Doomsday Paranoia Prompts the Search for Threats outside of Earth

December 22, 2012, was a good day for some; this is because the world is still standing and did not come to an end the day before as some doomsday prophecies have theorized. However, while Dec 21 may have passed without incident, this does not mean mankind is out of the woods yet. Letting our guards down may be a little bit premature as astronomers have detected an asteroid heading right for Earth.

The asteroid is estimated to be about 140 meters and was discovered by scientists from the University of Hawaii. While the asteroid will just barely miss our planet by about 890,000 kilometers, the fact that a behemoth rock is able to come that close is reasonable cause for alarm.

The reason we should worry is because that very same asteroid could change course and be headed back at Earth’s direction in the year 2040. This is due to a phenomenon known as the Yarkovsky effect. The effect occurs when an asteroid absorbs energy from the sun, which can alter the original direction of the object’s trajectory.

The asteroid in question is relatively the same mass as the one that slammed into an uninhabited area of Siberia in 1908, which caused an impact comparable to that of 1,000 atomic bombs going off at once.

Most astronomers agree that being hit by an asteroid is not a matter of “if” but “when.” For this reason, The B612 Foundation, a California based organization, is in the process of obtaining a half billion dollar fund for an infrared space telescope that is capable of detecting large celestial rocks that may pose a threat to Earth.

The telescope they hope to produce is called the Sentinel and will orbit the planet and take pictures of the sky and relay it back home. Detection is the key because we cannot stop what we don’t see. It is estimated that the Sentinel will be able to capture the locations of about 10,000 new asteroids every month.

Life on Mars?

A new study by NASA finds that if life has ever existed on Mars, it had to have been underground.

Ever since clay minerals were initially discovered on Mars in 2005, scientists have thought warm and wet conditions which could have possibly supported life may have existed. This is because clay is formed when stone and water interact with one another.

However, researchers analyzing orbiter data from over 350 areas of the planet’s surface have found that the type of clay which is formed underground is abundant on Mars, while the type of clay which is formed above the surface is quite rare. Conditions on the red planet are not especially conducive to water above the planet’s surface.

From Universe Today:

But there’s a problem with Mars’ atmosphere – it is not thick enough now for water to be retained on Mars’ surface, and there is no scientific consensus that it was ever thick enough in the past to have allowed water to remain on the surface.
According to NASA, the study, which is published in the current issue of the journal Nature, backs up a hypothesis that warm water was present only on the planet’s surface for geologically short periods of time.

But don’t worry — this doesn’t rule out the possibility of life on the red planet.

NASA Hunts For New Asteroids

NASA said on Thursday it identified upwards of 90 percent of giant near-Earth asteroids, including ones that are as big as the one which was said to have killed the last generation of dinosaurs eons ago. Amy Mainzer of the NASA Jet Propulsion Laboratory said:

“We know now where most of them are and where most of them are going. That really has reduced our risk…Fewer does not mean none…There are still tens of thousands out there that are left to find.”

The fresh census comes from data from NASA’s sky-mapping spacecraft called Wide-field Infrared Survey Explorer, or WISE, that launched in 2009 to seek out near-Earth objects, stars, galaxies and other cosmic targets.

Unlike sky surveys that have come before, WISE has extremely sensitive instruments which can pick out both light and dark objects, allowing it to receive the most accurate count yet of near-Earth asteroids. The spacecraft only takes a small sample of asteroids of different sizes before estimating how great the population would end up being.

For the very largest asteroids – greater than 3,300 feet across – NASA says 911 of the 981 that are said to exist have been found.

Former estimates put the number of medium-sized asteroids at 35,000, however WISE data indicate there are some 19,500 between 330 and 3,300 feet wide. Only about 5,200 were found and scientists said that there still is tons of work left to identify the potentially hazardous ones.

Alas, WISE isn’t yet totally equipped to detect the more than a million smallest asteroids which could cause damage should they impact planet Earth.

By locating the majority of the giant asteroids, NASA has gone ahead and fulfilled a goal that was set by Congress in 1998. More recently however, the space agency was asked to find 90 percent of asteroids which are at least 460 feet in diameter – just a little smaller than the Superdome in New Orleans – come the year 2020.

Meteor Shower Packed Earth With Gold

According to a new study published in the Nature Journal by researchers at the University of Bristol, roughly 3.9 billion years ago a gigantic meteor shower of glittering gold and platinum fell on earth. The ancient meteor shower serves as an explanation for why tens of thousands of times more gold exists today on earth’s crust and mantle than was initially thought to have existed.

Prior to this study, however, so many scientists pointed to the meteorite theory, however no substantial evidence was actually there to support the theory; that is, until now.

According to The National Geographic, contemporary scientists have put this hypothesis to the test by analyzing the oldest rocks in the world; those discovered in Greenland in 2008, and afterward comparing them to the makeup of other rocks found elsewhere around the globe.

Matthias Willbold of the University of Bristol study said:

“We hoped that by analyzing these rocks we could get an idea of how the Earth looked before that meteoritic bombardment, so we can estimate how much meteoritic material was added to the Earth…Our work shows that most of the precious metals on which our economies and many key industrial processes are based have been added to our planet by lucky coincidence when the Earth was hit by about 20 billion billion tonnes of asteroidal material…”

So the next time that you put on that charming gold piece of jewelry, just remember to thank your lucky stars. Based on the differing isotopes that were found from those two samples of rocks, researchers finally concluded that an ancient meteor shower had to have occurred.

The study in the journal, Nature:

Many precious, ‘iron-loving’ metals, such as gold, are surprisingly abundant in the accessible parts of the Earth, given the efficiency with which core formation should have removed them to the planet’s deep interior. One explanation of their over-abundance is a ‘late veneer’—a flux of meteorites added to the Earth after core formation as a ‘terminal’ bombardment that culminated in the cratering of the Moon. Some 3.8 billion-year-old rocks from Isua, Greenland, are derived from sources that retain an isotopic memory of events pre-dating this cataclysmic meteorite shower. These Isua samples thus provide a window on the composition of the Earth before such a late veneer and allow a direct test of its importance in modifying the composition of the planet. Using high-precision (less than 6 parts per million, 2 standard deviations) tungsten isotope analyses of these rocks, here we show that they have a isotopic tungsten ratio 182W/184W that is significantly higher (about 13 parts per million) than modern terrestrial samples. This finding is in good agreement with the expected influence of a late veneer. We also show that alternative interpretations, such as partial remixing of a deep-mantle reservoir formed in the Hadean eon (more than four billion years ago) or core–mantle interaction, do not explain the W isotope data well. The decrease in mantle 182W/184W occurs during the Archean eon (about four to three billion years ago), potentially on the same timescale as a notable decrease in 142Nd/144Nd (refs 3 and 6). We speculate that both observations can be explained if late meteorite bombardment triggered the onset of the current style of mantle convection.

Telescope Array Refunded

An assortment of 42 radio telescopes seeking signs of intelligent life in the universe has received enough funding by private donors to keep the effort going.

The array was a joint project between the SETI Institute and the UC Berkeley Astronomy Laboratory, but earlier this year was shut down due to the loss of National Science Foundation grants and state budget cuts.

Senior SETI Institute astronomer Seth Shostak said, “But people still think this very fundamental question – is there somebody out there as intelligent or more so than us? – is important and worth doing…”
The telescopes will be turned on again come September, they are recalibrated and will operate 24 hours a day for the rest of the year as more funds are sought.

The array costs $2.5 million a year to operate with a staff of 10 people. The SETI Institute has an $18 million budget and 140 employees. The funding comes from donors, NASA and the National Science Foundation.

SETI Institute CEO Tom Pierson told supporters it is his objective to raise $5 million so that the radio dishes may be pointed at 1,235 new so-called “exoplanets” which were announced in February by NASA’s Kepler mission.

The telescopes are not only used to search for E.T.s, but also to contribute to the research of black holes, pulsars and magnetic fields in the Milky Way.

Last June the SETI website read:

At the SETI Institute, we’ve made a name for ourselves exploring space. But it’s our community here on Earth — passionate, science-minded and creative — that truly defines us. That’s why we’re launching SETIstars, an initiative to connect us more closely than ever with the constellation of visionaries and supporters that make our work possible.

Priority one is getting the Allen Telescope Array (ATA) back online as soon as possible and once again fixing our gaze on the stars.

The ATA is a powerful field of linked radio telescopes that enable countless avenues of astronomical study, chief among them the search for evidence of extraterrestrial civilizations and insight into the nature of our cosmic origins. In the wake of a recent funding shortfall, however, this invaluable tool lies dormant and our vision of the universe around us has gone dark. With your help, we can change that.

Asteroid Time!

According to NASA a newly discovered asteroid will experience a close encounter with Earth this coming Monday; but worry not – it will not spell disaster.

NASA’s Near-Earth Object Program Office contends that the small space rock – called 2011 MD – will pass 7,500 miles over Earth’s surface over the southern Atlantic Ocean.

While it will come close, it is not a distance record holder. Earlier in the year, a tiny asteroid flew by even closer; that is within 3,400 miles of the Blue Planet.

The last asteroid measures 33 feet long and was discovered with New Mexican telescopes. Scientists say that asteroids this size can sail past Earth every six years.

The asteroid will briefly be seen rather brightly; well, that is bright enough such that medium-size telescopes may be able to spot it.

Moon Eclipse To Last Longer Than Usual

This year’s first total eclipse of the moon will last an unusually long time.

That is, unless you live in Canada or the United States. North America will not be privy to Wednesday’s lunar spectacle.

The period when earth’s shadow completely blocks the moon will last 1 hour and 40 minutes. The last time the moon was covered for so long was back in July 2000, when it lasted 7 minutes longer.

Normally, the full moon glows with reflected sunlight. A total lunar eclipse happens when the moon glides through the long shadow cast by the Earth and is blocked from the sunlight illuminating it.

As the moon plunges deeper into the shadow of the earth, the disk appears to gradually change color, turning from silver to red or orange. This is because some indirect sunlight still reaches the moon after passing through the atmosphere, which scatters blue light blue. Only red light hits the moon.

Because the moon will pass close to the center of the earth’s shadow, the total eclipse phase will last longer than usual.

The entire eclipse should last a little over 5 1/2 hours. Observers in Europe will miss the first part of the show because it will happen before the moon rises. Eastern Asia and eastern Australia will not catch the final stages, which will happen after the moon sets. Portions of South America will be able see the moon completely shrouded.

Spirit AWOL

The chances of ever again hearing from the stuck Mars rover, Spirit, is becoming more and more slim now that it has officially failed to respond to calls from Earth, repeatedly.

SpiritHowever, NASA will make one last-ditch attempt to communicate with Spirit. If there continues to be no contact in the next month, the space agency will scale back its listening campaign for Spirit and focus on its healthy companion, Opportunity.

The solar-powered rover got stuck in a sand trap in 2009 during a routine drive. Despite efforts to break free, it remained stuck and could not tilt toward the sun as the Martian winter was ’round the corner. It ultimately went into hibernation, lacking an adequate amount of energy to reach its solar panels.

Engineers had expected Spirit to wake up once there was maximum sunlight where it’s trapped. But that point came and went earlier this month with no response.

Ray Arvidson, of Washington University in St. Louis said:

“I would be surprised if we re-establish communication — happy but surprised…It’s been so long.”

Ground controllers are attempting to page Spirit over a range of frequencies and at various times during the day in the event its internal clock stopped working and it loses track of time. They also are commanding the rover to turn on its backup radio transmitter in case the central one is dead.

At some point, NASA will have to declare Spirit lost if there’s no word. When that happens, efforts will be reduced to sporadic listening for it through the end of the year, Callas said.

Both Opportunity and Spirit parachuted to polar sides of planet Mars in 2004. They worked together, beyond their original, three-month mission during which they discovered geologic evidence of water on the red planet.

While Spirit’s odometer stayed stuck at 4.8 miles, Opportunity ceased to explore the rim of Santa Maria crater on Mars and is currently rolling toward another crater. So far it has racked up 16.6 miles.

Jim Bell, an astronomer from Arizona State University said the loss of communication came at the worst possible time because Spirit was doing valuable science while it was immobile.

Bell said:

“It’s disappointing if we have, in fact, lost the mission…But it’s the best kind of disappointment you can have. We had a phenomenal adventure with that rover.”

Theories about Planets in Orbit

The total number of confirmed planets orbiting stars now more than 500. However, many of the newly discovered star systems defy existing models of how planets form.

As popular theory holds, planets are made from disks of gas and dust left over after star birth.
It has long been held that the large, gassy planets like Saturn and Jupiter first took shape in the far reaches before migrating inward, as gravitational drag from leftover gas and dust eroded their orbits. The migration process ceased when most of the gas and dust had been swept up to make various objects, leaving the planets exactly where we find them today.

According to this theory, other stars with planets should have gotten similar starts.
It is totally possible though some planets are born with eccentric orbits, moving around their stars in elongated ovals. But as a migrating planet spirals closer toward its star, gravitational drag should smooth out its orbit, like an object circling a drain.

The eight planets in our solar system all have circular orbits, and models of planet-forming disks suggest most other star systems are about the same.

In truth, however, about one in three of the known exoplanets has a circular or near-circular orbit.

The eight planets of our solar system orbit in the same direction around what is known as the ecliptic. That is a flat plane almost aligned with the equator. This makes complete sense if planets take shape inside the flat disks of material rotating around newborn stars.

Models are based on the belief that gravitational drag in these disks is the top influence on planets as they migrate. Based on such a theory, planets should stay in the ecliptic and continue to follow stars’ rotations.

However, one in three exoplanets’ orbits are “misaligned.” For instance, some orbit in the opposite directions as their stars’ rotations, and others are tilted out of the ecliptic, like weather satellites crossing over Earth’s Poles rather than the Equator.

Thunderstorms and Antimatter

Thunderstorms are able to shoot beams of antimatter into space; beams that are so intense they may be seen by spacecraft thousands of miles away.

Matter is made of subatomic particles such as protons and electrons. Whereas, antimatter is made of particles that have the same spins and masses as their counterparts though with opposite charges and magnetic properties.

Radiation detectors, recently, on NASA’s Fermi Gamma-ray Space Telescope lighted up for roughly 30 milliseconds with the characteristic signature of positrons, the antimatter counterparts of electrons.

Scientists were able to trace this burst of concentrated radiation back to a lightning flash over Namibia in North Africa, some 3,000 miles away from the Earth-orbiting telescope, which was passing above Egypt at the time.

Steven Cummer of Duke University said:

“This is a fundamental new discovery about how our planet works…The idea that any planet has thunderstorms that can create antimatter and launch it into space is something out of science fiction. The fact that our own planet is doing it is truly amazing.”

It is already common knowledge that thunderstorms emit gamma rays, (the most energetic form of light), and that gamma rays may create positrons via the process of pair formation.

When a gamma ray that has the right amount of energy interacts with an air atom, energy from the gamma ray becomes converted into matter, one positron and one electron. Scientists, though, wouldn’t have been surprised to see a few positrons accompanying any intense gamma ray burst. The lightning flash detected by the Fermi, however, appeared to have produced about 100 trillion positrons.

This planet constantly gets bombarded by radiation from the sun, as well as cosmic rays from distant however violent events, like powerful supernovae.

Considering the amount of positrons in the beam that was detected by the Fermi, the thunderstorm was briefly creating more radiation in the form of positrons and gamma rays than what hits actually hits this planet’s atmosphere from all other cosmic sources combined.

Duke’s Cummer added:

“We really don’t understand a lot of the details about how lighting works…gives us a very, very important clue as to what’s happening.”