Posted on by Nancy Atkinson

Potential ‘Goldilocks’ Planet Found

A planet 6 times the mass of Earth orbits around the star Gliese 667 C, which belongs to a triple system. Credit: ESO

A new-found planet is in a ‘just-right’ location around its star where liquid water could possibly exist on the planet’s surface. A team of international astronomers have discovered a potentially habitable super-Earth orbiting a nearby star in a habitable zone, where it isn’t too hot or too cold for liquid water to exist. The planet, GJ 667Cc, has an orbital period of about 28 days and with a mass about 4.5 times that of the Earth. The star that it orbits is quite interesting. It is an M-class dwarf star and is a member of a triple star system and appears to be quite different from our Sun, relatively lacking in metallic elements.

The team said this discovery demonstrates that habitable planets could form in a greater variety of environments than previously believed.

“This was expected to be a rather unlikely star to host planets,” said Steven Vogt from UC Santa Cruz, one of the scientists involved in the discovery. “Yet there they are, around a very nearby, metal-poor example of the most common type of star in our galaxy. The detection of this planet, this nearby and this soon, implies that our galaxy must be teeming with billions of potentially habitable rocky planets.”

“This planet is the new best candidate to support liquid water and, perhaps, life as we know it,” said Guillem Anglada-Escudé, from the University of Gottingen in Germany. He was with the Carnegie Institute for Science when the planet was first discovered.

The planet orbits quite close to its parent star at 0.12 astronomical units, which is much closer than Mercury to the Sun. However, the Planetary Habitability Laboratory says the star is much dimmer and provides enough energy for the planet to possibly maintain similar terrestrial temperatures. There’s a caveat, though, that astronomers aren’t sure what the planet’s composition is, because they have not been able to measure its size; therefore, it could be a either a rocky or a gas planet. I would need to have a radius between about 1.7 and 2.2 Earth radii to be a rocky world.

The team used public data from the European Southern Observatory combined with observations from the Keck Observatory in Hawaii and the new Carnegie Planet Finder Spectrograph at the Magellan II Telescope in Chile. To follow up and verify the findings, the team used the radial velocity method to measures the small wobbles in the star’s motion caused by the gravitational tug of a planet.

“With the advent of a new generation of instruments, researchers will be able to survey many M dwarf stars for similar planets and eventually look for spectroscopic signatures of life in one of these worlds,” said Anglada-Escudé.

The star, GJ 667C is 22 light years away. It has much lower abundance of elements heavier than helium, such as iron, carbon, and silicon, as does our Sun. The other two stars (GJ 667A and B) are a pair of orange K dwarfs, with a concentration of heavy elements only 25% that of our Sun’s. Such elements are the building blocks of terrestrial planets so it was thought to be unusual for metal-depleted star systems to have an abundance of low mass planets.

Diagram of the planets orbiting the star GJ 667C. Credit: UC Santa Cruz

GJ 667C had previously been observed to have another super-Earth (GJ 667Cb) with a period of 7.2 days, although this finding was never published. This orbit is too tight, and thus hot, to support life. The new study started with the aim of obtaining the orbital parameters of this super-Earth, and came to find an additional planet.

The new planet receives 90% of the light that Earth receives. However, because most of its incoming light is in the infrared, a higher percentage of this incoming energy should be absorbed by the planet. When both these effects are taken into account, the planet is expected to absorb about the same amount of energy from its star that the Earth absorbs from the Sun. This would allow surface temperatures similar to Earth and perhaps liquid water, but this extreme cannot be confirmed without further information on the planet’s atmosphere.

The team said there is a possibility of other planets in the system, potentially a gas-giant planet and an additional super-Earth with an orbital period of 75 days. However, further observations are needed to confirm these two possibilities.

This is the fourth potentially habitiable extrasolar planet. Three were found in 2011: Gliese 581d, which scientists say is likely a rocky world about 20 ight-years away; HD 85512 b, another planet orbiting in a habitable zone is about 36 light-years away from Earth; and Kepler 22b, about 600 light-years away. Vogt was involved in the discovery of another planet in 2010 (Gliese 581g) in which he said the “chances of life on this planet are 100%,” but other astronomers have cast doubt on whether that planet even exists.

Papers:
The HARPS search for southern extra-solar planets XXXI. The M-dwarf sample, and A planetary system around the nearby M dwarf GJ 667C with at least one super-Earth in its habitable zone (will add link when it becomes available)

Sources: UC Santa Cruz, Carnegie Institute for Science, Planetary Habitability Laboratory

Posted on by Ken Kremer

Inaugural Vega Rocket Poised at Europe’s South American Spaceport

1st Fully assembled Vega on launch pad for Inaugural Flight - February 2012. ESA’s new Vega rocket is now fully assembled on its launch pad. Final preparations are in full swing for the rocket’s inaugural flight as early as February 9 from Europe’s Spaceport in Kourou, French Guiana. Credits: ESA - S. Corvaja

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Final preparations are in full swing for the inaugural flight of Europe’s new light launcher – the Vega booster – from the European Space Agency’s (ESA) Spaceport in Kourou, French Guiana. Launch crews are preparing the new rocket for blastoff as early as Feb 9, 2012 from the new Vega launch site at Kourou.

Vega has been under development for 9 years by ESA and its partners, Italian space agency ASI, French space agency CNES and industry.

The 30 meter tall Vega will join ESA’s venerable Ariane rocket family and the newly inaugurated Soyuz as the third class of booster rockets to launch from ESA’s rapidly expanding South American Spaceport at the Guiana Space Center.

1st Vega Rocket at pad. Credits: ESA - S. Corvaja, 2012

This gives ESA an enormous commercial leap and wide ranging capability to launch all types of satellites from small to big and heavy.

The 4 stage Vega rocket is now fully assembled at the launch pad for the initial qualification flight dubbed VV1. The launch window stretches for a few days beyond Feb. 9.

The Vega VV1 qualification flight will carry 9 satellites to orbit.

The payloads are housed inside the ‘upper composite’ composed of the payload fairing and adapter and were integrated on top of the AVUM fourth stage by pad workers on Jan. 24, who completed and verified all the electrical and mechanical connections and links.

Fully assembled Vega VV01 on pad. Credits: ESA - S. Corvaja, 2012

The satellites aboard include the LARES laser relativity satellite, ALMASat-1 from ASI and seven CubeSats from an assortment of European Universities.

Vega's upper composite, comprising LARES, ALMASat-1, seven CubeSats and the fairing, was transferred to the pad on 24 January and added to the vehicle at Europe's Spaceport in French Guiana. Credits: ESA - M. Pedoussaut, 2012

The main tasks remaining before the maiden flight are the final checkout of the assembled vehicle, the last launch countdown rehearsal and the fuelling of the restartable AVUM 4th stage with liquid propellants.

The Vega launch site is located at the previous ELA-1 complex, originally used for Ariane 1 and Ariane 3 missions and has been rebuilt and upgraded.

Fully assembled Vega VV01 on pad. Credits: ESA - S. Corvaja, 2012

The Vega rocket is specifically designed to fill a market gap in ESA’s satellite launch capabilities, namely the smaller, lightweight science and earth observation satellites.

It can launch payloads ranging from 300 kg to 2500 kg in mass, depending on the customers orbital requirements.

Vega affords ESA full market coverage by complementing the medium and heavy weight payload categories covered by the Soyuz and Ariane V rockets.

1st Fully assembled Vega on launch pad for Inaugural Flight - February 2012. Credits: ESA - S. Corvaja

Watch Universe Today for Vega maiden launch coverage and special launch pictures

Posted on by Nancy Atkinson

Remembering Columbia and Suffering from Survivor’s Guilt

Coumbia Crew - On February 1, 2003, after a 16-day scientific mission, space shuttle Columbia disintegrated during its reentry into the Earth's atmosphere, killing astronauts Rick Husband, William McCool, Michael Anderson, David Brown, Kalpana Chawla, Laurel Clark, and the first Israeli astronaut in space, Ilan Ramon. Credit: NASA

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Across the social networks today, many people were sharing their memories of the Columbia space shuttle accident, which happened 9 years ago, on February 1, 2003. Most all of us have a “where I was and what I was doing” story, but one of the most poignant posts today came from Michael Interbartolo, who works for NASA, and in 2003 was on the Guidance, Navigation, and Control (GNC) Flight Control team for the space shuttle. While he wasn’t in Mission Control when Columbia was lost, he still feels the pain of the accident each year when the anniversary date approaches.

“Every year I struggle with survivor’s guilt,” he wrote on Google+, “and wonder what if I had a time machine?”

In sharing an email he wrote just a few days after the accident, Interbartolo said, “I really feel like we lost 8 members of the family. Columbia was like the family dog who had gotten old, but she was still loyal and true and you knew you could count on her…It hurts to lose friends like this. I didn’t know any of them personally other than a meeting here and there or maybe in a sim together, but right now it feels like a big part of me is gone.”

Michael Interbartolo in Mission Control. Image courtesy of Michael Interbartolo

Interbartolo continued, expressing his love of his job: “To work here at mission control is a wonder each and every day and really is the stuff dreams are made of. For some this is just a job, others share my enthusiasm and love for the program, but everyone is dedicated 110% each day to bring each astronaut safely home every mission and when they don’t then we all feel the pain and anguish like right now.”

With February 1st here again, Interbartolo says he repeatedly goes through what he and others in Mission Control possibly could have done differently. “What if I could go back in time to try and save Columbia and her crew? Now with 9 years of experience since the accident, the Shuttle put out to pasture and no access to space on our own, changing that point in time almost seems more important.”

Interbartolo came up with four different scenarios of what possibly could happen if he had a time machine:

Debris from the space shuttle Columbia streaks across the sky near Tyler, Texas.

Scenario One – Day of Deorbit:

From the time the Entry team came on console to GO For deorbit burn, it is typically about 6 hours. So it would be the “12 Angry Men” scenario, bit by bit trying to convince the team to wave off the burn… Sure it would make for a tension filled movie, but reality is waving off the burn and convincing them to open the payload bay doors, activate the robotic arm and look solves nothing, probably. The crew would know they were dead; they could put the orbiter into a powerdown, but time would be short with limited consumables to come up with a repair that would work. In Hollywood movies sure, in real life? Too risky to use the Time Machine here, we need to go further back to ensure success.

A shower of foam debris after the impact on Columbia?s left wing. The event was not observed in real time. Credit: NASA

Scenario Two – Flight Day Two:

Images start coming in showing the foam strike, but as history has shown the management team was not listening and there were plenty of missed opportunities. So how could I convince them any better. It would take a few days, then get the DOD to use their assets to image the damage and if I hadn’t gotten the powerdown of the orbiter we still only have limited time plus how to repair? a Spacewalk is possible but we didn’t have wing leading edge or tile repairs kits until after the Columbia Accident so now we would have to come up with it on the fly probably stuffing maybe water bags, a space suit or something into the hole, cold soaking the wing and hope the turbulent boundary layer and plasma are kept at bay. time is short and this is still pretty risky and certainly a lot more engineering effort than fitting a square LiOH into a round hole (Apollo 13 issue). Need to go further back.

Columbia on the launchpad before the STS-107 mission. Credit: NASA

Scenario Three – PreLaunch No GO:

Where to jump in, foam had been an issue since STS-1 and was not seen as a concern. Heck even after Columbia we still had foam issues and had to redesign the Ice Frost Ramps and other bracket interfaces. Convincing the team to wave off prelaunch would require debris transport analysis to show foam could strike at high speed on the wings plus impact testing to show how much damage it would be. So now we grounded the fleet, worked on the foam, augmented ascent imagery assets/analysis, but we would still need a boom sensor, inspection techniques and repair options. A fundamental shift in how we do business and think about foam, something that only really happened because of Columbia, this would require overcoming the “Failure of Imagination” mindset. Hmm maybe we need to go back further.

Columbia landing at Edwards Air Force Base on the first shuttle mission, STS-1. Credit: NASA

Scenario Four – Designing the STS:

All the way back to the 70’s, reusable winged system side mounted on a big tank of foam that needed a 1500 nm cross range for once around polar DOD flights from Vandenburg. So it comes down to Only Nixon can save Columbia by scrapping the design and coming up with something else. If we can mitigate the foam loss or get away from fragile Reinforced Carbon Carbon wings in the danger zone then maybe Columbia could be saved (and maybe we can fix the O-ring and save Challenger as well). So now we trade 7 lives for 30 years of shuttle operations, launching telescopes/spacecraft, and building the space station. Could we come up with another heavy lift design that can go from rocket to space truck to orbiting space station to flying brick? This is the Kobayashi Maru for Time Traveler and the Space Shuttle Program, do I risk all the discoveries, knowledge, science and a space station by fundamentally changing the design to save Columbia? Maybe February 1st really is a Fixed Point in Time and Space.

In the end, Interbartolo said, there is no time machine; the Columbia and her crew are still lost, the Shuttle completes her mission of building the space station and now we have the gap of not being able to launch our own astronauts.

“There will be future loss of life in the pursuit of space because it is a harsh and unforgiving environment with objects travelling in excess of 17,500 mph and there will always be Unknown, Unknowns,” Interbartolo wrote. “But as Gus (Grissom)said, “The conquest of space is worth the risk,’ and through the tragedies of Apollo 1, Challenger and Columbia we are reminded that we must be vigilant and always attentive to the dangers of spaceflight; never accepting success as a substitute for rigor in everything we do. We must always be aware that suddenly and unexpectedly we may find ourselves in a role where our performance has ultimate consequences. And finally we must recognize that the greatest error is not to have tried and failed, but that in the trying we do not give it our best effort.”

Universe Today thanks Michael Interbartolo for allowing us to share his memories and his grief.

Posted on by Amy Shira Teitel

Looks Like We’re Still Looking for Earthly Life Forms on Other Planets

GFAJ-1, the bacterium found in California's Lake Mono. Image credit: Science/AAAS

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In late 2010, NASA set the Internet buzzing when it called a press conference to discuss an astrobiological finding that would impact the search for extraterrestrial life. Many speculated that some primitive life had been found on Mars or one of Saturn’s moons. But the evidence was found on Earth; a strain of bacteria in California’s Lake Mono that had arsenic in its genetic structure. The discovery implied that life could thrive without the elements NASA typically looks for, mainly carbon and phosphorous. But now, a new study challenges the existence of arsenic-based life forms. 

The 2010 paper announcing arsenic based life, “Arsenic-eating microbe may redefine chemistry of life,” was written by a team of scientists led by Felisa Wolfe-Simon. The paper appeared in Science and refuted the long-held assumption that all living things need phosphorus to function, as well as other elements including carbon, hydrogen, and oxygen.

Lake Mono, as seen from Space. Image credit: NASA

The phosphate ion plays several essential roles in cells: it maintains the structure of DNA and RNA, it combines with lipids to make cell membranes, and it transports energy within the cell through the molecule adenosine triphosphate (ATP). Finding a bacteria that uses normally poisonous arsenic in the place of phosphate shook up the guidelines that have structured NASA’s search for life on other worlds.

But microbiologist Rosie Redfield didn’t agree with Wolfe-Simon’s article and published her concerns as technical comments in subsequent issues of Science. Then, she put Wolfe-Simon’s results to the test. She led a team of scientists at the University of British Columbia in Vancouver and tracked her progress online in the name of open science.

Redfield followed Wolfe-Simon’s procedure. She grew GFAJ-1 bacteria, the same strain found in Lake Mono, in a solution of arsenic with a very small amount of phosphorus. She then purified DNA from the cells and sent the material to Princeton University in New Jersey. There, graduate student Marshall Louis Reaves separated the DNA into fractions of varying densities using caesium chloride centrifugation. Caesium chloride, a salt, creates a density gradient when mixed with water and put in a centrifuge. Any DNA in the mixture will settle throughout the gradient depending on its structure. Reaves studied the resulting DNA gradient using a mass spectrometer to identify the different elements at each density. He found no trace of arsenic in the DNA.

Redfield’s results aren’t by themselves conclusive; one experiment isn’t enough to definitively disprove Wolfe-Simon’s arsenic-life paper. Some biochemists are eager to continue the research and want to figure out the lowest possible level of arsenic that Redfield’s method could detect as a way of determining exactly where arsenic from the GFAJ-1 DNA ends up on a caesium chloride gradient.

Dr. Redfield. Image credit: M. Dee/Nature

Wolfe-Simon is also not taking Redfield’s results as conclusive; she is still looking for arsenic in the bacterium. “We are looking for arsenate in the metabolites, as well as the assembled RNA and DNA, and expect others may be doing the same. With all this added effort from the community, we shall certainly know much more by next year.”

Redfield, however, isn’t planning any follow-up experiments to support her initial findings. “What we can say is that there is no arsenic in the DNA at all,” she said. “We’ve done our part. This is a clean demonstration, and I see no point in spending any more time on this.”

It’s unlikely that scientists will conclusively prove or disprove the existence arsenic-based life anytime soon. For the time being, NASA will likely confine its search for extraterrestrial life to phosphorus-dependent forms we know exist.

Source: nature.com

Posted on by Nancy Atkinson

GRAIL Sends Back First Video of the Moon’s Far Side

A first look from GRAIL, showing the lunar far side! A camera aboard ‘Ebb’ — one of NASA’s twin Gravity Recovery And Interior Laboratory (GRAIL) lunar spacecraft has returned its first unique view of the far side of the Moon. The camera is the MoonKAM, which is part of a special program for students to study the Moon.

“The quality of the video is excellent and should energize our MoonKAM students as they prepare to explore the Moon,” said Maria Zuber, GRAIL principal investigator.
Continue reading “GRAIL Sends Back First Video of the Moon’s Far Side”

Posted on by Ray Sanders

Help Support a ‘New Horizons’ U.S. Postage Stamp!

Concept art for a New Horizons postage stamp. Image Credit: Dan Durda/Southwest Research Institute

[/caption]Today the New Horizons mission team, along with Principal Investigator Alan Stern have unveiled their proposal for a U.S Postage stamp, to honor the first mission to Pluto.

The current concept art for the stamp was done by Dan Durda, a space scientist and artist at The Southwest Research Institute. Durda’s work has appeared on the New Horizons website and in other locations. If the stamp is approved, it would be the successor to a U.S. postage stamp issued in 1990 that labeled Pluto as “Not Yet Explored.”

“You can help make this happen.” says Stern.

Since it can take several years for a proposed stamp to be approved by the U.S. post office, the mission team launched an internet petition today. The team plans to submit petitioners’ names along with their formal proposal, with the hopes that the stamp will be approved and printed in time to celebrate the New Horizons fly-by of Pluto in 2015.

Stern added, “We’re asking people to sign the petition, because the post office considers not just the merits of a new stamp proposal, but also whether it is supported by a significant number of people. This is a chance for us all to celebrate what American space exploration can achieve though hard work, technical excellence, the spirit of scientific inquiry, and the uniquely human drive to explore.”

Artist's impression of New Horizons' encounter with Pluto and Charon. Credit: NASA/Thierry Lombry
You can help by signing the petition urging the post office’s Citizen Stamp Advisory Committee to recommend a New Horizons stamp to the postmaster general.

The New Horizons team encourages people signing the petition to also tell their friends, family members, Facebook friends, Google plusketeers, and Twitter followers to sign as well!

The text of the petition reads as follows:

Greetings,

I just signed the following petition addressed to: Citizens’ Stamp Advisory Committee.

—————-
The nation has an opportunity to honor a truly exemplary accomplishment of humankind in general, and the U.S. space program in particular, with a new U.S. postage stamp in 2015 honoring the flyby and reconnaissance of the Pluto system by NASA’s New Horizons spacecraft.

New Horizons lifted off in January 2006 aboard a U.S. Atlas V rocket, the fastest spacecraft ever launched. In fact, New Horizons crossed the orbit of the Moon in just nine hours – almost 10 times quicker than the Apollo lunar missions. Since then, New Horizons has been speeding toward Pluto – more than three billion miles from Earth — covering nearly one million miles a day!

New Horizons will make its closest approach to Pluto and its family of moons on July 14, 2015, 50 years to the day after Mariner 4 made the first successful flyby of Mars.

With the New Horizons flyby of Pluto, the U.S. space program will complete the first era of planetary reconnaissance, a profoundly inspiring feat of lasting historical significance. Moreover, the Pluto flyby will represent the first exploration of the Kuiper Belt, the first exploration of a double planet, the first exploration of an ice dwarf planet, and the farthest object ever explored in space.

Join the mission team in asking the U.S. Postal Service to commemorate the historic achievements of New Horizons by signing this petition in support of a new postage stamp, supplanting the 1990 U.S. stamp that described Pluto simply as “Not Yet Explored.”

The petition urges the Citizen Stamp Advisory Committee to recommend to the Postmaster General a stamp in honor of New Horizons.

Let’s celebrate what humans can achieve though hard work, technical excellence, scientific inquiry and the uniquely human spirit of exploration.
—————-

Sincerely,

[Your name]

Sign the petition at: http://www.change.org/petitions/usps-honor-new-horizons-and-the-exploration-of-pluto-with-a-usps-stamp

If you’d like to learn more about the New Horizons mission, visit: http://pluto.jhuapl.edu/index.php

Source: New Horizons Mission Updates

Posted on by Nancy Atkinson

Hitchcock Haunts a Nebula

The star-forming region NGC 3324. The intense radiation from several of NGC 3324's massive, blue-white stars has carved out a cavity in the surrounding gas and dust. The ultraviolet radiation from these young hot stars also cause the gas cloud to glow in rich colors. Credit: ESO

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First impression after seeing this new image of NGC 3324? It’s Alfred Hitchcock, bulbous nose and all (see image below for comparison). The right edge of the wall of gas and dust in this star-forming region really bears a strong resemblance to the famous profile of the British film director and producer, notorious for his thriller movies from the 1940’s through the 1970’s.

NGC 3324 is located in the southern constellation of Carina, roughly 7500 light-years from Earth. It is on the northern outskirts of the chaotic environment of the Carina Nebula. All the gas and dust here fueled a burst of star birth several millions of years ago and led to the creation of several hefty and very hot stars that are prominent in the new picture.

Alfred Hitchcock. Via iwatchstuff.com

A nickname for the NGC 3324 region is the ‘Gabriela Mistral Nebula,’ after the Nobel Prize-winning Chilean poet but I think I’ll start a petition to call it the Hitchcock Nebula. Hitchcock liked to make cameo appearances in his own movies, and perhaps he is making a pareidoliaic guest appearance here.

The new image of NGC 3324 was taken with the Wide Field Imager on the the European Southern Observatory’s 2.2-metre telescope at the La Silla Observatory in Chile. Read more about it on the ESO website.

Posted on by Tammy Plotner

Russia Will Begin Hunt For Extrasolar Planets

Russia to Start Own Search for Extrasolar Planets - Photo: Paul A. Kempton

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Located just south of Saint Petersburg on Pulkovo Heights, one of the greatest Russian Observatories of all times – the Pulkovo Observatory – is about to embark on a very noble study. According to the head of the Institute for Space Research, Lev Zelyony, the Soviet telescopes are about to turn their eyes towards deep skies in search of extrasolar planets. “Scientists from the Pulkovo Observatory are planning to use ground-based instruments to study the transit of planets around their parent stars,” Zelyony said at a roundtable meeting at RIA Novosti headquarters in Moscow.

The observatory was absolutely state-of-the-art when it opened for business in 1839 and employed Wilhelm von Struve as its director. It houses some of the largest refractor telescopes in the world, including a 38-cm (15 in.) aperture refractor and a 30-inch (76 cm) refractor – both built by Alvan Clarke and Sons. Fifty years later, they added an astrophysical laboratory, a mechanical workshop and installed one of Europe’s largest lensed telescope, a 76-cm refractor (30 inch). Later additions to the observatory included a Littrow spectrograph and horizontal solar telescope and the facility blossomed into a world leader in stellar spectroscopy, cataloging and more. Modern improvements include astrograph equipment, an interferometer, radio telescope and even an additional 65-cm (26-inch) refractor. The Pulkovo Observatory is up to the task.

Pulkovo Observatory 2004 - Credit: Vladimir Ivanov

The hunt for exoplanets is one of the most popular aspects of modern astronomy and one of the fastest growing fields. In less than 25 years, 755 and an ever-increasing number of planets have been cataloged… and the research just doesn’t end. The United States Kepler Mission and French CoRoT space telescope have had their share of fun, but using a ground-based telescope could also be a viable source of planet detection, Zelyony said. He also cited the example of the Hungarian Automated Telescope Network (HATNet) which so far has discovered 29 exoplanets. By using the transit detection method, the Russian astronomers are eager to begin observations where a small change in magnitude could mean a big change in the way their telescopes perceive the stars.

“It is an interesting research, which should be pursued,” Zelyony said. “It will also help us look at our Solar System from a different perspective.”

Original Story Source: Rionovosti News Release.

Posted on by Nancy Atkinson

2012 BX34: Behind the Scenes in the Discovery of a Near Earth Asteroid

The images in which asteroid 2012 BX34 was discovered. Images are from Jan. 25, 2012 10:30 UT. Credit: Alex Gibbs, Catalina Sky Survey/University of Arizona

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Several blockbuster movies, television shows and commercials have depicted the discovery of an asteroid heading towards Earth and usually, somehow, impending doom is averted. But how do the discoveries of Near Earth Objects really happen? Asteroid 2012 BX34 buzzed by Earth last week, and even though this small asteroid was never considered a threat to Earth, its discovery still piqued the interest of the public. It was discovered by Alex Gibbs, an astronomer and software engineer from the Catalina Sky Survey. Universe Today asked Gibbs to share his experiences of being an asteroid hunter and what it was like to find this latest NEO that made the Top-20 list of closest approaches to Earth.

The Catalina Sky Survey is a research program at the University of Arizona and is part of the Spaceguard Survey, a NASA project to discover and catalog Earth-approaching and Potentially Hazardous Asteroids (PHAs).

When astronomers look through telescopes, asteroids don’t look much different from stars – they are just points of light. But these points of light are moving; however they are moving slow enough that to detect the motion, astronomers take a series of images, usually four images spaced 10-12 minutes apart.

Then, the observers run specialized software to examine their images for any star-like objects that are moving from one image to the next. The software removes any candidates that correspond to known objects or main-belt asteroids.

Gibbs said the software has a low detection threshold to avoid missing anything, so the observer looks over what the software found and determines which are real. The remaining objects that the software determines could be interesting are then sent in to the Minor Planet Center (MPC) at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, for the team or others to follow up.

The Catalina Sky Survey's Schmidt Telescope. Image courtesy Catalina Sky Survey

Gibbs said his discovery images of 2012 BX34 were taken at 10:30 UT (3:30 am in Tucson) on January 25, 2012. He was using a Schmidt telescope on Mount Bigelow. At the time, the object was 1.8 million km away, moving 1.15 degrees/day across the sky, and at 20th magnitude.

On the night of discovery, Gibbs said 2012 BX34 seemed just like most of the NEOs they find. But something unusual happened the following night.

“No one seemed to be able to find it,” Gibbs said via email. “That happens sometimes, but it should have been pretty easy for the observatories that were looking. When my colleague, Rik Hill, found a ‘new’ object nearby I was suspicious that it might be the same object. The object’s rapid increase in brightness and apparent motion had made it difficult to recognize as the same object.”

When Gibbs put the two observations together he could tell they were the same object. But more importantly, he also could tell the object was going to come fairly close to Earth.

“That’s when I emailed the MPC to point out that they were the same object,” Gibbs said.

Asteroid Passing in Front of Galaxies Before Passing Earth from Alex Gibbs on Vimeo.

Even though this is what Gibbs does for a living, certainly there must be a certain thrill (or butterflies in the stomach) when it is realized one of these NEOs is coming fairly close to Earth?

“We realized it was going to come pretty close, but wouldn’t impact,” Gibbs said. “I knew it was small enough that it would disintegrate if it did, so although I was excited, I was also a little disappointed that it wasn’t going to put on more of a show. But I definitely prefer this to it being TOO flashy!”

The software at the MPC also figured out this asteroid was coming close, and just like in the movies, astronomer Gareth Williams, associate director of the MPC, was aroused from his sleep in the middle of the night by a pager message. But, said Williams in an interview with the BBC, “when I saw the miss distance was going to be 10 Earth radii, I said ‘that’s too far for me to get up,’ so I rolled over and went back to sleep.”

“That explains why the emails I exchanged with him later on were so short,” Gibbs said.

Captures of asteroid 2012 BX34 moving through the field of background stars. Credit: Alex Gibbs/Catalina Sky Survey.

At its closest approach, on January 27 15:15 UT, 2012 BX34 was 59,600 km from the Earth’s surface, moving 729 deg/day, appearing at 14th magnitude, which is 250 times brighter than when Gibbs first saw it.

Gibbs said it is common for discoveries to be followed up by others astronomers, though it’s not a rigid practice.

“Whenever we find something moving in an ‘interesting’ way we send it to the Minor Planet Center, as do all the other surveys,” he said. “The MPC publishes the objects on their public NEO Confirmation Page. Various parties then follow the objects up, both pros and amateurs. Whether an object is deemed interesting or not is primarily determined by software that looks at the motion and brightness, though we can often tell when we see it. We also submit anything that appears to have cometary features.”

As of January 29, 2012, 8,648 Near-Earth objects have been discovered, with about 840 of these NEOs being asteroids with a diameter of approximately 1 kilometer or larger. Also, 1,284 of these NEOs have been classified as PHAs.

“NEOs are ones that come within 1.3 AU of the Sun (since the Earth is at 1 AU it means they pass through our neighborhood),” Gibbs said. “ PHAs are those that are larger than about 150 m (500 ft) and come within 0.05 AU of Earth’s orbit, so that at some point in the future they may cross paths.” (See more info on PHAs here)

“The large asteroids are much brighter than objects like 2012 BX34,” Gibbs said. “We see them as they orbit the Sun, and can determine if they are likely to come close to the Earth at some point. That gives us a lot more time to do something about an impact from the most dangerous asteroids. However, we ought to be doing more to catalog all the asteroids that could potentially take out a city or cause a tsunami. We are finding them now, but not fast enough. An asteroid impact is one of the few predictable and potentially preventable natural disasters.”

Even though asteroid 2012 BX34 was one of the top-20 closest approaches by an asteroid, its size made it a non-issue. While bus-sized sounds pretty big, this is small enough that it would break apart and burn up in the atmosphere. Instead, it passed by harmlessly.

“But a close fly-by like this one serves to remind people that asteroids of all sizes do come by the Earth,” said Gibbs. “We need to be vigilant.”

As for Gibbs, he is back at his job of asteroid hunting, and tonight will be scanning the skies from a larger telescope on Mt. Lemmon in Arizona.

More info:
Catalina Sky Survey
The telescopes and facilities of the CSS
Minor Planet Center
Asteroid and Comet Impact Hazards website from NASA
NASA’s Near Earth Object Program

Posted on by Tammy Plotner

New Study Reveals Little Ice Age Triggered By Volcanism

Gifford Miller collects vegetation samples on Baffin Island. (Photo courtesy University of Colorado Boulder.)

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In a study led by the University of Colorado Boulder with co-authors at the National Center for Atmospheric Research (NCAR) and other organizations, researchers may have possibly found evidence the “Little Ice Age” may have had ties to an unusual era of volcanic activity… one that lasted for about 50 years. In just five decades, four massive tropical volcanic eruptions managed to take Earth’s entire environment and put it on ice. Somewhere near the years between 1275 and 1300 A.D., these eruptions caused some very cool summer weather in the northern hemisphere which triggered an expansion of sea ice that – in turn – weakened Atlantic currents. However, it didn’t weaken the already cool climate. It strengthened it.

The international study was done in layers – like a good cake – but instead of sweet frosting, it was a composite look at dead vegetation, ice and sediment core data. By engaging highly detailed computer climate modeling, scientists are now able to have a strong theory of what triggered the Little Ice Age.. a theory which begins with decreased summer solar radiation and progresses through erupting volcanoes. Here planet-wide cooling could have been started by sulfates and other aerosols being ejected into our atmosphere and reflecting sunlight back into space. Simulations have shown it could have even been a combination of both scenarios.

“This is the first time anyone has clearly identified the specific onset of the cold times marking the start of the Little Ice Age,” says lead author Gifford Miller of the University of Colorado Boulder. “We also have provided an understandable climate feedback system that explains how this cold period could be sustained for a long period of time. If the climate system is hit again and again by cold conditions over a relatively short period—in this case, from volcanic eruptions—there appears to be a cumulative cooling effect.”

“Our simulations showed that the volcanic eruptions may have had a profound cooling effect,” says NCAR scientist Bette Otto-Bliesner, a co-author of the study. “The eruptions could have triggered a chain reaction, affecting sea ice and ocean currents in a way that lowered temperatures for centuries.” The team’s research papers will be published this week in Geophysical Research Letters. Members of the group include co-authors from the University of Iceland, the University of California Irvine, and the University of Edinburgh in Scotland. The study was funded in part by the National Science Foundation, NCAR’s sponsor, and the Icelandic Science Foundation.

“Scientific estimates regarding the onset of the Little Ice Age range from the 13th century to the 16th century, but there is little consensus,” Miller says. It’s fairly clear these lower temperatures had an impact on more southerly regions such as South American and China, but the effect was far more clear in areas such as northern Europe. Glacial movement eradicated populated regions and historical images show people ice skating in places known to be too warm for such solid freezing activities before the Little Ice Age.

“The dominant way scientists have defined the Little Ice Age is by the expansion of big valley glaciers in the Alps and in Norway,” says Miller, a fellow at CU’s Institute of Arctic and Alpine Research. “But the time in which European glaciers advanced far enough to demolish villages would have been long after the onset of the cold period.”

By employing the technique of radiocarbon dating, approximately 150 plant specimens, complete with roots, were gathered from the receding edges of ice caps located on Baffin Island in the Canadian Artic. In these samples they found evidence of a “kill date” which ranged between 1275 and 1300 A.D. This information led the team to surmise the plants were quickly frozen and then just as quickly encased in solid ice. A second documented kill date occurred about 1450 A.D. showing another major event. To further flesh out their findings, the research team took sediment sample cores from a glacial lake which is linked to the mile-high Langikull ice cap. These important samples from Iceland can be reliably dated back as far as 1,000 years and the results showed a sudden increase in ice during the late 13th century and again in the 15th. Thanks to these techniques which rely on the presence tephra deposits, we know these climate cooling events occurred as a result of volcanic eruptions.

“That showed us the signal we got from Baffin Island was not just a local signal, it was a North Atlantic signal,” Miller says. “This gave us a great deal more confidence that there was a major perturbation to the Northern Hemisphere climate near the end of the 13th century.”

What brought the team to their final conclusions? Through the use of the Community Climate System Model developed by scientists at NCAR and the Department of Energy with colleagues at other organizations, they were able to simulate the impact of volcanic cooling on the extent and mass of Artic sea ice. The model painted a portrait of what could have occurred from about 1150 to 1700 A.D. and showed that some large scale eruptions could have impacted the northern hemisphere if they happened within a close time frame. In this scenario, the long term cooling effect could have expanded the Artic Sea ice to the point where it eventually met – and melted – in the North Atlantic. During the modeling, the solar radiation was set at a constant to show ” the Little Ice Age likely would have occurred without decreased summer solar radiation at the time.” concluded Miller.

Original Story Source: Univsersity Corporation for Atmospheric Research.