Ian O'Neill, Author at Universe Today

March 10, 2009December 24, 2015 by Ian O'Neill

Phoenix Team Divided: Are the Mars Liquid Water Observations a “Matter of Belief”?

Detail of the three controvercial images of the Phoenix Mars Lander's leg. Are they droplets of water? (Renno, et al., NASA)

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Last month, it was announced that in the few days after the landing of the Phoenix lander in May 2008, the camera attached to the robotic arm captured visual evidence of (what appeared to be) droplets of water, almost like condensation forming on the leg of the lander. In three images dated on sol 8, sol 31 and sol 44 of the mission, the droplets appear to move, in a fluid-like manner. Although a recent publication indicates this oddity could be a water-perchlorate mix (where the toxic salt acts as a potent anti-freeze, preventing the water from freezing and subliming), other members of the Phoenix team are very dubious, saying that there is another, more likely explanation…

One of the key components necessary for the survival of life on Earth is water, especially when the water is in a liquid state. This is an easy proposition on our planet, as the atmospheric pressures and temperatures are just right for the majority of water on Earth to be in a usable liquid state. Should liquid water be discovered on another planet however, where the conditions are often too hot or too cold (or when atmospheric pressure is too low) for water to be found in a liquid state, you’d expect there to be some excitement. When that other planet is Mars, the focal point of the search for basic extraterrestrial life, this excitement will be tempered with intense scrutiny.

In February’s article, Nilton Renno from the University of Michigan and Phoenix mission team scientist, announced results from his team’s research into some odd-looking blobs on one of the lander’s legs. Renno’s hypothesis, to be presented on March 23rd at the Lunar and Planetary Science Conference in Houston (TX), focuses on the possibility that the newly discovered toxic compound, perchlorate, may hold the key to the possibility of liquid water on the Martian surface. We know on Earth, briny (salty) water has a lower freezing point than pure water, and Renno suspects that this might be the case for water on the surface of Mars. However, rather than regular salt, the toxic perchlorate salt is mixed with water in the regolith, allowing it to sustain its liquid state.

Although a very interesting proposition, Renno’s results are based on only photographic evidence of what appears to be blobs of water. Other Phoenix scientists are emphasising that the theory is controversial, citing far simpler answers for the observations.

“There’s a matter of belief at some level,” said Peter Smith from the University of Arizona in Tucson and principal Phoenix investigator. “I can’t say I agree with every statement in the [Renno] paper.”

Michael Hecht, the lead scientist for the instrument that discovered perchlorate in the first place, goes as far to say a perchlorate brine on the Martian surface is very unlikely. Simpler explanations for the apparent dynamic movement of the “liquid” blobs could be attributed to changing shadows. Although perchlorate acts as an efficient “sponge”, condensing water vapour from the surrounding air, the temperatures stated in the paper are actually too warm to form liquid droplets of perchlorate brine.

“I just don’t think it’s the likely explanation,” Hecht said. “It’s just plain old frost, nothing more.”

Looking at the Phoenix images (top), I am a little suspicious about the lifetime of these proposed “liquid” droplets. From sol 8 to sol 44, there is little dramatic change in the locations or sizes of these features. 36 sols of long-term droplets of liquid water seems like a very long time considering the very low atmospheric pressures we are dealing with. Surely liquid brine droplets will dissipate (through evaporation, rather than sublimation) far quicker than 36 sols? Granted, there may be further condensation from the atmosphere (topping up the presence of the liquid), but wouldn’t there be more motion in the blobs if this were the case? This said, I am not familiar with perchlorate brine, so this might well be a characteristic of this cold liquid.

It looks like Renno’s research will make for a very interesting presentation on March 23rd at the Lunar and Planetary Science Conference, sure to provoke a lively debate…

Source: Space.com

March 5, 2009December 24, 2015 by Ian O'Neill

Life on Ceres: Could the Dwarf Planet be the Root of Panspermia?

Ceres as seen by the Hubble Space Telescope in 2004 (HST)

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It has been theorised for a long time that the dwarf planet Ceres may be harbouring a lot of water. With the promise of water comes the hope that life may be present on this little world orbiting the Sun in the asteroid belt. You may be forgiven in thinking that the search for life in the Solar System has gone a little crazy, after all, we haven’t found life anywhere else apart from our own planet. However, if we do discover life on other planetary bodies apart from Earth, perhaps the panspermia hypothesis is more than just an academic curiosity. So why is Ceres suddenly so interesting? Firstly, it probably has water. Secondly, the ex-asteroid is so small that fragments of Ceres could have been kicked into space by meteorite impacts more readily than other larger planetary bodies, making it a prime candidate for seeding life on Earth…

Now THAT is a dw<span>arf plan</span>et: The size comparison of the Earth, Moon and Ceres (NASA) — Now THAT is a dwarf planet: The size comparison of the Earth, Moon and Ceres (NASA)

There’s always good news to outweigh the bad. In 2006 when the International Astronomical Union (IAU) demoted Pluto from being a “planet” to a “dwarf planet”, Ceres had the reversal in fortune in that it was promoted from being just another big asteroid to a dwarf planet. Now this tiny world has become a little more important.

In 2007, NASA launched the Dawn spacecraft that will reach this mysterious dwarf planet in 2015. It will be the first mission to this region of the Solar System, and it is making good progress (Dawn just completed a gravitational flyby of Mars). So far, since its discovery in 1801 by Giuseppe Piazzi, we have only managed to attain some fuzzy images of Ceres using the Hubble Space Telescope (pictured top). As can be seen from the size comparison, trying to spot Ceres is quite a task, it is tiny (in fact, it is the smallest classified dwarf planet out there, so far). This may be the case, but it is its low mass that has excited a University of Giessen (Germany) researcher who is studying the possibility that Ceres could support life.

Although it is unknown whether or not Ceres has liquid water oceans, Joop Houtkooper believes that if it does, basic life forms may be thriving around hydrothermal vents in the hypothetical Ceres oceans. However, it is not clear how these proposed oceans can stay in a liquid state, as it seems unlikely there is significant tectonic activity (as it has very little mass to sustain a long-term molten core) and it is not orbiting a tidally disruptive body (like the icy moon Europa around Jupiter – extreme tidal forces maintain sub-surface oceans in a warm state). However, the idea remains as Ceres has a lower escape velocity than any other planetary body, meaning that microbes (hitch-hiking on fragments of Ceres) could have been kicked into space with more regularity than other planets, such as Mars.

“I looked at the different solar system bodies which either had or currently have oceans,” Houtkooper explains. “The planet Venus probably had an ocean early in its history, but the planet’s greater mass means that more force is needed to chip off a piece of the planetary crust and propel it in the direction of the Earth. Smaller objects like Ceres have lower escape velocities, making it easier for parts of it to be separated.”

Artist impression of the Dawn spacecraft exploring the asteroid belt (NASA)

Also, Ceres appears to have gotten off fairly lightly during the Late Heavy Bombardment, allowing it to retain its surface water. If the Earth had any life before this era, it is possible that the violent impacts sterilized the planet. In this case, it is possible life arrived to Earth via a shard of another planetary body in the form of a meteorite.

Although calculations suggest Ceres could be a very likely candidate as the source of panspermia, eventually leading to life on Earth, the question as to whether Ceres is even a hospitable place for life to form is doubtful. Also, if Ceres was saved from the worst impacts during the Late Heavy Bombardment, and it appears to have retained the majority of its water through lack of impacts, surely Ceres fragments would be a very rare meteorite component?

Still, it is an engrossing area of research, but we’ll have to wait until Dawn arrives in Ceres orbit in a little over five years time before we arrive at any answers…

Source: Space.com

March 5, 2009December 24, 2015 by Ian O'Neill

A Bizarre View From HiRISE: The Melting Volcano

What is it? Strange melt areas on an ancient volcano in the Hellas impact basin (NASA/HiRISE/Univ. of Arizona)

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This image is probably more suited to Nancy’s “Where In The Universe” series, but judging by the resolution and surrounding landscape, it may be fairly easy to distinguish which planet and what instrument took the shot. Of course, this is Mars and the image was snapped by the astounding HiRISE instrument on board the Mars Reconnaissance Orbiter (MRO). Still… what is it? Apart from looking like a particularly large coffee stain, the answer might not be very obvious. However, once we realise this is an image of an ancient volcano covered with ice, the big question is, why has the ice melted in discrete patches when the rest of the landscape looks like a winter wonderland?

On January 16th, the MRO dashed above the southern hemisphere of Mars, over the famous Hellas impact basin. This large crater is very interesting for many reasons, particularly as the altitude distance from the crater rim to the deepest part of the crater bottom is 9 km. This means there is a 89% increase in atmospheric pressure at the bottom of the crater when compared to the planet average. The pressure is therefore high enough to entertain the thought that liquid water may be a reality in this region (if the temperature gets higher than 0°C that is).

There are also ancient volcanoes in the region, of particular note is the group of volcanoes called Malea Patera (as captured in the HiRISE image above). As Hellas is so close to the southern arctic (antarctic?) region, it is currently entering spring time, surface ice is beginning to melt as the Sun creeps higher above the Martian horizon. However, there appears to be areas of ice that are melting faster than others, and a pattern is emerging.

Detail of the melting ice on Malea Patera (NASA/HiRISE/Univ. of Arizona)

At first, I looked at the images and thought that there may be some heat being released from thermal vents in the volcanic region. However, HiRISE scientists have another explanation for the dalmatian spots that have appeared. On Earth, we will often find dark rocks that appear to have melted the snow from around them during a sunny day. This is because the sunlight will penetrate the snow and heat up the darker rocks quicker than the lighter rocks. Dark rocks will absorb solar energy faster than the more reflective light rock, dark rocks heat up faster, snow surrounding dark rocks melts quicker.

This basic ice melting mechanism is being singled out for what HiRISE is seeing on this ancient volcanic region. There are patches of dark rock melting the snow faster than the rest of the region as the Sun gradually heats the southern hemisphere. What is very interesting is the patches and shape of the melt region. Could it be an ancient lava outflow from a volcano? Are the patches sand dunes peppered with volcanic material? Or is there some other explanation? HiRISE scientists hope to take more images of Malea Patera as the seasons roll on to see how the ice continues to melt. It will be interesting to see what HiRISE finds under the ice during the summer…

Source: HiRISE

March 5, 2009December 24, 2015 by Ian O'Neill

Opportunity, the Dune Buggy: HiRISE Watches the Rover’s Trek

Mars Exploration Rover Opportunity trundles over the dunes (NASA/HiRISE/Univ. of Arizona)

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Its pictures like these that put the Mars Program into perspective for me. We have two operational rovers that have rolled across the Martian landscape for five years (when they were designed to last only three months), and we have three satellites orbiting Mars carrying out a variety of key scientific studies. For one of the instruments orbiting over 250 km (155 miles) above the Red Planet on board the Mars Reconnaissance Orbiter (MRO), it is fulfilling the “reconnaissance” duties of the MRO rather nicely. The High Resolution Imaging Science Experiment (HiRISE) is helping out its roving buddy, Opportunity, to plot the best route through the undulating sandy dunes of Meridiani Planum. Robots helping other robots on Mars…

We’ve seen shots like this before taken by the high resolution camera used by HiRISE. From spotting the Phoenix Mars Lander repeatedly throughout 2008 to keeping a watchful eye on the progress of both rovers, the instrument has been an invaluable tool for NASA scientists to see what the landscape is like around the tough wheeled robots.

As another sol rolls on, MER Opportunity clocks up some more distance on its epic two year journey toward Endeavour, a crater 20 times larger than Opportunity’s previous crater subject, Victoria (now a feature shrinking in the rover’s rear view mirror). The rover has a long way to go, but should Opportunity survive the trip, it will be a momentous achievement. After all, the rover will be seven years old at that point.

A close-up of Opportunity, plus wheel tracks (NASA/HiRISE/Univ. of Arizona)

For now, HiRISE is aiding the planning of Opportunity’s drive through the open Mars desert. As can be seen in the HiRISE image to the left (detail from the main image, top), 1783 sols into its mission, the rover is still going strong. The day before this image, Opportunity had driven 130 metres over the sand dunes. Generally, these dunes are mere ripples in the regolith, but some can be too big for Opportunity to traverse. However, HiRISE will spot any hazard well in advance, and NASA can plan Opportunity’s route accordingly.

So Opportunity roves on toward the southeast target of the Endeavour crater, about 17 km away. But HiRISE will be watching…

Source: HiRISE

March 1, 2009April 26, 2016 by Ian O'Neill

Russia Will Send Life to Phobos

Going where no tardigrade has been before

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How ironic. Not content with searching for life on Mars, the Russian space agency and the US-based Planetary Society will soon be sending terrestrial life to the Martian moon Phobos. The mini-interplanetary travellers will consist of bacteria, spores, seeds, crustaceans, insects and fungi. Why? To see how biological life, in various forms, deals with space travel spanning three years.

So if you thought that a human (or monkey) would be the first of Earth’s ambassadors to land on Mars or one of its moons, you’d be very mistaken…

The Phobos-Grunt mission profile

Russia has been carrying out a variety of biological space tests to see how life deals with the hazards of spaceflight recently. In one experiment carried out in collaboration with Japanese scientists, a mosquito was attached to the hull of the International Space Station (ISS) to see… what would happen.

The mosquito was a part of the Biorisk project, and the scientists knew the insect had the ability to drop into a “suspended animation” during times of draught in Africa. The African mosquito can turn its bodily water into tricallosa sugar, slowing its functions nearly to a stop. When the rain returns, the crystallised creature is rehydrated and it can carry on its lifecycle. The Biorisk mosquito however survived 18 months with no sustenance, exposed to temperatures ranging from -150°C to +60°C. When returned to Earth, Russian scientists gave the hardy mozzie a health check, declaring:

“We brought him back to Earth. He is alive, and his feet are moving.” — Anatoly Grigoryev, Vice President of the Russian Academy of Sciences.

Quite happy with living in space, the mosquito ©Gerald Yuvallos/Flickr

Was this insect cruelty of the most extreme kind, or did it serve a purpose? Actually, the mosquito experiment provided an insight to a biological specimen after being exposed to cosmic rays for long periods, and it also showed us that the African mosquito’s natural ability to slip into a defensive coma, only to be revived and appear to be healthy (that is, if it was more than just its feet moving – there was no indication as to whether the little guy was successfully re-integrated into mosquito society). Perhaps the lessons learned from this small test may go to some way of helping us realise the potential for putting future interplanetary astronauts into some kind of biological stasis.

So that’s the idea behind sending creatures into space: we need to understand how animals and plants deal with space travel. This will aid the understanding of how humans will cope in space for long periods, plus we need to understand if there are any harmful effects from growing foodstuffs away from our planet. This is why the Russian space agency wants to go one step further when it launches its Phobos-Grunt mission next year, to send biological specimens on a voyage of a lifetime. A return trip to the Martian moon Phobos.

Say hello to our interplanetary ambassador, the tardigrade (FUNCRYPTA)

On board, it is hoped the US-based Planetary Society will be able to send a small package filled with 10 different species including tardigrades (“water bears”), seeds and bacteria. The main purpose of this experiment will be to test the panspermia hypothesis, where it is thought that life may travel from planet to planet, hitching a ride on fragments of planetary material. Most of the biological samples will be in a dormant state (i.e. the plant spores), and tests will be carried out when Phobos-Grunt returns to Earth to see if the bacteria survived, seeds germinate and spores… do what ever spores do.

Russia on the other hand has far loftier goals; the space agency will attach a small petting zoo. Inside the Russian experiment will include crustaceans, mosquito larvae (already proven to be enthusiastic space travellers), bacteria and fungi. The Russian experiment will specifically look at how cosmic radiation can effect these different types of life during an interplanetary trip (essential ahead of any manned attempt to the Red Planet).

Naturally, there are some concerns about contamination to the moon (if Phobos-Grunt doesn’t do the “return” part of the mission), but the chances of any extraterrestrial life being harboured on this tiny piece of airless rock are low. Having said that, we just don’t know, so the mission scientists will have to be very careful to ensure containment. Besides, there’s something unsettling about infecting an alien world with our bacteria before we’ve even had the chance to get there ourselves…

Source: Discovery

March 1, 2009December 24, 2015 by Ian O'Neill

Is There a Mysterious Black Hole Constant?

Space-time warping as a small black hole orbits a larger black hole (Don Davis)

[/caption]If you found yourself in the unfortunate situation of orbiting a black hole, you may be in for a rather dizzying and unpredictable ride. If the black hole is spinning, it will flatten out under centrifugal forces, much like the Earth bulges slightly at the equator, but the black hole’s bulge will be radically greater. As the shape of the black hole changes, so does its gravitational profile.

As you are not orbiting a spherical black hole, you can no longer expect to have a boring, predictable orbit; your orbit will become wild and chaotic, seemingly random. However, it would appear that there is an underlying constant to the mayhem, and what’s more, it seems this constant has also been observed in a more pedestrian system: a three-body Newtonian system. So what’s the link? Physicists aren’t quite sure…

When a massive star exhausts its fuel, it may collapse in on itself to create a black hole (after some exciting supernova action). The angular momentum of the original star is expected to be preserved, producing a rapidly spinning black hole. If the black hole “has no hair” (i.e. it has no electrical charge), the gravitational field solely depends on its mass and spin. If there is deformation due to the spin, the gravitational field changes, sending any orbiting body (like a neutron star) on a crazy roller-coaster ride.

In a new paper by Clifford Will of Washington University in St. Louis, the excited physicist describes the scenario. “The orbits go wild — they gyrate and spin, they’re incredibly complex. It’s fantastic,” Will says.

However, physicist Brandon Carter discovered a mathematical constant back in 1968, showing these apparently chaotic orbits are predictable, and that it even applies to orbits around extremely warped space-time. “Black holes have this extra constant that restores the regularity of the orbits,” comments Saul Teukolsky of Cornell University. “It’s a mystery. Every other situation where we have these extra constants, we have symmetry. But there’s no symmetry for an orbiting black hole — that’s why it is regarded as a miracle.”

Quite simply, physicists have no idea why the Carter constant could arise from the General Relativity description of a spinning black hole. Now, to make the problem even more perplexing, Will carried out a classical (Newtonian) 2-body simulation with a third body orbiting. Again, the same constant appeared. It would appear that there is something special about the predictability of an orbit around this black hole configuration.

Teukolsky, who worked on similar problems for his Ph.D. in 1970, remains baffled by these results. However, Will continues to investigate the problem, by including a term for black hole frame dragging. In this situation, the spinning black hole will drag space-time around it, “creases” (or ripples) in space time being pulled with the direction of spin. In this case, the Carter constant disappears, only to return when higher order terms are added to the equations.

This all means one of two things. Either it is simply an artefact in the mathematics, a curiosity that will eventually be rooted out of the equations. However, there is a tantalising possibility that we are seeing a characteristic of exotic rotating black holes, where the configuration of the surrounding fabric of space-time can allow a predictable orbit to come out of the apparent chaos…

Source: Science News

Here’s an article about black body radiation.

February 28, 2009December 24, 2015 by Ian O'Neill

New Technique Allows Astronomers to Discover Exoplanets in Old Hubble Images

Using a new imaging technique on an 11 year old Hubble observation, an exoplanet has been discovered orbiting the young star HR 8799 (NASA/HST)

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The Hubble Space Telescope has recently provided us with some astonishing images of exoplanets orbiting distant stars. This is a departure from the indirect detection of exoplanets by measuring the “wobble” of stars (revealing the gravitational presence of a massive planetary body) or the transit of exoplanets through the line of sight of the parent star (causing its brightness to dim). Scientists have refined Hubble’s exoplanet hunting abilities to directly image these alien worlds in visible light. However, astronomers now have another trick to find these mysterious worlds. A new imaging technique is allowing us to see exoplanets already hiding in archival Hubble data…

It has been estimated that another 100 previously unknown exoplanets could be discovered in old Hubble data. The technique being tested by astronomers at the University of Toronto could be a very powerful new way to reveal the existence of a huge number of buried jewels buried by the glare of star light.

In November 2008, a spate of direct imagery of exoplanets showed the world how advanced our ground and space-based observatories were becoming. One such discovery was an observing campaign of the young star HR 8799 by the near-infrared adaptive optics observations of the Gemini and Keck telescopes. HR 8799 (140 light years away, approximately 50% more massive than our Sun) plays host to three massive gas giants (10, 10 and 7 times the size of Jupiter). Now that HR 8799 is known to have large exoplanets orbiting around it, the University of Toronto astronomers, headed by David Lafrenière, have re-examined images taken by Hubble of that same star in 1998, to see if there is any trace of these exoplanets in the old data. In 1998, HR 8799 appeared to be a lonely star, with no associated exoplanets.

Using a new technique to extract the weak exoplanet emission in the Hubble image, Lafrenière’s team have been able to cut down the glare of the parent star to reveal the presence of the outermost exoplanet of the trio known to be orbiting HR 8799 (pictured top). The other two exoplanets remain too close to the star to be resolved.

The University of Toronto result “definitely indicates that we should reanalyze all the existing Hubble images of young stars with the new approach — there’s probably 100 to 200 stars where planets could be seen,” comments planet-hunter Bruce Macintosh of the Lawrence Livermore National Laboratory in California. Many of these stars have already been studied by the powerful Keck observatory in Hawaii, so astronomers now have an exciting and powerful new analysis tool to hopefully reveal more overlooked exoplanets.

However, this most recent result was achieved by using a space-based observatory, as some of the near-infrared emission from the exoplanet will be absorbed by the Earth’s atmosphere.

The new exoplanet discovery potential has excited many astronomers, and it has highlighted the importance of maintaining a good archive of astronomical observations. “The first thing it tells you is how valuable maintaining long-term archives can be. Here is a major discovery that’s been lurking in the data for about 10 years!” said Matt Mountain, director of the Space Telescope Science Institute in Baltimore. “The second thing its tells you is having a well calibrated archive is necessary but not sufficient to make breakthroughs — it also takes a very innovative group of people to develop very smart extraction routines that can get rid of all the artifacts to reveal the planet hidden under all that telescope and detector structure.”

Hopefully we’ll be seeing even more exoplanet discoveries over the coming months, not just from new observing campaigns, but possibly from old observations using archived observatory data. Exciting times!

Source: Science News

February 28, 2009April 26, 2016 by Ian O'Neill

Could a Second Ares I-X Test Flight Close the 5-Year Gap?

Artist impression of the Ares I-X at the launchpad, plus labelled sections of the rocket (NASA)

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Approximately $400 million extra has become available for NASA manned space flight and managers are currently discussing the possibility of using it toward a second test flight of the Ares I-X. The first test flight of the next generation launch vehicle is planned for a summer 2009 launch, and with this extra funding comes the possibility of a second test flight dubbed “Ares I-X prime”. In a renewed vigour for getting the US back to the Moon by 2020, and the looming “5-year gap”, it appears the extra funding may allow NASA to hasten the development of the Constellation Program…

So it turns out the economic stimulus package will affect the development of NASA’s Constellation Program after all, possibly speeding it up. Of growing concern is the fact that it is looking very likely (according to the White House budget blueprint) that the shuttle will be retired as planned in 2010, leaving five long years until the planned 2015 completion of the Constellation Program. This 5-year gap has spawned all kinds of political problems (i.e. depending on the Russian space agency to get US astronauts to the International Space Station), but it has also stimulated investment in private space launch companies.

Although details are still being worked out on how the extra money will be distributed, it is hoped that the $1 billion allocated to NASA from the stimulus package may “save or preserve 7,000 jobs”. The money invested in manned spaceflight could also speed up technological advancement, possibly speeding Constellation progress. Managers hope an extra test-flight of the Ares I-X could also be used to hasten development of prototype flight systems. Doug Cooke, associate administrator for exploration systems, confirmed that to use this extra funding for a second test flight “certainly is within the realm of possibility.”

By laying on a second test flight after the Ares I-X scheduled for this summer, Ares I-X prime could substantially accelerate progress, possibly reducing the 5-year gap by as much as a year. The second flight of the Ares I-X would test the five-segment version of the four-segment solid fuel shuttle booster that will act as the first stage of the Ares I. The solid fuel launch abort system would also be tested at high altitude.

Source: Aviation Week

February 28, 2009December 24, 2015 by Ian O'Neill

Powerful Fusion Laser to Recreate Conditions Inside Exoplanets

A powerful laser could create the conditions inside a giant exoplanet (Sunbeamtech)

[/caption]We’ve all heard that the Large Hadron Collider (LHC) will collide particles together at previously unimaginable energies. In doing so, the LHC will recreate the conditions immediately after the Big Bang, thereby allowing us to catch a glimpse of what particles the Universe would have been filled with at this time. In a way, the LHC will be a particle time machine, allowing us to see the high energy conditions last seen immediately after the Big Bang, 13.7 billion years ago.

So, if we wanted to understand the conditions inside a giant exoplanet, how could we do it? We can’t directly measure it ourselves, we have to create a laboratory experiment that could recreate the conditions in the core of one of these huge exoplanet gas giants. Much like the LHC will recreate the conditions of the Big Bang, a powerful laser intended to kick-start fusion reactions will be used in an effort to help scientists have a very brief look into the cores of these distant worlds…

The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory in California is ready for action. The facility will perform fusion experiments, hopefully making a self-sustaining nuclear fusion reaction a reality using an incredibly powerful laser (firing at a hydrogen isotope fuel). Apart from the possibility of finding a way to kick-start a viable fusion energy source (other laboratories have tried, but only sustained fusion for an instant before fizzing out), the results from the laser tests will aid the management of the US nuclear weapon stockpile (since there have been no nuclear warhead tests in 15 years, data from the experiments may help the military deduce whether or not their bombs still work).

Fusion energy and nuclear bombs to one side, there is another use for the laser. It could be used to recreate the crushing pressures inside a massive exoplanet so we can glean a better understanding of what happens to matter at these crushing depths.

The NIF laser can deliver 500 trillion watts in a 20-nanosecond burst, which may not sound very long, but the energy delivered is immense. Raymond Jeanloz, an astronomer at the University of California, Berkeley, will have the exciting task of using the laser, aiming it at a small iron sample (800 micrometres in diameter), allowing him to generate a moment where pressures exceed a billion times atmospheric pressure. That’s 1000 times the pressure of the centre of the Earth.

On firing the laser, the heat will vaporize the iron, blasting a jet of gas so powerful, it will send a shock wave through the metal. The resulting compression is what will be observed and measured, revealing how the metal’s crystalline structure and melting point change at these pressures. The results from these tests will hopefully shed some light on the formation of the hundreds of massive exoplanets discovered in the last two decades.

“The chemistry of these planets is completely unexplored,” says Jeanloz. “It’s never been accessible in the laboratory before.”

Now that is one impressive laboratory experiment…

Source: New Scientist

February 27, 2009April 26, 2016 by Ian O'Neill

Obama Will Retire Shuttle in 2010, US Will Go Back to the Moon in 2020

[/caption]In a budget blueprint released by the White House on Thursday, President Barack Obama has confirmed his intent to carry out the planned retirement of the ageing Space Shuttle next year. Additionally, the the blueprint affirms Obama’s stance on a return trip to the Moon. The US will return to the lunar surface by the year 2020, following the time scale set out by George W. Bush’s 2004 Vision for Space Exploration. However, there is no mention that the next manned lunar mission will be carried out by the Constellation Program, a project plagued by criticism about its design and technology.

Although the blueprint may differ from the final budget submitted to Congress in April, it looks like there is some certainty about the future of the shuttle and the direction NASA will be taking over the next decade. And now the space agency has a little bit more money to do something about that troublesome 5-year gap in US manned access to space…

So, any hope to extend the life of the Shuttle looks to have been dashed. Although there could still be a chance for a shuttle extension when the final budget is submitted, it seems as if President Obama has made his intent very clear; the 25 year-old space launch system will be mothballed, as planned, in 2010. This may come as a relief to many as extending the operational lifetime of the shuttle could be a safety risk, however, many on Florida’s Space Coast won’t be so happy as they could be looking at losing their jobs sooner than they would have hoped.

Generally, these decisions have been welcomed, including the extra $2.4 billion NASA will receive for the 2010 fiscal year (when compared with 2008):

Combined with $1 billion provided to NASA in the $787 billion stimulus package signed into law Feb. 17, the agency would receive $2 billion more than in the $17.7 billion 2009 NASA budget that was passed by the House – an increase that equals an Obama campaign promise. — Florida Today

It remains uncertain how the gap between shuttle retirement and Constellation launch could be shortened from the minimum of five years, but the extra cash is bound to boost confidence. But where does the blueprint say Constellation is even part of the plan? It doesn’t, sparking some media sources to point out that it remains a possibility that the Ares rocket system could be abandoned in favour of making the existing Atlas V or Delta IV rockets human rated. However, space policy specialists are advising not to read too much into the omission.

“The budget doesn’t say a whole lot about any specific system,” said John Logsdon, a space policy analyst at the National Air and Space Museum in Washington, DC. “I wouldn’t interpret the absence of the words ‘Constellation’, ‘Ares’, and ‘Orion’ one way or another. That’s really up to the the new management team, when it gets there.”

After all, since the departure of Michael Griffin as NASA Administrator, the space agency has been without a leader. Acting NASA Administrator Christopher Scolese is currently at the helm, saying that the new budget “is fiscally responsible and reflects the administration’s desire for a robust and innovative agency.” Unfortunately the details about the use of Constellation may remain sketchy until the final budget is submitted.

This may be the case, but President Obama has obviously seen the merit in the original plans to get man back to the Moon by the year 2020, despite criticism from a guy who has actually stood on the Moon, Buzz Aldrin. In an “alternative” proposal for the future of NASA, Aldrin and two co-authors posted a draft of the “Unified Space Vision” on the National Space Society’s website this week (Update: the draft has now been “Removed At Request of the Authors”), urging the administration not to mount an unnecessary lunar mission (been there, done that) and go straight for manned exploration of the asteroids and Mars. The Unified Space Vision, unfortunately, was probably too hard on NASA’s accomplishments, saying that “post-Apollo NASA” has become a “visionless jobs-providing enterprise that achieves little or nothing,” in developing a viable space transportation system. Many of the points raised are valid (and occasionally very tough), but would require a complete change in NASA’s structure to accomplish. I doubt we’ll see any radical changes being enacted any time soon.

So, we now have a pretty good idea as to what’s going to happen to the shuttle next year; it looks like the plan to get the US back to the Moon by 2020 is still on and NASA has been given an extra $2 billion to play with. I hope they spend it wisely, perhaps on private space launch contracts?

Sources: Florida Today, New Scientist