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Astrodev.uchicago.edu

Cosmology - The Study of the Universe
By the University of Chicago


* Kicp.uchicago. * Sciencechicago.com * Events


Cosmology is the study of the Universe as a whole and its history since the beginning. Here you will find our on-going research to study cosmological phenomena, such as the inflation of the universe, the growth of structures, and the cosmic microwave background radiations. (more)

* Related Research Projects by Universities and Astrophysic Agencies:

• COSMUS
• ESA's Planck Mission
• Extragalactic Astronomy
• MSAM-TopHAT Experiment
• Dark Energy Survey (DES)
• Microwave Anisotropy Probe (MAP)
• Degree Angular Scale Interferometer (DASI)
• Stratospheric Observatory For Infrared Astronomy (SOFIA)

• High Energy Astrophysics
• Sloan Digital Sky Survey (SDSS)
• South Pole Telescope (SPT)
• Sunyaev-Zeldovich Array (SZA)
• Joint Institute for Nuclear Astrophysics (JINA)
• Interferometric Sunyaev-Zel'dovich Effect Imaging Experiment (SZE)
• Very Energetic Radiation Imaging Telescope Array System (VERITAS)
• Center for Magnetic Self Organization in Astrophysical and Laboratory Plasmas (CMSO)




Understanding the Cosmos is undergoing a revolution with fields as diverse as high energy physics and astronomy converging in theory and experiments.

• P. A. Observatory: A Century-Old Mystery Unveiled: The Most Energetic Particles to Reach Earth Come From Outside the Milky Way (more)

- Cosmic rays are energetic subatomic particles from space that can have energies 10 million times greater than those created by man-made particle accelerators. Their origin has been a mystery for almost a century, ever since their discovery in 1912. The Pierre Auger Observatory in Argentina, an international effort involving 17 countries and hundreds of scientists, including an active group at KICP led by Auger Spokesperson Emeritus James Cronin and University of Chicago faculty members Angela Olinto and Paolo Privitera, has recently measured the arrival directions of the highest energy cosmic rays. The pattern in the sky created by these particles reveals that the most energetic particles do not come from every direction in space.




- The arrival directions of the 27 highest energy cosmic rays detected by Auger projected onto the celestial sphere of our Universe (black circles of radius 3.1o). The positions of 472 AGN within 75 Megaparsecs are shown as red stars.

The highest energy particles are very rare: over an area of one square kilometer, only one particle per century reaches the Earth. To meet this challenge, the Pierre Auger Observatory covered an area of 3000 km2 and completed its construction in early 2008. Since it began operation in January 2004, the Auger Observatory has collected 27 particles with energies above 5.7 x 1019 eV. These particles are the first to show a positive correlation between nearby active galaxies (AGNs) and the highest energy cosmic rays. Their arrival directions correlate well with the distribution of active galaxies located less than 180 million light years (or 1.7 x 1021 km) from Earth. These findings are summarized in recent publications by the Pierre Auger Collaboration in Science and Astroparticle Physics. MORE »




- Pierre Auger Observatory surface detector for cosmic energetic particles with the Andes in the background.


• Science Magazine: Correlation of the Highest-Energy Cosmic Rays with Nearby Extragalactic Objects
• Kavli Institute: Correlation of the highest-energy cosmic rays with the positions of nearby active galactic nuclei (Pdf)

Accessexcellence.org

Astrobiology and the Origins of Life
Narrative Index of a talk
by Dr. Stanley Awramik


• TIME: How Life Began


Astrobiology is a new field that discusses the origins, the distribution and the future of life in the universe. Two breakthroughs of importance to astrobiology are evidence for the possibility of the existence of life in the past on Mars and the discovery of planets around nearby stars. Speculation and early experiments on the origins of life from Charles Darwin, Alexander Oparin, H.B.S. Haldane contributed to a breakthrough experiment by Stanley Miller. Miller took non-living material that was on the early Earth--hydrogen, methane, ammonia, and water--provided an energy source and produced amino acids. In the 44 years since Miller's experiment, scientists such as Juan Oró and Tom Cech have produced nucleic acid bases and riboenzymes but no self-replicating life or organism or cell has yet been produced in the laboratory.

What do we know about the timeline for origins of life on Earth? Earth formed from the accretion of planetesimals about 4.6 billion years ago. Current estimates are that it took 200 million years, or to about 4.4 billion years ago, until the Earth had a solid crust, had water and was a habitable environment for life. The oldest rocks are now placed at about 3.96 billion years and the oldest fossils are from 3.5 billion years. Four hundred million years of geological record are missing. This could be the origin of life window.

The oldest fossils are about 3.5 billion years; however, in rocks dated 3.8 billion years, analyses of isotopes of carbon suggest that carbon fixation and maybe even photosynthesis was around then. So now we have evidence of life at 3.8 billion years ago, some rocks at 3.96 billion and habitability maybe as far back as 4.4 billion. Think of the primitive Earth crust-- heat, volcanic activity, radioactivity, energy from impacts of asteroids and comets, water-- as just one big chemical evolution experiment. The fossils from 3.5 billion years are thought to be the remains of Cyanobacteria. Microbiologists and molecular biologists have concluded that Cyanobacteria were one of the last major groups of bacteria to evolve. That would suggest that much of the microbial evolution at the phylum or division level may have already been around by 3.5 billion years.

If 3.8 billion years is the date of the last common ancestor that leaves 300 million years for life to evolve to the level of Cyanobacteria. Microbiologists, however, believe 300 million years is too short a period of time for that level of evolution to have occurred. So where does that put the origin of life? Let's go back to that exciting breakthrough mentioned at the start of this talk--the alleged microfossils found in the Martian meteorite in Antarctica dated 3.6 billion years. The fossil tubular structures are on the order of 40 or 50 nanometers in diameter. Based on our understanding of genetic systems on Earth, we're not sure if a cell that small could contain enough genetic material to exist. We are left with questions and the understanding that there is a need for a cosmological perspective when exploring the origins of life. This brings us to the new field of astrobiology.



Spaceref: Astrobiology (Space News)

• Astrobiology: Its Origins and Development
• Astrobiology - Mars • Origins of Life in the Universe
• TIME: Will We Figure Out How Life Began?
• Complex systems and Mars missions help understand how life began (more)

On the Net:


Blueprint • structures in the Universe. By the WMAP

• Cosmic WMAP • Cosmic Slides • Cosmology History
• Videos: Public lectures on Cosmology and Science • Links: Space Telescopes
• Astrobiology Research Articles: http://astrobiology.nasa.gov/nai • http://map.gsfc.nasa.gov/universe

Sir Roger Penrose and Prof. Frank Wilczek share their scientific views in two new presentations, now viewable online.
By Canada's Perimeter Institute for Theoretical Physics


"Before the Big Bang: Is There Evidence For Something And If So, What?" features Sir Roger Penrose, Oxford, examining a great deal of evidence confirming the existence of a very hot and dense early stage of the universe. Much of this data comes from a detailed study of the cosmic microwave background (CMB) - radiation from the early universe that was most recently measured by NASA's WMAP satellite. But the information presents new puzzles for scientists. One of the most blatant examples is an apparent paradox related to the second law of thermodynamics. Although some have argued that the hypothesis of inflationary cosmology solves some of the puzzles, profound issues remain. In this multi-media presentation, Professor Penrose shows a very different proposal, one that suggests a succession of universes prior to our own. He also presents recent analysis of the CMB data that could have profound bearing on these issues.


• Lecture Video: Before the Big Bang...
• Lecture Video: Anticipating A New Golden Age


"Anticipating A New Golden Age" with Nobel Laureate Prof. Frank Wilczek, MIT, begins with a Core Theory of matter (aka "standard model"), born in the 1970s, a Golden Age for fundamental physics. To date it has passed every experimental test, extending – by many orders of magnitude – to higher energies, shorter distances, and greater precision than were available in the 1970s. Yet we are not satisfied, because the Core Theory postulates four separate interactions and several different kinds of matter, and its equations are lopsided. In this online PI Public Lecture, Prof. Wilczek shows powerful and extremely beautiful ideas for restoring unity and symmetry to the fundamental laws. These ideas are firmly rooted in empirical reality, but at present the evidence for them is circumstantial. The Large Hadron Collider (LHC) will provide critical tests. If Nature has been teaching, not teasing, discoveries at the LHC will inaugurate a new Golden Age, bringing our fundamental understanding of the physical world to a new level.


• Lecture Video: The Florentine Heretic? Galileo, the church and the cosmos
• Lecture Video: Life, the Universe, and the Search for Extraterrestrial Intelligence (SETI)
• To view other presentations, visit: http://www.perimeterinstitute.ca/Outrea ... _Lectures/ (more)


• Links

• A Christian believers explanation of the "Big Bang" theory about the beginning of the universe. - (more)

Science News

Analysis of radiation from the "Big Bang" point to a possible new type of field in early universe

Lopsided universe demands different explanation
By Ron Cowen, December 23rd, 2008


• WMAP Microwave light • Afterglow of 'Big Bang' detected (more)


- Full-sky temperature map taken by the Wilkinson Microwave Anisotropy Probe (WMAP) an Explorer mission launched by NASA in June 2001. The Wilkinson Microwave- Anisotropy - Probe also known as the Microwave Anisotropy Probe (MAP), and Explorer 80 measures the temperature of the 'Big Bang's remnant radiant heat. In cosmology, the cosmic microwave background radiation CMB (also CMBR, CBR, MBR, and relic radiation) is a form of electromagnetic radiation filling the universe. In simple terms, when looking at the sky with a radio telescope, the space between the stars and galaxies is not black. Instead there is a very faint glow, almost exactly the same in all directions, not coming from any star or galaxy. The cosmic microwave background radiation map depicts tiny hot and cold spots, no more than 200 microkelvins above or below the average temperature of this cosmic microwave background. Possible asymmetries in the data --- slightly larger deviations in the average temperature over one half of the sky than the other --- may indicate that the standard model of the origin of the universe may need to be modified. MORE »

"In 1922, Alexander Friedmann derived his Friedmann equations from Einstein's field equations, showing that the universe might expand at a rate calculable by the equations. The parameter used by Friedmann is known today as the scale factor which can be considered as a scale invariant form of the proportionality constant of Hubble's Law. Georges Lemaître independently found a similar solution in 1927. The Friedmann equations are derived by inserting the metric for a homogeneous and isotropic universe into Einstein's field equations for a fluid with a given density and pressure. This idea of an expanding spacetime would eventually lead to the Big Bang and Steady State theories (also known as the Infinite Universe theory or continuous creation) of cosmology." MORE »


• CMB Research Topics • Web links

"Modern physical cosmology as it is currently studied first emerged as a scientific discipline in the period after the Shapley-Curtis debate and discoveries by Edwin Hubble of a cosmic distance ladder when astronomers and physicists had to come to terms with a universe that was of a much larger scale than the previously assumed galactic size. Theorists who successfully developed cosmologies applicable to the larger-scale universe are remembered today as the founders of modern cosmology. Among these scientists are Arthur Milne, Willem de Sitter, Alexander Friedman, Georges Lemaitre, and Albert Einstein." MORE »
____

Related articles:
• Discovery of the Cosmic Microwave Background • Apeiron Online Journals
• Cosmic background radiation, temperature of intergalactic space, blackblody radiation
• Wikipedia: Dr. Halton Chr. Arp, American astronomer critic of the Big Bang. • Fingers of God in an Expanding Universe


• New satellite data on universe’s first trillionth second

- Scientists peering back to the oldest light in the universe have new evidence for what happened within its first trillionth of a second, when the universe suddenly grew from submicroscopic to astronomical size in far less than a wink of the eye. MORE »

• WMAP and its discovery
- Well, it was thought that if it was a hot big bang, then there should be some heat left over from the earliest times of the creation, sort of like heat left over in a kitchen long after the oven has been turned off. This was hypothesized many years ago and the leftover heat was called the cosmic background radiation. And it was first vaguely detected back in the 1960's. But in the early 1990's, when technology finally caught up with theory, a satellite called COBE, with very sensitive equipment, was able to see this background radiation all around us at exactly the cooled down temperature it was predicted to be - the "afterglow" of a hot big bang. And there was much rejoicing. Then it was time to send up a new, much more sensitive satellite that could see the background radiation in much greater detail. Could it see traces of the proposed great inflation, too?

The Wilkinson Microwave Anisotropy Probe - WMAP as its also known, gave us in 2003 an amazing view of the universe that showed the details COBE could not. And all this seemingly dull cosmic background radiation picked up from WMAP was actually a treasure trove of complicated information that answered some of the great hidden mysteries of the cosmos. Among other things astronomers could now determine were the age of the universe (13.74 billion years), and its composition (4% atoms, 22% dark matter, 74% dark energy). It was a watershed moment for cosmology. And there was much rejoicing. MORE


• Cosmology: http://people.physics.tamu.edu • Rochester.edu: A Short Course on Cosmology • Physical cosmology

Science Mag

• ABC: Black holes 'fuel-efficient engines' » Science: Video

Mysterious as they are, every black hole apparently shares one identical feature. A new survey of more than 200 of the flat, circular zones of matter that feed the cosmic beasts finds that all of these so-called accretion disks are the same shape, as seen in this picture, regardless of how the black hole formed or how heavy it is. Reporting in an upcoming issue of the Monthly Notices of the Royal Astronomical Society, astrophysicists say this find could help them understand some of the fundamentals of the galactic monsters--such as how they manage to accumulate enough mass to warp time and space so severely--which so far cannot be observed directly. MORE »


Related articles:

• AP: Scientists: Black hole helps spawn stars
• Science Daily: Seeing the shape of material around black holes for first time
• Upper mass limit for black holes? • The Astrophysical Journal • The Astrophysical Journal Letters

On the Net: http://maxim.gsfc.nasa.gov/docs/science - http://astrophysics.gsfc.nasa.gov • www.amptek.com

Dailyexcelsior.com

The Invention that Changed our Minds
By G. V. Joshi


• Geocentric model of Universe • Weblinks


The geocentric theory of Ptolemy which maintained that the Earth on which we live, was the center of the universe, dominated ancient and medieval science. It seemed evident to early astronomers that the rest of the universe moved about a stable, motionless Earth, which appeared like a huge flat disk. The Sun, Moon, the then known five planets, and stars could be seen moving about Earth along circular paths day after day year after year. It appeared logical to believe that Earth was stationary, for nothing seemed to make it move. Finally, geocentrism was in accordance with the theocentric (God-centered) world view, dominant in the Middle Ages, when science was a part of theology.

The geocentric model created by Greek astronomers assumed that the celestial bodies moving about the Earth followed perfectly circular paths. Greek mathematicians and philosophers regarded the circle as the perfect geometric figure and consequently the only one appropriate for celestial motion. To explain this motion of the planets (called retrograde in astronomy), Greek astronomers like Ptolemy (90 A. D.-168 A. D.), devised complicated models in which planets moved along circles (called epicycles) that were superimposed on circular orbits about the Earth. These geocentric models were able to explain, for example, why Mercury and Venus never move more than 28° and 47° respectively from the Sun. As astronomers improved their methods of observation and measurement, the models became increasingly complicated, with constant additions of epicycles. Nonetheless, the geocentric theory persisted.


• www.rmutphysics.com

- "This period of history (scientific revolution in astronomy) could be said to have begun with the publication of Copernicus' On the Revolutions of the Heavenly Spheres (1543) and to have ended with the publication of Newton's Principia Mathematica (1687). It changed the world view from a geocentric, Earth-centred model, to a heliocentric, Sun-centred model." MORE »


In 1514, Copernicus first suggested a replacement for the geocentric system of Claudius Ptolemy. According to Copernicus, a heliocentric theory could explain the motion of celestial bodies more simply than the geocentric view. In the Copernican model, the Earth orbits the Sun along with all the other planets. Such a model could explain the retrograde motion of a planet without resorting to epicycles, and could also explain why Mercury and Venus never stray more than 28° and 47° from the Sun. However, Copernicus’s work did not spell the demise of geocentrism. The Danish astronomer Tycho Brahe (1546-1601), a brilliant experimental scientist whose measurements of the positions of the stars and planets surpassed any that were made prior to the invention of the telescope, proposed a model that attempted to serve as a compromise between the geocentric model and the Copernican model.

According to Dr A. L. Basham, the ancient Indian astronomers also knew of seven members of the solar system - the sun, the moon, Mercury, Venus, Mars, Jupiter and Saturn. Ancient astronomers followed the geocentric theory - that the earth was the centre of the universe - though, in 497 A.D. the Indian methematician and astronomer Aryabhatta had suggested that the earth revolved round the sun and rotated on its own axis. To spread his new knowledge about the objects in the sky, Galileo arranged the world’s first star-gazing parties with his telescope, to the rich and powerful in Venice and elsewhere. For the first time, people saw that the Moon was pockmarked with craters, that Saturn had strange rings around it and that Jupiter had moons of its own, and that even the sun had ugly spots.

All this annoyed the Pope. Galileo had to pay dearly for his so called sins, ultimately dying in disgrace under house arrest, a lonely, broken man. He had to publicly acknowledge that he had been wrong to have said that the Earth moves around the Sun. It is said that after his confession, Galileo quietly whispered “And yet, it moves.” The very year that Galileo died, a child was born (Isaac Newton) who finally completed the geocentric to heliocentric revolution. In the mean time another astronomer Johannes Kepler had developed his three laws of planetary movement around he Sun. Newton even invented a new type of telescope, the reflecting telescope, which is the basis of modern telescope technology. With the passage of time it was accepted that the Earth was not the center of the Universe. But only on 31 October 1992, Pope John Paul II expressed regret for how Galileo was treated, and officially conceded that the Earth was not stationary.


The United Nations has scheduled 2009 to be the International Year of Astronomy.

• History of Astronomy • Historyofscience.com

- "400 years ago, Galileo Galilei looked through a telescope and changed humanity’s view of the universe forever. He started a revolution that placed the Earth and Sun in their rightful place within a cosmos filled with innumerable stars and new distant worlds. In celebration of humankind’s first modern glimpse into the beautifully complex workings of our solar system and beyond, the world is celebrating 2009 the International Year of Astronomy." MORE »


On the Net:
• BBC News: Pope Benedict praises Galileo's astronomy
• Int. Year of Astronomy 2009: http://astronomy2009.us • aas.org • IYOA Global Projects • Videos / 2

• For the very latest astronomy news: http://www.universetoday.com
• For info on what's above your head from anywhere in the world: http://www.heavens-above.com
• Stanford Encyclopedia: Newton's Views on Space, Time, and Motion • Newton's Philosophiae Naturalis Principia Mathematica

BBC Science




- There was a time when scientists thought the universe had always existed (Steady State Theory).
New evidence has convinced almost all cosmologists that the Universe somehow had a beginning.


The Big Bang theory tells us how the Universe began and is evolving. In essence, it is a theory that was created to explain two facts that we know about the Universe - it is gradually expanding and cooling. In the 1920s, Edwin Hubble found that galaxies far from our own Milky Way are moving away from us. In fact, the further away galaxies are, the faster they are receding. So he concluded that the whole Universe must have been expanding. Working backwards this means that at one stage the Universe must have come from a single point. We also know that the Universe is cooler now than in the past.

In the 1960s Arno Panzias and Robert Wilson detected the afterglow of the Big Bang, known as the cosmic microwave background, or CMB for short, which revealed that the Universe was once a very hot, hostile place. Both these discoveries led astronomers to deduce that the Universe began as an infinitely compact fireball. The Big Bang describes how this fireball grew to form all the stars and planets we see around us now.

Because of its name many people think of the Big Bang as a kind of explosion that happened at some specific point in space, but this isn't correct, as the Universe didn't spring from one central ignition point. Instead, during the Big Bang space was first created and then stretched. The easiest way to understand this tricky concept is to think of the Universe as a fruitcake in an oven. Imagine you are a bit of fruit inside the cake. As it bakes, the cake rises and all the other bits of fruit around you move further and further away. No matter whereabouts in the cake you are, everything around you is moving away at the same rate. But unlike the fruitcake, there is no centre to the Univers... MORE »

Related articles:
• Scienceclass: Origin of the Universe • Similar articles

Sciencedaily.com

What Can Swiss Cheese Teach Us About Dark Energy?
By ScienceDaily, Dec. 28, 2008


• Spacedaily News

- Is dark energy really real? Is our universe really accelerating? These questions hang around in the mind of Ali Vanderveld, a post-doctoral cosmologist at JPL. (Credit: Image courtesy of NASA-Jet Propulsion Laboratory)


— About 10 years ago, scientists reached the astonishing conclusion that our universe is accelerating apart at ever-increasing speeds, stretching space and time itself like melted cheese. The force that's pushing the universe apart is still a mystery, which is precisely why it was dubbed "dark energy." But is dark energy really real? Is our universe really accelerating? These questions hang around in the mind of Ali Vanderveld, a post-doctoral cosmologist at JPL. Vanderveld and her colleagues recently published a paper in the journal Physical Review looking at how giant holes in our "Swiss-cheese-like" universe might make space look as if it's accelerating when it's really not.

They concluded these holes, or voids, are not sufficient to explain away dark energy; nevertheless, Vanderveld says it's important to continue to question fundamental traits of the very space we live in. "Sometimes we take dark energy for granted," said Vanderveld. "But there are other theories that could explain why the universe appears to be moving apart at faster and faster speeds." Why do scientists think the universe is accelerating? A large part of the evidence comes from observations taken over the last decade or so of very distant, colossal star explosions called supernovae. JPL's Wide-Field and Planetary Camera 2 on NASA's Hubble Space Telescope contributed to this groundbreaking research. Astronomers had already figured out that space, since its inception about 13.7 billion years ago in a tremendous "Big Bang" explosion, is expanding.

But they didn't know if this expansion was happening at a constant rate, and even speculated that it could be slowing down. By examining distant supernovae billions of light-years away, scientists could get a look at how the expansion of space behaves over time. The results were baffling. The more distant supernovae were dimmer than predicted, which would suggest they are farther away than previously believed. If they are farther away, then this means the space between us and the supernovae is expanding at ever-increasing speeds. Additional research has since pointed to an accelerating universe. A group of researchers from Fermi National Accelerator Laboratory in Batavia, Ill., recently invoked what's called the Swiss-cheese model of the universe to explain why these supernovae might appear to be moving faster away from us than they really are. The universe is made up of lumps of matter interspersed with giant holes, or voids, somewhat like Swiss cheese. In fact, last year, astronomers at the University of Minnesota, Twin Cities, reported finding the king of all known voids, spanning one billion light-years.

In other words, it would take light -- which holds the title for fastest stuff in the universe -- one billion years to go from one side of the void to the other! The researchers at Fermi said these voids might lie between us and the supernovae being observed, acting like concave lenses to make the objects appear dimmer and farther than they really are. If so, then the supernova might not be accelerating away from us after all. Their theory claimed to provide a way in which dark energy might go poof. Vanderveld and her colleagues at Cornell University, Ithaca, N.Y., looked more closely at this theory and found a few "holes." The group at Fermi had assumed a bunch of voids would line up between us and the supernovae, but Vanderveld's group said, in reality, the voids would be distributed more randomly -- again like Swiss cheese. With this random distribution, the voids are not enough to explain away dark energy.

"The lumpiness of the universe could still be tricking us into thinking it's accelerating," said Vanderveld. "But we did not find this to be the case with our best, current models of the universe." There is, however, one other freakish possibility that could mean a void is creating the illusion of an accelerating universe. If our solar system just happened to sit in the middle of a void, then that void would distort our observations. Said Vanderveld, "It's really hard to tell if we're in a void, but for the most part this possibility has been ruled out." MORE »


• Sciencedaily: Looking For Extraterrestrial Life In All The Right Places
• First Stars In The Universe - Astronomers Reveal First Objects In Our Universe

Spaceref

NASA's Mars Rovers Near Five Years of Science and Discovery
By Spaceref, December 29, 2008


• Mars Rover • NASA Rovers Spirit and Opportunity: Five Years on Mars.


NASA rovers Spirit and Opportunity may still have big achievements ahead as they approach the fifth anniversaries of their memorable landings on Mars. Of the hundreds of engineers and scientists who cheered at NASA's Jet Propulsion Laboratory (JPL), in Pasadena, Calif., on Jan. 3, 2004, when Spirit landed safely, and 21 days later when Opportunity followed suit, none predicted the team would still be operating both rovers in 2009. "The American taxpayer was told three months for each rover was the prime mission plan," said Ed Weiler, associate administrator for NASA's Science Mission Directorate at NASA Headquarters in Washington. "The twins have worked almost 20 times that long. That's an extraordinary return of investment in these challenging budgetary times."

The rovers have made important discoveries about wet and violent environments on ancient Mars. They also have returned a quarter-million images, driven more than 13 miles, climbed a mountain, descended into craters, struggled with sand traps and aging hardware, survived dust storms, and relayed more than 36 gigabytes of data via NASA's Mars Odyssey orbiter. To date, the rovers remain operational for new campaigns the team has planned for them. "These rovers are incredibly resilient considering the extreme environment the hardware experiences every day," said John Callas, JPL project manager for Spirit and Opportunity. "We realize that a major rover component on either vehicle could fail at any time and end a mission with no advance notice, but on the other hand, we could accomplish the equivalent duration of four more prime missions on each rover in the year ahead."

Occasional cleaning of dust from the rovers' solar panels by Martian wind has provided unanticipated aid to the vehicles' longevity. However, it is unreliable aid. Spirit has not had a good cleaning for more than 18 months. Dust-coated solar panels barely provided enough power for Spirit to survive its third southern-hemisphere winter, which ended in December. "This last winter was a squeaker for Spirit," Callas said. "We just made it through." With Spirit's energy rising for spring and summer, the team plans to drive the rover to a pair of destinations about 200 yards south of the site where Spirit spent most of 2008. One is a mound that might yield support for an interpretation that a plateau Spirit has studied since 2006, called Home Plate, is a remnant of a once more-extensive sheet of explosive volcanic material. The other destination is a house-size pit called Goddard. "Goddard doesn't look like an impact crater," said Steve Squyres of Cornell University, in Ithaca, N.Y. Squyres is principal investigator for the rover science instruments. "We suspect it might be a volcanic explosion crater, and that's something we haven't seen before."



- On Mars. View from Southwest of Victoria Crater: This mosaic of frames from the navigation camera on NASA’s Mars Exploration Rover Opportunity gives a view to the northeast from the rover’s position on its 1,687th Martian day, or sol (Oct. 22, 2008). By that date, Opportunity had driven southwestward from Victoria Crater, beginning a long trek toward a larger crater, Endeavour. Image credit: NASA/JPL-Caltech MORE »


A light-toned ring around the inside of the pit might add information about a nearby patch of bright, silica-rich soil that Squyres counts as Spirit's most important discovery so far. Spirit churned up the silica in mid-2007 with an immobile wheel that the rover has dragged like an anchor since it quit working in 2006. The silica was likely produced in an environment of hot springs or steam vents. For Opportunity, the next major destination is Endeavour Crater. It is approximately 14 miles in diameter, more than 20 times larger than another impact crater, Victoria, where Opportunity spent most of the past two years. Although Endeavour is 7 miles from Victoria, it is considerably farther as the rover drives on a route evading major obstacles.

Since climbing out of Victoria four months ago, Opportunity has driven more than a mile of its route toward Endeavour and stopped to inspect the first of several loose rocks the team plans to examine along the way. High-resolution images from NASA's Mars Reconnaissance Orbiter, which reached Mars in 2006, are helping the team plot routes around potential sand traps that were not previously discernable from orbit. "The journeys have been motivated by science, but have led to something else important," said Squyres. "This has turned into humanity's first overland expedition on another planet. When people look back on this period of Mars exploration decades from now, Spirit and Opportunity may be considered most significant not for the science they accomplished, but for the first time we truly went exploring across the surface of Mars."

For more information about Spirit and Opportunity, visit: http://www.nasa.gov/rovers


Happy New Year From Cassini.!


• This week NASA celebrates the 40th Anniversary of Apollo 8 • Wikipedia Apollo 8
• NASA's Top Science, Exploration and Discovery Stories of 2008 • Earthrise, Apollo 8
• NASA LaRC Solicitation: Parachute Systems for Venus • www.nasa.gov/mission_pages
- NASA is developing multiple strategies for Venus exploration on the New Frontiers Program Announcement of Opportunity (2009).

Dec 23, 2008. Astronaut Michael Fincke, Expedition 18 commander, takes a picture of his own helmet visor with an astronaut digital still camera during a spacewalk on the International Space Station. Photo Credit: NASA

Dec 15: The Soyuz TMA 13 remains docked with the International Space Station, as photographed through the Zvezda service module window by one of the Expedition 18 crewmembers. Credit: NASA

- Cosmonaut Yury Lonchakov, Expedition 18 flight engineer, performs a task during the Dec. 23 spacewalk on the International Space Station. Credit: NASA

Space News: http://weatherspace.org

- Dec 15: The Soyuz TMA 13 remains docked with the International Space Station, as photographed through the Zvezda service module window by one of the Expedition 18 crewmembers. Credit: NASA


• Weatherspace: Next Intern. Space Station Crews Train at Korolev.
• NASA Assigns Crews for Space Shuttle Missions STS-130 and STS-131.

Weatherspace.org

Hubble Space Telescope Observes Dense Globular Cluster M13.
From Space and Astronautics News, December 4th, 2008



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


Like a whirl of shiny flakes sparkling in a snow globe, Hubble catches an instantaneous glimpse of many hundreds of thousands of stars moving about in the globular cluster M13, one of the brightest and best-known globular clusters in the northern sky. This glittering metropolis of stars is easily found in the winter sky in the constellation Hercules and can even be glimpsed with the unaided eye under dark skies.

M13 is home to over 100,000 stars and located at a distance of 25,000 light-years. These stars are packed so closely together in a ball, approximately 150 light-years across, that they will spend their entire lives whirling around in the cluster. Near the core of this cluster, the density of stars is about a hundred times greater than the density in the neighborhood of our Sun. These stars are so crowded that they can, at times, slam into each other and even form a new star, called a ‘blue straggler.’ The brightest reddish stars in the cluster are ancient red giants. These aging stars have expanded to many times their original diameters and cooled. The blue-white stars are the hottest in the cluster. Globular clusters can be found spread largely in a vast halo around our galaxy. M13 is one of nearly 150 known globular clusters surrounding our Milky Way galaxy.

Globular clusters have some of the oldest stars in the universe. They likely formed before the disk of our Milky Way, so they are older than nearly all other stars in our galaxy. Studying globular clusters therefore tells us about the history of our galaxy. This image is a composite of archival Hubble data taken with the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys. Observations from four separate science proposals taken in November 1999, April 2000, August 2005, and April 2006 were used. The image includes broadband filters that isolate light from the blue, visible, and infrared portions of the spectrum. MORE »

• Spitzer Space Telescope Observes Bow Shocks Around Stars.

- Mars Express High Resolution Stereo Camera image of Hebes Chasma. Hebes Chasma is an enclosed trough, almost 8000 m deep, in Valles Marineris, the Grand Canyon of Mars, showing Light Toned Deposits. This is an area where water is believed to have flowed. An analysis of data and images from Mars Express suggests that several Light Toned Deposits, some of the least understood structures on Mars, were formed when large amounts of groundwater burst on to the surface.

Scientists propose that groundwater had a greater role in shaping the martian surface than previously believed, and may have sheltered primitive life forms as the planet started drying up. Hebes Chasma is located at approximately 1 degree south and 282 degrees east. Image data was obtained on 16 September 2005 with a ground resolution of approximately 15 m/pixel. Credit: ESA/DLR/FU Berlin (G. Neukum)

- Courtesy of European Space Agency - www.space.gs