Five Planets

Rethinking the Source of Earth’s Water

Earth, with its blue hue visible from space, is known for its abundant water – predominately locked in oceans – that may have come from an extraterrestrial source. New research indicates that the source of Earth’s water isn’t from ice-rich comets, but instead from water-bearing asteroids.

Discovery of fifth moon reignites Pluto planet debate

Pluto may not be a planet any more, but the discovery of its fifth moon means it can boast more satellites than the inner four planets combined. The finding could reignite the debate over the icy rock’s planetary status – or lack of. The find also suggests that the neighbourhood surrounding Pluto may be extremely dusty, which is bad news for those trying to a plot a safe course for spacecraft.

This is a collection of three posts from Centauri Dreams discussing the capturing of antimatter, and the use of it as a resource.

Antimatter is currently the most expensive physical substance that we know of – apparently, our going rate to ‘mine’ antimatter is $100 trillion per gram, which is just a touch more expensive than other substances. Which is rather a pity, because it’s quite useful as a fuel. The energy density of matter-antimatter fuel is orders of magnitude higher than anything else we currently can produce on Earth, even a fusion reaction. As an example, 10 milligrams of antimatter holds the same chemical energy as 120 tonnes of rocket fuel.

Apparently though, with the application of the right kind of solar powered harvesting machinery, we could produce a gram a day from Earth’s upper atmosphere. With it being stated that ten micrograms would get a spaceship to Jupiter, a gram a day would be more than enough for most uses.

As another option, there is the possibility of creating a linear accelerator based antimatter ‘factory’ down here on planet earth. Some of the latest research in the field suggests that the cost of this method could be as low as $10 million per milligram, which is an entirely acceptable rate in line with what we currently pay for nuclear energy generation of the same rate.

If we could ever produce antimatter at a decent rate, we would have an energy source that is 1,000 times more effective than a nuclear fission reaction, and one quite capable of opening up the entire solar system to use. Indeed, with an efficient engine design, local stars such as Proxima Centauri become appropriate targets for exploration, well within a human lifetime.

Unfortunately, all of this is far into the future, and likely will never occur during the lifetime of anyone I know.

Antimatter: Finding the Fuel

Antimatter: The Production Problem

Toward a Beamed Core Drive

An exceedingly long update detailing the life and times of Opportunity, who is now starting to wake up from the Martian winter. Spirit, unfortunately, is long gone at this point.

March came in like a lion and went out like a lamb at Meridiani Planum, Mars: Opportunity felt the cold wind on her solar panels, then “settled” in a little more, working through the depths of its fifth Martian winter, as the team honored one of its own up there, and the Mars Exploration Rover mission logged month number 99 of exploration.

Mars Exploration Rovers Update: Opportunity Gets Energy Boost and Works Through Depths of Winter

A lot has been written about the business prospects of Planetary Resources, Inc., the billionaire-backed space venture that recently announced its intention to mine platinum, and other metals, from near-earth asteroids. The firm claims that a single successful mining mission could bring it tens of trillions of dollars in revenue, and could potentially supply the raw materials for generations of computing devices. These are ambitious goals, but not everyone is convinced that Planetary Resources can muster the technology or the staying power to reach them. The firm’s critics have pointed out that flooding the market with asteroid-sized quantities of platinum, which currently sells for over $1,500 an ounce, could reduce its price considerably, endangering the business model of the entire enterprise. But even if Planetary Resources falls flat on its face, a serious (and seriously funded) attempt at asteroid mining could have interesting collateral effects—it could, for instance, entirely remake the way that we do science in space.  

Robots, Platinum, and Tiny Space Telescopes: The Pitch for Mining Asteroids

If you have an hour or so, this presentation to the British Interplanetary Society makes for interesting listening. It covers the full history of the use of wings on spacecraft, from the earliest launches to modern vehicles such as the XCOR Lynx and the Dreamchaser. And to top it all off, there’s an erudite English accent at work.

If a portion of Earth underwent a major cataclysm, how long would it take for life to recover? The 1980 eruption of Mount St. Helens is giving scientists a an unprecedented opportunity to witness a recovery from devastation, as the eruption leveled the surrounding forest, blasted away hundreds of meters of the mountain’s summit, and claimed 57 human lives. Landsat satellites have tracked the what has happened on the mountain, and how the forest was reclaimed — all on its own. This video shows a timelapse of the recovery, with annual images from 1979-2011 from the Landsat satellites, which acquired the images seen here between 1979 and 2011.

Want to build robot asteroid miners? Get in line

Well, it sure seems that way. Planetary Resources received over 2,000 applications for only a few jobs over the course of two weeks. Everyone wants to work on something that will change the way humans view life on Earth, and Planetary Resources is one of the very few companies that can guarentee it will.

Pulsar heavyweight champ challenges Einstein

It’s a star so dense it could cause the theory of general relativity to collapse. That’s quite a gravitational field.

The world that we live in is seeing a strange thing happen – visionaries are gathering large amounts of money to themselves, and are assuming risks that beforehand would not have been tolerated. Take Elon Musk, perhaps the poster child for all of this. He created Paypal, a company that revolutionized small-scale electronic payments. He then sold it to eBay, but rather than rest on his laurels or develop another software/service product, he decided to throw his entire fortune behind SpaceX and Tesla Motors. Tesla has floundered, but SpaceX may well pave the way for commercial use of space, and it has already become the first commercial entity to ever launch a reusable capsule to space and retrieve it.

And that environment has now spawned the most ambitious of them all – Planetary Resources. They’re going to harvest volatiles and metals from Near-Earth Objects (NEOs), asteroids that swing past the planet. And they’re backed by five or six billionaires, all of them technological visionaries. The business plan that they’re operating under is a multi-step process, first building small observation satellites to study asteroids, then beginning the initial mining phase not by going for high value metals, but for basic necessities such as water and oxygen.

This is a departure from the traditional descriptions of asteroid mining, almost all of which revolved around the extreme value of rare earth metals, gold, platinum, and similar elements. But water goes for $20,000 a litre in space, and if Planetary Resources can get their production costs under that figure, they’ll be able to sell to the ISS, and whatever commercial space stations exist at that time (Bigelow Aerospace, most likely). And demand for water and oxygen will never go away, instead increasing the more that humans use space.

Likewise, iron and nickel might be boring metals, but they’re extremely common in asteroids, and would make for a decent basic construction material for space stations and other structures. After all, one of the primary reasons for not using weighty metals in space construction to date is the cost. When launch costs are in the range of $20,000 a pound, using a lighter weight construction process is extremely important. But if the metal is already there, and relatively easily available (Nickel-Metal asteroids are often 95% nickel and iron), then much of the cost for construction can be reduced. Compared to the construction cost on Earth, it will still be astronomical, but then, that’s the nature of space.

All in all, the hope is that companies like Planetary Resources are able to sufficiently lower the costs of getting to space that corporations that generally thrive in lower margin environments can arrive. Of course, that will take a good long time and a great many risks, but one can hope that the process is now accelerated.

The images in the video above are taken from satellite data from 2005 to 2007, tracking the movement of all the Earth’s ocean currents. It’s spectacular.

According to the most popular theory, the Moon was created when a Mars-sized planet struck the Earth. The impactor was vaporised, and Earth’s mantle was blown off into Space. The pieces of mantle were large enough to coalesce in Earth orbit until they formed the Moon. The Giant Impactor theory became popular after Apollo Moon samples were found to resemble parts of Earth’s mantle.

The Moon first coalesced less 1/4 its present distance from Earth. Since that time 4.5 billion years ago the Moon has been slowly drifting away. This is interpreted as tidal forces transferring angular momentum from Earth’s rotation to the Moon. Apollo’s Lunar Laser Ranging Experiment measured this distance increasing at 3.82 cm/yr, anomalously high. If the Moon were today gaining angular momentum at that rate, it would have been in the same place as Earth only 1.5 billion years ago.

If the speed of light were slowly decreasing, time for light to return from the Moon would increase each year, making the Moon appear to recede faster as seen by LLRE. Change in the speed of light, predicted by the simple expression GM=tc^3, precisely accounts for the lunar anomaly. This is striking evidence that the speed of light is slowing today.

A recent study, appearing online in the Journal of Geophysical Research on February 29, 2012, has found clear evidence on Venus for a type of space weather outburst quite common at Earth, called a hot flow anomaly. These anomalies, also known as HFAs, cause a temporary reversal of the solar wind that normally moves past a planet. An HFA surge causes the material to flood backward, says David Sibeck, a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md., who studies HFAs at Earth and is a co-author on the paper.

“They are an amazing phenomenon,” says Sibeck. “Hot flow anomalies release so much energy that the solar wind is deflected, and can even move back toward the sun. That’s a lot of energy when you consider that the solar wind is supersonic — traveling faster than the speed of sound — and the HFA is strong enough to make it turn around.”

Space weather: Explosions on Venus

Creating some of life’s building blocks in space may be a bit like making a sandwich — you can make them cold or hot, according to new NASA research. This evidence that there is more than one way to make crucial components of life increases the likelihood that life emerged elsewhere in the Universe, according to the research team, and gives support to the theory that a “kit” of ready-made parts created in space and delivered to Earth by impacts from meteorites and comets assisted the origin of life.

Meteorites Reveal Another Way to Make Life

More than 50 years after the space age began, the final frontier is at last opening wide to private enterprise. And at the forefront of these new commercial operations is SpaceX, a company so ambitious that it is setting its sights as far as Mars.

Having successfully built and launched their own rocket designs into space, Space Exploration Technologies Corp, to give them their full name, have won NASA funding & contracts to develop and service future US transport to orbit.

A key test to come this year will be an unmanned flight by SpaceX’s own spacecraft capsule, called Dragon, on a test run to the International Space Station (ISS).

If all continues to go well, other Dragons will later roar into space as America’s regular shuttle replacement, carrying astronauts and supplies to the orbiting outpost.

SpaceX on the launchpad of a new era in space transport

Some things are impossible because they violate fundamental laws of the universe, as far as we know. The theory of relativity says that neither matter nor information can travel faster than light. Matter because an object reaches infinite mass at the speed of light. (Though the recent measurement of neutrinos apparently traveling faster than light remains to be explained, most physicists suspect it reflects a subtle error, not an overthrow of the theory of relativity.) Information because that would reverse the order of cause and effect for some observers, effectively enabling time travel and violating everything we think we know about how nature operates. Other things are impossible, or at least extremely difficult, because of practical or engineering limitations rather than fundamental ones.

Travel to the stars has both kinds of constraints. The fundamental one is that no spacecraft can reach, let alone exceed, the speed of light. But that speed of 300,000 km/second is so far beyond what our spacecraft now typically achieve – 16 km/second or less at launch – that it is not currently relevant to a discussion of interstellar travel, though it may be in the future.

A speed of a few km/second has allowed us to send people to the Moon, and probes to Mars, Saturn, and more, and so it might seem that we can reach the stars, too. But travel to the stars is qualitatively different. This was convincingly expressed at the first conference devoted to the possibility of reaching the stars, the 100 Year Starship (100YSS) event held in Orlando, Florida, which I attended last September.

Sponsored by DARPA (Defense Advanced Research Projects Agency) of the U.S. Department of Defense, 100YSS asked whether, within the next century, we can build a spacecraft capable of reaching the stars. DARPA does not necessarily see direct military use for interstellar travel, but it has often invested in unconventional ideas that yielded benefits for the military and for civil society. A starship project would have an excellent chance of producing valuable new science and technology.

Realizing the Impossible: Interstellar Travel

Apparently, they beat our ancestors to the crossing of the Med by 50,000 years. Not bad at all.

Neanderthals were ancient mariners

Life will find a way. Even if that way involves hiding under a bush on a James Bond villain’s hideout for 80 years.

Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years

Apparently, the theory of cosmic inflation is fairly sound, by our current understanding of physics.

According to calculations, the early universe required an accelerated cosmic expansion (inflation), a speed of sound faster than the speed of light, or extremely high cosmic energy to end up with our current universe. The third model actually demands such high energy that scientists would need to invoke a theory of quantum gravity like string theory to explain the extra dimensions of space-time that would pop up.

Our Early Universe: Inflation, or Something Totally Wacky?