minerals on asteriods?

Last Tuesday, the future finally sounded like the future. A coalition of willing billionaires, spaceflight professionals, and scientific advisors under the banner of Planetary Resources announced their deadly serious intention to go out there and mine themselves some asteroids (video). And the scientific community responded with a heartfelt finally. Assuming this plan isn’t the prelude to some kind of Bond-villian-esque scheme to hold the world hostage for trillions of dollars or they’ll drop an asteroid on our heads (note to self: screenplay??), what’s going to happen? What does it mean for astronomers and planetary scientists? What contributions will the scientific community make, and what data do we stand to gain?

Fragments from the recent meteorite fall over California and Nevada, which has been identified as a rare carbonaceous chondrite. Though they make up a small percentage of falls, carbonaceous chondrite asteroids are abundant in space. (Image credit: Image Credit P. Jenniskens (SETI Institute) and Eric James (NASA Ames))

Asteroids are not just little floating gold mines, they’re precious scientific relics. They are the only nearby remnants of the presolar nebula, and preserve a vast trove of data about the cloud of gas and dust that formed our Sun and Solar System, the processes that built up the planets, and even fragments of what came before. Asteroids can provide vital insights into theories of planet formation by telling us about disk composition and temperature. They preserve the history of the processes that built them up, telling us about how dust and rock clump together to form larger bodies, a subject of great interest to those who study extrasolar planets. They’re also the best source for the composition of the presolar nebula, and by extension provide one of the benchmarks for the solar abundance set, or the relative abundances of the chemical elements, key to our understanding of nucleosynthesis and related topics. Right now, however, our only access to asteroids is via meteorites (ah, astronomy; where waiting for research material to fall out of the sky is a viable strategy). Meteorites are often found after sitting on the surface for a long time, enduring Earth’s many chemical processes. This destroys any volatiles that may have been retained, and introduces contamination. And they’re quite rare. In particular the CI carbonaceous chondrite group, upon which the solar abundance set is benchmarked, is very rare; the majority of our data comes from 12 pounds of rock in a jar in France.
So astronomers and planetary scientists would love to get their hands on tons of pristine space rock. Why haven’t we done it yet? Mining asteroids – or at least returning samples from them – has long been a staple not just of science fiction, but of decadal surveys and mission concepts. NASA, JPL, and even some private firms have studied mission concepts for sample returns and rendezvous with asteroids for a long time. But only a few targeted missions have been launched, such as the Dawn spacecraft currently studying the asteroid Vesta and the Japanese Hayabusa spacecraft, which successfully returned 1500 grains of material from the Near-Earth asteroid 25143 Itokawa. Other spacecraft such as Deep Space 1 and Galileo have swung by asteroids on their way to other destinations, but done little more than photograph the objects in passing.  And NASA’s planetary science budget has suffered greatly in recent years as the agency struggles to keep JWST alive in the face of Congressional budget cuts.

The giant asteroid Vesta, as imaged by the Dawn spacecraft. (Image credit: Image Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA).

Recently, however, interest has been growing in Near-Earth Asteroids (NEAs) not just as potential scientific targets or potential hazards, but as stepping stones for revitalizing the space exploration program. After the Moon, Near-Earth Asteroids are the closest bodies to Earth that could be the target of human missions. The Augustine Report, which set out to chart the future of NASA’s human spaceflight plans, recommended asteroid exploration as the next phase of manned missions, and the White House endorsed the idea. Several mission concepts have been offered up, some manned and some robotic. But so far no firm plans have been made. Until now. Planetary Resources, whose headliners include Larry Page and Eric Schmidt from Google, director James Cameron, Peter Diamandis from the X-PRIZE foundation, Chris Lewicki of Spirit and Opportunity fame, and Dr. Sara Seager from MIT (seriously guys, Bond movie plot), have decided to take matters into their own hands.
How are these guys different from any other pie-in-the-sky startup dreaming of a huge payoff? All of us have heard grandiose claims about the future of space exploration before. How do we know we’re not going to get our hearts broken again? Well, the ideas they’ve put forward, the team they’ve assembled, and the resources this group can bring to bear are remarkable enough for everyone to give them a second look. Just the fact that they have a plan rather than simply making a grand proclamation is a good sign.
Planetary Resources’ mining strategy as currently described comprises four stages: survey, using cheap robotic telescopes to catalogue NEAs; reconnaissance, using small satellites to fly past asteroids passing close to Earth; assessment, sending robotic spacecraft to study potential targets; and mining proper, when the resources are finally extracted. Let’s break it down step by step. If you’d like to watch some videos on the subject, by the way, the company has posted several on their Youtube channel.

The Leo telescope, aka Arkyd 100 series. A small, cheap telescope meant to survey for NEAs. (Image credit: Planetary Resources).

Survey: The first stage of the Planetary Resources plan is simply to launch a fleet of robotic telescopes into low Earth orbit (LEO) expressly for the cataloguing of asteroids. Although NASA’s Spaceguard program has catalogued about 93 percent of the large (> 1km) NEAs, there are still plenty of mid-size and smaller objects to be found. Because NEAs are small, dark objects, it’s hard to find them. New objects are being discovered all the time, and a fleet of telescopes that do nothing but look for them can only be good for astronomers. The Planetary Resources plan describes a small satellite called “Leo” mounting a telescope with arcsecond resolution. Their description also implies that time on the Leo telescopes may be publicly available for purchase, which could be interesting. No word on what band these telescopes operate in, but if they’re smart, they’ll put at least a few in the mid- to far-infrared – as this article describes, far-infrared telescopes are better at finding asteroids because they can see their thermal emission rather than just searching for reflected sunlight.
Feasibility:. According to Phil Plait, the Leo telescopes will have a mirror diameter of 9″, quite sufficient to give arcsecond resolution, and an overall satellite size of 16″. This miniscule form factor is absolutely vital; the single biggest line-item in any small satellite project is far and away the launch, so Planetary Resources is going to take advantage of so-called “secondary payloads,” smaller cargo carried to fill out a rocket that’s hauling a much larger satellite. In order to take advantage of these piggyback rides into space, however, the Leos must be small enough to pack into a payload shroud without disturbing the prime cargo. I’d guesstimate their overall weight in the realm of 50 – 75 kg, within the standard limits for ESPA ring launches (one image on the website even shows what looks like an ESPA ring connector plate attached). Eyeballing the graphics on the website, it looks like the Leo satellites have a system of cold-gas thrusters for pointing, probably coupled with a set of small reaction wheels. They have a single small solar panel that likely doubles as a sunshield for cooling the camera and the electronics, and possibly a couple of star trackers for orientation and navigation. It’s a fairly standard small satellite design and eminently feasible. Order-of-magnitude I’d guess each bird will cost in the neighborhood of $1-2 mil in parts and labor.
Planetary Resources says they’re going to launch several of these, which could be a costly endeavor, and that they’re making them in-house – that, in fact, they’ve already started. Making them in bulk will make things easier – if one fails, just iterate on the next one – but regardless of how off-the-shelf the technology may seem, putting anything in space is never an easy or routine operation. Still, this is something that has been done before.

The Interceptor spacecraft, planned to perform flybys of NEAs crossing through the Earth-Moon system. (Image credit: Planetary Resources).

Reconnaissance: The second phase described by Planetary Resources involves fitting out a couple of the Leo telescopes with rocket motors and slinging them up past geosync to flyby asteroids passing through the Earth-Moon system. A surprising number of NEAs pass between the Earth and the Moon, and a disturbing portion of them are only spotted during near-misses with Earth. Presumably the Leo network from the first phase will come into play here, spotting a flyby candidate in time for a rendezvous to be arranged. These “Interceptor” missions will try to hitch a ride with satellites heading not to the relatively nearby confines of LEO, but the distant reaches of geosynchronous orbit (GEO), about 40,000 km out; from there it only takes a relatively small additional boost to push themselves far away from Earth. These satellites would study passing asteroids much more closely, and with a wider suite of scientific instruments. There’s even a mention of a possible sample return from one of these flybys, a prospect that should make all astronomers giddy.
Feasibility: Hitching a ride to geosynchronous orbit is a trickier proposition. Boosting an object up to geosynchronous orbit takes a lot more energy than low Earth orbit, so a rocket that can put N tons into LEO can only put a small fraction of that into GEO. That means payload space is much tighter heading up to GEO, leaving far less room for hitchhikers. The extra poundage of the added scientific instruments and the rocket maneuvering system will also probably beef the Interceptor spacecraft up to 150 – 200 kg. But that’s well within the realm of possibility, and there’s no reason these spacecraft couldn’t get a great look at an asteroid as it cruises by. Sample return may be harder to manage in such a small package.  Hayabusa managed to return a sample, but that spacecraft was purpose-built, and even then only got the sample back by the skin of its teeth.

A fleet of prospecting spacecraft assessing a potential mining target. (Image credit: Planetary Resources).

Assessment: Once we’ve catalogued the NEAs, it’s time to pick out our favorites. The Interceptor satellites already have, in theory, everything they need to operate away from Earth. This phase involves outfitting the satellites with “deep space laser communication technology” and sending them out away from Earth entirely to meet up with the chosen asteroids. There the spacecraft, or more likely the group of spacecraft, will park themselves in a matching orbit and survey the asteroid with all the instruments at their disposal. They’ll be able to collect all the data necessary for a more permanent rendezvous, such as maps of the surface and measurements of rotation rates and density. No word on whether this phase of the mission also has the potential for sample return, but it would be an obvious place to do it. Scientifically this phase is rich. Detailed, up-close data from several asteroids would be great news for a lot of astronomers. Hopefully at this point NASA will also be building their own missions to survey and possibly send manned missions to NEAs, and the synchronization of the two could provide a wealth of fresh data.
Feasibility: Launching satellites into Earth-trailing or Earth-leading orbits has been done many times. Really the unusual part about this phase is the addition of laser communication. Laser communication in space is a new technology that has great promise, but not a lot of proven reliability. Currently, deep space missions use radio communications, so the signal spreads out according to the inverse square law as it travels. This means that spacecraft traveling farther from Earth see nonlinear increases in the amount of power, and therefore size and mass, required to sustain communication. Deep-space missions have data transfer rates that would make the 1980s laugh. Laser communication, by contrast, promises a much more focused signal at lower power. It’s a great innovation and one that has a lot of potential for dropping the cost of deep-space missions. But it’s not entirely a proven technology. The MESSENGER spacecraft was able to signal Earth with an onboard laser during a flyby, and NASA has lofted a Technology Demonstrator Mission to study it, but that’s about it. Laser communication is key to preserving the second phase design without heavy modification, and keeping the size and weight of the satellite down to the level where it can reasonably piggyback on other launches.

A targeted asteroid ready for mining. (Image credit: Planetary Resources).

Mining: After all this exhaustive surveying and assessment, it’s time to reap the rewards. It’s not clear how Planetary Resources plans to actually mine the asteroids. However, they aren’t going to just haul a rock into Earth orbit and start breaking it down for scrap. One of the aims of their mining program is to harvest not just precious metals but volatiles such as oxygen or water that are key to future manned spaceflight missions. Every pound of water or air on a manned mission must be hauled up from the surface of the Earth at a cost of roughly $50,000 per kilogram. Since volatiles captured from an asteroid are already in space, they can be had for a fraction of the cost. I can imagine robotic probes carving ice from an asteroid, to be slung back to the Earth-Moon system and picked up by a manned mission waiting in LEO to fuel up before heading off to parts unknown. A mission to a destination such as Mars might even plan to meet up with asteroid-launched containers of volatiles along the way. Solving the volatile problem would make planning human missions orders of magnitude easier – and cheaper. In the end this might be the most valuable contribution of the program. I’m not going to assess the feasibility of this part, because it’s far enough into the future that who knows what kind of tech we’ll have around.
So there you have it. At first glance, this plan sounds like science fiction. At second glance, it totally is. But that’s okay, because this is the future and if it doesn’t sound like science fiction then you haven’t been paying attention. It is a remarkably well-thought out plan that seems to have some serious engineering backing it up. More importantly, it doesn’t rely on too many unspecified, as-yet-undiscovered technological advances like many other doomed startups. The tech described has largely been invented, and requires only resources and ingenuity to combine into a working program. The slew of backers makes me think this isn’t a group that will give up easily, and they certainly have the resources to pour into it to keep things alive till the big payoff at the end. And what does this mean for us as scientists? If the program gets off the ground, we stand to harvest an incredible trove of data, particularly with planetary science budgets being slashed.

An unusual asteroid trailing a debris tail, likely the result of a collision in the main asteroid belt between Mars and Jupiter. (Image credit: Credit: NASA, ESA, D. Jewitt (UCLA)).

But it’s not clear how science will be incorporated into the program, and that worries me. There are some concerns about the fact that Planetary Resources is a private company. First of all, we don’t know how public the data from their surveys will be. And because their motives are, ultimately, profit, their list of target asteroids may not sync up with a scientist’s priorities. An astronomer interested in the composition of the presolar nebula, for example, will want to investigate the stony carbonaceous chondrite asteroids, which would be of little interest to a miner interested in platinum-group metals. An astronomer might be reluctant to dismantle an asteroid for fear of disturbing potential data, while a miner’s entire plan is to take it apart. Scientific study and resource exploitation can coexist, often quite fruitfully – in this case it will require astronomers to tell the miners where to mine, and miners to get the astronomers their data – but that does not mean the relationship will not be tense at times. This is not a government mission, where scientists can argue for control on the grounds of public benefit; it’s privately-funded and privately-executed, meaning Planetary Resources can act as they will.
Plus, there are legal intricacies to be tackled.  The current treaties governing space and space resources classify asteroids as scientific resources that cannot be used for commercial exploitation.  However, a lot of the treaty language is deliberately vague.  This program isn’t going to plant the first shovel in an asteroid’s surface for several years at the least, so there’s time to work out the law in advance.  But if there is a conflict between the priorities of the scientific community and the commercial concerns, it could get messy.
Despite these concerns, I’m all for it. I think this can work, and I really, really hope it can work.  There is a deeper motive here. In other sciences, the counterpart to a theorist is an “experimentalist.” In astronomy, it’s an “observer.” By and large astronomy is the science of staring at things you know you will never touch. None of us will ever see the objects we study firsthand. Excepting those few lucky scientists working on planetary missions, we will never be able to interact with our subjects. Sometimes it is easy to feel as though the sky itself is just a big globe encircling the Earth, and astronomers are engaged in a thorough study of the wallpaper. When a meteorite falls, a piece of the stars has come to Earth. For one brief moment, we can touch what we have spent our lives watching.
It’s time to stop waiting around for our field to come to us. It’s time for us to go out and find it.

new steamy watery exo-planet!

GJ1214b, shown in this artist’s view, is a super-Earth orbiting a red dwarf star 40 light-years from Earth. Credit: NASA, ESA, and D. Aguilar (Harvard-Smithsonian Center for Astrophysics)

Would Kevin Costner’s character in the movie “Waterworld” be at home on this exoplanet? The planet GJ 1214b was discovered in 2009 and was one of the first planets where an atmosphere was detected. In 2010, scientists were able to measure the atmosphere, finding it likely was composed mainly of water. Now, with infrared spectra taken during transit observations by the Hubble Space Telescope, scientists say this world is even more unique, and that it represents a new class of planet: a waterworld underneath a thick, steamy atmosphere.

“GJ 1214b is like no planet we know of,” said Zachary Berta of the Harvard-Smithsonian Center for Astrophysics (CfA). “A huge fraction of its mass is made up of water.”

GJ 1214b is a super-Earth — smaller than Uranus but larger than Earth — and is about 2.7 times Earth’s diameter. That gives it a volume 20 times as great as Earth yet it has less than seven times as much mass, so it’s actually kind of a lightweight. This world is also hot: it orbits a red-dwarf star every 38 hours at a distance of 2 million kilometers, giving it an estimated temperature of 230 degrees Celsius.

Berta and a team of international astronomers used Hubble’s Wide Field Camera 3 (WFC3) to study GJ 1214b when it crossed in front of its host star. During such a transit, the star’s light is filtered through the planet’s atmosphere, giving clues to the mix of gases.

“We’re using Hubble to measure the infrared color of sunset on this world,”

Hazes are more transparent to infrared light than to visible light, so the Hubble observations help to tell the difference between a steamy and a hazy atmosphere. They found the spectrum of GJ 1214b to be featureless over a wide range of wavelengths, or colors. The atmospheric model most consistent with the Hubble data is a dense atmosphere of water vapor.

Since the planet’s mass and size are known, astronomers can calculate the density, of only about 2 grams per cubic centimetre. Water has a density of 1 gram per cubic centimetre, while Earth’s average density is 5.5 grams per cubic centimetre. This suggests that GJ 1214b has much more water than Earth does, and much less rock.

As a result, the internal structure of GJ 1214b would be extraordinarily different from that of our world.

“The high temperatures and high pressures would form exotic materials like ‘hot ice’ or ‘superfluid water’, substances that are completely alien to our everyday experience,”

Theorists expect that GJ 1214b formed further out from its star, where water ice was plentiful; later the planet migrated inward towards the star. In the process, it would have passed through the star’s habitable zone, where surface temperatures would be similar to Earth’s. How long it lingered there is unknown.

GJ 1214b is located in the constellation of Ophiuchus (The Serpent Bearer), and just 40 light-years from Earth. Scientists say it will be a prime candidate for study by the NASA/ESA/CSA James Webb Space Telescope, planned for launch later this decade.

and so the search for habitable planets continues. There are many planets that have one or two of the requirements for life and as the human race continues to search and enhance our knowledge led by great thinkers and better and better technology, we will undoubtedly find a great many worlds suitable for life after all what a great waste of space it would truly be. of course there is a whole bag of issues we will have to address when that time comes. like what if there is someone or something already living there. of course logistics of even getting that far in time and space. these are just a few of the many problems we will have overcome. Nevertheless we will and must as it is the law of nature for we as a species to evolve and explore. dont forget to follow me on twitter where you can ask questions and make comments!.....@myerlink..............

Read the team’s paper (pdf).

May our earth be running of of crust?

New land creation can be seen in a volcanic crater on Kilauea. (USGS)

Earth just doesn’t make crust like it used to… at least, not according to new research by a team of scientists in the UK.

Researchers with the Universities of Bristol, St Andrews and Portsmouth have studied elements trapped within zircon samples gathered from all over the planet to peer billions of years back in time at how Earth’s crust was being produced.

Zircon, a mineral found in granite, can be dated with precision and is thus an accurate measure for geologic timescales.

What they found was that 65% of our planet’s current crust had already existed 3 billion years ago. Since rocks older than 2.5 billion years are rare on Earth today, this means that some process began to take place that either reworked — or destroyed — a large portion of the older crust, and changed how new crust was formed.

" During the first 1.5 billion years of Earth’s history, the team reports, the rate of crust formation was high — approximately 3 cubic kilometers was added to the continents each year. After that the rate dropped substantially, falling to about 0.8 cubic kilometers per year for the next 3 billion years — right up to the present day."

The cause is yet unknown, but it may be the result of the onset of plate tectonics driven by subduction — the process by which sections of Earth’s crust (“plates”) slide beneath other sections, sinking into the underlying mantle to be liquefied into magma by pressure and heat. New crust is created when the magma rises again where the plates separate… Earth’s current “conveyor belt” of crust formation.

Whatever process was in place prior to 3 billion years ago, it was much more efficient at creating crust.

“Such a sharp decrease in the crustal growth rate about 3 billion years ago indicates a dramatic change in the way the continental crust was generated and preserved,” said Dr. Bruno Dhuime of the University of Bristol’s School of Earth Sciences. “This change may in turn be linked to the onset of subduction-driven plate tectonics and discrete subduction zones as observed at the present day. The next challenge is to determine which tectonic regime shaped the Earth’s crust in the planet’s first 1.5 billion years before this change.”

The team’s paper “A Change in the Geodynamics of Continental Growth 3 Billion Years Ago” (Bruno Dhuime, Chris J. Hawkesworth, Peter A. Cawood, Craig D. Storey) was published March 16 in Science.

Read more on the University of Bristol’s press release here. .......Dont forget to follow me or askme questions or leave corrections or coments to me @myerlink....twitter!!!!

What the matter with dark matter? and energy

So what is this" dark matter" and energy business? well for starters they are polar opposites from each other in the way, that they react to each other and to the universe. First dark matter is actually an element and what scientists believe keeps our galaxies from breaking apart on their high speed travels around the cosmos. Dark energy on the other hand is another mystery for that is believed to be the cause of the effect that the universe is spreading apart at an accelerated rate. This was one of the topics recently touched on by the science Friday show. here are some links and related articles. enjoy! ...........Don't forget to follow me on twitter @myerlink................

Dark Energy, Dark Matter

In the early 1990's, one thing was fairly certain about the expansion of the Universe. It might have enough energy density to stop its expansion and recollapse, it might have so little energy density that it would never stop expanding, but gravity was certain to slow the expansion as time went on. Granted, the slowing had not been observed, but, theoretically, the Universe had to slow. The Universe is full of matter and the attractive force of gravity pulls all matter together. Then came 1998 and the Hubble Space Telescope (HST) observations of very distant supernovae that showed that, a long time ago, the Universe was actually expanding more slowly than it is today. So the expansion of the Universe has not been slowing due to gravity, as everyone thought, it has been accelerating. No one expected this, no one knew how to explain it. But something was causing it.

Eventually theorists came up with three sorts of explanations. Maybe it was a result of a long-discarded version of Einstein's theory of gravity, one that contained what was called a "cosmological constant." Maybe there was some strange kind of energy-fluid that filled space. Maybe there is something wrong with Einstein's theory of gravity and a new theory could include some kind of field that creates this cosmic acceleration. Theorists still don't know what the correct explanation is, but they have given the solution a name. It is called dark energy.

What Is Dark Energy?

Universe Dark Energy-1 Expanding Universe

This diagram reveals changes in the rate of expansion since the universe's birth 15 billion years ago. The more shallow the curve, the faster the rate of expansion. The curve changes noticeably about 7.5 billion years ago, when objects in the universe began flying apart as a faster rate. Astronomers theorize that the faster expansion rate is due to a mysterious, dark force that is pulling galaxies apart.

NASA/STSci/Ann Feild

More is unknown than is known. We know how much dark energy there is because we know how it affects the Universe's expansion. Other than that, it is a complete mystery. But it is an important mystery. It turns out that roughly 70% of the Universe is dark energy. Dark matter makes up about 25%. The rest - everything on Earth, everything ever observed with all of our instruments, all normal matter - adds up to less than 5% of the Universe. Come to think of it, maybe it shouldn't be called "normal" matter at all, since it is such a small fraction of the Universe.

One explanation for dark energy is that it is a property of space. Albert Einstein was the first person to realize that empty space is not nothing. Space has amazing properties, many of which are just beginning to be understood. The first property that Einstein discovered is that it is possible for more space to come into existence. Then one version of Einstein's gravity theory, the version that contains a cosmological constant, makes a second prediction: "empty space" can possess its own energy. Because this energy is a property of space itself, it would not be diluted as space expands. As more space comes into existence, more of this energy-of-space would appear. As a result, this form of energy would cause the Universe to expand faster and faster. Unfortunately, no one understands why the cosmological constant should even be there, much less why it would have exactly the right value to cause the observed acceleration of the Universe.

Dark Matter Core Defies Explanation

This image shows the distribution of dark matter, galaxies, and hot gas in the core of the merging galaxy cluster Abell 520. The result could present a challenge to basic theories of dark matter.

Another explanation for how space acquires energy comes from the quantum theory of matter. In this theory, "empty space" is actually full of temporary ("virtual") particles that continually form and then disappear. But when physicists tried to calculate how much energy this would give empty space, the answer came out wrong - wrong by a lot. The number came out 10¹²⁰ times too big. That's a 1 with 120 zeros after it. It's hard to get an answer that bad. So the mystery continues.

Another explanation for dark energy is that it is a new kind of dynamical energy fluid or field, something that fills all of space but something whose effect on the expansion of the Universe is the opposite of that of matter and normal energy. Some theorists have named this "quintessence," after the fifth element of the Greek philosophers. But, if quintessence is the answer, we still don't know what it is like, what it interacts with, or why it exists. So the mystery continues.

A last possibility is that Einstein's theory of gravity is not correct. That would not only affect the expansion of the Universe, but it would also affect the way that normal matter in galaxies and clusters of galaxies behaved. This fact would provide a way to decide if the solution to the dark energy problem is a new gravity theory or not: we could observe how galaxies come together in clusters. But if it does turn out that a new theory of gravity is needed, what kind of theory would it be? How could it correctly describe the motion of the bodies in the Solar System, as Einstein's theory is known to do, and still give us the different prediction for the Universe that we need? There are candidate theories, but none are compelling. So the mystery continues.

The thing that is needed to decide between dark energy possibilities - a property of space, a new dynamic fluid, or a new theory of gravity - is more data, better data.

What Is Dark Matter?

Abell 2744: Pandora's Cluster Revealed

One of the most complicated and dramatic collisions between galaxy clusters ever seen is captured in this new composite image of Abell 2744. The blue shows a map of the total mass concentration (mostly dark matter).

By fitting a theoretical model of the composition of the Universe to the combined set of cosmological observations, scientists have come up with the composition that we described above, ~70% dark energy, ~25% dark matter, ~5% normal matter. What is dark matter?

We are much more certain what dark matter is not than we are what it is. First, it is dark, meaning that it is not in the form of stars and planets that we see. Observations show that there is far too little visible matter in the Universe to make up the 25% required by the observations. Second, it is not in the form of dark clouds of normal matter, matter made up of particles called baryons. We know this because we would be able to detect baryonic clouds by their absorption of radiation passing through them. Third, dark matter is not antimatter, because we do not see the unique gamma rays that are produced when antimatter annihilates with matter. Finally, we can rule out large galaxy-sized black holes on the basis of how many gravitational lenses we see. High concentrations of matter bend light passing near them from objects further away, but we do not see enough lensing events to suggest that such objects to make up the required 25% dark matter contribution.

However, at this point, there are still a few dark matter possibilities that are viable. Baryonic matter could still make up the dark matter if it were all tied up in brown dwarfs or in small, dense chunks of heavy elements. These possibilities are known as massive compact halo objects, or "MACHOs". But the most common view is that dark matter is not baryonic at all, but that it is made up of other, more exotic particles like axions or WIMPS (Weakly Interacting Massive Particles).

These are all great articles on other closely related topics from our friend at NASA and othe space partners. Thanks GUYS!!!!!!

Recent Discoveries

March 2, 2012	Dark Matter Core Defies Explanation
January 10, 2012	El Gordo
January 10, 2012	Farthest Protocluster of Galaxies Ever Seen
October 13, 2011	New Dark Matter Census Survey
June 22, 2011	Abell 2744: Pandora's Cluster Revealed
May 19, 2011	GALEX Helps Confirm Nature of Dark Energy
April 12, 2011	Abell 383
March 14, 2011	Hubble Rules Out One Alternative to Dark Energy

Fighting for planetary research

Nasa science chief 'fighting' for planetary research

, BBC News website, The Woodlands, Texas

John Grunsfeld took over the science chief post in January

Related Stories

• Europe still keen on Mars missions
• Where now for Mars exploration?
• Nasa budget slashes Mars funding

Nasa's science chief has told planetary scientists he is "in there fighting for you" after the swingeing cuts proposed to the robotic exploration budget.

Former astronaut John Grunsfeld was speaking at the Lunar and Planetary Science Conference in Texas.

He faced more than 1,000 researchers at a special session to explain the 21% cut to planetary science in President Obama's latest budget request for Nasa.

The decision forced the agency to pull out of joint Mars missions with Europe.

Mr Grunsfeld took over as science chief on 4 January this year, after the key budgetary decisions had already been made. He has previously admitted he was disappointed when he learned of the proposals for planetary science.

"The Nasa budget was really the result of some tough choices and national priorities," he told his audience.

"The fact that the Nasa's planetary budget took such a great hit was one of those tough priority settings," and added: "It was a strategic decision."

Where the James Webb telescope has benefited, planetary science has lost out

The planetary exploration budget funds robotic missions to other bodies in the Solar System, such as Mars, the Moon and the outer planets.

The proposal for the Financial Year 2013 reduced the planetary science budget from $1.5bn to $1.2bn. The cuts would, in the words of one scientist, plunge the field into its biggest crisis since the 1980s and is considered likely to lead to the loss of up to 2,000 hi-tech jobs.

Although planetary science was a loser in general, Mars exploration was singled out for particular cuts, receiving $360.8m, which amounts to a reduction of almost 40% from the FY2012 estimate.

This kind of funding drop precludes Nasa from starting new missions in this part of its portfolio.

After the speech, Mr Grunsfeld fielded a question from Jim Bell, a planetary scientist and current president of the Planetary Society, a space advocacy organisation in California.

Prof Bell, who was one of the lead investigators on the Mars rovers mission, implored Mr Grunsfeld and Nasa's director of planetary science Jim Green to "fight back" against the plans, even if "you lose your jobs" because, he said, "it's the right thing to do".

In response, Mr Grunsfeld recalled a time in 2004 when he had considered resigning from Nasa's astronaut corps over a decision not to save the Hubble Space Telescope (HST).

He said: "History repeats itself… I decided on 4 January not to flee - I'm in there fighting for you."

'Weak' community?

Dr Mark Sykes, director of the Planetary Science Institute in Tucson, pressed Mr Grunsfeld on the James Webb Space Telescope (JWST).

The mission comes under a different budget at Nasa and represents the agency's successor to the HST. But it has already been delayed by several years and costs have ballooned by about $1.5bn.

Dr Sykes asked: "JWST went from $519m to $628m… it was about $100m that was contributed by the planetary science division to JWST. Is there a rationale for that level of contribution?"

The Mars Science Laboratory (Curiosity rover) could be the last surface mission for a while

Mr Grunsfeld replied that it was not a valuable exercise to try to "trace the dollars" and that if different divisions of science at Nasa were to fight, "we all lose".

After the session Dr Sykes told me: "Budgets are a conservative process and if you have a flat pot of money and something goes up and something comes down… it's a conservative process."

He added: "There is a little question about what's the motivation, or the policy underpinning that - who knows?"

But at a community forum at the LPSC on Tuesday, scientist and author Andy Chaikin said the cuts had occurred because "the planetary community is seen in some circles as being weak".

He added that the plans would be "starving the pipeline that sustains education and research in planetary science".

Spreading the pain

Mr Grunsfeld said that it would have been a mistake to spread cuts equally across Nasa's science portfolio: "The one way you can make sure that Nasa's dollars are less efficient is to take operating missions and those in development and say, 'you were going to launch in 2016, but now you can't go until '17 or '18.

"For the agency that means it's going to cost $200-$300m more. Planetary science happened to be in a place where we had just launched [Mars Science Laboratory], we had just launched [the Juno mission to Jupiter] and they could take the hit and not create a situation where there was a mission well through development that was going to get cut and it would have cost hundreds of millions more."

However, one researcher told me: "That's like saying things are coming to an end."

Many scientists are angry that the proposals ride roughshod over the results of the Planetary Decadal Survey, which laid out a vision for future exploration based on the priorities of the planetary science community.

This identified the goal of returning samples from Mars as a science priority. Joining Europe on its ExoMars programme, which aims to send landers to Mars in 2016 and 2018, would have led down that road.

However, some at Nasa had been reluctant to commit to so many costly "flagship" missions with a foreign agency, and have now got their wish.

The FY2013 budget proposal shifts funds to human spaceflight and space technology, in line with the agency's major commitments going forward to fund the development of a huge new rocket and capsule system to take astronauts beyond low-Earth orbit to destinations such as the Moon and asteroids.

But at the community forum session here at the LPSC, Dr Laurie Leshin from Nasa's Goddard Space Flight Center, said that it made no sense for Nasa to cut the scientists who were vital for supporting such missions, including allowing them to land safely at their destinations.

At the event, Prof Steve Squyres, who chaired the Planetary Decadal Survey, said the community had to put on a united front in order to fight the plans, not as scientists who studied Mars or outer planets, "but as space scientists".

The RED PLANET

Many people have many different ideas about our neighbor Mars. Some believe that the red planet has martians living there and have been for a long time underground due to the surface being bombarded by radiation. Others believe that there used to be a civilization long ago but due the natural geological processes stopping and because the red plane has a smaller surface area than earth and therefore losses heat much more quickly the planets natural processes stopped and then the sun has drenched the planet mars in deadly radiation for millions of years. Well many of these questions will be answered with the new rover mission. For about fifteen years we have had two ROVS on the surface of the red planet. This new rover is twice the size of the first two and has many new upgrades. for one the new rover will be able to analyze rock and detritus for and signs of water and life along with many other really neat abilities. For more on the new rovers abilities and other NASA new check out their web site......http://www.space.com

This artist's concept features NASA's Mars Science Laboratory Curiosity rover, a mobile robot for investigating Mars' past or present ability to sustain microbial life. Curiosity launched toward the Red Planet on Nov. 26, 2011. CREDIT: NASA/JPL-Caltech View full size image

NASA newest Mars rover, the Mars Science Laboratory Curiosity, launched toward the Red Planet on Nov. 26 at 10:02 a.m. EST (1502 GMT). The car-size spacecraft is the largest, most ambitious rover ever bound for Mars and is expected to seek out signs that Mars may once have been habitable for life.

Follow SPACE.com's complete coverage of the Mars Science Laboratory's launch and cruise to Mars in this story archive:

Latest NASA Update (Nov. 26):

"A signal from NASA's Mars Science Laboratory spacecraft, including the new Curiosity rover, has been received by officials on the ground. The spacecraft is flying free and headed for Mars after separation from the United Launch Alliance Atlas V rocket that started the spacecraft on its journey to the Red Planet. Liftoff was on time at 10:02 a.m. EST from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida."

Planet Mars

Visions of Mars

Robot explorers transform a distant object of wonder into intimate terrain.

Photograph by NASA/JPL/Cornell University

(Hear an interview with John Updike.)

Mars has long exerted a pull on the human imagination.The erratically moving red star in the sky was seen as sinister or violent by the ancients: The Greeks identified it with Ares, the god of war; the Babylonians named it after Nergal, god of the underworld. To the ancient Chinese, it was Ying-huo, the fire planet. Even after Copernicus proposed, in 1543, that the sun and not the Earth was the center of the local cosmos, the eccentricity of Mars's celestial motions continued as a puzzle until, in 1609, Johannes Kepler analyzed all the planetary orbits as ellipses, with the sun at one focus.

In that same year Galileo first observed Mars through a telescope. By the mid-17th century, telescopes had improved enough to make visible the seasonally growing and shrinking polar ice caps on Mars, and features such as Syrtis Major, a dark patch thought to be a shallow sea. The Italian astronomer Giovanni Cassini was able to observe certain features accurately enough to calculate the planet's rotation. The Martian day, he concluded, was forty minutes longer than our twenty-four hours; he was only three minutes off. While Venus, a closer and larger planetary neighbor, presented an impenetrable cloud cover, Mars showed a surface enough like Earth's to invite speculation about its habitation by life-forms.

Increasingly refined telescopes, challenged by the blurring effect of our own planet's thick and dynamic atmosphere, made possible ever more detailed maps of Mars, specifying seas and even marshes where seasonal variations in presumed vegetation came and went with the fluctuating ice caps. One of the keenest eyed cartographers of the planet was Giovanni Schiaparelli, who employed the Italian word canali for perceived linear connections between presumed bodies of water. The word could have been translated as "channels," but "canals" caught the imagination of the public and in particular that of Percival Lowell, a rich Boston Brahmin who in 1893 took up the cause of the canals as artifacts of a Martian civilization. As an astronomer, Lowell was an amateur and an enthusiast but not a crank. He built his own observatory on a mesa near Flagstaff, Arizona, more than 7,000 feet high and, in his own words, "far from the smoke of men"; his drawings of Mars were regarded as superior to Schiaparelli's even by astronomers hostile to the Bostonian's theories. Lowell proposed that Mars was a dying planet whose highly intelligent inhabitants were combating the increasing desiccation of their globe with a system of irrigation canals that distributed and conserved the dwindling water stored in the polar caps.

This vision, along with Lowell's stern Darwinism, was dramatized by H. G. Wells in one of science fiction's classics, The War of the Worlds (1898). The Earth-invading Martians, though hideous to behold and merciless in action, are allowed a dollop of dispassionate human sympathy. Employing advanced instruments and intelligences honed by "the immediate pressure of necessity," they enviously gaze across space at "our own warmer planet, green with vegetation and grey with water, with a cloudy atmosphere eloquent of fertility, with glimpses through its drifting cloud wisps of broad stretches of populous country and narrow, navy-crowded seas."

In the coming half century of Martian fancy, our neighboring planet served as a shadowy twin onto which earthly concerns, anxieties, and debates were projected. Such burning contemporary issues as colonialism, collectivism, and industrial depletion of natural resources found ample room for exposition in various Martian utopias. A minor vein of science fiction showed Mars as the site, more or less, of a Christian afterlife; C. S. Lewis's Out of the Silent Planet (1938) invented an unfallen world, Malacandra. Edgar Rice Burroughs's wildly popular series of Martian romances presented the dying planet as a rugged, racially diverse frontier where, in the words of its Earthling superhero John Carter, life is "a hard and pitiless struggle for existence." Following Burroughs, pulp science fiction, brushing aside possible anatomical differences, frequently mated Earthlings and Martians, the Martian usually the maiden in the match, and the male a virile Aryan aggressor from our own tough planet. The etiolated, brown-skinned, yellow-eyed Martians of Ray Bradbury's poetic and despairing The Martian Chronicles (1950) vanish under the coarse despoilment that human invasion has brought.

But all the fanciful Martian megafauna—Wells's leathery amalgams of tentacles and hugely evolved heads; American journalist Garrett Serviss's 15-foot-tall quasi red men; Burroughs's 10-foot, 4-armed, olive-skinned Tharks; Lewis's beaver-like hrossa and technically skilled pfifltriggi; and the "polar bear-sized creatures" that Carl Sagan imagined to be possibly roaming the brutally cold Martian surface—were swept into oblivion by the flyby photographs taken by Mariner 4 on July 14, 1965, from 6,000 miles away. The portion of Mars caught on an early digital camera showed no canals, no cities, no water, and no erosion or weathering. Mars more resembled the moon than the Earth. The pristine craters suggested that surface conditions had not changed in more than three billion years. The dying planet had been long dead.

Two more Mariner flybys, both launched in 1969, sent back 57 images that, in the words of the NASA release, "revealed Mars to be heavily cratered, bleak, cold, dry, nearly airless and generally hostile to any Earth-style life-forms." But Mariner 9, an orbiter launched in 1971, dispatched, over 146 days, 7,000 photographs of surprisingly varied and violent topography: volcanoes, of which the greatest, Olympus Mons, is 13 miles high, and a system of canyons, Valles Marineris, that on Earth would stretch from New York City to Los Angeles. Great arroyos and tear-shaped islands testified to massive floods in the Martian past, presumably of water, the sine qua non of life as Earth knows it. In 1976 the two Viking landers safely arrived on the Martian surface; the ingenious chemical experiments aboard yielded, on the question of life on Mars, ambiguous results whose conclusions are still being debated into the 21st century.

In the meantime, our geographical and geological intimacy with Mars grows. The triumphant deployment of the little Sojourner rover in 1997 was followed in 2004 by the even more spectacular success of two more durable rovers, Spirit and Opportunity. In four years of solar-powered travels on the red planet, the twin robots have relayed unprecedentedly detailed images, including many clearly of sedimentary rocks, suggesting the existence of ancient seas. The stark, russet-tinged photographs plant the viewer right on the surface; the ladderlike tracks of Spirit and Opportunity snake and gouge their way across rocks and dust that for eons have rested scarcely disturbed under salmon pink skies and a pearlescent sun. In this tranquil desolation, the irruption of our live curiosity and systematic purpose feels heroic.

Now the Phoenix mission, with its surpassingly intricate arm, scoop, imagers, and analyzers, takes us inches below the surface of dust, sand, and ice in Mars's north polar region. Spoonfuls of another planet's substance, their chemical ingredients volatilized, sorted, and identified, become indexes to cosmic history. Meanwhile, the Mars Reconnaissance Orbiter, the newest of three operational spacecraft circling the planet, feeds computers at the University of Arizona with astoundingly vivid and precise photographs of surface features. Some of these false-color images appear totally abstract, yet they yield to knowledgeable eyes riches of scientific information.

The dead planet is not so dead after all: Avalanches and dust storms are caught on camera, and at the poles a seasonal sublimation of dry ice produces erosion and movement. Dunes shift; dust devils trace dark scribbles on the delicate surface. Whether or not evidence of microbial or lichenous life emerges amid this far-off flux, Mars has become an ever nearer neighbor, a province of human knowledge. Dim and fanciful visions of the twinkling fire planet have led to panoramic close-ups beautiful beyond imagining.

John Updike's fiction and poetry have long revealed an interest in science. His latest novel is titled The Widows of Eastwick.

New tech in the robot world.

In new mass-production technique, robotic insects spring to life

February 15, 2012

Production method inspired by children's pop-up books enables rapid fabrication of tiny, complex devices

Cambridge, Mass. - February 15, 2012 - A new technique inspired by elegant pop-up books and origami will soon allow clones of robotic insects to be mass-produced by the sheet.

Devised by engineers at Harvard, the ingenious layering and folding process enables the rapid fabrication of not just microrobots, but a broad range of electromechanical devices.

In prototypes, 18 layers of carbon fiber, Kapton (a plastic film), titanium, brass, ceramic, and adhesive sheets have been laminated together in a complex, laser-cut design. The structure incorporates flexible hinges that allow the three-dimensional product—just 2.4 millimeters tall—to assemble in one movement, like a pop-up book.

The Harvard Monolithic Bee (or "Mobee") pops up within an assembly scaffold, which performs more than 20 origami assembly folds. Photos courtesy of Pratheev Sreetharan.

---

The entire product is approximately the size of a U.S. quarter, and dozens of these microrobots could be fabricated in parallel on a single sheet.

"This takes what is a craft, an artisanal process, and transforms it for automated mass production," says Pratheev Sreetharan (A.B. '06, S.M. '10), who co-developed the technique with J. Peter Whitney. Both are doctoral candidates at the Harvard School of Engineering and Applied Sciences (SEAS).

Sreetharan, Whitney, and their colleagues in the Harvard Microrobotics Laboratory at SEAS have been working for years to build bio-inspired, bee-sized robots that can fly and behave autonomously as a colony. Appropriate materials, hardware, control systems, and fabrication techniques did not exist prior to the RoboBees project, so each must be invented, developed, and integrated by a diverse team of researchers.

Less than a year ago, the group was using a painstaking and error-prone method to fold, align, and secure each of the minuscule parts and joints.

"You'd take a very fine tungsten wire and dip it in a little bit of superglue," explains Sreetharan. "Then, with that tiny ball of glue, you'd go in under a microscope like an arthroscopic surgeon and try to stick it in the right place."

"Until recently, the manual assembly process was the state of the art in this field," Sreetharan adds.

By the numbers

• Folding joints: 22
• Assembly scaffold folding joints: 115
• Total device folding joints: 137
• Number of brass pads for "glue" points: 52
• Total number of "glue" points: 24
• Mass: 90 mg
• By mass, one U.S. quarter = 63 Harvard Monolithic Bees
  

The same result can now be achieved—without human error—through locking mechanisms and dip soldering. The new process also enables the use of cured carbon fiber, which is rigid and easy to align, rather than uncured carbon fiber, which Sreetharan compares to "wet tissue paper."

"Our new techniques allow us to use any material including polymers, metals, ceramics, and composites," says principal investigator Rob Wood, an Associate Professor of Electrical Engineering at SEAS and a Core Faculty Member at the Wyss Institute for Biologically Inspired Engineering at Harvard.

"The ability to incorporate any type and number of material layers, along with integrated electronics, means that we can generate full systems in any three-dimensional shape," Wood says. "We've also demonstrated that we can create self-assembling devices by including pre-stressed materials."

The implications of this novel fabrication strategy go far beyond these micro-air vehicles. The same mass-production technique could be used for high-power switching, optical systems, and other tightly integrated electromechanical devices that have parts on the scale of micrometers to centimeters.

Moreover, the layering process builds on the manufacturing process currently used to make printed circuit boards, which means that the tools for creating large sheets of pop-up devices are common and abundant. It also means that the integration of electrical components is a natural extension of the fabrication process—particularly important for the size- and weight-constrained RoboBees project.

"In a larger device, you can take a robot leg, for example, open it up, and just bolt in circuit boards. We're so small that we don't get to do that. I can't put a structural mechanism in here and have it serve no electrical function."

Pointing to the carbon-fiber box truss that constitutes the pop-up bee's body frame, Sreetharan says, "Now, I can put chips all over that. I can build in sensors and control actuators."

A small portion of the CAD design for the Harvard Monolithic Bee illustrates the complexity of folds and joints necessary for its assembly. Using the old, manual process, every one of those parts would have to be cut, folded, assembled, and glued by hand. The bottom image illustrates the 18 layers of laser-cut materials that create the pop-up structure. Images courtesy of Pratheev Sreetharan.

---

Essentially, tiny robots can now be built by slightly bigger robots. Designing how all of the layers will fit together and fold, however, is still a very human task, requiring creativity and expertise. Standard computer-aided design (CAD) tools, typically intended for either flat, layered circuit boards or 3D objects, do not yet support devices that combine both.

Once the design is complete, though, fabrication can be fully automated, with accuracy and precision limited only by the machining tools and materials.

"The alignment is now better than we can currently measure," says Sreetharan. "I've verified it to better than 5 microns everywhere, and we've gone from a 15% yield to—well, I don't think I've ever had a failure."

The full fabrication process will be described in the March issue of the Journal of Micromechanics and Microengineering. Co-authors and collaborators, beside Whitney, Sreetharan, and Wood, include Kevin Ma, a graduate student at SEAS; and Marc Strauss, a research assistant in Wood's lab.

The Harvard Office of Technology Development is now developing a strategy to commercialize this technology. As part of this effort, they have filed patent applications on this work and are engaging with entrepreneurs, venture capitalists, and companies to identify disruptive applications in a range of industries.

The work was supported by the U.S. Army Research Laboratory, the National Science Foundation (through the Expeditions in Computing program), and the Wyss Institut

Entertainment

Built 1998

B 018 is a music club, a place of nocturnal survival. In the early months of 1998, the B 018 moved to the "Quarantaine", on a site that was better known for its macabre aura. The "Quarantaine" is located at the proximity of the port of Beirut. During the French protectorate, it was a place of quarantine for arriving crews. In the recent war it became the abode of Palestinian, Kurdish and South Lebanese refugees (20,000 in 1975). In January 1976, local militia men launched a radical attack that completely wiped out the area. The slums were demolished along with the kilometer long bordering wall that isolated the zone from the city. Over twenty years later, the scars of war are still perceptible through the disparity between the scarce urban fabric of the area and the densely populated neighborhoods located across the highway that borders the zone. The B 018 project is, first of all, a reaction to difficult and explosive conditions that are inherent to the history of its location and the contradictions that are implied by the implementation of an entertainment program on such a site. B 018 refuses to participate to the naïve amnesia that governs the post-war reconstruction efforts. The project is built below ground. Its façade is pressed into the ground to avoid the over exposure of a mass that could act as a rhetorical monument. The building is embedded in a circular concrete disc slightly above tarmac level. At rest, it is almost invisible. It comes to life in the late hours of the night when its articulated roof structure constructed in heavy metal retracts hydraulically. The opening of the roof exposes the club to the world above and reveals the cityscape as an urban backdrop to the patrons below. Its closing translates a voluntary disappearance, a gesture of recess. The building is encircled by concrete and tarmac rings. The automobiles' circular travel around the club and the concentric parking spots frame the building in a carousel formation. At night, the continuous motion of the visitors' cars animates the parking and becomes an integral element of the club's scenario. The entrance is located at the south end of the low-lying metal construction where a stair leads to two concessive "airlock" spaces manned by scowling bouncers. Strewn across the concrete pavement floor of the underground hall, the sofas with collapsible backs serve as elevated dancing surfaces that stage the performers.