Weekend SkyWatcher’s Forecast: July 2-4, 2010

Greetings, fellow SkyWatchers! Hopefully the rains have passed in your area and you’re ready for some dark skies and a double-dip… Double stars that is! This weekend we’ll take a look at some of the most colorful and interesting binary stars of the summer. Need more? Then hang tight as we take a look at one of the most concentrated globular clusters aroumd! Whenever you’re ready, I’ll see you in the backyard…

July 2, 2010 – This date marks the 1820 passing of British optician Peter Dollond, inventor of the triple achromatic lens. Dollond’s improvements to the refracting telescope included placing convex lenses of crown glass on either side of a biconcave flint glass lens to make the achromatic triplet lens we know today!

Now turn binoculars or telescopes toward magnitude 2.7 Alpha Librae, the second brightest star in the celestial ‘‘Scales.’’ Its proper name is Zuben El Genubi, and, as Star Wars as that sounds, the ‘‘Southern Claw’’ is actually quite close to home at a distance of only 65 light-years. No matter what size optics you are using, you’ll easily see Alpha’s widely spaced 5th magnitude companion, which shares the same proper motion. Alpha itself is a spectroscopic binary, as was verified during an occultation event, and its inseparable companion is only a half-magnitude dimmer according to the light curves. Enjoy this easy pair tonight!

July 3, 2010 – Tonight let’s go deep south and have look at an area that once held something almost half a bright as tonight’s later Moon and over four times brighter than Venus. Only one thing could light up the skies like that—a supernova.

According to historical records from Europe, China, Egypt, Arabia, and Japan, 1,003 years ago the very first supernova event was noted. Appearing in the constellation of Lupus, it was at first believed to be a comet by the Egyptians, yet the Arabs saw it as an illuminating ‘‘star.’’


Located less than a finger-width northeast of Beta Lupi (RA 15 02 48 Dec –41 54 42) and half a degree east of Kappa Centaurus, no visible trace is left of a once-grand event that spanned 5 months of observation, beginning in May and lasting until it dropped below the horizon in September 1006. It is believed that most of the star was converted to energy, and very little mass remains. In the area, a 17th magnitude star that shows a tiny gas ring and radio source 1459-41 remains our best candidate for pinpointing this incredible event.

Why you’re at it, try a challenging double star—Upsilon Librae (RA 15 37 01 Dec –28 08 06). This beautiful red star is right at the limit for a small telescope, but quite worthy, as the pair is a widely disparate double. Look for the 11.5-magnitude companion to the south in a very nice field of stars!

July 4. 2010 – Tonight let’s have a look at 400-lightyear-distant Rasalgethi—Alpha Herculis (RA 17 14 38 Dec +14 23 25). Known as the ‘‘Head of the Kneeling One,’’ it’s an easily resolved double and is noted for its fine color contrast. At magnitude 3.5, the variable bright primary is one of the largest known stars, with a diameter four times the Earth–Sun distance. Rasalgethi’s photospheric temperature is so low (3,000 Kelvin) that it barely glows a warm reddish orange. Meanwhile, its 5.4-magnitude companion is a yellow giant with a temperature twice the primary. The two together make Rasalgethi A seem a deeper red, while Rasalgethi B takes on a lovely yellow-green hue.

Need some fireworks? Then check out a single small globular—M80 (RA 16 17 02 Dec –22 58 30). Located about 4 degrees northwest of Antares (about two finger-widths), this little globular cluster is a powerpunch. Located in a region heavily obscured by dark dust, M80 will shine like an unresolvable star to small binoculars, but reveal itself to be one of the most heavily concentrated globulars in the telescope. Discovered within days of each other by Messier and Mechain, respectively, in 1781, this intense Class I globular cluster is around 36,000 light-years distant.


In 1860, M80 became the first globular cluster that was known to host a nova. As stunned scientists watched, a centrally located star brightened to magnitude 7 over a period of days, becoming known as T Scorpii. The event then dimmed more rapidly than expected, making observers wonder exactly what they had seen. Since most globular clusters’ stars are all about the same age, the hypothesis was put forward that perhaps they had witnessed an actual collision of stellar members. Given that the cluster contains more than a million stars, the probability is that some 2,700 collisions of this type may have occurred during M80’s lifetime.

Have a super weekend!

This week’s awesome images are: Zuben El Genubi, Field of SN1006, Upsilon Librae, Rasalgethi and M80. All done by Palomar Observatory, courtesy of Caltech. We thank you so much!

Graphite ‘Whiskers’ Found in Apollo Moon Rocks

A. Light microscopy image of 72255,89. (B) Higher magnification image of transition from light to dark material in area shown in (A). (C) Raman spectra of three types of graphite analyzed in the sample. Credit: A. Steele, et al.

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Long-held secrets continue to be unlocked from the Moon. Researchers taking a new look at a rock brought back by the Apollo 17 mission have discovered graphite in the form of tiny whiskers within the lunar sample. Just like the recent finding of water on the Moon, it was previously thought that any carbon present in the Apollo rocks came from terrestrial contamination from the way the lunar samples were collected, processed or stored. Andrew Steele, who led a team from the Carnegie Institution’s Geophysical Laboratory said the graphite could have come from carbonaceous impactors that struck both the Moon and Earth during the Late Heavy Bombardment, approximately 4.1 to 3.8 billion years ago, and if so, could provide a new and important source of information about this period in the solar system’s early history.

“We were really surprised at the discovery of graphite and graphite whiskers,” Steele said. “We were not expecting to see anything like this.”

The tiny graphite whiskers or needles were found in multiple spots within a specific area of lunar sample 722255 from the Mare Serenitatis impact crater in the Taurus-Littrow region, indicating that the minerals are in fact from the Moon and not just contamination.

Steele told Universe Today that he and his team don’t think the graphite originated on the Moon, but haven’t ruled it out completely.

“Our initial thought is that it is from the impactor, as we find it in a very fine grained impact melt breccias,” he said in an email. “I am currently looking in more pristine lunar rocks, i.e. lavas that do not contain evidence of meteorite material, for carbon phases.”

He added that the graphite may have come from the impactor itself, or it may have formed from the condensation of carbon-rich gas released during the impact.

The team used Raman imaging spectroscopy (CRIS) on a thin section of a freshly fractured surface of the rock. This identifies minerals and carbon species and their spatial relationship to each other beneath the surface of a sample. Steele said even though this rock has been on Earth since 1972, new techniques and instruments allowed for the new discovery.

“The analytical spot size is smaller and so we can look at smaller phases,” he said. “The sensitivity is better in the newer instruments and we can use spatially resolved methods that are much more sensitive than in the Apollo era.”

Impact breccias are made up of a jumble of smaller fragments that formed when the moon was struck by an asteroid or other object.

Other previous spectroscopy of the Moon’s surface has also found trace amounts of carbon, but it was thought to have come from the solar wind. However, Steele said he and his team have also ruled that out as the source.

“Several lines of reasoning confirm that the observed graphite and graphite whiskers (GW) are indigenous to the sample,” said the team in their paper. “In particular, all known GW synthesis methods involve deposition from a carbon-containing gas at relatively high temperatures ranging from 1273 to ~3900 K. Thus, the GWs identified in 72255 cannot have been synthesized as a result of sample handling and preparation. Moreover, they could not have been implanted by solar wind, because this carbon is typically too small to identify structurally at the magnifications used. The crystalline graphite grains detected here are likely either intact remnants of graphite and GWs from the Serentatis impactor, or they could have formed from condensation of carbon-rich gas released during impact.”

Steele said their findings indicate that impacts may be another process by which GWs can form in our solar system. Additionally, it appears carbonaceous material from impacts at the time of the Late Heavy Bombardment (LHB), and at a time when life may have been emerging on Earth, does survive on the Moon.

“The Solar System was chaotic with countless colliding objects 3.8 billion years ago,” Steele said in a press release. “Volatiles—compounds like water and elements like carbon were vaporized under that heat and shock. These materials were critical to the creation of life on Earth.”

While the impacts to Earth during that period have since been erased, craters on the Moon are still pristine, so the Moon potentially holds a record of the meteoritic carbon input to the Earth-Moon system, when life was just beginning to emerge on Earth.

The research is published in the July 2, 2010, issue of Science.

New Dates for Final Shuttle Launches

Discovery on the launchpad in March, 2010 for the STS-131 mission. Credit: Nancy Atkinson

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If you are tentatively planning to attend one of the final shuttle launches, the uncertainty on launch dates just got a bit more certain; plus — an added benefit — we won’t see the end of the shuttle program until 2011.

NASA announced new target dates for the final two (and maybe three) shuttle missions. STS-133 is now aiming for November 1, 2010 at approximately 4:33 p.m. EDT for the final flight of shuttle Discovery, and for STS-134, February 26, 2011 at around 4:19 p.m. EST for shuttle Endeavour’s last launch. The potential bonus mission STS-135, would launch sometime in August 2011, if approved by Congress and NASA. The latest word on that was that NASA officials hope the decision would be made sometime this month.


The target dates were changed because the Alpha Magnetic Spectrometer instrument, heading for installation on the International Space Station won’t be ready by the time of the previously planned Sept. 16 launch for STS-133. With that launch moving to November, STS-134 cannot fly as planned, so the next available launch window — taking into account sun angles and other planned launches –is in February 2011.

These dates were rumored last week, but this is now the official word. However, of course, all target launch dates are subject to change.

The last external tanks for the STS-134 mission was recently completed at the Michoud Assembly Facility in New Orleans. There will be a final farewell ceremony at 9 a.m. CDT on Thursday, July 8, which will be shown on NASA TV. The event will commemorate 37 years of successful tank deliveries and the final external tank’s rollout for the last space shuttle flight. Coverage begins at 8:45 a.m.

The tank, designated ET-138, will travel on a wheeled transporter one mile to the Michoud barge dock. It will be accompanied by the Storyville Stompers, a traditional area brass band, and hundreds of handkerchief-waving employees in typical New Orleans fashion and spirit.

The tank will travel on a 900-mile sea journey to NASA’s Kennedy Space Center in Florida, where it will support shuttle Endeavour’s STS-134 launch. No word yet on how the oil spill may affect the journey.

Another tank that was damaged in Hurricane Katrina is being refurbished for the Launch-On-Need (LON) rescue mission STS-335, which if not needed and if it gets approval to fly as the actual final shuttle mission, (Atlantis) would change to STS-135.

Ken Kremer (who has written for Universe Today) has an article on SpaceRef about his tour of the Michoud Facility, which includes some great images.

Mysterious Giant Gas Ring Explained

he Leo ring: deep image in the optical domain with the distribution of the gas in HI in yellow-orange. The thumbnails on the right are a three of the dense areas of the ring with their optical counterparts. © CFHT/Astron - P.A. Duc

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From a Canada-France-Hawaii Telescope press release:

An international team unveiled the origin of the giant gas ring in the Leo group of galaxies. With the Canada-France-Hawaii Telescope, the scientists were able to detect an optical signature of the ring corresponding to star forming regions. This observation rules out the primordial nature of the gas, which is of galactic origin. Thanks to numerical simulations made at CEA, a scenario for the formation of this ring has been proposed: a violent collision between two galaxies, slightly more than one billion years ago. The results will be published in the Astrophysical Journal Letters.

In the current theories on galaxy formation, the accretion of cold primordial gas is a key-process in the early steps of galaxy growth. This primordial gas is characterized by two main features: it has never sojourned in any galaxy and it does not satisfy the conditions required to form stars. Is such an accretion process still ongoing in nearby galaxies? To answer the question, large sky surveys are undertaken attempting to detect the primordial gas.

The Leo ring, a giant ring of cold gas 650,000 light-years wide surrounding the galaxies of the Leo group, is one of the most dramatic and mysterious clouds of intergalactic gas. Since its discovery in the 80s, its origin and its nature were debated. Last year, studies of the metal abundances in the gas led to the belief that the ring was made of this famous primordial gas.

Thanks to the sensitivity of the Canada-France-Hawaii Telescope MegaCam camera, the international team observed for the first time the optical counterpart of the densest regions of the ring, in visible light instead of radio waves. Emitted by massive young stars, this light points to the fact that the ring gas is able to form stars.

A ring of gas and stars surrounding a galaxy immediately suggests another kind of ring: a so-called collisional ring, formed when two galaxies collide. Such a ring is seen in the famous Cartwheel galaxy. Would the Leo ring be a collisional ring too?

In order to secure this hypothesis, the team used numerical simulations (performed on supercomputers at CEA) to demonstrate that the ring was indeed the result of a giant collision between two galaxies more than 38 million light-years apart: at the time of the collision, the disk of gas of one of the galaxies is blown away and will eventually form a ring outside of the galaxy. The simulations allowed the identification of the two galaxies which collided: NGC 3384, one of the galaxies at the center of the Leo group, and M96, a massive spiral galaxy at the periphery of the group. They also gave the date of the collision: more than a billion years ago!

The gas in the Leo ring is definitely not primordial. The hunt for primordial gas is still open!

Where In The Universe #110

It’s time once again for another Where In The Universe Challenge. Test your visual knowledge of the cosmos by naming where in the Universe this image was taken and give yourself extra points if you can name the spacecraft/telescope responsible for this picture. Post your guesses in the comments section, and check back on later at this same post to find the answer. To make this challenge fun for everyone, please don’t include links or extensive explanations with your answer. Good luck!

UPDATE: The answer has now been posted below.

This is a composite image from the Chandra X-Ray Telescope of one of the many star-forming regions in W3, called W3 Main. The green and blue represent lower and higher-energy X-rays, respectively, while red shows optical emission. There are hundreds of X-ray sources here, and these bright point-like objects are an extensive population of several hundred young stars, many of which were not found in earlier infrared studies.

Find out more about this image at the Chandra website.

R Coronae Australis: A Cosmic Watercolor

The nearby star-forming region around the star R Coronae Australis imaged by the Wide Field Imager (WFI) on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile.

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From an ESO press release:

This magnificent view of the region around the star R Coronae Australis was created from images taken with the Wide Field Imager (WFI) at ESO’s La Silla Observatory in Chile. R Coronae Australis lies at the heart of a nearby star-forming region and is surrounded by a delicate bluish reflection nebula embedded in a huge dust cloud. The image reveals surprising new details in this dramatic area of sky.

The star R Coronae Australis lies in one of the nearest and most spectacular star-forming regions. This portrait was taken by the Wide Field Imager (WFI) on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile. The image is a combination of twelve separate pictures taken through red, green and blue filters.

This image shows a section of sky that spans roughly the width of the full Moon. This is equivalent to about four light-years at the distance of the nebula, which is located some 420 light-years away in the small constellation of Corona Australis (the Southern Crown). The complex is named after the star R Coronae Australis, which lies at the centre of the image. It is one of several stars in this region that belong to the class of very young stars that vary in brightness and are still surrounded by the clouds of gas and dust from which they formed.

The intense radiation given off by these hot young stars interacts with the gas surrounding them and is either reflected or re-emitted at a different wavelength. These complex processes, determined by the physics of the interstellar medium and the properties of the stars, are responsible for the magnificent colours of nebulae. The light blue nebulosity seen in this picture is mostly due to the reflection of starlight off small dust particles. The young stars in the R Coronae Australis complex are similar in mass to the Sun and do not emit enough ultraviolet light to ionise a substantial fraction of the surrounding hydrogen. This means that the cloud does not glow with the characteristic red colour seen in many star-forming regions.

The huge dust cloud in which the reflection nebula is embedded is here shown in impressively fine detail. The subtle colours and varied textures of the dust clouds make this image resemble an impressionist painting. A prominent dark lane crosses the image from the centre to the bottom left. Here the visible light emitted by the stars that are forming inside the cloud is completely absorbed by the dust. These objects could only be detected by observing at longer wavelengths, by using a camera that can detect infrared radiation.

R Coronae Australis itself is not visible to the unaided eye, but the tiny, tiara-shaped constellation in which it lies is easily spotted from dark sites due to its proximity on the sky to the larger constellation of Sagittarius and the rich star clouds towards the centre of our own galaxy, the Milky Way.

For more images and videos see this ESO webpage.

Red Bull Stratos Update: Breaking the Speed of Sound in Freefall

Baumgartner during a test flight. Credit: Red Bull Stratos

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Here’s an update on the Red Bull Stratos project, where skydiver Felix Baumgartner will attempt to break the speed of sound during freefall. (Read our preview article). Baumgartner and the project’s aeronautic’s experts recently conducted the latest round of high-altitude test jumps and step-off procedure tests. Baumgartner himself reports feeling both satisfaction and apprehension while the team prepares to move into a new phase of testing.

During the last week in May 2010, the Red Bull Stratos team conducted three important tests. In the capsule step-off test, conducted at Sage Cheshire Aerospace in Lancaster, California, the capsule dangled from a 40,000-ton crane to simulate its suspension from the balloon flight train, with Baumgartner practicing his movements inside, exiting and stepping off. The purpose was to determine how the vessel reacts to Baumgartner’s motion, and whether those reactions could compromise his descent. Even a relatively gentle tumble created by imprecise step-off could not only hinder Baumgartner’s ability to break the sound barrier but also suddenly devolve into a dangerously rapid “flat spin” once he encounters a level of increased air density.

Felix Baumgartner during a test flight. Credit: Red Bull Stratos

Next, a group of pre-eminent aerospace experts and test pilots – including Joe Kittinger, who holds the records Baumgartner will try to break – gathered in a deserted Palmdale fairground to witness something they’d never seen during all their combined years of experience: a bungee jump in a pressurized space suit and helmet. After multiple jumps from a crane basket suspended 200 feet above the ground, Baumgartner’s exit technique had evolved into something that one team member described as “perfect.”

The finale to the week of testing was a series of skydives over the desert in Perris, California, reaching approximately 26,000 feet. This test, conducted on May 27, 2010, was the first in a fully pressurized suit and was a follow-up to a similar day of flights in early spring. Baumgartner had been frustrated by the awkwardness of his equipment, especially by the way his chest pack – a vital technology hub for the descent – jammed his helmet and inhibited movement on descent and blocked his vision while landing. Objectives were to get a clean step-off from the rear-exit airplane; assess controllability and various body positions in the fully pressurized suit; experience suit deflation upon descent; and test a new chest pack system that allows one side to move out of Baumgartner’s line of sight so he can spot his landing. Baumgartner’s technique and the improved equipment worked so quite well, so the team was able to accomplish all objectives.

Source: Red Bull Stratos

Finding the Origin of Milky Way’s Ancient Stars

Simulation showing a Milky Way-like galaxy around five billion years ago, when most satellite galaxy collisions were happening. Credit: Andrew Cooper, John Helly (Durham University)

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From the Royal Astronomical Society

Many of the Milky Way’s ancient stars are remnants of other smaller galaxies torn apart by violent galactic collisions around five billion years ago, according to researchers at Durham University, who publish their results in a new paper in the journal Monthly Notices of the Royal Astronomical Society.

Scientists at Durham’s Institute for Computational Cosmology and their collaborators at the Max Planck Institute for Astrophysics, in Germany, and Groningen University, in Holland, ran huge computer simulations to recreate the beginnings of our Galaxy.

The simulations revealed that the ancient stars, found in a stellar halo of debris surrounding the Milky Way, had been ripped from smaller galaxies by the gravitational forces generated by colliding galaxies.

Cosmologists predict that the early Universe was full of small galaxies which led short and violent lives. These galaxies collided with each other leaving behind debris which eventually settled into more familiar looking galaxies like the Milky Way.

The researchers say their finding supports the theory that many of the Milky Way’s ancient stars had once belonged to other galaxies instead of being the earliest stars born inside the Galaxy when it began to form about 10 billion years ago.

Simulation showing the stellar halo of a Milky Way-like galaxy in the present day. Credit: Andrew Cooper (Durham University)

Lead author Andrew Cooper, from Durham University’s Institute for Computational Cosmology, said: “Effectively we became galactic archaeologists, hunting out the likely sites where ancient stars could be scattered around the galaxy.

“Our simulations show how different relics in the Galaxy today, like these ancient stars, are related to events in the distant past.

“Like ancient rock strata that reveal the history of Earth, the stellar halo preserves a record of a dramatic primeval period in the life of the Milky Way which ended long before the Sun was born.”

The computer simulations started from shortly after the Big Bang, around 13 billion years ago, and used the universal laws of physics to simulate the evolution of dark matter and the stars.

These simulations are the most realistic to date, capable of zooming into the very fine detail of the stellar halo structure, including star “streams” – which are stars being pulled from the smaller galaxies by the gravity of the dark matter.

One in one hundred stars in the Milky Way belong to the stellar halo, which is much larger than the Galaxy’s familiar spiral disk. These stars are almost as old as the Universe.

Professor Carlos Frenk, Director of Durham University’s Institute for Computational Cosmology, said: “The simulations are a blueprint for galaxy formation.

“They show that vital clues to the early, violent history of the Milky Way lie on our galactic doorstep.

“Our data will help observers decode the trials and tribulations of our Galaxy in a similar way to how archaeologists work out how ancient Romans lived from the artefacts they left behind.”

The research is part of the Aquarius Project, which uses the largest supercomputer simulations to study the formation of galaxies like the Milky Way and was partly funded by the UK’s Science and Technology Facilities Council (STFC).

Aquarius was carried out by the Virgo Consortium, involving scientists from the Max Planck Institute for Astrophysics in Germany, the Institute for Computational Cosmology at Durham University, UK, the University of Victoria in Canada, the University of Groningen in the Netherlands, Caltech in the USA and Trieste in Italy.

Durham’s cosmologists will present their work to the public as part of the Royal Society’s 350th anniversary ‘See Further’ exhibition, held at London’s Southbank Centre until July 4th.

Zapping Titan-Like Atmosphere with UV Creates Life Precursors

Which Planets Have Rings?
This colorized image taken by the Cassini orbiter, shows Saturn's A and F rings, the small moon Epimetheus and Titan, the planet's largest moon. Credit: NASA/JPL/Space Science Institute

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From the University of Arizona

The first experimental evidence showing how atmospheric nitrogen can be incorporated into organic macromolecules is being reported by a University of Arizona team. The finding indicates what organic molecules might be found on Titan, the moon of Saturn that scientists think is a model for the chemistry of pre-life Earth.

Earth and Titan are the only known planetary-sized bodies that have thick, predominantly nitrogen atmospheres, said Hiroshi Imanaka, who conducted the research while a member of UA’s chemistry and biochemistry department.

How complex organic molecules become nitrogenated in settings like early Earth or Titan’s atmosphere is a big mystery, Imanaka said.

“Titan is so interesting because its nitrogen-dominated atmosphere and organic chemistry might give us a clue to the origin of life on our Earth,” said Imanaka, now an assistant research scientist in the UA’s Lunar and Planetary Laboratory. “Nitrogen is an essential element of life.”

However, not just any nitrogen will do. Nitrogen gas must be converted to a more chemically active form of nitrogen that can drive the reactions that form the basis of biological systems.

Imanaka and Mark Smith converted a nitrogen-methane gas mixture similar to Titan’s atmosphere into a collection of nitrogen-containing organic molecules by irradiating the gas with high-energy UV rays. The laboratory set-up was designed to mimic how solar radiation affects Titan’s atmosphere.

Most of the nitrogen moved directly into solid compounds, rather than gaseous ones, said Smith, a UA professor and head of chemistry and biochemistry. Previous models predicted the nitrogen would move from gaseous compounds to solid ones in a lengthier stepwise process.

Titan looks orange in color because a smog of organic molecules envelops the planet. The particles in the smog will eventually settle down to the surface and may be exposed to conditions that could create life, said Imanaka, who is also a principal investigator at the SETI Institute in Mountain View, Calif.

However, scientists don’t know whether Titan’s smog particles contain nitrogen. If some of the particles are the same nitrogen-containing organic molecules the UA team created in the laboratory, conditions conducive to life are more likely, Smith said.

Laboratory observations such as these indicate what the next space missions should look for and what instruments should be developed to help in the search, Smith said.

Imanaka and Smith’s paper, “Formation of nitrogenated organic aerosols in the Titan upper atmosphere,” is scheduled for publication in the Early Online edition of the Proceedings of the National Academy of Sciences the week of June 28. NASA provided funding for the research.

The UA researchers wanted to simulate conditions in Titan’s thin upper atmosphere because results from the Cassini Mission indicated “extreme UV” radiation hitting the atmosphere created complex organic molecules.

Therefore, Imanaka and Smith used the Advanced Light Source at Lawrence Berkeley National Laboratory’s synchroton in Berkeley, Calif. to shoot high-energy UV light into a stainless steel cylinder containing nitrogen-and-methane gas held at very low pressure.

The researchers used a mass spectrometer to analyze the chemicals that resulted from the radiation.

Simple though it sounds, setting up the experimental equipment is complicated. The UV light itself must pass through a series of vacuum chambers on its way into the gas chamber.

Many researchers want to use the Advanced Light Source, so competition for time on the instrument is fierce. Imanaka and Smith were allocated one or two time slots per year, each of which was for eight hours a day for only five to 10 days.

For each time slot, Imanaka and Smith had to pack all the experimental equipment into a van, drive to Berkeley, set up the delicate equipment and launch into an intense series of experiments. They sometimes worked more than 48 hours straight to get the maximum out of their time on the Advanced Light Source. Completing all the necessary experiments took years.

It was nerve-racking, Imanaka said: “If we miss just one screw, it messes up our beam time.”

At the beginning, he only analyzed the gases from the cylinder. But he didn’t detect any nitrogen-containing organic compounds.

Imanaka and Smith thought there was something wrong in the experimental set-up, so they tweaked the system. But still no nitrogen.

“It was quite a mystery,” said Imanaka, the paper’s first author. “Where did the nitrogen go?”

Finally, the two researchers collected the bits of brown gunk that gathered on the cylinder wall and analyzed it with what Imanaka called “the most sophisticated mass spectrometer technique.”

Imanaka said, “Then I finally found the nitrogen!”

Imanaka and Smith suspect that such compounds are formed in Titan’s upper atmosphere and eventually fall to Titan’s surface. Once on the surface, they contribute to an environment that is conducive to the evolution of life.

Opportunity Rover Able to See More Detail of Endeavour Crater

Since the summer of 2008, when NASA's Mars Exploration Rover Opportunity finished two years of studying Victoria Crater, the rover's long-term destination has been the much larger Endeavour Crater to the southeast. Credit: JPL

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From a JPL press release:

Mars rover team members have begun informally naming features around the rim of Endeavour Crater, as they develop plans to investigate that destination when NASA’s Opportunity rover arrives there after many more months of driving. A new, super-resolution view of a portion of Endeavour’s rim reveals details that were not discernible in earlier images from the rover. Several high points along the rim can be correlated with points discernible from orbit.

Super-resolution is an imaging technique combining information from multiple pictures of the same target to generate an image with a higher resolution than any of the individual images.

Endeavour has been the team’s long-term destination for Opportunity since the summer of 2008, when the rover finished two years of studying Victoria Crater. By the spring of 2010, Opportunity had covered more than a third of the charted, 19-kilometer (12-mile) route from Victoria to Endeavour and reached an area with a gradual, southward slope offering a view of Endeavour’s elevated rim.

After the rover team chose Endeavour as a long-term destination, the goal became even more alluring when observations with the Compact Reconnaissance Imaging Spectrometer for Mars, on NASA’s Mars Reconnaissance Orbiter, found clay minerals exposed at Endeavour. Clay minerals, which form under wet conditions, have been found extensively on Mars from orbit, but have not been examined on the surface. Additional observations with that spectrometer are helping the rover team choose which part of Endeavour’s rim to visit first with Opportunity.

The team is using the theme of names of places visited by British Royal Navy Capt. James Cook in his 1769-1771 Pacific voyage in command of H.M.S. Endeavour for informal names of sites at Endeavour Crater. Points visible in the super-resolution view from May 12 include “Cape Tribulation” and “Cape Dromedary.”

See more images and info on the names of the different features at Stu Atkinson’s “Road to Endeavour” blog.