titan. Interestingly, this is just what has been found by the Cassini spacecraft, although McKay is quick to caution that there could still be other more likely explanations. There is still a lot we don’t know about Titan. Whatever the explanation, there is some interesting chemistry going on.

At the very least, Titan is thought to represent conditions similar to those on the early Earth, a sort of primordial Earth in deep-freeze. That alone could provide vital clues as to how to life took hold on our planet. If there are other planets or moons out there that are similar, as now seems likely, they could also reveal valuable insights into the question of the origin of life, whether there is anything swimming in those cold lakes and seas or not. While water is still considered the primary liquid medium of choice, liquid methane could be the next best thing, and if we have learned anything, it is how amazingly adaptive and resourceful life can be, perhaps even more than we think.

Posted on by Nancy Atkinson

Activity on the Sun Ramps Up with Monster Prominences; Huge Filament Snaps

A large protuberance on the Sun, from Nov. 13, 2011. Credit: César Cantú, Chilidog Observatory.

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A huge wall of plasma rose from the Sun’s southeast limb over the weekend, with what might be one of the biggest prominences seen in many years. César Cantu from Monterrey, Mexico, took the image above, adding an “Earth” for reference of how big this prominence really is. A solar prominence is a large, bright feature extending outward from the Sun’s surface. Prominences are anchored to the Sun’s surface in the photosphere, and can loop hundreds of thousands of kilometers into space.

Leonard Mercer from Malta sent us the image below, saying “I never encountered such a huge prominence since I started imaging the Sun.”

A mosaic of 4 images taken of the Sun on Nov. 13, 2011. Credit: Leonard Mercer.

As large as this prominence is, there was also another even larger feature on the Sun. A filament (which is a prominence that is viewed against the solar disk) on the upper left snakes across the Sun’s surface, stretching more than a million km or about three times the distance between Earth and the Moon.

The video below from the Solar Dynamics Observatory shows the filament intact at first, and then later, from 13:00 to 16:00 UT on November 14, 2011, the filament shoots up from the Sun’s surface and snaps apart.

The SDO team explains that the red-glowing looped material is plasma, a hot gas comprised of electrically charged hydrogen and helium. The prominence plasma flows along a tangled and twisted structure of magnetic fields generated by the Sun’s internal dynamo. An erupting prominence occurs when such a structure becomes unstable and bursts outward, releasing the plasma.

Despite all this activity, there hasn’t been much as far as solar flares, but Spaceweather.com encourages anyone with solar telescopes to monitor developments.

Posted on by Ken Kremer

China completes 2nd Docking to Space Lab and sets Path to Manned flights in 2012

Photo taken on Nov. 14, 2011 shows the image of Shenzhou-8 spacecraft on the electronic screen in the Beijing Aerospace Flight Control Center, in Beijing, China. The image was shot by a video camera on Tiangong-1 just after Shenzhou-8's separation from Tiangong-1. China's Shenzhou-8 unmanned spacecraft successfully re-docked with the Tiangong-1, a module of the country's planned space lab on Monday, Nov. 14, 2011 Credit: Xinhua/Wang Jianmin

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Chinese space prowess took another major leap forward today (Nov. 14) when the unmanned Shenzhou-8 capsule successfully re-docked with China’s Tiangong-1 space lab while speeding through space and orbiting some 343 km above Earth. Today’s events pave the way for China to rapidly ramp up their human space program and loft up to two manned flights to the space lab module in 2012.

The re-docking marked only the 2nd time that China had accomplished a successful space docking, a critical technical milestone that opens the door to China’s real ambition of assembling a 100 ton operational Space Station in low Earth orbit by 2020 – about the time when the ISS might be decommissioned.

China made space history on Nov. 3 by becoming only the 3rd country on Earth – after the US and the Russia – to accomplish a space link up when Shenzhou- 8 and Tiangong-1 rendezvoused and docked in earth orbit.

The graphics shows the procedure of the second docking between Shenzhou-8 spacecraft and Tiangong-1 space lab module on Nov. 14, 2011. Credit: Xinhua/Lu Zhe

Shenzhou-8 was launched to orbit on Nov. 1 atop a Long March 2F booster rocket from the Jiuquan Satellite Launch Center in the Gobi Desert in northwest China. The two Chinese built spacecraft have been joined together for 12 days.

China’s space re-docking exercise today came just hours after Russia successfully launched their Soyuz capsule with two Russians and one American bound for the ISS.

Views of Shenzhou-8 spacecraft docking with the space lab module Tiangong-1 for the second time on Nov. 14, 2011. Credit: CCTV/Beijing Aerospace Control Center

Today’s goal was to give Chinese engineers more practice and confidence in mastering the complex maneuvers required for rendezvous and docking two vehicles in space. It was carried out in daylight conditions as opposed to the nighttime conditions for the initial docking to expand the testing envelope under different scenarios.

Shenzhou-8 first disengaged from the prototype space station at about 6:37 a.m. EST and then withdrew to a distance of about 140 meters (460 ft). About 30 minutes later, mission controllers at the Beijing Aerospace Control Center monitored Shenzhou-8 as it automatically approached Tiangong-1 and completed the second docking – or “Space Kiss” as the Chinese media fondly say – at about 6:53 a.m. EST.

Photo taken on Nov. 14, 2011 show the live video of the outside view of Shenzhou-8 on a giant screen in the Beijing Aerospace Flight Control Center, in Beijing, capital of China, Nov. 14, 2011. China's Shenzhou-8 unmanned spacecraft successfully re-docked with the Tiangong-1, a module of the country's planned space lab on Monday. Credit: Xinhua/Wang Jianmin

The combined Shenzhou-8/Tiangong-1 orbiting complex is some 20 meter in length and weighs about 16 tons. Each vehicle weighs some 8 tons. Tiangong-1 is 10.4 m in length and 3.3. m in diameter. Shenzhou-8 is 9.2 m in length

Shenzhou is China’s manned space capsule but flew this flight with no humans aboard because Chinese space officials felt it was safer and prudent and did not want to expose astronauts to excessive risk during the unprecedented docking attempts.

Following today’s complete success, the China Manned Space Engineering (CMSE) Project is pushing ahead with plans to launch up to two manned missions to Tiangong-1 in 2012 – namely Shenzhou-9 and Shenzhou-10 which are already under construction.

Both 2012 missions would be short duration flights of a few days or weeks since the Tiangong-1 module is a prototype space station module and not outfitted for long duration flights.

CMSE is evaluating a pool of Chinese astronauts already in training – including two women – for the two flights. Both women candidates are married and about 30 years of age but have not been publically identified.

It seems highly likely that one of the Shenzhou missions will include the first female Chinese astronaut.

So far China has launched six astronauts on three manned Shenzhou capsules between 2003 and 2008.

The docking mechanism on Shenzhou-8 was developed and manufactured in China, says Wu Ping, spokeswoman for the CMSE.

In two days, Shenzhou-8 is due to undock from Tiangong-1 for the final time and initiate the fiery re-entry to Earth on Nov. 17. The descent capsule will land by parachute.

These historic feats prove that China’s manufacturing and technological capabilities are surging forward and rapidly matching the Western powers and Japan in a broad swath of scientific and technical fields.

Since the forced retirement of NASA’s functioning space shuttle orbiters, only China and Russia can launch people into space.


Video animation caption: Chinese spacecraft to ‘kiss’ in space. Credit: NMANewsDirect

Read Ken’s features about Shenzhou-8 & Tiangong-1
China Technology Surges Forward with Spectacular First Docking in Space
China launches Shenzhou-8 bound for Historic 1st Docking in Space
Shenzhou-8 rolled out for Blastoff to China’s 1st Space Station on November 1
Bizarre Video: China’s Tiangong 1 Space Lab Animation set to ‘America the Beautiful’ Soundtrack
China Blasts First Space Lab Tiangong 1 to Orbit
China set to ‘Leap Forward in Space’ as Tiangong 1 Rolls to Launch Pad

Posted on by David Warmflash

Update on Phobos-Grunt: Might the LIFE Experiment be Recovered?

Phobos-Grunt
An artists concept of the Phobos-Grunt Mission. Credit: Roscosmos

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Editor’s note: With Russian engineers trying to save the Phobos-Grunt mission, Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the spacecraft, provides an update of the likelihood of saving the mission, while offering the intriguing prospect that their experiment could possibly be recovered, even if the mission fails.

With the latest word from Roscosmos being that the Mars moon probe, Phobos-Grunt is “not officially lost,” but yet remains trapped in low Earth orbit, people are wondering what may happen over the next several weeks. Carried into space early Wednesday morning, November 9, Moscow time, atop a Zenit 2 rocket, Grunt, Russian for “soil”, entered what is known in space exploration as a parking orbit. After the engine of the Zenit upper stage completed its burn, it separated from another stage, known as Fregat, which now still remains attached to Phobos-Grunt. Ignition of the Fregat engine was to occur twice during the first five hours in space. The first Fregat burn would have taken the spacecraft to a much higher orbit; the second burn, about 2.5 hours later would have propelled the probe on its way to Mars and its larger moon, Phobos. From this moon, a sample of soil would be scooped into a special capsule which would return to Earth for recovery in 2014.

Grunt is still in a low orbit, because neither Fregat burn occurred. While the spacecraft is believed to be in safe mode and even has maneuvered such that its orbital altitude has increased, controllers have been unable to establish contact to send new commands. If communication cannot be established, it will re-enter the atmosphere.

In addition to the sample return capsule, Grunt carries an instrument package designated to remain on the Phobosian surface, plus a Chinese probe, Yinghuo-1, designed to orbit Mars. The mission also includes the Planetary Society’s Living Interplanetary Flight Experiment (LIFE) , for which I serve as principal science lead of the US team. Carried inside the return capsule into which the Phobosian soil is to be deposited, LIFE consists of a discoid-shaped canister, a biomodule, weighing only 88 grams. Inside are 30 sample tubes carrying ten biological species, each in triplicate. Surrounded by the 30 tubes is a sample of soil with a mixed population of microorganisms, taken from the Negev desert in Israel to be analyzed by Russian microbiologists.

The Planetary Society’s Living Interplanetary Flight Experiment (LIFE) capsule, on board the Phobos-Grunt spacecraft. Credit:The Planetary Society

Organisms carried within the LIFE biomodule include members of all three domains of Earth life: bacteria, archaea, and eukaryota. The purpose of the experiment is to test how well the different species can endure the space environment, akin to microorganisms moving in space within a meteoroid ejected from Mars by an impact event. If organisms can remain viable within rock material that is transferred naturally from Mars to Earth, it would lend support to the Mars transpermia hypothesis –the idea that life on Earth may have began by way of a seeding event by early organisms from Mars.

We know of microorganisms that could survive the pressures and temperatures associated with the ejection itself. We also know that during atmospheric entry, only the most outer few millimeters of rocks are heated on their way to Earth; thus, anything alive in a rock’s interior at this point should still be alive when the rock hits Earth as a meteorite. If life forms also could survive the journey itself from Mars to Earth, a Martian origin for Earth’s life would be a major possibility. It also would mean that life originating on its own anywhere in the Cosmos could spread from each point of origin, thus increasing the number of living planets and moons that may exist.

Numerous studies of the survivability of many of the LIFE species have been conducted in low Earth orbit, but much of the challenge to life in space comes from highly energetic space radiation. A large portion of space radiation is trapped by a system of magnetic fields known as the Van Allen radiation belts, or the geomagnetosphere. Since very few controlled studies of microorganisms, plant seeds, and other life have been conducted beyond the Van Allen belts, which reach an altitude of about 60,000 kilometers (about 1/7th the distance to the Moon), the Planetary Society arranged to have the LIFE biomodule carried within Grunt’s return capsule.

Over last weekend, the spacecraft surprised everyone by maneuvering on its own, raising its orbit. Due to this, the estimated reentry date was moved back from late November to mid January, meaning that the LIFE biomodule will be in space for more than nine weeks. An intriguing possibility that looms as controllers consider how the mission might end is that the Grunt sample return capsule will break off from the rest of the craft intact. If this happens, it could assume the stable atmospheric entry, descent, and landing that were expected after the return from Phobos. If this happens and the capsule comes down on land, we could recover the LIFE biomodule and test the state of the organisms packaged within it. The result of yet another biological test in low orbit, it would not be the experiment of our dreams. But, amidst the loss of a mission into which so many engineers and scientists have invested their dreams, a little bit could mean a lot.

Posted on by Nancy Atkinson

How to Drive Space Shuttle Endeavour Down the Streets of Los Angeles

Even though the space shuttle is capable of circling the Earth in just 90 minutes, getting Space Shuttle Endeavour to travel the final 22 km (14 miles) to its ultimate resting place will take over 13 hours — not to mention a huge community effort. It’s not everyday the nearly six-story, 82,000 kg (180,0000 lb) spacecraft — with a 24-meter (78-foot) wing span — takes to the streets of any city, not to mention the famous freeways of Los Angeles, California. But now that the shuttles are retired and will be heading to museums, the cities that will be home to the four remaining space shuttles are figuring out the logistics of transporting these huge spacecraft through their streets. So, just how exactly do you drive a space shuttle from the LAX airport to the California Science Center? Slowly. Very slowly — even by L.A. traffic standards.

LA TV station KCET’s news magazine show, SoCal Connected shared this report with Universe Today, explaining what it will take to get Endeavour “home” by late 2012.

Decommissioning and transporting — $28 million.
Building a new museum wing and exhibit — $170 million.
Owning a piece of space history — priceless.

Here’s a cool timelapse from the LA Times:

Posted on by Tammy Plotner

Unifying The Quantum Principle – Flowing Along In Four Dimensions

PASIEKA/SPL

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In 1988, John Cardy asked if there was a c-theorem in four dimensions. At the time, he reasonably expected his work on theories of quantum particles and fields to be professionally put to the test… But it never happened. Now – a quarter of a century later – it seems he was right.

“It is shown that, for d even, the one-point function of the trace of the stress tensor on the sphere, Sd, when suitably regularized, defines a c-function, which, at least to one loop order, is decreasing along RG trajectories and is stationary at RG fixed points, where it is proportional to the usual conformal anomaly.” said Cardy. “It is shown that the existence of such a c-function, if it satisfies these properties to all orders, is consistent with the expected behavior of QCD in four dimensions.”

His speculation is the a-theorem… a multitude of avenues in which quantum fields can be energetically excited (a) is always greater at high energies than at low energies. If this theory is correct, then it likely will explain physics beyond the current model and shed light on any possible unknown particles yet to be revealed by the Large Hadron Collider (LHC) at CERN, Europe’s particle physics lab near Geneva, Switzerland.

“I’m pleased if the proof turns out to be correct,” says Cardy, a theoretical physicist at the University of Oxford, UK. “I’m quite amazed the conjecture I made in 1988 stood up.”

According to theorists Zohar Komargodski and Adam Schwimmer of the Weizmann Institute of Science in Rehovot, Israel, the proof of Cardy’s theories was presented July 2011, and is slowly gaining notoriety among the scientific community as other theoretical physicists take note of his work.

“I think it’s quite likely to be right,” says Nathan Seiberg, a theoretical physicist at the Institute of Advanced Study in Princeton, New Jersey.

The field of quantum theory always stands on shaky ground… it seems that no one can be 100% accurate on their guesses of how particles should behave. According to the Nature news release, one example is quantum chromodynamics — the theory of the strong nuclear force that describes the interactions between quarks and gluons. That lack leaves physicists struggling to relate physics at the high-energy, short-distance scale of quarks to the physics at longer-distance, lower-energy scales, such as that of protons and neutrons.

“Although lots of work has gone into relating short- and long-distance scales for particular quantum field theories, there are relatively few general principles that do this for all theories that can exist,” says Robert Myers, a theoretical physicist at the Perimeter Institute in Waterloo, Canada.

However, Cardy’s a-theorem just might be the answer – in four dimensions – the three dimensions of space and the dimension of time. However, in 2008, two physicists found a counter-example of a quantum field theory that didn’t obey the rule. But don’t stop there. Two years later Seiberg and his colleagues re-evaluated the counter-example and discovered errors. These findings led to more studies of Cardy’s work and allowed Schwimmer and Komargodski to state their conjecture. Again, it’s not perfect and some areas need further clarification. But Myers thinks that the proof is correct. “If this is a complete proof then this becomes a very powerful principle,” he says. “If it isn’t, it’s still a general idea that holds most of the time.”

According to Nature, Ken Intriligator, a theoretical physicist at the University of California, San Diego, agrees, adding that whereas mathematicians require proofs to be watertight, physicists tend to be satisfied by proofs that seem mostly right, and intrigued by any avenues to be pursued in more depth. Writing on his blog on November 9, Matt Strassler, a theoretical physicist at Rutgers University in New Brunswick, New Jersey, described the proof as “striking” because the whole argument follows once one elegant technical idea has been established.

With Cardy’s theory more thoroughly tested, chances are it will be applied more universally in the areas of quantum field theories. This may unify physics, including the area of supersymmetry and aid the findings with the LHC. The a-theorem “will be a guiding tool for theorists trying to understand the physics”, predicts Myers.

Pehaps Cardy’s work will even expand into condensed matter physics, an area where quantum field theories are used to elucidate on new states of materials. The only problem is the a-theorem has only had proof in two and four dimensions – where a few areas of condensed matter physics embrace layers containing just three dimensions – two in space and one in time. However, Myers states that they’ll continue to work on a version of the theorem in odd numbers of dimensions. “I’m just hoping it won’t take another 20 years,” he says.

Original Story Source: Nature News Release. For Further Reading: On Renormalization Group Flows in Four Dimensions.

Posted on by Nancy Atkinson

Timelapse: The Spirit Rover’s Entire Journey on Mars

In just under 3 minutes, this timelapse video uses 3,418 different images taken by Spirit’s front-right Hazcam to give an overview of her mission — from waking up and driving off the lander back in January, 2004 to studying countless rocks, climbing up (and down) Husband Hill, studying more rocks, trekking across Gusev Crater, stirring up some interesting light-colored soil, to ultimately getting stuck not being able to get out. This time-lapse covers 7.25 km (4.8 miles) of driving over the course of 5 years, 3 months, 27 days, all played back at 24 frames per second.

Via @SpaceFuture

Posted on by Tammy Plotner

LISA Pathfinder – Surfing Gravity Waves

LISA Pathfinder about to enter the space environment vacuum test. Credit: ESA

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Do you remember the LISA mission? I do! The proposed launch for this unique vision is slated for 2014 and the latest sensor technology is making its own waves… by being far more accurate than expected. Now ESA’s LISA Pathfinder mission is better than ever, and ready to tackle the vast ocean of space in search of elusive gravitational waves…

So what’s new? By employing a near complete version of LISA, the Optical Meteorology Subsystem passed its first test under space-like temperature and vacuum conditions. Not only did it make the grade, but it went far beyond. It surpassed the precision requirement needed to detect gravitational waves by 300%!

Einstein predicted them, but to physically record this phenomenon in space, the LISA Pathfinder will utilize a laser to measure the distance between two free-floating gold–platinum cubes. Here on the ground, the team in Ottobrunn, Germany, are performing the tests using mirrors instead of cubes. Not only will the distance between them be cataloged, but their angles with respect to the laser beams. Is LISA good? Darn right. She had an accuracy rating of 10 billionths of a degree!

LISA Pathfinder with scientists in the clean room test environment. Credits: Astrium UK
“This is equivalent to the angle subtended by an astronaut’s footprint on the Moon!” notes Paul McNamara, Project Scientist for the LISA Pathfinder mission.

So how are gravitational waves detected? If perfect conditions do exist in space, then the free-floating cubes should mirror each other’s motions. Now, enter Einstein’s general theory of relativity. If some gravitational event should occur – such as the collision of two black holes – this should cause a minute distortion in the fabric of space. These tiny changes should be detectable. However, the accuracy needed to record such an event would need to be about one hundredth the size of an atom… a size called a “picometre”. Originally, LISA was optimized at 6 picometres measured over a timeline of 1000 seconds. But she bettered her record in 2010 and has now reached an amazing accuracy level of 2 picometres.

“The whole team has worked extremely hard to make this measurement possible,” said Dr McNamara. “When LISA Pathfinder is launched and we’re in the quiet environment of space some 1.5 million km from Earth, we expect that performance will be even better.”

Final preparation work on LISA Pathfinder ahead of the space environment testing. Credits: Astrium UK
The instrument team from Astrium GmbH, the Albert Einstein Institute and ESA are testing the Optical Metrology Subsystem during LISA Pathfinder thermal vacuum tests in Ottobrunn by spacecraft prime contractor Astrium (UK) Ltd. Tentatively set to launch in mid-2014, the LISA Pathfinder is well on its way to ride the gravitational waves and set the pace for ESA’s New Gravitational Wave Observatory. Perhaps within the next 10 years we’ll see even more advancements in finding the “final piece in Einstein’s cosmic puzzle.”

Way to go, LISA!

Original Story Source: ESA News Release.

Posted on by Tammy Plotner

Leonid Meteor Shower Peaks – November 17-19, 2011

Leonid meteors seen from 39,000 feet aboard an aircraft during the 1999 Leonids Multi-Instrument Aircraft Campaign (Leonid-MAC). Comet Tempel-Tuttle provides the cometary debris for the Leonid meteor storm, which takes place in mid-November. Credit: NASA/ISAS/Shinsuke Abe and Hajime Yano

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Are you ready for a good, predictable meteor shower? Then break out your favorite skywatching gear because the 2011 Leonid meteor shower is already sparkling the skies…

In the pre-dawn hours on the mornings of November 17-19th, the offspring of Comet Temple/Tuttle will be flashing through our atmosphere at speeds of up to 72 kilometers per second – and enticing you to test your meteor watching skills against partially moonlit skies. Although the waning Moon will greatly interfere with fainter meteor trails, don’t let that stop you from enjoying early evening observations, or enjoying your morning coffee with a handful of “shooting stars” which will be emanating outward from the constellation of Leo.

Where in the skies do you look? For all observers the constellation of Leo is along the ecliptic plane and will be near its peak height during best viewing times. When? Because of the Moon, earlier evening observations are favored (before local midnight), but just a couple of hours before local dawn is the best time to watch. Why? Read on!

Although it has been a couple of years since Temple/Tuttle was at perihelion, don’t forget that meteor showers are wonderfully unpredictable and the Leonids are sure to please with fall rate of around 20 (average) per hour. Who knows what surprises it may bring! Each time the comet swings around our Sun it loses some of its material in the debris trail. Of course, we all know that is the source of a meteor shower, but what we don’t know is just how much debris was shed and where it may lay.

“The Moon is going to be a major interference, but we could see a rate of about 20 per hour,” said Bill Cooke, head of NASA’s Meteoroid Environments Office at NASA’s Marshall Space Flight Center in Huntsville, Alabama. “Some models, including ours, indicate that particles may encounter Earth on November 16 at around 5:30 p.m. EST [2230 GMT], where we could see anywhere from 100 to 200 meteors per hour. So, we could get a Leonid outburst, but unfortunately it is not favorably placed for viewing from the United States.”

As our Earth passes through the dusty matter, it may encounter a place where the comet let loose with a large amount of its payload – or it may pass through an area where the “comet stuff” is thin. We might even pass through an area which produces an exciting “meteor storm” like the Leonids produced in 1883! For those in the know, the Leonid meteor shower also made a rather incredible appearance in 1866 and 1867 – dumping up to 1000 (not a typo, folks) shooting stars recorded even with a Moon present! It erupted again in 1966 and in 1998 and produced 3000 (yep. 3000!) video recorded meteors during the years of 2001 and 2002. But remember, human eyes may only be able to detect just a few. So what’s a realistic guess?

According to Cooke; “We could see rates of about five meteors per hour,” he explained. “If people want to see the Leonids, it might be good to watch the nights of November 16th and 17th. Instead of just going out one night, you might want to go out twice.”

Chart Courtesy of "Your Sky"

And to make this year’s show twice as nice, you’ll have a hard time not being distracted with the Moon and Mars being right on the radiant! You won’t be able to miss the Red Planet as the Moon slides along south… First to Mars’ west and then to the east on the nights of November 18th and 19th.

What a terrific show!