Posted on by Nancy Atkinson

How to Deflect an Asteroid with Today’s Technology

Artist concept of a space tug. Credit: NASA

Apollo 9 astronaut Rusty Schweickart is among an international group of people championing the need for the human race to prepare for what will certainly happen one day: an asteroid threat to Earth. In an article on Universe Today published yesterday, Schweickart said the technology is available today to send a mission to an asteroid in an attempt to move it, or change its orbit so that an asteroid that threatens to hit Earth will pass by harmlessly. What would such a mission entail?

In a phone interview, Schweickart described two types of “deflection campaigns” for a threatening asteroid: a kinetic impact would roughly “push” the asteroid into a different orbit, and a gravity tractor would “tug slowly” on the asteroid to precisely “trim” the resultant change course by using nothing more than the gravitational attraction between the two bodies. Together these two methods comprise a deflection campaign.

Artist Impression of Deep Impact - Credit: NASA

“In a way, the kinetic impact was demonstrated by the Deep Impact mission back in 2005,” said Schweickart. “But that was a very big target and a small impactor that had relatively no effect on the comet. So, we haven’t really demonstrated the capability to have the guidance necessary to deflect a moderately sized asteroid.”

Most important, the gravity tractor spacecraft would arrive prior to the kinetic impactor, precisely determine the asteroid’s orbit and observe the kinetic impact to determine its effectiveness. Following the kinetic impact it would then determine whether or not any adjustment trim were required.

“You want to know what happens when you do a kinetic impact, so you want an ‘observer’ spacecraft up there as well,” Schweickart explained. “You don’t do a kinetic impact without an observation, because the impactor destroys itself in the process and without the observer you wouldn’t know what happened except by tracking the object over time, which is not the best way to find out whether you got the job done.”

So, 10-15 years ahead of an impact threat — or 50 years if you have that much time — an observer spacecraft is sent up. “This, in fact, would also be a gravity tractor,” Schweickart said. “It doesn’t have to be real big, but bigger gets the job done a little faster. The feature you are interested in the outset is not the gravity tractor but the transponder that flies in formation with the asteroid and you track the NEO, and back on Earth we can know exactly where it is.”

Schweickart said even from ground tracking, we couldn’t get as precise an orbit determination of an NEO as we could by sending a spacecraft to the object. Additionally, generally speaking, we may not know when we send an observer spacecraft what action will be required; whether an impact will be required or if we could rely on the gravity tractor. “You may launch at the latest possible time, but at that time the probability of impact may be 1 in 5 or 1 or 2,” Schweickart said. “So the first thing you are going to do with the observer spacecraft is make a precise orbit determination and now you’re going to know if it really will impact Earth and even perhaps where it will impact.”

Artist concept of an impactor heading towards an asteroid. Credit: ESA

After the precise orbit is known, the required action would be determined. “So now, if needed you launch a kinetic impactor and now you know what job has to be done,” Schweickart said. “As the impactor is getting ready to impact the asteroid, the observer spacecraft pulls back and images what is going on so you can confirm the impact was solid, –not a glancing blow — and then after impact is done, the observer spacecraft goes back in and makes another precision orbit determination so that you can confirm that you changed its velocity so that it no longer will hit the Earth.”

The second issue is, even if the NEO’s orbit has been changed so that it won’t hit Earth this time around, there’s the possibility that during its near miss it might go through what is called a “keyhole,” whereby Earth’s gravity would affect it just enough that it would make an impact during a subsequent encounter with Earth. This is a concern with the asteroid Apophis, which is projected to miss Earth in 2029, but depending on several factors, could pass through a keyhole causing it to return to hit Earth in 2036.

“So if it does go through that keyhole,” said Schweickart, “now you can use the gravity tractor capability of the spacecraft to make a small adjustment so that it goes between keyholes on that close approach. And now you have a complete verified deflection campaign.”

Schweickart said a Delta-sized rocket would be able to get a spacecraft to meet up with an asteroid. “A Delta rocket would work,” he said, “but if there is a more challenging orbit we might have to use something bigger, or we may have to use a gravity assist and do mission planning for type of thing which hasn’t been done yet. So we can get there, we can do it – but ultimately we will probably need a heavy lift vehicle.”
As for the spacecraft, we can use a design similar to vehicles that have already been sent into space.

“A gravity tractor could be like Deep Space 1 that launched in 1998,” Schweickart said. “ You can make any spacecraft into a gravity tractor fairly easily.”

Rusty Schweickart

But it hasn’t been demonstrated and Schweickart says we need to do so.

“We need to demonstrate it because we – NASA, the technical community, the international community — need to learn what you find out when you do something for the first time,” he said. “Playing a concerto in front of an audience is quite different from playing it alone in your house.”

Posted on by Nancy Atkinson

More Recent Landslides Spotted on Mars

Recent Landslide in Zunil Crater on Mars. Credit: NASA/JPL/University of Arizona

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Thanks to the Mars Reconnaisance Orbiter and the on-board HiRISE camera, scientists are able to monitor Mars for changes taking place on the landscape. They do this by comparing older images with newer ones, and also by seeing “fresh” features — like this recent landslide in Zunil Crater. “The color and albedo patterns indicate that a landslide occurred here very recently–too recently to have been re-covered by dust,” writes Alfred McEwen, principal investigator of HiRISE, writing on the camera’s website. “Looking for changes such as this will help us to better understand active processes.” McEwen said the landslide could have been triggered by a Marsquake or a small impact event.”

See more recent landslides below:

This landslide was spotted by Stu Atkinson; boulders and debris are below a steep north polar boundary scarp. Credit: NASA/JPL/University of Arizona

Our ‘eagle-eyed’ pal Stuart Atkinson found this landslide on a steep scarp in the north polar region. It looks as though a lot of rock has fallen from the cliff, and discussion among other image artists on UnmannedSpaceflight.com indicated that the blue areas could easily be patches of ice deposited from the cliff face. You can see the original image at the HiRISE website.

Frosted Gullies in the Northern Summer. Credit: NASA/JPL/University of Arizona

This image is so amazing, in that from orbit, we are looking down the side of a crater wall, where gullies have formed. There are two schools of thought on these types of gullies: one, many scientists believe that these gullies have been carved by liquid water, and were carved recently, so this recent, present-day activity is of immense interest.

A second opinion is that accumulations of frost in the gully alcoves starts an avalanche of loose material that does not involve liquid water. The MRO scientists will continue to analyze many images like this in order to try and answer the broader question of whether liquid water is responsible for the the gullies, landslides and avalanches or not.

andslides along the Walls of Bahram Vallis. Credit: NASA/JPL/University of Arizona

This image of Bahram Vallis has large mounds of material at the base of the valley floor. These deposits of material have the characteristic shape of rotational landslides or slumps on Earth where material along the entire wall slumps down and piles debris at the base of the slope, “much like a person who slumps down the back of a chair,” writes Frank Chuang from the HiRISE team. “Right at the cliff edge at the top of the slope, the shape of the area where the valley wall gave way to a landslide is not straight, but rather curved or semi-circular. This is typical of large landslides where the failure area has an arcuate “crown” shape. The fact that landslides have occurred here indicates that the valley walls are not stable and the materials respond to Martian gravity with mass movements.”

See more images at the HiRISE website.

Posted on by Nancy Atkinson

X-37B Update: Space Plane Spotted Again in Orbit

X37-B spaceplane captured in orbit in May 2010 by UT reader Brent 'Bozo.'

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Here’s an update on the US Air Force’s secret X-37B space plane, which went missing last week — at least for us Earth-bound satellite watchers (surely the Air Force knows exactly where it is!). Spaceweather.com reports that the plane has been spotted again by a skywatcher from South Africa, Greg Roberts on October 12. Spaceweather says, “An analysis of the sighting by satellite expert Ted Molczan suggests that the X-37B has maneuvered into an orbit 54 km lower than before.” This is at least the second time the space plane’s orbit has changed, but at least we now know it is still in orbit and hasn’t landed.

If you want to try and see the X-37B yourself, visit the Heaven’s Above website, and Spaceweather also has a way to track the plane, too.

Posted on by Nancy Atkinson

Even ‘Weakling’ Magnetars are Strong and Powerful

An artistic impression of a magnetar with a very complicated magnetic field at its interior and a simple small dipolar field outside. Credits: ESA - Author: Christophe Carreau

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The name alone, “magnetar” elicits a magnificent, powerful and strong astronomical object, and most of these “magnetic stars” are whirling, X-ray blasting dynamos, shooting out strong bursts of energy. But there are some magnetars which seem to have a softer, quieter side, and are called soft gamma repeaters and anomalous X-ray pulsars. However, they might not be as soft as they appear. A team of astronomers using the several different space- and Earth-based observatories have found a supposed ‘weakling’ was only masking its superpowers. The new findings indicate the presence of a huge internal magnetic field in these seemingly less powerful pulsars, which is not matched by their surface magnetic field.

Magnetars are a type of neutron stars, which are the collapsed remains of massive, rapidly rotating stars. They collapses down to tiny cores, with the hot neutron liquid rising and falling from the center to the crust setting up a dynamo effect, creating that incredible magnetic field. Although they are on average only about 30km in diameter, a magnetar can have a magnetic field billions of times that of our Sun.

It was thought that dramatic flares and bursts of energy came from only the strong class of magnetars, but these same features have been observed emanating from a weakly magnetized, slowly rotating pulsar.

“We have now discovered bursts and flares, i.e. magnetar-like activity, from a new pulsar whose magnetic field is very low,” said Dr Silvia Zane, from UCL’s (University College London) Mullard Space Science Laboratory, and an author of the research.

The neutron star, SGR 0418+5729, was discovered on June 5, 2009 when the Fermi Gamma-ray Space Telescope detected bursts of gamma-rays from this object. Follow-up observations four days later with the Rossi X-Ray Timing Explorer (RXTE) showed that, in addition to sporadic X-ray bursts, the neutron star exhibits persistent X-ray emission with regular pulsations that indicate that the star has a rotational period of 9.1 seconds.

What makes SGR 0418 different from similar neutron stars is that, unlike those stars that are observed to be gradually rotating more slowly, continued monitoring of SGR 0418 over a span of 490 days has revealed no evidence that its rotation is decreasing.

“It is the very first time this has been observed and the discovery poses the question of where the powering mechanism is in this case. At this point, we are also interested in how many of the other normal, low field neutron stars that populate the galaxy can at some point wake up and manifest themselves as a flaring source,” said Zane.

The team of astronomers, led by Dr. Nanda Rea of Institut de Ciencies de l’Espai (ICE-CSIC, IEEC) in Barcelona, wonder how large an imbalance can be maintained between the surface and interior magnetic fields. SGR 0418 represents an important test case.

“If further observations by Chandra and other satellites push the surface magnetic field limit lower, then theorists may have to dig deeper for an explanation of this enigmatic object,” said Rea.

Sources: Chandra Blog, University College, London (via Eurekalert)

Posted on by Nancy Atkinson

The Milky Way Might Be Square

The Pinwheel Galaxy has areas of straight arms. The Milky Way might, as well. Image Credit: NASA

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Just like being stuck inside and not being able to see what the outside of your house looks like, we’re trapped inside the Milky Way galaxy and aren’t able to see its complete structure. Most of us have this vision of a circular, spiral galaxy with gracefully curving spiral arms. Nope, says a group of astronomers from Brazil. The Milky Way might be square. Not like a box, but, in places, the spiral arms are straight rather than curved, giving the Milky Way a distinctly square look. And our solar system sits right on one the straightest parts of an outer arm.

It really IS hip to be square.

The map of the Milky Way has been redrawn several times since the first attempts in the 1950’s using radio telescopes to trace out the spiral arms of our home galaxy. However, the concept of our galaxy having square-ish arms is not so farfetched: we know of the Pinwheel Galaxy, above, that has areas of straight and squared off arms, and a 2008 study using the Very Long Baseline Array found that instead of arms neatly circling the galactic center, the stars mapped traced a more elliptical orbit. But most of the maps of the Milky Way have assumed that the material in our galaxy orbits the center in a circular fashion, so having arms stars that don’t follow this path come as somewhat of a surprise.

Jaques Lepine and his team from the University of Sao Paulo in Brazil wanted to obtain the equivalent of a ”face-on” map of the spiral arms of our Galaxy, so they studied the spectra produced by clouds of carbon monosulphide, a common gas in our galaxy, rather than the usual suspect of ionized hydrogen.

They were able to determine velocity information for 870 regions of the Milky Way which is a larger number than that of previous studies based on classical HII regions, so they’ve created a new map of the galaxy with detail never seen before. “One way to improve the description of the spiral arms is to increase the number of objects used to trace them,” the team writes in their paper.

The distribution of CS sources and maser sources in the galactic plane with the Cepheid stars in orange and the young open clusters in green. The Sun is represented by a yellow dot. Credit: Lepine, et al.

Not only did they find evidence for straight places in the arms, but they also found an additional third arm. A 2008 study by the Spitzer Space Telescope had demoted the number of arms from four to two, but other studies, including an earlier one by Levine have said three. So, yes, there is some uncertainty on the number of arms. The new arm is about 30,000 light years from the galactic core at a longitude of between 80 and 140 degrees. This one is rounded however, “with strong inward curvature.”

“Basically, our results confirm the main aspects of the spiral structure revealed by the studies of HII regions,” said Lepine and his team. “For instance if we move horizontally across the figure, to the right or to the left of the Galactic center, we find roughly 3 spiral arms on each side, like the previous works. There are departures from the pure logarithmic spirals, with segments of arms that are almost straight lines.”

Drawing a map of the Milky Way is a challenging task, since we only have an edge-on view of the galaxy in which we reside. To top it off, it’s full of dust and gas that muck up the view in the visible light spectrum. So, we have to rely on other spectra.

We may not ever know exactly what our galaxy would look like when viewed from other worlds, but we’ll keep trying.

Read the team’s paper: The spiral structure of the Galaxy revealed by CS sources and evidence for the 4:1 resonance, Lepine, et al.

Additional source: Technology Review Blog

Posted on by Jon Voisey

Missing Molecules in Exoplanet Atmospheres

Artist's View of Extrasolar Planet HD 189733b

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Every day, I wake up and flip through the titles and abstracts of recent articles posted to arXiv. With increasing regularity, papers pop up announcing the discovery of a new extra-solar planet. At this point, I keep scrolling. How many more hot Jupiters do you really want to hear about? If it’s a record setter in some way, I’ll read it. Another way I’ll pay attention is if there’s reports of detections of spectroscopic detection of components of the atmosphere. While a fistful of transiting planets have had spectral lines discovered, they’re still pretty rare and new discoveries will help constrain our understanding of how planets form.

The holy grail in this field would be to discover elemental signatures of molecules that don’t form naturally and are characteristic of life (as we know it). In 2008, a paper announced the first detection of CO2 in an exoplanet atmosphere (that of HD 189733b), which, although not exclusively, is one of the tracer molecules for life. While HD 189733b isn’t a candidate for searches for ET, it was still a notable first.

Then again, perhaps not. A new study casts doubt on the discovery as well as the report of various molecules in the atmospheres of another exoplanet.

Thus far there have been two methods by which astronomers have attempted to identify molecular species in the atmosphere of exoplanets. The first is by using starlight, filtered by the planet’s atmosphere to search for spectral lines that are only present during transit. The difficulty with this method is that, spreading the light out to detect the spectra weakens the signal, sometimes down to the very point that it’s lost in systematic noise from the telescope itself. The alternative is to use photometric observations, which look at the change in light in different color ranges, to characterize the molecules. Since the ranges are all lumped together, this can improve the signal, but this is a relatively new technique and statistical methodology for this technique is still shaky. Additionally, since only one filter can be used at a time, the observations must generally be taken on different transits, which allow the characteristics of the star to change due to star spots.

The 2008 study by Swain et al. that announced the presence of CO2 used the first of these methods. Their trouble started the following year when a followup study by Sing et al. failed to reproduce the results. In their paper, Sing’s team stated,”Either the planet’s transmission spectrum is variable, or residual systematic errors still plague the edges of the Swain et al. spectrum.”

The new study, by Gibson, Pont, and Aigrain (working from the Universities of Oxford and Exeter) suggests that the claims of Swain’s team were a result of the latter. They suggest that the signal is swamped with more noise than Swain et al. accounted for. This noise comes from the telescope itself (in this case Hubble since these observations would need to be made out of Earth’s atmosphere which would add its own spectral signature). Specifically, they report that since there’s changes in the state of the detector itself that are often hard to identify and correct for, Swain’s team underestimated the error, leading to a false positive. Gibson’s team was able to reproduce the results using Swain’s method, but when they applied a more complete method which didn’t assume that the detector could be calibrated so easily by using observations of the star outside the transit and on different Hubble orbits, the estimation of the errors increased significantly, swamping the signal Swain claimed to have observed.

Gibson’s team also reviewed the case of detections of molecules in the atmosphere of an extra solar planet around XO-1 (on which Tinetti et al. reported to have found methane, water, and CO2). In both cases, they again find that detections of were overstated and the ability to tease signal from the data was dependent on questionable methods.

This week seems to be a bad week for those hoping to find life on extra-solar planets. With this article casting doubt on our ability to detect molecules in distant atmospheres and the recent caution on the detection of Gliese 581g, one might worry about our ability to explore these new frontiers, but what this really underscores is the need to refine our techniques and keep taking deeper looks. This has been a frank reassessment of the current state of knowledge, but does not in any way claim to limit our future discoveries. Additionally, this is how science works; scientists review each others data and conclusions. So, looking on the bright side, science works, even if it’s not exactly telling us what we’d like to hear.

Posted on by Nancy Atkinson

Viewing Alert: Virgin Galactic Flight Featured on Nat Geo Channel

Mojave, CA: Test pilot Brian Binnie in pressure suit. Looking into the windows are pressure suit vendor Jack Bassick, Space Program Manager for Scaled Composites Matt Stinemetze and crew member Terry Agold. (Photo Credit: © Virgin Galactic/ Mark Greenberg)

Here’s some exclusive video of the first glide flight of SpaceShipTwo earlier this week, shared by the National Geographic Channel, which has a new documentary series about Virgin Galactic premiering Monday, October 18, at 10 p.m. ET/PT. (Check your local listings at the Nat Geo Channel website). The series will cover maverick entrepreneur Sir Richard Branson and legendary aeronautical engineer Burt Rutan as they strive to be first to make space tourism an everyday reality. Also included in the premiere episode will be the backstory of the venture, including Rutan’s win of the Ansari X Prize with SpaceShipOne and WhiteKnightOne.

National Geographic Channel also shared a few images from Sunday’s flight, below.

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The underside of WhiteKnightTwo during flight. (Photo Credit: © Virgin Galactic/ Mark Greenberg)
Mojave, CA: SpaceShipTwo in the hangar with its nose exposed. (Photo Credit: © Antenna Films/ Tyrone Billingsley)
Posted on by Matt Williams

How Does Carbon Capture Work?

High concentrations of carbon dioxide (in red) tend to congregate in the northern hemisphere during colder months, when plants can't absorb as much from the atmosphere. This picture is based on a NASA Goddard computer model from ground-based observations and depicts concentrations on March 30, 2006. Credit: NASA's Goddard Space Flight Center/B. Putman/YouTube (screenshot)

What if it were possible to just suck all the harmful pollutants out of the air so that they wouldn’t be such a nuisance? What if it were also possible to convert these atmospheric pollutants back into fossil fuels, or possibly ecologically-friendly bio fuels? Why, then we would be able to worry far less about smog, respiratory illnesses, and the effects that high concentrations of these gases have on the planet.

This is the basis of Carbon Capture, a relatively new concept where carbon dioxide is captured at point sources – such as factories, natural-gas plants, fuel plants, major cities, or any other place where large concentrations of CO² are known to be found. This CO² can then be stored for future use, converted into biofuels, or simply put back into the Earth so that it doesn’t enter the atmosphere.

Description:

Like many other recent developments, carbon capture is part of a new set of procedures that are collectively known as geoengineering. The purpose of these procedures are to alter the climate to counteract the effects of global warming, generally by targeting one of the chief greenhouse gases. The technology has existed for some time, but it has only been in recent years that it has been proposed as a means of combating climate change as well.

Schematic showing both terrestrial and geological sequestration of carbon dioxide emissions from a coal-fired plant. Credit: web.ornl.gov
Schematic showing both terrestrial and geological sequestration of carbon dioxide emissions from a coal-fired plant. Credit: web.ornl.gov

Currently, carbon capture is most often employed in plants that rely on fossil fuel burning to generate electricity. This process is performed in one of three basic ways – post-combustion, pre-combustion and oxy-fuel combustion. Post-combustion involves removing CO2 after the fossil fuel is burned and is converted into a flue gas, which consists of CO2, water vapor, sulfur dioxides and nitrogen oxide.

When the gases travel through a smokestack or chimney, CO² is captured by a “filter” which actually consists of solvents that are used to absorb CO2 and water vapor. This technique is effective in that such filters can be retrofitted to older plants, avoiding the need for a costly power plant overhaul.

Benefits and Challenges:

The results of these processes have so far been encouraging – which boast the possibility of up to 90 % of CO² being removed from emissions (depending on the type of plant and the method used). However, there are concerns that some of these processes add to the overall cost and energy consumption of power plants.

According to 2005 report by the Intergovernmental Panel on Climate Change (IPCC), the additional costs range from 24 to 40% for coal power plants, 11 to 22% for natural gas plants, and 14 to 25% for coal-based gasification combined cycle systems. The additional power consumption also creates more in the way of emissions.

Vehicle emissions are one of the main sources of carbon dioxide today. Credit: ucsusa.org

In addition, while CC operations are capable of drastically reducing CO², they can add other pollutants to the air. The amounts of kind of pollutants depend on the technology, and range from ammonia and nitrogen oxides (NO and NO²) to sulfur oxides and disulfur oxides (SO, SO², SO³, S²O, S²O³. etc.). However, researchers are developing new techniques which they hope will reduce both costs and consumption and not generate additional pollutants.

Examples:

A good example of the Carbon Capture process is the Petro Nova project, a coal-fired power plant in Texas. This plant began being upgraded by the US Dept. of Energy (DOE) in 2014 to accommodate the largest post-combustion carbon-capture operation in the world.

Consisting of filters that would capture the emissions, and infrastructure that would place it back in the Earth, the DOE estimates that this operation will be capable of capturing 1.4 million tons of CO2 that previously would have been released into the air.

In the case of pre-combustion, CO² is trapped before the fossil fuel is even burned. Here, coal, oil or natural gas is heated in pure oxygen, resulting in a mix of carbon monoxide and hydrogen. This mix is then treated in a catalytic converter with steam, which then produces more hydrogen and carbon dioxide.

The US Department of Energy's (DoE) Petro Nova project, which will be the argest post-combustion carbon capture operation in the world. Credit: DOE
When complete, the US Department of Energy’s (DoE) Petro Nova will be the largest post-combustion carbon capture operation in the world. Credit: DOE

These gases are then fed into flasks where they are treated with amine (which binds with the CO² but not hydrogen); the mixture is then heated, causing the CO² to rise where it can be collected. In the final process (oxy-fuel combustion), fossil fuel is burned in oxygen, resulting in a gas mixture of steam and CO². The steam and carbon dioxide are separated by cooling and compressing the gas stream, and once separated, the CO² is removed.

Other efforts at carbon capture include building urban structures with special facilities to extract CO² from the air. Examples of this include the Torre de Especialidades in Mexico City – a hospital that is surrounded by a 2500 m² facade composed of Prosolve370e. Designed by Berlin-based firm Elegant Embellishments, this specially-shaped facade is able to channel air through its lattices and relies on chemical processes to filter out smog.

China’s Phoenix Towers – a planned-project for a series of towers in Wuhan, China (which will also be the world’s tallest) – is also expected to be equipped with a carbon capture operation. As part of the designers vision of creating a building that is both impressively tall and sustainable, these include special coatings on the outside of the structures that will draw CO² out of the local city air.

Then there’s the idea for “artificial trees“, which was put forward by Professor Klaus Lackner of the Department of Earth and Environmental Engineering at Columbia University. Consisting of plastic fronds that are coated with a resin that contains sodium carbonation – which when combined with carbon dioxide creates sodium bicarbonate (aka. baking soda) – these “trees” consume CO² in much the same way real trees do.

A cost-effective version of the same technology used to scrub CO² from air in submarines and space shuttles, the fronds are then cleaned using water which, when combined with the sodium bicarbonate, yields a solution that can easily be converted into biofuel.

In all cases, the process of Carbon Capture comes down to finding ways to remove harmful pollutants from the air to reduce humanity’s footprint. Storage and reuse also enter into the equation in the hopes of giving researchers more time to develop alternative energy sources.

We have written many interesting articles about carbon capture here at Universe Today. Here’s What is Carbon Dioxide?, What Causes Air Pollution?, What if we Burn Everything?, Global Warming Watch: How Carbon Dioxide Bleeds Across The Earth, and World Needs to Aim for Near-Zero Carbon Emissions.

For more information on how Carbon Capture works, be sure to check out this video from the Carbon Capture and Storage Organization:

If you’d like more info on Earth, check out NASA’s Solar System Exploration Guide on Earth. And here’s a link to NASA’s Earth Observatory.

We’ve also have Astronomy Cast episodes all about planet Earth and Climate Change. Listen here, Episode 51: Earth, Episode 308: Climate Change.

Sources:

Posted on by Nancy Atkinson

Is the World Ready for An Asteroid Threat? Apollo’s Schweickart Pushes for Action

Computer generated simulation of an asteroid strike on the Earth. Credit: Don Davis/AFP/Getty Images

If we discover an asteroid heading directly towards Earth, are we ready to deal with the challenges of either deflection strategies or an evacuation prior to impact? Apollo 9 astronaut Rusty Schweickart has spent years championing the need for the human race to prepare for what will certainly happen one day: an asteroid threat to Earth. Schweickart is Chairman of the Board of the B612 Foundation, a non-profit private foundation that supports the development and testing of a spaceflight concept to protect the Earth from future asteroid impacts, and he says we have the technology today to deal with it, but nothing has been verified or tested. “We need to mobilize that technology and achieve an international consensus on what actions should be taken,” he told Universe Today.

Schweickart also co-chairs — with another former astronaut, Tom Jones — the Planetary Defense Task Force of the NASA Advisory Council. On October 6, 2010, the Task Force submitted a list of five recommendations to the Council to suggest how NASA should organize, investigate, prepare, and lead national and international efforts defending our planet from an asteroid impact.

Rusty Schweickart

“Our report and recommendations are a necessary, but not sufficient element of a sequence of actions which hopefully will lead to humanity being able to prevent future asteroid impacts with Earth,” Schweickart explained. “Assuming positive action by OSTP (Office of Science and Technology Policy) and the Congress, we’ll be well on our way to preventing future impact disasters.”

The report stresses that NASA should significantly improve the ability to discover and track potential NEO impactors to allow for early detection, develop effective impact mitigation techniques, and prepare an adequate response to the range of potential impact scenarios.

These recommendations have been approved by the Advisory Council, and the report was submitted to the NASA Administrator. Then, the Office of Science and Technology Policy (OSTP) is supposed to make a decision by tomorrow – Friday, October 15, 2010 –to make assignments in the US government as to what the breakdown of work should be to protect the Earth from an asteroid impact.

Among the recommendations in the PDTF report is developing mitigation techniques. But could NASA do this type of work within their new budget? “People intuitively think that if you’re going to be pushing asteroids around, that work will take over NASA,” said Schweickart said in a phone interview with Universe Today . “Wrong. It would be a ripple in NASA’s budget, a pimple, 1.5-2.0 percent at the most of NASA’s annual budget for 10 years then dropping back to less than 0.5%. It does not displace anything else that NASA is doing. It would be a small budgetary issue, but the importance of it is huge. This saves lives, protects the global environment, and saves future generations.”

*Update (10/16/10) Schweickart asked to add to his comments about budgetary needs, as there were some misinterpretations. “I certainly did not intend that it be interpreted as no budget increment is needed! In fact our report makes very clear that we strongly recommend that Congress increment the existing budget for this purpose and not take it out of existing programs. It is not costly, but other NASA programs should not be penalized in order to support a responsible, public safety program which would amount to only a 1.5-2.0% increment in the NASA budget.”

Artist concept of a space tug. Credit: NASA

The technology needed exists today, Schweickart said, “that is, we do not have to go into a big technology development program in order to deflect most asteroids that would pose a threat of impact. However, that technology has not been put together in a system design, and not been verified, tested or demonstrated that it could actually deflect an asteroid. So, we need to test everything – test the very sequence we would use for a deflection campaign.”

The best way to test it would be to have NASA, or perhaps a consortium of space agencies, carry out an actual mission to test the entire system.

“Not with an asteroid that threatens an impact,” said Schweickart, “but with an asteroid that is just minding its own business, and we’d have the opportunity to show we can change its orbit slightly in a controlled way.”

The crew of Apollo 9: Commander James McDivitt, Command Module Pilot Dave Scott and Lunar Module Pilot Rusty Schweickart. Credit: NASA

Schweickart said the B612 foundation, and the Association of Space Explorers (ASE; the professional organization of astronauts and cosmonauts from around the world) and every planetary defense conference held recently has discussed the need for such a capability validation.

But the recommendations made by the PDTF are, for now just suggestions, and certainly not a mandate for NASA to prepare in a meaningful way for an asteroid threat.

“There’s no official design of a deflection mission because there is no responsibility to do it,” Schweickart said. “Right now, NASA’s assignment is only to find these asteroids. Period. That’s it.”

But, with the October 15 deadline almost here, Schweickart is hopeful. “Hopefully, that will begin the process of NASA actually having this responsibility,” he said, “and that Congress will respect that and a budget be allocated in order to do the job. Then mission planners can start designing demonstration missions.”

However, if the past is any indication, any mandate wouldn’t necessarily mean a mission would happen soon.

The Pan-STARRS telescope on Haleakala, Hawaii. Photograph by Rob Ratkowski for the PS1SC

Congress directed NASA to do the “Spaceguard” survey to find all asteroids around 40 meters and larger by 2020. “To come close to achieving that, we need to have new telescopes that will have greater capabilities than what we’ve been using to date,” said Schweickart. “Right now the Pan-STARRS telescope has the equivalent of one eye squinting, and it is not exactly knocking everybody’s socks off. LSST (Large Synoptic Survey Telescope) is still hundreds of millions of dollars before being a fully funded project.”

Schweickart said the Task Force heard presentations on perhaps better ways to complete that Congressional goal and their report indicates that at least 87% of the large asteroids whose impacts could pose a global threat to our civilization have been discovered. Right now, none pose a credible threat of a collision with Earth for the foreseeable future. But the discovery rate of the much more numerous smaller NEOs, — which represent a regional or local impact hazard — “will soon confront us with objects presenting worrisome but uncertain probabilities for a future collision with Earth. Such situations will appear more frequently as the discovery rate increases, and the nation presently has no clear policy on how to address such a situation,” the report says.

“Congress’s favorite thing to do is to tell you to do something and not give you any money for it,” Schweickart said. “That is not very responsible and it doesn’t always work and it’s not the right way a government should operate, especially where public safety is at issue. Therefore it is important that the OSTP lead the way on this issue on October 15.”

Tomorrow: What would an asteroid deflection campaign entail?

For more information:
B612 Foundation

Planetary Defense Task Force of the NASA Advisory Council

Office of Science and Technology Policy

Pan-STARRS

Large Synoptic Survey Telescope