Category Archives: Asteroids

NASA’s Next Destination is an Asteroid

For the last few decades, ever since the gradual decline of interest in the American space program, scientists and engineers have sought a way to get to Mars, a rather lofty goal that might be reachable within the next 20 years, but may perhaps be one of the longest planetary flights that astronauts have yet to undergo, with a great deal of equipment to be tested out first for safely landing on Mars’ thin atmosphere alone. While NASA still hopes to reach the red planet by 2035, their spaceflight program has a different short-term goal for next decade, one that might even be attractive to at least some of the types of people who were adamant against trips to the moon – putting an asteroid in lunar orbit.

You read it right. The plan unveiled yesterday by NASA officials has been called by some as the plan to give the moon its own moon – to capture an asteroid and safely place it within the orbit of our moon for closer study, allowing astronauts to land on it and sample it from the safety of a nearby orbit. Its the goal of the agency’s latest effort known as the Asteroid Redirect Mission (ARM), which hopes to bring about new technology that will be crucial in the mission to Mars and other deep space missions in the future.

NASA’s decision to kick off ARM was postponed for several months, while two individual teams investigated how to best pursue the mission objectives. In its original proposal, known as Option A, ARM proposed using a “grab and bag” approach, a robotic space tug is used to trap a small asteroid in its entirety, cover it in a protective sheath and then guide it towards the moon’s orbit. Option B costs about $100 million more, whitch will snatch the boulder directly, but was the winning option, as it provided more more operational flexibility, according to NASA’s associate administrator Robert Lightfoot.

In a recent conference call he took with reporters, Lightfoot noted that their decision was partially based in the fact that our telescopic surveys have not yet sighted any asteroids that are both small enough and slow-moving to fulfill Option A. Any asteroids suitable for harvesting would also be extremely difficult to categorize from Earth with the existing technology. Option A would therefore be “a one-shot deal,” had he chosen to carry it out, with many potential shortcomings should they choose the wrong target, whereas Option B would have a lot more to choose from.

“From what we know of the asteroids we’ve been to, they have boulders on the surface,” said Lightfoot. “I’m going to have multiple targets when I get there, is what it boils down to.” Implementing Option B would mean that ARM would then be allowed to capture and deliver a space boulder as large as 12 feet across and then carry it off to high lunar orbit.

This might sound to you like searching the entire beach for a grain of sand, considering the size of asteroid belts existing in our solar system, but NASA already has three potential candidates lined up for ARM: asteroids Itokawa, Bennu and 2008 EV5. The Japanese space agency’s craft Hayabusa paid a visit to Itokawa in 2005, and NASA’s OSIRIS-REx already plans to visit and extract new samples from asteroid Bennu, which it will reach by the year 2019. No spacecraft has yet orbited the 2008 EV5, and NASA has placed it on the top of their list for ARM targets. They hope to make their official target selection by 2019, according to Lightfoot.

“[2008 EV5] has been extensively observed” using infrared and radio telescopes,” said Lindley Johnson, the program executive at NASA’s Near-Earth Object Program. Scientists have been using the observations of Johnson’s team for determining the asteroid’s orbit, and also the size, shape, rate of spin and composition. 2008 EV5 has been described as ‘a slowly spinning 400-meter-wide walnut, with a prominent ridge wrapped around its middle.’ It is a carbonaceous asteroid, which means that it’s a composite of rock and also molecular organic compounds and water-rich minerals, containing much of the substance found in the primitive nebula, out of which the solar system condensed from. For astronauts who are privileged to walk on its surface, it may be the closest they’ll ever get to walking on an early primordial Earth. Bennu is also a carbonaceous asteroid, and very soon scientists may be able to hold a piece of the solar system from when it first originated once the OSIRIS-REx returns.

Science, however, is only ARM’s ulterior motive. Their goal, as stated, is to both test and create new potential technologies to improve spaceflight, particularly NASA’s Space Launch System heavy-lift rocket, the Orion deep-space crew capsule and also an advanced solar-electric propulsion engine that would be best suited for long-haul cargo trips such as the Mars mission. NASA has also sold the missions as being a potential step forward in showing how a spacecraft is capable of changing the orbits of asteroids that may pose threats to life on Earth, part of its “Redirect” program.

According to Lightfoot, NASA’s current plan hopes to launch the robotic tug into space by 2020, where it will spend two years navigating for its target. The robotic tug might spend up to 400 days near its target as it selects the right boulder. Once the tug makes its selection, it will then use the extra mass from its target to function as a “gravity tractor,” in which it will orbit the asteroid in a way that will slightly alter its trajectory. While this orbital shift may be slight, it will still be in the measurable range of ground-based instruments, and could prepare NASA for making stronger orbital shifts in the future, effectively averting an Armageddon-like scenario. Once the boulder is in its grasp, the robotic tug will then travel to high lunar orbit, where it shall anticipate the arrival of two astronauts via an Orion capsule, an encounter that could happen as soon as the end of 2025. The astronauts will then dock the robotic tug as they conduct spacewalks, investigating the boulder before it returns to Earth, meaning the astronauts will spend approximately an entire month in space preparing the target.

This all might sound exciting, but it’s actually a far cry from what was initially proposed with ARM, and both policy makers and engineers alike are treating it with mild enthusiasm, if not outright disdain. It’s also not without scientists who are critical of the mission. Among them is Mark Sykes, director of the Planetary Science Institute who is unsure of whether, despite the fairly low risks, this mission is of much practical value.

“It is not at all clear how this mission is necessary to advance the stated objective of sending humans to Mars,” Sykes says. “Or even its vicinity.”

There is also concern related to what the mission might mean for NASA’s public relations. The mission may stave off some recent criticism that the agency has not dedicated enough time to space travel. However, some scientists such as NASA’s Advisory Council chair Steve Squyres of Cornell University, feel that the mission may be little more than a tactic – fulfilling political expectations while putting off funding that could be better spent on going to Mars.

“If you’re going to spend $1.25 billion plus launch vehicle costs to do something,” said Squyres, during a council meeting back in January, “and you get the most important things by not going after the rock, don’t go after the rock.”

There are quite a few needs to be met before ARM is fully ready for its mission, such as a solar electric engine that may not be ready by the time of the launch.

The ARM mission was born back in 2010, shortly after President Obama canceled plans for a second manned lunar mission, deciding instead to have astronauts step on an asteroid by the year 2025. At the time, some experts suspected that this was a quicker way to bring humans to Mars, if they would first pick near targets such as the Martian moons Phobos and Deimos which are very reminiscent of asteroids. Unfortunately, NASA’s budget at the time did not have sufficient enough funds for building either the new heavy-lift rockets or deep-space crew capsules fast enough to fulfill that deadline. Sending a manned capsule to an asteroid within its native orbit would simply not be possible by the year 2025. However, there was a slight loophole in the president’s choice of words. Suppose NASA brought the asteroid to the astronauts using that funding? Thus, NASA’s research teams put together ARM.

James Sullivan
James Sullivan is the assistant editor of Brain World Magazine and a contributor to Truth Is Cool and OMNI Reboot. He can usually be found on TVTropes or RationalWiki when not exploiting life and science stories for another blog article.

NASA Researchers Recreate Building Blocks of Life at Ames Research Lab

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As much as we know about life on planet Earth, how it actually got here in the first place is still the subject of much investigation. Organic molecules probably first made it to Earth encased in meteorites – but the mystery lies in how conditions on an early Earth that made the developments of life in its most basic form possible.

Now researchers at NASA Ames studying abiogenesis – the chemical origin of life, have successfully managed to reproduce the compounds uracil, cytosine, and thymine, which make up three key components of our genetic material, in a laboratory. They found that a sample of ice containing pyrimidine, exposed to ultraviolet wavelengths – in a simulation of conditions in outer space are able to produce these basic building blocks of life.

It was originally believed that the first life originated in a warm pond – a primordial soup of sorts which the 1952 Urey-Miller experiment sought to recreate by passing an electrical discharge through a mixture of water, methane, ammonia, and hydrogen. Later, it was believed that mud was the medium that allowed life to begin, and experiments since Urey-Miller were successful in producing uracil and cytosine together – two key components of RNA, the polymer used to read DNA codes and synthesize proteins for life processes. RNA is the main ingredient of retroviruses, which replicate despite being non-living matter. Now, scientists have managed to replicate the basic structure for all three components of RNA with the ring-shaped molecule of Pyrimidine, a compound of carbon and nitrogen.

“We have demonstrated for the first time that we can make uracil, cytosine, and thymine, all three components of RNA and DNA, non-biologically in a laboratory under conditions found in space,” said researcher Michel Nuevo at NASA’s Ames Research Center in Moffett Field, California. “We are showing that these laboratory processes, which simulate conditions in outer space, can make several fundamental building blocks used by living organisms on Earth.”

In order to synthesize these compoinds, the researchers placed an ice sample onto a cold (approximately –440 degrees Fahrenheit) substrate in a chamber. The block of ice is then irradiated by high-energy ultraviolet (UV) photons exuded from a nearby hydrogen lamp. These photons break apart the ice’s chemical bonds, reducing the ice’s molecules to fragments which then recombine with each other and begin forming new compounds – among them are uracil, cytosine, and thymine.

For years, NASA Ames’ team of researchers have worked to recreate the environments within interstellar space and our own outer Solar System. Of particular interest in recent years was their discovery of a class of carbon-rich compounds, known as polycyclic aromatic hydrocarbons (PAHs), that are found in meteorites. These contain the most abundant carbon-rich compound seen throughout the universe. PAHs are usually structures containing several six-carbon rings bonded together in hexagon shapes, like honeycombs or a pattern of chicken wire.

The molecule pyrimidine has also been found in meteorites, but its exact origin remains unknown. Like the carbon heavy PAHs, pyrimidine may be created by the last bursts of energy given off by red giants when they die, or perhaps they bond together when caught in heavy clouds of interstellar dust and gasses.

“Molecules like pyrimidine have nitrogen atoms in their ring structures, which makes them somewhat wimpy. As a less stable molecule, it is more susceptible to destruction by radiation, compared to its counterparts that don’t have nitrogen,” said Scott Sandford, one of the space science researchers at Ames. “We wanted to test whether pyrimidine can survive in space, and whether it can undergo reactions that turn it into more complicated organic species, such as the nucleobases uracil, cytosine, and thymine.”

In their hypothesis, these researchers suspected that were the molecules of pyrimidine able to survive long enough, they would be able to migrate into the interstellar dust clouds. Once inside these dense clouds, they could then protect themselves against any of the harmful radiation from space. Hidden inside the clouds, they would mostly freeze into grains of dust.

They then tested this at the Ames Astrochemistry Laboratory. Their experiment revealed that freezing pyrimidine is in an ice primarily consisting of water, but also in cases where they ice contains traces of ammonia, methanol, or methane, the honeycomb molecules are much more protected against destruction by radiation than if they happened to be floating through space in a gaseous phase. Rather than being destroyed, these molecules began to take on new forms once frozen.

“We are trying to address the mechanisms in space that are forming these molecules. Considering what we produced in the laboratory, the chemistry of ice exposed to ultraviolet radiation may be an important linking step between what goes on in space and what fell to Earth early in its development,” said Christopher Materese, another researcher at NASA Ames who had been studying the properties of PAH’s.

“Nobody really understands how life got started on Earth. Our experiments suggest that once the Earth formed, many of the building blocks of life were likely present from the beginning. Since we are simulating universal astrophysical conditions, the same is likely wherever planets are formed,” says Sandford.

Perhaps a great deal of the research may further reveal that life in some form is an inevitable chemical occurrence.

Cloudy With a Chance of Iron Rain? How Prehistoric Earth May Have Gotten Its Metal

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It’s a well known fact that our solar system, and particularly our planet, has endured a number of disasters from its very beginning as a chunk of rock some 4.6 billion years ago. An early collision with Mars, aptly named for the god of war, may be among the events responsible for first bringing life to Earth. Another collision is responsible for the chunk of earth that broke off to form our moon. Relentless meteors have pummeled its surface ever since, some quite harmless, while others brought about massive extinction events. Earth in its very beginning was hardly a hospitable place to be.

Among the many objects to hit the Earth within its first billion years, many of the meteors were rich in iron. These collisions could have led to it becoming so prevalent across the planet as well as one of the essential minerals needed to support many different forms of life. Iron in these early days would have infiltrated the atmosphere onto Earth’s crust, but also would have melted its mantle at high rates as well. These same meteorites may have also left behind metals such as gold or platinum which easily bond with iron. What the model has not convincingly explained yet, is how the iron is so prevalent that it makes up so much of the mantle of our planet.

Researcher Richard Kraus of the Lawrence Livermore National Laboratory of California, wanted to take the research a step further, in order to find the best way that would measure exactly how iron would behave under such harsh conditions as our planet’s first days, and what would sort of extreme heat would be necessary for iron to vaporize completely.

“We’re never really going to be able to get a situation where we can simulate the actual planetary impact, with objects a thousand kilometres across. It would just be too destructive,” says Kraus. “We’re taking a step back and saying, let’s make a fundamental measure of the entropy of iron.”

In order to investigate further, the team employed the Z machine from the Sandia National Laboratory of Albuquerque, New Mexico, a machine used to accelerate metals to the most extreme speeds with the help of high magnetic fields.

For their project, they shot small iron samples with aluminium plates, each less than a centimeter square and about 1.2 millimeters thick. These plates were accelerated between 30,000 to 40,000 miles per hour. The result was a powerful collision in which shock waves rattled through the iron, causing the pieces to compress and then heat up before they eventually vaporized. The researchers were then able to determine how the properties they found in this lab-made iron rain worked by having them drop upon a window composed of quartz, solid enough to withstand the dropping particles.

Through their experimentation, they soon discovered that it required considerably less pressure for them to vaporize the iron than researchers had once thought – in fact, a full 40 per cent below their original estimation. This realization is painting an entirely new vision of what the early Earth must have looked like. The meteors entering our orbit would typically vaporize upon their impact due to the extreme temperatures and pressure as they accelerated at speeds perhaps faster than those tested under lab conditions. These vanquished meteors would then send a boiling hot plume composed primarily of iron and rock dust into the air. This mixture would afterwards rain down, allowing it to easily and thoroughly blend into the Earth’s mantle.

The way in which iron behaves under pressure also suffices to explain why our moon has significantly less metal across its surface compared to Earth. Many suspect that since it broke off from the Earth, the two bodies should have a similar if not identical composition. Any iron that vaporized from meteor collisions on the moon would instead be able to escape back in space, considering that the moon has relatively low levels of gravity.

The beginning of our planet, may have been little more than chemistry – reactions of not only celestial bodies that smashed into each other, but of what they left behind.

“The reason we’re able to mine gold and make jewellery out of it, and mine palladium and make catalytic converters, is because the silicates have much higher abundances of these elements than one might expect,” said Richard Walker from the University of Maryland. “This is a pretty good way of explaining how they got here and why they’re not located 2900 kilometres below your feet in the core.”

Kraus’ work was published this week in the journal Nature Geoscience.

Could Dark Matter Be Behind Earth’s Extinction Events?

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Earth’s orbit along the Galactic Disc, is a long yet predictable journey that lasts for eons, but not without consequence, as Michael Rampino, a professor of biology at New York University recently observed. Rampino’s newest research, published in the Monthly Notices of the Royal Astronomical Society, believes that these infrequent rotations have coincided with the state of life on Earth.

While we often think of the comet that brought a rather dramatic end to the dinosaurs 65 million years ago when we hear of extinction, it was hardly the first time that many species died out together. Nor was it even remotely the worst. That distinction belongs to the Permian-Triassic extinction event, which occurred 252 million years ago, coinciding with the Galactic Disc rotation, in which 83 percent of all life became extinct – owing to not only volcanic events but ocean acidification and the impact of several meteors. It took approximately 10 million years for much of the life left on Earth to replenish itself. While it took more than one event to make things hostile for life on Earth, Rampino has attributed the increased number of meteoric impacts to a buildup of dark matter, which may upset the orbits of comets and also increase heating at the Earth’s core – igniting volcanic activity, a trend currently being seen in Iceland.

Even the era that paleontologists purport to be the golden age of Dinosaurs – the Jurassic period – in which some of the largest species of sauropods thrived, was preceded by another violent extinction event – the Triassic-Jurassic extinction – taking place 201.3 million years ago. It took about 10,000 years, partially because of increased activity at a massive underwater volcano known as the Central Atlantic Magmatic Province, as well as several meteoric events which took place in Europe. Today, these periods are known by the rock layers they left behind, yet it is clear that each are caused by the same violent reactions in nature and the resulting change in climate.

The Galactic Disc is a region of the Milky Way Galaxy that defines its shape and contains our solar system, amidst a heavy clutter of stars and clouds of cosmic dust and reactive gasses. Yet, surrounding the cluster, is the elusive dark matter, particles which are primarily known because of the remarkable gravity they release, impervious to light and other forms of electromagnetic radiation.

According to prior studies, the Earth makes a rotation around the Galactic Disc once every 250 million years. However, the path is not always circular but wavy, as the Sun and other planets weave their way in and out of the crowded disc at intervals of approximately 30 million years or so. The Cretaceous-Paleocene event also coincides with these patterns.

So why does dark matter in particular seem like the culprit in these occurrences? When comets move through the disc, concentrations of dark matter can sometimes intensify to the point that they begin to throw comets off course, sometimes this instability causes them to collide with the planet, acts that have defined the shape of Earth throughout its history, and also perhaps supplying it with the very amino acids necessary to sustain life. But dark matter has another somewhat more pernicious impact on our planet in a different way, too.

As the Earth is exposed to dark matter on its rotations, Rampino learned that dark matter could essentially build up within the planetary core, producing an intense heat as its particles collide with each other inside. Eventually the heat builds up considerable pressure, leading to mountain building, volcanic eruptions, and even reversals in the planet’s magnetic field. The history of rises and falls in sea levels also shows a peak happening every 30 million years.

The new model of dark matter and its interactions with planets as they move across the Galaxy could significantly impact how we perceive geological and biological development. Already, our current understanding of the Earth’s natural history is one of violent and destructive events. Dark matter could be a critical cause behind it all. Already, in what geologists have petitioned to refer to as the Anthropocene Era (the Age of Humans – due to our species’ shaping of the planet for better or for worse), many other researchers believe we are in the midst of a sixth extinction event – with climbing levels of CO2 adding to the acidification of the ocean each year. Like dark matter, humans have the power to impact the universe too.

To put this all in perspective, Rampino said in his paper: “We are fortunate enough to live on a planet that is ideal for the development of complex life. But the history of Earth is punctuated by large scale extinction events, some of which we struggle to explain. It may be that dark matter — the nature of which is still unclear but which makes up around a quarter of the universe — holds the answer. As well as being important on the largest scales, dark matter may have a direct influence on life on Earth.”

Wales Skies To Light Up By Huge “Ship-Sized” Asteroid

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Wales Skies To Light Up By Huge “Ship-Sized” Asteroid

In a once 200-year event, the skies of Wales will be lit up by a “cruise ship sized” asteroid, which is set to pass 1.2km (745,000 miles) from Earth. It’s a real close shave for the planet.

According to Jonathan Powell, an Abergavenny astronomer, the 2004 BL86 asteroid would be a rare sight indeed.

Powell, who is the secretary at the Abergavenny and District Astronomical Society, said the asteroid can be seen by looking to the southeast between the bright star Sirius and the planet Jupiter, around 20:00 GMT.

He said the anticipated asteroid sighting caused many folks to sit up and take notice, with many local astronomers expected to get together in the Wales countryside to get the best look of it… away from any street lights.

Powell said an asteroid passes the planet every year; but, because of its size and timing, the 2004 BL86 asteroid is the reason for all the excitement, allowing people to get a good look at it in Wales’ nighttime sky.

He said the majority of asteroids that pass Earth are extremely small, which means they can’t even be seen with amateur telescopes.

If people in Wales want to see this “cruise-ship sized” asteroid, all they need are powerful telescopes or binoculars and look up at into the sky around 8 p.m. and later to see it pass. Powell said it’s that big and that close.

He said the asteroid, which is going to travel very slowly unlike other things in the sky, is going to be three times the distance from the earth and moon.

According to NASA, the large asteroid is going to be closest known space rock to the planet until 2027 when the 1999 AN10 whizzes by Earth.