Posted on by Fraser Cain

Young Universe Was Surprisingly Structured

Combining observations with ESO’s Very Large Telescope and ESA’s XMM-Newton X-ray observatory, astronomers have discovered the most distant, very massive structure in the Universe known so far.

It is a remote cluster of galaxies that is found to weigh as much as several thousand galaxies like our own Milky Way and is located no less than 9,000 million light-years away.

The VLT images reveal that it contains reddish and elliptical, i.e. old, galaxies. Interestingly, the cluster itself appears to be in a very advanced state of development. It must therefore have formed when the Universe was less than one third of its present age.

The discovery of such a complex and mature structure so early in the history of the Universe is highly surprising. Indeed, until recently it would even have been deemed impossible.

Serendipitous discovery
Clusters of galaxies are gigantic structures containing hundreds to thousands of galaxies. They are the fundamental building blocks of the Universe and their study thus provides unique information about the underlying architecture of the Universe as a whole.

About one-fifth of the optically invisible mass of a cluster is in the form of a diffuse, very hot gas with a temperature of several tens of millions of degrees. This gas emits powerful X-ray radiation and clusters of galaxies are therefore best discovered by means of X-ray satellites (cf. ESO PR 18/03 and 15/04).

It is for this reason that a team of astronomers [1] has initiated a search for distant, X-ray luminous clusters “lying dormant” in archive data from ESA’s XMM-Newton satellite observatory.

Studying XMM-Newton observations targeted at the nearby active galaxy NGC 7314, the astronomers found evidence of a galaxy cluster in the background, far out in space. This source, now named XMMU J2235.3-2557, appeared extended and very faint: no more than 280 X-ray photons were detected over the entire 12 hour-long observations.

A Mature Cluster at Redshift 1.4
Knowing where to look, the astronomers then used the European Southern Observatory’s Very Large Telescope (VLT) at Paranal (Chile) to obtain images in the visible wavelength region. They confirmed the nature of this cluster and it was possible to identify 12 comparatively bright member galaxies on the images (see ESO PR Photo 05b/05).

The galaxies appear reddish and are of the elliptical type. They are full of old, red stars. All of this indicates that these galaxies are already several thousand million years old. Moreover, the cluster itself has a largely spherical shape, also a sign that it is already a very mature structure.

In order to determine the distance of the cluster – and hence its age – Christopher Mullis, former European Southern Observatory post-doctoral fellow and now at the University of Michigan in the USA, and his colleagues used again the VLT, now in the spectroscopic mode. By means of one of the FORS multi-mode instruments, the astronomers zoomed-in on the individual galaxies in the field, taking spectral measurements that reveal their overall characteristics, in particular their redshift and hence, distance [2].

The FORS instruments are among the most efficient and versatile available anywhere for this delicate work, obtaining on the average quite detailed spectra of 30 or more galaxies at a time.

The VLT data measured the redshift of this cluster as 1.4, indicating a distance of 9,000 million light-years, 500 million light years farther out than the previous record holding cluster.

This means that the present cluster must have formed when the Universe was less than one third of its present age. The Universe is now believed to be 13,700 million years old.

“We are quite surprised to see that a fully-fledged structure like this could exist at such an early epoch,” says Christopher Mullis. “We see an entire network of stars and galaxies in place, just a few thousand million years after the Big Bang”.

“We seem to have underestimated how quickly the early Universe matured into its present-day state,” adds Piero Rosati of ESO, another member of the team. “The Universe did grow up fast!”

Towards a Larger Sample
This discovery was relative easy to make, once the space-based XMM and the ground-based VLT observations were combined. As an impressive result of the present pilot programme that is specifically focused on the identification of very distant galaxy clusters, it makes the astronomers very optimistic about their future searches. The team is now carrying out detailed follow-up observations both from ground- and space-based observatories. They hope to find many more exceedingly distant clusters, which would then allow them to test competing theories of the formation and evolution of such large structures.

“This discovery encourages us to search for additional distant clusters by means of this very efficient technique,” says Axel Schwope, team leader at the Astrophysical Institute Potsdam (Germany) and responsible for the source detection from the XMM-Newton archival data. Hans B?hringer of the Max Planck Institute for Extraterrestrial Physics (MPE) in Garching, another member of the team, adds: “Our result also confirms the great promise inherent in other facilities to come, such as APEX (Atacama Pathfinder Experiment) at Chajnantor, the site of the future Atacama Large Millimeter Array. These intense searches will ultimately place strong constraints on some of the most fundamental properties of the Universe.”

Notes
[1]: The team is composed of Chris Mullis (University of Michigan, USA), Piero Rosati (ESO Garching, Germany), Georg Lamer and Axel Schwope (Astrophysical Institute, Postdam, Germany), Hans B?hringer, Rene Fassbender, and Peter Schuecker (Max-Planck Institute for Extra-terrestrial Physics, Garching, Germany).

[2]: In astronomy, the “redshift” denotes the fraction by which the lines in the spectrum of an object are shifted towards longer wavelengths. Since the redshift of a cosmological object increases with distance, the observed redshift of a remote galaxy also provides an estimate of its distance.

Original Source: ESO News Release

Posted on by Fraser Cain

Spitzer Finds Hidden Galaxies

How do you hide something as big and bright as a galaxy? You smother it in cosmic dust. NASA’s Spitzer Space Telescope saw through such dust to uncover a hidden population of monstrously bright galaxies approximately 11 billion light-years away.

These strange galaxies are among the most luminous in the universe, shining with the equivalent light of 10 trillion suns. But, they are so far away and so drenched in dust, it took Spitzer’s highly sensitive infrared eyes to find them.

“We are seeing galaxies that are essentially invisible,” said Dr. Dan Weedman of Cornell University, Ithaca, N.Y., co-author of the study detailing the discovery, published in today’s issue of the Astrophysical Journal Letters. “Past infrared missions hinted at the presence of similarly dusty galaxies over 20 years ago, but those galaxies were closer. We had to wait for Spitzer to peer far enough into the distant universe to find these.”

Where is all this dust coming from? The answer is not quite clear. Dust is churned out by stars, but it is not known how the dust wound up sprinkled all around the galaxies. Another mystery is the exceptional brightness of the galaxies. Astronomers speculate that a new breed of unusually dusty quasars, the most luminous objects in the universe, may be lurking inside. Quasars are like giant light bulbs at the centers of galaxies, powered by huge black holes.

Astronomers would also like to determine whether dusty, bright galaxies like these eventually evolved into fainter, less murky ones like our own Milky Way. “It’s possible stars like our Sun grew up in dustier, brighter neighborhoods, but we really don’t know. By studying these galaxies, we’ll get a better idea of our own galaxy’s history,” said Cornell’s Dr. James Houck, lead author of the study.

The Cornell-led team first scanned a portion of the night sky for signs of invisible galaxies using an instrument on Spitzer called the multiband imaging photometer. The team then compared the thousands of galaxies seen in this infrared data to the deepest available ground-based optical images of the same region, obtained by the National Optical Astronomy Observatory Deep Wide-Field Survey. This led to identification of 31 galaxies that can be seen only by Spitzer. “This large area took us many months to survey from the ground,” said Dr. Buell Jannuzi, co-principal investigator for the Deep Wide-Field Survey, “so the dusty galaxies Spitzer found truly are needles in a cosmic haystack.”

Further observations using Spitzer’s infrared spectrograph revealed the presence of silicate dust in 17 of these 31 galaxies. Silicate dust grains are planetary building blocks like sand, only smaller. This is the furthest back in time that silicate dust has been detected around a galaxy. “Finding silicate dust at this very early epoch is important for understanding when planetary systems like our own arose in the evolution of galaxies,” said Dr. Thomas Soifer, study co-author, director of the Spitzer Science Center, Pasadena, Calif., and professor of physics at the California Institute of Technology, also in Pasadena.

This silicate dust also helped astronomers determine how far away the galaxies are from Earth. “We can break apart the light from a distant galaxy using a spectrograph, but only if we see a recognizable signature from a mineral like silicate, can we figure out the distance to that galaxy,” Soifer said.

In this case, the galaxies were dated back to a time when the universe was only three billion years old, less than one-quarter of its present age of 13.5 billion years. Galaxies similar to these in dustiness, but much closer to Earth, were first hinted at in 1983 via observations made by the joint NASA-European Infrared Astronomical Satellite. Later, the European Space Agency’s Infrared Space Observatory faintly recorded comparable, nearby objects. It took Spitzer’s improved sensitivity, 100 times greater than past missions, to finally seek out the dusty galaxies at great distances.

The National Optical Astronomy Observatory Deep Wide-Field Survey used the National Science Foundation’s 4-meter (13-foot) telescope at Kitt Peak National Observatory, located southwest of Tucson, Ariz.

NASA’s Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA’s Science Mission Directorate, Washington, D.C. Science operations are conducted at the Spitzer Science Center. JPL is a division of Caltech. The infrared spectrograph was built by Ball Aerospace Corporation, Boulder, Colo., and Cornell; its development was led by Houck. The multiband imaging photometer was built by Ball Aerospace Corporation, the University of Arizona, Tucson, Ariz., and Boeing North American, Canoga Park, Calif.; its development was led by Dr. George Rieke of the University of Arizona.

The Infrared Astronomical Satellite was a joint effort between NASA, the Science and Engineering Research Council, United Kingdom and the Netherlands Agency for Aerospace Programmes, the Netherlands.

Artist’s conceptions, images and additional information about the Spitzer Space Telescope are available at http://www.spitzer.caltech.edu.

Original Source: Spitzer News Release

Posted on by Fraser Cain

Jupiter’s Auroras Helped by Io

Scientists have obtained new insight into the unique power source for many of Jupiter’s auroras, the most spectacular and active auroras in the Solar System. Extended monitoring of the giant planet with NASA’s Chandra X-ray Observatory detected the presence of highly charged particles crashing into the atmosphere above its poles.

X-ray spectra measured by Chandra showed that the auroral activity was produced by ions of oxygen and other elements that were stripped of most of their electrons. This implies that these particles were accelerated to high energies in a multimillion-volt environment above the planet’s poles. The presence of these energetic ions indicates that the cause of many of Jupiter’s auroras is different from auroras produced on Earth or Saturn.

“Spacecraft have not explored the region above the poles of Jupiter, so X-ray observations provide one of the few ways to probe that environment,” said Ron Elsner of the NASA Marshall Space Center in Huntsville, Alabama, and lead author on a recently published paper describing these results in the Journal for Geophysical Research. “These results will help scientists to understand the mechanism for the power output from Jupiter’s auroras, which are a thousand times more powerful than those on Earth.”

Electric voltages of about 10 million volts, and currents of 10 million amps – a hundred times greater than the most powerful lightning bolts – are required to explain the X-ray observations. These voltages would also explain the radio emission from energetic electrons observed near Jupiter by the Ulysses spacecraft.

On Earth, auroras are triggered by solar storms of energetic particles, which disturb Earth’s magnetic field. Gusts of particles from the Sun can also produce auroras on Jupiter, but unlike Earth, Jupiter has another way of producing auroras. Jupiter’s rapid rotation, intense magnetic field, and an abundant source of particles from its volcanically active moon, Io, create a huge reservoir of electrons and ions. These charged particles, trapped in Jupiter’s magnetic field, are continually accelerated down into the atmosphere above the polar regions where they collide with gases to produce the aurora, which are almost always active on Jupiter.

If the particles responsible for the aurora came from the Sun, they should have been accompanied by large number of protons, which would have produced an intense ultraviolet aurora. Hubble ultraviolet observations made during the Chandra monitoring period showed relatively weak ultraviolet flaring. The combined Chandra and Hubble data indicate that this auroral activity was caused by the acceleration of charged ions of oxygen and other elements trapped in the polar magnetic field high above Jupiter’s atmosphere.

Chandra observed Jupiter in February 2003 for four rotations of the planet (approximately 40 hours) during intense auroral activity. These Chandra observations, taken with its Advanced CCD Imaging Spectrometer, were accompanied by one-and-a-half hours of Hubble Space Telescope observations at ultraviolet wavelengths.

The research team also included Noe Lugaz, Hunter Waite, and Tariq Majeed (University of Michigan, Ann Arbor), Thomas Cravens (University of Kansas, Lawrence), Randy Gladstone (Southwest Research Institute, San Antonio, Texas), Peter Ford (Massachusetts Institute of Technology, Cambridge), Denis Grodent (University of Liege, Belgium), Anil Bhardwaj (Marshall Space Flight Center) and Robert MacDowell and Michael Desch (Goddard Space Flight Center, Greenbelt, Md.)

NASA’s Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for NASA’s Office of Space Science, Washington. Northrop Grumman of Redondo Beach, Calif., formerly TRW, Inc., was the prime development contractor for the observatory. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass.

Additional information and images are available at: http://chandra.harvard.edu and http://chandra.nasa.gov

Original Source: Chandra News Release

Posted on by Fraser Cain

Are We Alone?

Image Credit: “Seeking” ?1998
Lynette Cook. Used with Permission.
“All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.”
– German philosopher Arthur Schopenhauer (1788 – 1860)

Are we alone? Given the immensity of the Cosmos, a mathematical impossibility. Will we ever come to know we are not alone? That’s a tougher question. But should first contact occur today we could be in for a shock1. So right now may be a good time to prepare. And perhaps the best way to prepare is to imagine the possibility…

Numerous psychological studies have shown that “imagining a thing” makes us more receptive to the possibility. In fact many of the great breakthroughs in scientific thought came about as a result of the proper use of the creative imagination. Sir Isaac Newton saw the motions of all moons and planets everywhere in the simple fall of a ripe apple from the boughs of a tree. Albert Einstein perceived the relativity of all time and space while contemplating the accelerated motion of a trolley car moving away from the face of a public clocktower. We human beings might want to take a few moments and think about how we will respond should ET make an appearence in our small corner of the cosmos.

So, take a moment and relax. (Yes it’s true, deep breathing does help!) Imagine a universe populated with many and diverse forms of intelligent life. Extend yourself through time and space toward distant systems of suns and planets. See simple organisms thrilling to the rhythms of light and matter working in harmony to develop ever more sophisticated life-forms. Follow the earliest interstellar craft as they move tirelessly from system to system toward some distant beckoning beacon of promise. Surf beams of radiant energy flung like arrows from far away lighthouses upon the Ocean of Space.

Someday such imaginings may be confirmed by rock solid science – perhaps SETI will detect an indisputable signal from beyond, or “Michael Rennie” emerges as an emissary from the Galactic Federation of Planetary Systems trailed by Gort – the Wonder Robot.

Given the likelihood that such space-faring or highly communicative intelligences exist, and given all the billions of years for off-world intelligence to develop the means to travel and communicate, plus our own recent efforts to find them out, why don’t we know already?

One, and possibly the very best answer is “We aren’t ready.”

The human imagination also has its down-side: Imagine the initial shock and ridicule as we humans attempt to upright a world overturned by what for many will be an impossible event. Consider also how governments and institutions, groups and individuals, have responded to similar reports in the past. Remember “Mars-rock”? Do we hear much of it now? And what about pilot Hap Arnold’s “flying saucer” report. Can we really say that we have taken clear-headed, scientific looks at such things? Or is our normal response one of incredulity and ridicule? Hmmmm…

To know is to see truth wherever it may be found. No, we’re not saying that UFO’s have visited the Earth. What we are saying is that our response to those who make such claims is often one of ridicule and disrespect. Is it not possible that compassion and open-mindedness would be more appropriate?

So let’s seek truth where it can be found – right here on Earth. We can start by looking for unsuspected signs of intelligence around us2. Let’s take a clear-eyed look at our animal friends by setting aside prejudices concerning their intelligence. Those goldfish in the aquarium can be surprisingly sensitive about things. Walk near the tank during the day and they ignore you. Come feeding time, and you are the most interesting thing in the world to them.

To be sure we are very unlikely to learn that the universe is suffused with intelligence until we get past our own anthrocentrism. It took a lot of hard work (and self-sacrifice) by Copernicus, Kepler, and Galileo just to get western society to finally step “up to the edge” and see that the Blue Planet is most definitely not flat nor does it act as the axis around which all things celestial swing.

And even with the signs of intelligence abounding on our homeworld today we persist in thinking that all creatures exist for us, our amusement, our purposes. Under such conditions can we possibly appreciate how truly intelligent they are? And to be more germane, do we really think ET might want to come out and play with us under such circumstances?

Today we don’t seem to be ready to accept anything other than the myth of being alone. Yes, one way to tell this does have to do with how we relate to other creatures on the Blue Planet, but there are other reasons to doubt our readiness as well. Consider our political institutions; Why is it that our leaders and their associates spend so much time “down-playing” the truth of things, presenting specious arguments to motivate behavior, or putting controversial issues into the spin cycle? Is it because of hidden political or economic agendas? Or possibly because they don’t believe we can handle reality3?

Meanwhile high overhead, ET approaches the Earth – third stone from the Sun – and initiates a scan of the EM spectrum. Newscasts portray crisis after crisis, violence, conflict, bloodshed, environmental degradation. How would you – an intelligent being from elsewhere respond?

Personally, I’d activate the cloaking device.

ET is no dummy – he/she/it is after all an intelligent life-form possessed of advanced technology. One scan of Earth’s broadcast media and ET soon comes to see that this is not a place to be trifled with: The natives are restless. Emotion overrules reason. Reaction upstages proaction. Nations practice deception and ill-will in relationships – internal and external. Angry voices shout each other down – not just on the streets but in the houses of governance as well. We are not a happy bunch.

And yet the future remains always a bright star of possibility. Hope springs eternal in ET’s breast (or left antibular thorax as the case may be…)

ET of course, has seen such things before. Countless worlds of lesser and greater advancement have been encountered. Before ET learned the wisdom of keeping a safe distance, he-she-it actually tried to help a few troubled worlds such as our own. In the end ET may have had to overcome shock, ignorance, even bloody insurgencies. Costs were great, rewards few. Now ET waits – waits for us to pass certain tests – tests defined in some intragalactic protocol: “The Prime Directive”.

So the hailing frequencies are locked down. ET goes stealth. “Subspace” signals are transmitted to ET Central: “Earthlings are still at it. Planet approaching ecological crisis. Species dying off. The few have much, many have little. Schedule re-visit next solar maximum. Report over and out.”

Today our instruments can peer back to the very threshold of the Big Bang – nearly 13.7 million lightyears distant in time and space, millions and millions of galaxies, billions and billions of Suns. Who knows how many planets – many equal to or superior to our own in fecundity and arability. Some populated as yet only by single-cell organisms. Others by beings possessed of no organic form whatsoever. It doesn’t even take the imagination to see the possibility anymore. Those of us interested in astronomy also read and watch science fiction. All the heavy lifting has been done for us. Fantastic lifeforms dwell in fabulous environs undergoing incredible adventures: Star Trek, Star Wars, Babylon Five – you name it – we’ve seen it. And yes, many of us believe in our hearts – but even so, we want to know.

Even now we scan the heavens seeking proof. The SETI project is bringing its array of parallel narrow-band scanning recievers on line. We hope against hope that some not-too-circumspect intelligence is out there broadcasting narrowband signals intentionally (or not) seeking to conclusively demonstrate their presence in our universe.

Will SETI find them out? And if so, how will we respond to the reality?

It is possible to uncover intelligence in this way, but intelligent life-forms not only learn from experience but in advance of experience as well. Do we here on Earth choose to project our presence intentionally into the interstellar medium4?

No – that particular notion has already been discarded and perhaps wisely so. We know what we are like – others could be worse!

Psychology plays a big role in choices made by intelligent creatures. When they don’t trust others, they “down-play” the truth or offer specious arguments. When they make mistakes, they put things in the “spin cycle”. When they see other intelligences doing these kinds of things with great regularity they know that contact is to be avoided. Perhaps this is at essence in first contact protocol. Until truth is welcomed – even at the expense of notions held dear – a world is not ready. Otherwise the cost of engagement is too high, benefits too low, and outcomes too unpredictable – or worse – dangerous.

But we may detect extraterrestial intelligence in other ways. It’s a solid assumption that all advancing technologies pass through a broadband em broadcast phase. During such an era civilizations “leak” evidence of their existence. Unfortunately, even our largest radio telescope would be hard pressed to detect broadband transmissions – such as Earth’s – from as close as the Alpha Centauri system. Meanwhile the window on em broadcast may even be closing here on earth. How many of us watch television programs delivered by antenna today? Less than a half-century ago every house had its own “rabbit ears”. One-hundred years from now we may be EM mute…

We might also intercept a signal in transit between two worlds. Such an event would be serendipitous – luck would play a huge role. First we would have to be more or less line of sight. Why? Because the tighter such a signal is foused the further it travels without attenuation. Although laser (and maser) transmissions do diffract over great distances, we would still need to be well-placed to pick one up. Meanwhile such signals may not necessarily be narrow band in frequency. Why? Because phase-modulated transmission may be the most efficient way to transmit pictures, sounds, and data across space5.

Despite all these barriers to revelation what practical steps can we now take to prepare for some future “first contact”?

Assisted by writers of science fiction and purveyors of motion pictures, we’ve already made a start by imagining the possibility. Animal behaviorists have helped prepare us by investigating various types and degrees of intelligence in the natural world. Psychologists and socioligists have done the same thing in the realms of our own species.

Meanwhile on an individual basis we can all learn to pay more attention to intelligence as seen within our families, among friends, associates – and even strangers. (Perhaps especially strangers.) All this makes us more aware of what intelligence is and how it is communicated.

On the broadest possible levels we must all further our ability to welcome and speak truth – despite any pain it may leave in its wake.

Having done our own personal work, “homeworld work” can go forward. Collectively we can work together to expunge the seeds and uproot the weeds of war on the planet. Although this means holstering our weapons, it also means overcoming a persistent propensity toward propaganda, religious strife, scientific contention, and undue corporate economic advantage.

And of great importance at this time is the need to be more supportive of other homeworld species – irrespective of intelligence. Ecology teaches us that every creature plays an important role in Earth’s biosphere. Perhaps it should become a matter of human education, demographical planning, economics, and political activity to ensure that this particular insight truly guides our choices and behavior. After all so long as we remain exploitative of lesser species no truly intelligent extraterrerestial species is likely to have much to do with us. Scarier still, if there are any “bad boys” out there, they could easily rationalize “taking over the joint”.

So let’s say we clean up our act. What happens next?

Isn’t that enough? To live in a world where truth multiplies, nature is respected, intelligence is recognized, and peace reigns supreme is actually quite appealing in itself – for most intelligences worthy of interstellar relations.

But this article is not about social transformation per se – it’s about the very real possibility of first contact – something that could transpire even before our children take a leading role in the unfolding story of human history.

Are we ready to get ready?

If intelligence can germinate here, it can flower elsewhere. Why, of course, it’s all so – “self-evident!”

1 The 1997 hit movie “Contact” (based on a novel by Carl Sagan) portrayed the many and varied ways in which human beings responded to scientific proof of the existence of advanced extraterrestrial intelligence.

2 According to a BBC News article a captive African grey parrot named N’kisi has a vocabulary of almost one thousand words, shows evidence of a sense of humour, and devises new words and concocts phrases as needed.

3 Irrespective of its overall merits, US efforts to topple an Iraqi dictatorship were found to be based on overstated evidence. (See Conclusions of Senate’s Iraq report) Such misuses of information often occur when a government is unable to speak plainly to its citizens concerning matters of importance.

4 In an article published by the title Quantum Communication Between the Stars? SETI Institute member Seth Shostak recalls the heated response of England’s Astronomer Royal to the ad hoc messaging of M13 during a 1974 ceremonial at the Arecibo radio telescope in Puerto Rico.

5 The narrower the frequency used to transmit data through space the higher the signal-to-noise ratio. The most efficient mode of such transmission is to digitally switch a carrier frequency “on and off”. Such serial modes of transmission however, are very slow at transfering large amounts of data through space in short amounts of time. Such signals are however very useful for saying things like “look at me I am here!”.

About The Author: Inspired by the early 1900’s masterpiece: “The Sky Through Three, Four, and Five Inch Telescopes”, Jeff Barbour got a start in astronomy and space science at the age of seven. Currently Jeff devotes much of his time observing the heavens and maintaining the website Astro.Geekjoy.

Posted on by Fraser Cain

Sea Launch Delivers XM-3 to Orbit

Sea Launch Company today successfully delivered XM Satellite Radio’s XM-3 satellite to orbit from its ocean-based platform on the Equator, in its first mission of the 2005 manifest. Early data indicate the spacecraft is in excellent condition.

The Sea Launch Zenit-3SL rocket lifted off at 7:51 pm PST ( 03:51 GMT , Mar. 1), precisely on schedule, from the Odyssey Launch Platform, positioned at 154 degrees West Longitude. All systems performed nominally throughout the flight. The Block DM-SL upper stage inserted the 4,703 kg (10,346 lb) XM-3 satellite into an optimized geosynchronous transfer orbit of 2468 km x 35786 km, on its way to an orbital location for routine testing prior to placement in its final orbital position at 85 degrees West Longitude. A ground station in South Africa acquired the spacecraft’s first signal an hour after liftoff, as planned.

Built by Boeing Satellite Systems, International, Inc., the XM-3 satellite is a 702 model spacecraft, one of the most powerful satellites built today, designed to provide 18 kilowatts of total power at beginning of life. Like its sister spacecraft, XM-1 and XM-2 ? also launched by Sea Launch – XM-3 will transmit more than 150 channels of digital-quality music, news, sports, talk, comedy and children’s programming to subscribers across the continental United States.

Immediately following the mission, Jim Maser, president and general manager of Sea Launch, said, “I want to congratulate Boeing Satellite Systems and XM Satellite Radio on today’s successful mission. We are extremely proud to be able to provide another launch for both XM and Boeing and we look forward to continuing our long and mutually beneficial relationships. I also want to congratulate the entire Sea Launch team and thank each individual for their enormous contribution to today’s mission.?

Sea Launch Company, LLC, headquartered in Long Beach, Calif., and marketed through Boeing Launch Services (www.boeing.com/launch), is the world’s most reliable heavy-lift commercial launch service. This international partnership offers the most direct and cost-effective route to geostationary orbit. With the advantage of a launch site on the Equator, the reliable Zenit-3SL rocket can lift a heavier spacecraft mass or provide longer life on orbit, offering best value plus schedule assurance. For additional information and images of this successfully completed mission, visit the Sea Launch website at: www.sea-launch.com

Original Source: Sea Launch News Release

Posted on by Fraser Cain

Supply Ship Blasts Off With Special Camera

Carrying more than two tons of supplies, a Russian cargo spacecraft began a two-day trip to the International Space Station today after its launch from the Baikonur Cosmodrome in Kazakhstan. The ISS Progress 17 resupply ship launched at 1:09 p.m. CST. Less than 10 minutes later, it settled into orbit and automatic commands deployed its solar arrays and navigational antennas.

As the Progress launched, Expedition 10 Commander and NASA Station Science Officer Leroy Chiao and Flight Engineer Salizhan Sharipov were wrapping up their work day. The Station was flying over the southern Atlantic Ocean west of Cape Town, South Africa at an altitude of 225 statute miles at the time of liftoff.

Engine firings are scheduled later today and tomorrow to raise and refine the Progress’ orbit and its path to the Station for an automated docking at the aft port of the Zvezda Service Module on Wednesday at 2:15 p.m. CST. NASA TV will provide live coverage of the linkup beginning at 1:30 p.m. CST.

The Progress is carrying more than 2 tons of food, fuel, oxygen, water, spare parts and personal items for the crew. It is filled with 386 pounds of propellant, 242 pounds of oxygen and air, 1071 pounds of water, and more than 2932 pounds of spare parts, life support system components and experiment hardware. The manifest also includes an additional six-month supply of food in 86 containers to replenish the Station pantry. Among the items being carried on the Progress is a new heat exchanger device to replace a faulty component in the U.S. airlock that is needed for the resumption of spacewalks in U.S. space suits this summer.

Also in the Progress are cameras and lenses that will be used by the Expedition 11 crew to capture digital images of the thermal protection system on the Shuttle Discovery during its approach to the Station for docking during the STS-114 mission in May. The photos will be part of the imagery-gathering effort for Return to Flight to insure that the Shuttle has incurred no threatening damage to its tiles or the reinforced carbon-carbon coating on its wings during ascent.

Chiao and Sharipov are scheduled to open the hatch to the Progress a few hours after docking Wednesday to begin unloading its contents.

The Progress spacecraft that had been at the Station since Christmas night was undocked yesterday at 10:06 a.m. CST as the two vehicles flew over eastern Asia. Filled with discarded items, the ship fired its engines after undocking to move to a safe distance away from the Station for 10 days of engineering tests by Russian flight controllers. It will be deorbited on March 9 and will burn up in Earth?s atmosphere.

Original Source: NASA News Release

Posted on by Fraser Cain

What’s Up This Week – Feb 27 – Mar 6, 2005

Image credit: NOAO/AURA/NSF
Monday, February 28 – Let’s start tonight enjoying the early dark skies and go to our maps west of the M36 and M38 to identify AE Aurigae. As an unusual variable, AE is normally around 6th magnitude and resides approximately 1600 light years distant. The beauty in this region is not particularly the star itself but a faint nebula in which it resides known as IC 405, an area of mostly dust and very little gas. What makes this view so entertaining is that we are looking at a “runaway” star. It is believed that AE once originated from the M42 region in Orion. Cruising along at a very respectable speed of 80 miles per second, AE flew the “stellar nest” some 2.7 million years ago! Although the IC 405 is not directly related to AE, there is evidence within the nebula that areas have been cleared of their dust by the rapid northward motion of the star. AE’s hot, blue illumination and high energy photons fuel what little gas is contained within the region as well as reflects off the surrounding dust. Although we cannot “see” with our eyes like a photograph, together the pair form an outstanding view for the small backyard telescope and it is known as “The Flaming Star.”

Tuesday, March 1 – George Abell was born on this day in 1927. Abell was the man responsible for cataloging 2712 clusters of galaxies done with the Palomar sky survey completed in 1958. Using these plates, Abell put forth the idea that the grouping of such clusters distinguished the arrangement of matter in the universe. He developed the “luminosity function”, which shows relationship with brightness and number of members in each cluster, giving rise to distances. Abell also discovered a number of planetary nebulae and developed the theory (along with Peter Goldreich) of their evolution from red giants. Mr. Abell was a fascinating lecturer and a developer in many television series dedicated to explaining science and astronomy in a fun and easy to understand format. Abell was also a president and member of the Board of Directors for the Astronomical Society of the Pacific, as well as serving on the American Astronomical Society, Cosmology Commission of the International Astronomical Union, and accepted editorship of the Astronomical Journal just before he died.

Would you like to study an Abell galaxy cluster? Then let me sweep you away to Abell 426 just two degrees east of previous study star – Algol. I caution you that this is not an area that can be seen with the average telescope, but for those of you with very large aperture you will find a study region incredibly worth your time and attention. The brightest of this group of galaxies in the NGC 1275 at magnitude 12.7. As an incredible radio source, the NGC 1275 is thought to be two galaxies actually in the process of passing through one another. Depending upon both your seeing conditions and aperture, Abell 426 may reveal anywhere from 10 to 24 small galaxies that range to close to magnitude 15. Given the fact that there are around 233 galaxies in this cluster alone, it’s a privilege to be able to spot a few!

Abell 426 has been a longstanding favourite of mine. It is a curious galaxy cluster in the respect that the finer the night, the more galaxies will reveal themselves. The first study lays right in the field with a star and the NGC 1224 requires wide aversion. It is faint, round, and shows some concentration toward the nucleus with patience. Held indirect, this small galaxy has a UGC-like signature. Next stop on the hop is the NGC 1250 which is very diffuse, small and requires wide aversion. While allowing the eye to bounce around the field, it is possible to make out a slight north/south tilt to this galaxy that may indicate it to be a spiral. Curiously enough, it is during this motion that a pinprick of a nucleus can be detected. Pushing on toward the heart of the Perseus Galaxy cluster, the next destination is a chain of three. First study mark is the NGC 1259. Extreme aversion only… Very, very diffuse and faint, it can only be caught by focusing attention on the tiny star in the westward drift. The NGC 1260 only requires slight aversion, however. It is small and somewhat diffuse – definitely ovoid in structure – as well as the easiest to see of these three! The NGC 1264 also requires very wide aversion. Very faint and diffuse, very round – and very challenging! Now, triangulating with this series, it’s time to go for the NGC 1257 – very faint, diffuse and small with a concentration toward the core, it holds a little surprise – there’s a tiny star at the northeast end that allows one to see upon wide aversion that the galaxy itself seems to migrate to the northeast/southwest.

From here we have the option of continuing on the same trajectory or doing a lateral “move”. Past experience dictates that maps don’t always reveal everything there is to be seen in such a cluster including galaxies that masquerade as stars. The “heart” of Abell 426 is so dense that identification is extremely difficult! The NGC 1271 skirts the most populated part of this Abell cluster and requires super wide aversion to detect a very faint, very small patch that is barely visible. Even experience can draw nothing more than a slightly regular contrast change in this area. Next up is an extremely challenging triple – the NGC 1267, NGC 1268 and NGC 1269 are three incredibly tiny, very diffuse round gems that would be totally indistinguishable at lower power. NGC 1273 is faint – it requires aversion, but the brighter core region holds up to indirect vision. The NGC 1272 is also round – almost planetary in appearance. The NGC 1270 is very diffuse and takes wide aversion. It contains a very small, almost stellar nucleus. NGC 1279 is faint, diffuse, and stretches just ever so slightly, like a thin smear held at slight aversion to the north/south. It is even with no nucleus present. The NGC 1274 is very faint and very diffuse, even, and is best seen while concentrating on the NGC 1279 – revealing an incredibly small, misty oval. The NGC 1275 is very bright compared to all the previous studies. It most definitely has a bright and easily held direct nucleus. Going for a pair, we find the NGC 1282 to be diffuse, slight in size and quite ovoid – very even in structure with no hint of a nucleus even a full avert. The companion, NGC 1283, is very diffuse and we probably couldn’t see it except for there are some small field stars that triangulate in this area that leads to its foggy apppearance. Now for the NGC 1294 and NGC 1293 – wide aversion shows two round fuzzies with prickly nucleus structure. The pair looks like two impossibly small dandelions waiting to be scattered on the cosmic winds…

Best of luck on your Abell quest!

Wednesday, March 2 – How about tonight if we relax a bit and look for an open cluster that is viewable in binoculars and small scopes for the majority of both the northern and southern hemispheres? Our marker for this hop will be Xi Puppis and you will find M93 approximately two finger-widths (two degrees) northwest and almost right on the galactic equator.

Cataloged by Charles Messier in March of 1781, this wonderfully bright grouping (overall magnitude 7) of around 80 stars contains a wealth of various stars types that are roughly around 3400 to 3600 light years away. In binoculars the view is incredibly rich, but a telescope adds so much more! Towards the center, the viewer will note a wedge-shaped collection. At the heart of this is an easy double star and another on the western edge. The very brightest of these stars are young, hot and blue with a stellar population quite similar to the Plieades. How old you ask? A very modest one million years….

Thursday, March 3 – Get up early! There will be occultations galore for North America! Starting with the east coast, the Moon will occult Sigma Scorpii in the wee hours. Check out IOTA for specifics. On a broader note, (and the same morning!) the Moon will also occult Antares just a few hours later. It doesn’t matter if you are not into critical timing, you really should take advantage of this opportunity. Watching this kind of event is incredibly inspiring – even if you just view it with your eyes!

Tonight let’s try something a bit different! We’ll be heading about a degree and a half south/southwest of Alpha Monocerotis to find a magnitude 10 open cluster known as Melotte 72. Achievable in a good 6 to 10 inch scope, this loose collection of around 50 or so stars appears in a wonderful “delta wing” pattern! Continuing another degree and a half south will bring you to 7th magnitude Melotte 71. Easily capturable in the small scope, this unique small cluster contains around 100 stars. Remember where you found them, for this will be our guide to other studies!

Friday, March 4 – In 1835, Giovanni Schiaparelli opened his eyes for the very first time and opened ours with his accomplishments! As the director of the Milan Observatory, Schiaparelli (and not Perceval Lowell) was the fellow who popularized the term “Martian canals” somewhere around the year 1877. Far more importantly, Schiaparelli was the man who made the connection between the orbits of meteoroid streams and the orbits of comets almost eleven years earlier!

How about if we take a look at some comets tonight?

C/2004 Q2 Machholz is still holding strong and still viewable with just binoculars. Happily turning around Polaris, the “Magnificent Machholz” will be quite near the Cepheus/Camelopardalis border. C/2003 K4 LINEAR is still within large binocular range and can be found north of Tau 5 Eridanus. C/2005 A1 LINEAR makes a spectacular morning appearance for the small scope just south of Alpha Apus. In the north, comet C/2003 T4 LINEAR should have brightened to magnitude 9 and be very near Kappa Delphini in the hours before dawn. 141P/Machholz scoots into Aquarius for those around 40 degrees just after sunset, but will be a challenge at magnitude 10. Break out the big scopes and see if you can pick out 12th magnitude 78P/Gehrels so close to Theta 1 and Theta 2 Tauri… And since you’ve got the power out, take a look at 32P Comas/Sola just a few degrees from the Plieades!

Saturday, March 5 – Today is the birthday of Gerardus Mercator, famed mapmaker, who started his life in 1512. Mercator’s time was a rough one for astronomy, but despite a prison sentence and the threat of torture and death for his “beliefs”, he went on to design a celestial globe in the year 1551. If you are up early this morning, you can see the lunar feature named for Gerardus! While the most prominent crater of all will be Gassendi, we will use it as our starting point and head south. The dark expanse of Mare Humorum comes next and south of it and on the terminator you will find a heart-shaped area known as Palus Epidemiarum. On its northern shore you will see the outlined circle of crater Campanus. On this crater’s southeast border and mostly shadowed is the remains of Mercator!

Tonight let’s head back to Alpha Monocerotis. Remembering our “drop” for Mel 71 and 72, continue south about 2 more degrees. In the finderscope, you will see an L-shaped collection of 4 stars. Going to the eyepiece at low power – wide field, you are in for a double treat as we view two open clusters. The northernmost is NGC 2423, but the most interesting (and bright!) is more commonly known as M47.

M47 was known long before Messier’s time because it approaches unaided eye visibility. When Charles discovered this 5th magnitude beauty February 19, 1771 he described it as a brighter neighbor of the M46, but incorrectly logged its position! Thus was born the “missing Messier” until 1934 when Oswald Thomas identified it. It’s rather funny to note that because of a “messy mistake” that William Herschel also discovered it some fourteen years later! Even the later Herschel and Dreyer had problems with this one… But you won’t have any problems as you view this bright cluster in either binoculars or telescope! It is a loose open cluster around 78 million years old that contains around 50 stars of various magnitudes in a region about the same size of the full moon. At roughly 1600 light years away, you might even get a glimpse of an orange giant or two, along with beautiful double Sigma 1121 in its center!

Sunday, March 6 – Although almost no one likes to get up early on a Sunday morning, set your alarm for around 5:00 am. and carpe diem! This morning the splendid remaining crescent of the Moon will put on a spectacular showing called a “conjunction” with the Red Planet – Mars! You’ll find the stars of summer have quietly moved since since we viewed them last and Mars is now in Sagittarius. Shining every bit as brilliant as its namesake, Antares, Mars will be just a bit more than a fist’s width (6 degrees) above the Moon. Don’t miss it!

If you get a chance to see sunshine today, then celebrate the birthday of Joseph Fraunhofer who was born in 1787. As a German scientist, Fraunhofer was truly a “trailblazer” in terms of modern astronomy. His field? Spectroscopy! After having served his apprenticeship as a lens and mirror maker, Fraunhofer went on to develop scientific instruments, specializing in applied optics. While designing the achromatic objective lens for the telescope, he was watching the spectrum of solar light passing through a thin slit and saw the dark lines which make up the “rainbow bar code”. Fraunhofer knew that some of these lines could be used as a wavelength “standard” so he began measuring. The most prominent of the lines he labeled with letters that are still in use today! His skill between optics, mathematics and physics led Fraunhofer to design and build the very first diffraction grating which was capable of measuring the wavelengths of specific colors and dark lines in his solar spectrum. Did his telescope designs succeed? Of course! His work with the achromatic objective lens is the design still used in modern telescopes!

And for our “pasta resistance” of the week? Let’s head right back to the area we’ve been studying and go about a degree and a half east/south east of the M47. Tonight we’ll be studying an object that once again is viewable to most of the northern and southern hemisphere and is bright enough to be caught in binoculars. Its name? M46!

Discovered on February 19, 1771 by Charles Messier, the M46 opened a new chapter for our hero as he had just published his first list. At a visual magnitude of 6, this rich galactic cluster could contain up to 500 members and is around 300 million years old. Slightly smaller than a lunar diameter, it will appear as a “dust ball” (along with the M47) to binoculars, but holds a wonderful surprise for the telescope! On its northern border is a “bright star” which under power turns into planetary nebula, NGC 2438. Is it actually part of the M46? Well, science thinks not. The planetary nebula is actually receding far faster than the stars around it. On the average, the M46’s distance is about 4600 light years, while the nebula is around 2900. The planetary itself takes more than a billion years to reach this point in evolution and our stellar “swarm” just isn’t quite that old! No matter how we “slice and dice” this particular deep sky object, the fact remains… We get two for the price of one! Two Messiers in the field for binoculars – and two DSOs in the field of view for telescopes!

Hey! Isn’t it great to enjoy dark skies again? I love the Moon, but there’s no place like space! Until next week? May all your journeys be at light speed! … ~Tammy Plotner

Posted on by Fraser Cain

Cargo Ship Ready for Liftoff with Station Supplies

The crew members aboard the International Space Station are winding down a week that saw them preparing for the arrival of a new cargo spacecraft and helping achieve a milestone in Station robotics operations, which has the potential for long-term exploration applications.

Expedition 10 Commander and NASA Station Science Officer Leroy Chiao and Flight Engineer Salizhan Sharipov spent part of the week packing the Russian Progress supply spacecraft with trash and other items no longer needed on the Station. They closed the hatch between Progress and the Zvezda Service Module this morning in advance of the ship’s undocking Sunday.

The unpiloted spacecraft will be undocked Sunday at 11:06 a.m. EST. A pair of engine firings will place the vehicle in an orbit a safe distance away from the Station to allow Russian flight controllers to conduct engineering tests before it is commanded to reenter the Earth’s atmosphere on March 9 and burn up. The Progress arrived at the Station in December, bringing food and supplies to Chiao and Sharipov.

The next Progress that will be sent to the Station, will be moved to its launch pad at the Baikonur Cosmodrome in Kazakhstan tomorrow for final preparations for its liftoff Monday at 2:09 p.m. EST. After a two-day journey, docking is scheduled on Wednesday, March 2, at 3:15 p.m. EST. NASA TV will provide live coverage of the docking beginning at 2:30 p.m. EST. This will be the 17th Progress to dock with the Station.

The new Progress is loaded with more than two tons of supplies and food, including 2,932 pounds of spare parts, equipment, experiment hardware and life support system gear, 386 pounds of propellent, 242 pounds of oxygen and air, and 1,071 pounds of water. Eighty six food containers are also loaded into the Progress, good for more than 160 days of additional provisions in the Station’s pantry above what is already on board.

Among the other key U.S. items being carried to the Station on the supply ship is a new heat exchanger device for the cooling of U.S. spacesuits in the Quest Airlock. It will replace a heat exchanger that introduced rust in the suits last year, canceling Station spacewalks out of the U.S. segment. The new component will be installed by Chiao next month and checked out by the next crew, Expedition 11, to permit the airlock to be used again this summer. Also being delivered are digital cameras and lenses that the Expedition 11 crew will use to collect imagery of the heat-protective tiles of the Shuttle Discovery during its approach to the Station during this spring’s Return to Flight mission, STS-114, prior to docking. That imagery will assist in helping mission managers determine whether Discovery’s thermal protection system is intact and able to support a safe return to Earth.

Earlier today, engineers completed a two-day test of new software that was loaded into the Canadarm2 robotic arm last month to allow remote control operation of the space crane from Mission Control, rather than by the crew on board. The test was declared a success.

Chiao stood by at the robotic work station in the Destiny laboratory, ready to take over manual operation of the arm if necessary, but the automated commands loaded into the arm enabled Canadarm2 to move effortlessly throughout the demonstration. Its shoulder and wrist joints and its latching end effector were all exercised, verifying a new capability that may yield valuable data for designers of more complex robotic hardware for spacecraft that will support the Vision for Space Exploration.

Chiao also installed a rotor pump in one of the U.S. space suits on the Station today to configure it properly for its return to Earth on the STS-121 Shuttle mission to the outpost targeted for mid-July.

On the research front, Chiao conducted a session this week with the Dust and Aerosol Measurement Feasibility Test, or DAFT. The experiment, developed at NASA’s Glenn Research Center in Cleveland, Ohio, is designed to test the effectiveness of a device that counts ultra-fine dust particles in a microgravity environment. This is a precursor to the next generation of fire detection equipment for space exploration vehicles.

The device, called a P-Trak®, counts the dust particles by passing dust-laden air through a chamber of vaporous isopropyl alcohol. When a droplet of alcohol condenses over an ultra-fine dust particle, the particle becomes large enough to break the light beam and be counted. NASA’s payload operations team at NASA’s Marshall Space Flight Center coordinates science activities on Space Station.

Information about crew activities on the Space Station, future launch dates and Station sighting opportunities from Earth, is available on the Internet at:

http://spaceflight.nasa.gov/

The next International Space Station Status report will be issued on Monday, Feb. 28 following the ISS Progress 17 launch, or earlier if events warrant.

Original Source: NASA News Release

Posted on by Fraser Cain

Rainbows on Titan

When the European Space Agency’s Huygens probe visited Saturn’s moon Titan last month, the probe parachuted through humid clouds. It photographed river channels and beaches and things that look like islands. Finally, descending through swirling fog, Huygens landed in mud.

To make a long story short, Titan is wet.

Christian Huygens wouldn’t have been a bit surprised. In 1698, three hundred years before the Huygens probe left Earth, the Dutch astronomer wrote these words:

“Since ’tis certain that Earth and Jupiter have their Water and Clouds, there is no reason why the other Planets should be without them. I can’t say that they are exactly of the same nature with our Water; but that they should be liquid their use requires, as their beauty does that they be clear. This Water of ours, in Jupiter or Saturn, would be frozen up instantly by reason of the vast distance of the Sun. Every Planet therefore must have its own Waters of such a temper not liable to Frost.”

Huygens discovered Titan in 1655, which is why the probe is named after him. In those days, Titan was just a pinprick of light in a telescope. Huygens could not see Titan’s clouds, pregnant with rain, or Titan’s hillsides, sculpted by rushing liquids, but he had a fine imagination.

Titan’s “water” is liquid methane, CH4, better known on Earth as natural gas. Regular Earth-water, H2O, would be frozen solid on Titan where the surface temperature is 290o F below zero. Methane, on the other hand, is a flowing liquid, of “a temper not liable to Frost.”

Jonathan Lunine, a professor at the University of Arizona, is a member of the Huygens mission science team. He and his colleagues believe that Huygens landed in the Titan-equivalent of Arizona, a mostly-dry area with brief but intense wet seasons.

“The river channels near the Huygens probe look empty now,” says Lunine, but liquids have been there recently, he believes. Little rocks strewn around the landing site are compelling: they’re smooth and round like river rocks on Earth, and “they sit in little depressions dug, apparently, by rushing fluids.”

The source of all this wetness might be rain. Titan’s atmosphere is “humid,” meaning rich in methane. No one knows how often it rains, “but when it does,” says Lunine, “the amount of vapor in the atmosphere is many times that in Earth’s atmosphere, so you could get very intense showers.”

And maybe rainbows, too. “The ingredients you need for a rainbow are sunlight and raindrops. Titan has both,” says atmospheric optics expert Les Cowley.

On Earth, rainbows form when sunlight bounces in and out of transparent water droplets. Each droplet acts like a prism, spreading light into the familiar spectrum of colors. On Titan, rainbows would form when sunlight bounces in and out of methane droplets, which, like water droplets, are transparent.

“Their beauty [requires] that they be clear….”

“A methane rainbow would be larger than a water rainbow,” notes Cowley, “with a primary radius of at least 49o for methane vs 42.5o for water. This is because the index of refraction of liquid methane (1.29) differs from that of water (1.33).” The order of colors, however, would be the same: blue on the inside and red on the outside, with an overall hint of orange caused by Titan’s orange sky.

One problem: Rainbows need direct sunlight, but Titan’s skies are very hazy. “Visible rainbows on Titan might be rare,” says Cowley. On the other hand, infrared rainbows might be common.

Atmospheric scientist Bob West of NASA’s Jet Propulsion Laboratory explains: “Titan’s atmosphere is mostly clear at infrared wavelengths. That’s why the Cassini spacecraft uses an infrared camera to photograph Titan.” Infrared sunbeams would have little trouble penetrating the murky air and making rainbows. The best way to see them: infrared “night vision” goggles.

All this talk of rain and rainbows and mud makes liquid methane sound a lot like ordinary water. It’s not. Consider the following:

The density of liquid methane is only about half the density of water. This is something, say, a boat builder on Titan would need to take into account. Boats float when they’re less dense than the liquid beneath them. A Titan-boat would need to be extra lightweight to float in a liquid methane sea. (It’s not as crazy as it sounds. Future explorers will want to visit Titan and boats could be a good way to get around.)

Liquid methane also has low viscosity (or “gooiness”) and low surface tension. See the table below. Surface tension is what gives water its rubbery skin and, on Earth, lets water bugs skitter across ponds. A water bug on Titan would promptly sink into a pond of flimsy methane. On the bright side, Titan’s low gravity, only one-seventh Earth gravity, might allow the creature climb back out again.

Back to boats: Propellers turning in methane would need to be extra-wide to “grab” enough of the thin fluid for propulsion. They’d also have to be made of special materials resistant to cracking at cryogenic temperatures.

And watch out for those waves! European scientists John Zarnecki and Nadeem Ghafoor have calculated what methane waves on Titan might be like: seven times taller than typical Earth-waves (mainly because of Titan’s low gravity) and three times slower, “giving surfers a wild ride,” says Ghafoor.

Last but not least, liquid methane is flammable. Titan doesn’t catch fire because the atmosphere contains so little oxygen–a key ingredient for combustion. If explorers visit Titan one day they’ll have to be careful with their oxygen tanks and resist the urge to douse fires with “water.”

Infrared rainbows, towering waves, seas beckoning to sailors. Huygens saw none of these things before it plopped down in the mud. Do they really exist?

“…there is no reason why the other Planets should be without them.”

Original Source: Science@NASA

Posted on by Fraser Cain

Cassini Images Saturn’s Radiation Belts

Using an innovative camera on NASA’s Cassini spacecraft, scientists have captured images of a radiation belt inside the rings of Saturn and have the clearest picture yet of the planet’s giant magnetosphere, according to a mid-year report of the spacecraft published today in the journal Science.

The Cassini spacecraft entered Saturn’s orbit in July 2004, kicking off a four-year study of the sixth planet from the sun. Among the 12 science instruments on the spacecraft is the Magnetospheric Imaging Instrument (MIMI) — developed by the Johns Hopkins University Applied Physics Laboratory (APL) — which scientists are using to study the energetic charged particle environment at Saturn and obtain images of the ringed planet’s magnetosphere.

“Every time we fly a new instrument in space, it reveals new vistas of whatever object we happen to be studying,” says Dr. Stamatios (Tom) Krimigis, principal investigator for the MIMI experiment, of APL.

This time, says Krimigis, the MIMI instrument has enabled scientists to “visualize the invisible” — to “see” the plasma and radiation belts in Saturn’s environment in an image; to discover that the belts are more intense on the night-side of the planet; that there is an unexpected radiation belt inward of the “D” ring, the fourth major ring closest to the tenuous upper atmosphere of the planet; and that there is a virtual soup of ions that derive from the dissociation of water, most likely due to radiation impacting the rings.

These images were captured during Saturn orbit insertion with MIMI’s Ion and Neutral Camera (INCA), which measures the three-dimensional distribution, velocities and rough composition of magnetospheric and interplanetary ions for regions in which the energetic ion fluxes are very low. It also provides a global view of the energetic neutral emission of hot plasmas in the Saturnian magnetosphere, measuring the composition and velocities of those energetic neutrals for each image pixel.

“By detecting various energetic particles and discriminating among them according to energy and mass, the camera is able to obtain remote images of the global distribution of these particles,” says Dr. Donald Mitchell of APL, who leads the camera science team.

“Using INCA, we also discovered a radiation belt in a place where no spacecraft can go — inside the planet’s rings,” says APL’s Dr. Ed Roelof, a coinvestigator on the MIMI team. “We never knew this belt existed, but we saw it and were able to determine some of its properties and characteristics.”

The properties of the main radiation belts are perhaps among the more significant of the findings, says Dr. Doug Hamilton of the University of Maryland , College Park, who led the instrument team measuring the composition. “It’s comprised mostly of oxygen and water products,” he says. “That is most likely the result of the bombardment of the planet’s rings and the icy moons by the radiation trapped in Saturn’s magnetic field. And by this bombardment, the water is released and it becomes charged.”

According to Krimigis, the ability to visualize a planet’s magnetosphere will enable scientists to better monitor space weather. “This will benefit science and, in the case of Earth, may lead to space weather forecasts that will give advance warning of electromagnetic storms, which in the past have disrupted communications and crippled electrical power grids.”

In addition to Krimigis, Mitchell and Roelof, research team members at APL and co-authors on the Science paper, “Dynamics of Saturn’s Magnetosphere from MIMI During Cassini’s Orbital Insertion,” include Stefano Livi, Barry Mauk, Christopher Paranicas, Pontus Brandt, Andrew Cheng, Teck Choo, John Hayes, Stephen Jaskulek, Edwin Keath, Martha Kusterer, David LaVallee, Richard McEntire, Joachim Saur, Franklin Turner and Donald Williams.

The Cassini-Huygens mission is a cooperative project of NASA, ESA and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA. The MIMI team includes investigators and expertise from APL; the University of Maryland, College Park; University of Kansas, Lawrence; University of Arizona, Tucson; Bell Laboratories, Murray Hill, N.J.; the Max Planck Institute for Solar System Research, Lindau, Germany; and the Centre d’Etude Spatiale des Rayonnements in Toulouse, France.

Original Source: JHU News Release