Universe Today

July 7, 2013December 23, 2015 by Ken Kremer

Opportunity rover marks Magic Moment on 10th Year since Launch with Mountain Goal in View

Opportunity rover’s view across Botany Bay to Solander Point – her next destination – as NASA celebrates 10 Years since blastoff for Mars on July 7, 2003. The rover will climb up Solander Point because it which may harbor clay minerals indicative of a past Martian habitable environment. This pancam mosaic was assembled from raw images taken on Sol 3348 (June 24, 2013.
Credit: NASA/JPL/Cornell/ASU/Marco Di Lorenzo/Ken Kremer (kenkremer.com)[/caption]

Today, NASA’s Opportunity rover marks a magical moment celebrating 10 years since launching to Mars on July 7, 2003 and with her impending Mountain destination filling the camera’s eye view.

The now legendary robot has vastly exceeded everyone’s expectations. Back in 2003 the science team promised us a mere 90 day ‘warranty’ following the suspenseful airbag landing on Jan. 24, 2004 at Meridiani Planum.

Today is Martian Day (or Sol) 3360. That amounts to a life expectancy and exploration ‘bonus’ of more than 37 times beyond the design lifetime.

Launch of NASA’s 2nd Mars Exploration Rover, Opportunity, aboard a Delta II Heavy rocket to Mars on July 7, 2003 at 11:18 p.m. EDT from Pad 17-B at Cape Canaveral Air Force Station, Fla. Credit: NASA

Opportunity’s twin sister Spirit blasted off three weeks earlier in June 2003 and continued functioning until 2010.

“I never thought we’d achieve nine months!” Principal Investigator Prof. Steve Squyres of Cornell University told me recently on the occasion of the rovers 9th anniversary on Mars in January 2013.

As you read this, the now decade old rover Opportunity is blazing a trail toward’s the oldest geological deposits she has ever explored – at a place called Solander Point, a raised ridge along the eroded rim of huge Endeavour Crater.

Opportunity has surpassed the halfway point in the traverse from the rim segment she has explored the past 22 months at ‘Cape York’ to her next rim segment destination at Solander.

From tip to tip, Cape York and Solander Point lie 1.2-mile (2-kilometer) apart along the western rim of Endeavour Crater. Both are raised portions of 14-mile-wide (22-kilometer-wide) Endeavour.

The rover has less than half a mile (800 meters) to go to finish the Martian dash from one rim segment to the next across an area called ‘Botany Bay’.

This view from July 2, 2013 (Sol 3355) shows the terrain that NASA's Mars Exploration Rover Opportunity is crossing in a flat area called "Botany Bay" on the way toward "Solander Point," which is visible on the horizon. Credit: NASA/JPL-Caltech — This view from July 2, 2013 (Sol 3355) shows the terrain that NASA’s Mars Exploration Rover Opportunity is crossing in a flat area called “Botany Bay” on the way toward “Solander Point,” which is visible on the horizon. Credit: NASA/JPL-Caltech

“We are making very good progress crossing ‘Botany Bay,’ said John Callas of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., who is project manager for the mission now entering its 2nd decade.

The flat terrain of fractured, light-toned bedrock is devoid of treacherous dunes and is easy to drive across, almost like a highway, which simplifies the daily planning by the rovers Earthly handlers.

“The surface that Opportunity is driving across in Botany Bay is polygonally fractured outcrop that is remarkably good for driving,” said Brad Joliff, an Opportunity science team member and long-term planner at Washington University in St. Louis. “The plates of outcrop, like a tiled mosaic pavement, have a thin covering of soil, not enough to form the wind-blown ripples we’ve had to deal with during some other long treks. The outcrop plates are light-toned, and the cracks between them are filled with dark, basaltic soil and our old friends the ‘blueberries.”

The “blueberries” are hematite-rich, erosion-resistant concretions about the size of BB’s that Opportunity discovered when she first opened her eyes at her Eagle crater landing site. During the multi year crater hopping tour that ensued, the rover continued finding patches of blueberries all the way to Endeavour crater.

1st color panorama taken by Opportunity after landing inside Eagle Crater on Jan. 24, 2004. Credit: NASA/JPL/Cornell

Opportunity is expected to arrive at Solander’s foothills sometime in August – before the onset of the next southern hemisphere Martian winter, her 6th altogether.

Opportunity will scale Solander to continue the science quest in search of additional evidence of habitable environments with the chemical ingredients necessary to sustain Martian microbial life.

“Right now the rover team is discussing the best way to approach and drive up Solander,” Ray Arvidson told Universe Today. Arvidson is the mission’s deputy principal scientific investigator from Washington University in St. Louis, Mo.

‘Solander Point’ offers roughly about a 10 times taller stack of geological layering compared to ‘Cape York.’

Solander also offers north facing slopes where Opportunity’s solar wings can more effectively soak up the sun’s rays to generate life giving electrical power.

The robot remains in excellent health.

The total driving distance exceeds 23 miles (37 kilometers). She has snapped over 181,000 images.

Meanwhile on the opposite side of Mars at Gale Crater, Opportunity’s younger sister rover Curiosity also discovered a habitable environment originating from a time when the Red Planet was far warmer and wetter billions of years ago.

And like Opportunity, Curiosity is also trekking towards a mountain rich in sedimentary layers, hoping to unveil the mysteries of Mars past.

Ken Kremer

Opportunity captures spectacular panoramic view ahead to her upcoming mountain climbing goal, the raised rim of “Solander Point” at right, located along the western edge of Endeavour Crater. It may harbor clay minerals indicative of a habitable zone. The rise at left is "Nobbys Head" which the rover just passed on its southward drive to Solander Point from Cape York. This pancam photo mosaic was taken on Sol 3335, June 11, 2013 shows vast expanse of the central crater mound and distant Endeavour crater rim. Credit: NASA/JPL/Cornell/ASU/Marco Di Lorenzo/Ken Kremer (kenkremer.com) See full panoramic scene below — Opportunity captures spectacular panoramic view ahead to her upcoming mountain climbing goal, the raised rim of “Solander Point” at right, located along the western edge of Endeavour Crater. It may harbor clay minerals indicative of a habitable zone. The rise at left is “Nobbys Head” which the rover just passed on its southward drive to Solander Point from Cape York. This pancam photo mosaic was taken on Sol 3335, June 11, 2013 shows vast expanse of the central crater mound and distant Endeavour crater rim. Credit: NASA/JPL/Cornell/ASU/Marco Di Lorenzo/Ken Kremer (kenkremer.com)

Traverse Map for NASA’s Opportunity rover from 2004 to 2013. This map shows the entire path the rover has driven during more than 9 years and over 3360 Sols, or Martian days, since landing inside Eagle Crater on Jan 24, 2004 to current location heading south to Solander Point from Cape York ridge at the western rim of Endeavour Crater. Credit: NASA/JPL/Cornell/ASU/Marco Di Lorenzo/Ken Kremer — Traverse Map for NASA’s Opportunity rover from 2004 to 2013
This map shows the entire path the rover has driven during more than 9 years and over 3360 Sols, or Martian days, since landing inside Eagle Crater on Jan 24, 2004 to current location heading south to Solander Point from Cape York ridge at the western rim of Endeavour Crater. Credit: NASA/JPL/Cornell/ASU/Marco Di Lorenzo/Ken Kremer

July 6, 2013December 23, 2015 by Jason Major

New Desktop Image Alert: The Moon Over Earth

If you’re like me, you don’t change your computer’s desktop background nearly often enough… especially not considering all the fantastic space images that get released on an almost daily basis. But this picture, shared a couple of weeks ago by NASA’s Marshall Space Flight Center on their Flickr stream, really should inspire you to fix that. (I know it did for me!)

Captured by an Expedition 28 crew member aboard the International Space Station, this beautiful image shows a crescent-lit Moon seen through the upper layers of Earth’s atmosphere.

As it circles the globe, the ISS travels an equivalent distance to the Moon and back in about a day, making an excellent platform for viewing the Earth and its atmosphere. This photo shows the limb of Earth near the bottom transitioning into the orange-colored troposphere, the lowest and most dense portion of the Earth’s atmosphere. The troposphere ends abruptly at the tropopause, which appears in the image as the sharp boundary between the orange- and blue- colored atmosphere. Silvery-blue noctilucent clouds extend far above the Earth’s troposphere.

Expedition 28 began on May 23, 2011, with a crew consisting of Andrey Borisenko, Ron Garan, Alexander Samokutyaev, Sergei Volkov, Mike Fossum, and Satoshi Furukawa.

Image credit: NASA (Source)

July 5, 2013December 23, 2015 by Elizabeth Howell

‘Avalanche’ Risk Higher Than Thought For Asteroid Landings: Study

Landing on asteroids will be a risky endeavor, perhaps aggravated by changes in asteroid dust when it's touched. Credit: NASA Near Earth Object Program

Imagine plunking your spacecraft down on an asteroid. The gravity would be small. The surface would be uneven. The space rock might be noticeably spinning, complicating your maneuvering.

Humans have done it with robotic spacecraft before. The first time was in 2001, when NASA made a stunning landing with the NEAR Shoemaker spacecraft on Eros — using a craft that was not even designed to reach the surface. A new study, however, portrays getting close to these space rocks as perhaps even more hazardous than previously thought.

An experiment done aboard a “Vomit-Comet” like airplane, which simulates weightlessness, suggests that dust particles on comets and asteroids may be able to feel changes in their respective positions across far larger distances than on Earth.

“We see examples of force-chains everywhere. When you pick an orange from a pile in a supermarket, some come away easily, but others bring the whole lot crashing down. Those weight-bearing oranges are part of a force-chain in the pile,” stated Naomi Murdoch, a researcher at the Higher Institute of Aeronautics and Space (Institut Supérieur de l’Aéronautique et de l’Espace) in Toulouse, France.

Naomi Murdoch and Thomas-Louis de Lophem in zero gravity alongside the AstEx experiment. Credit: A. Le Floc’h, ESA — Naomi Murdoch and Thomas-Louis de Lophem in a zero gravity environment aboard a parabolic airplane, alongside the AstEx experiment. Credit: A. Le Floc’h, ESA

“One important aspect of such chains is that they give a granular material a ‘memory’ of forces that they have been exposed to. Reversing the direction of a force can effectively break the chain, making the pile less stable.”

The Asteroid Experiment Parabolic Flight Experiment (AstEx) experiment was designed by Murdoch, Open University’s Ben Rozitis, and several collaborators from The Open University, the Côte d’Azur Observatory and the University of Maryland. It had a cylinder with glass beads inside of it, as well as a rotating drum at the heart.

Stacked photo of the grains in the Asteroid Experiment (AstEx). Credit: AstEx team

In 2009, when they were postgraduate students, Murdoch and Rozitis took their contraption on board an Airbus A300, which flew parabolas to simulate microgravity while the aircraft falls from its greatest height.

During this time, the inner drum spun up for 10 seconds and then the rotational direction was reversed. What happened was tracked by high-speed cameras. Later, the researchers analyzed the movement of the beads with a particle-tracking program.

The researchers found that particles at the edge of the cylinder (the closest analog to low-gravity environments) moved more than those in similar environments on Earth. Those closer to the center, however, were not as greatly affected.

“A lander touching down on the surface on one side of a small, rubble-pile asteroid could perhaps cause an avalanche on the other side, by long-range transmission of forces through chains It would, however, depend on the angle and location of the impact, as well as the history of the surface – what kind of memories the regolith holds,” said Murdoch.

Check out more details of the experiment in the June 2013 issue of the Monthly Notices of the Royal Astronomical Society. It’s some interesting food for thought as NASA ponders an asteroid retrieval mission that so far has met with skeptical Congress representatives.

Source: Royal Astronomical Society

July 4, 2013December 23, 2015 by Jason Major

A Galaxy Grows Fat on Nearby Gas

An artist’s impression showing a galaxy in the process of pulling in cool gas from its surroundings. (ESO/L. Calçada/ESA/AOES Medialab)

If you live in the U.S. you may be enjoying a sultry summer day off in honor of Independence Day, or at least have plans to get together with friends and family at some point to partake in some barbecued goodies and a favorite beverage (or three). And as you saunter around the picnic table scooping up platefuls of potato salad, cole slaw, and deviled eggs, you can also draw a correlation between your own steady accumulation of mayonnaise-marinated mass and a distant hungry galaxy located over 11 billion light-years away.

Astronomers have always suspected that galaxies grow by pulling in material from their surroundings, but this process has proved very difficult to observe directly. Now, ESO’s Very Large Telescope has been used to study a very rare alignment between a distant galaxy and an even more distant quasar — the extremely bright center of a galaxy powered by a supermassive black hole. The light from the quasar passes through the material around the foreground galaxy before reaching Earth, making it possible to explore in detail the properties of the in-falling gas and giving the best view so far of a galaxy in the act of feeding.

“This kind of alignment is very rare and it has allowed us to make unique observations,” said Nicolas Bouché of the Research Institute in Astrophysics and Planetology (IRAP) in Toulouse, France, lead author of the new paper. “We were able to use ESO’s Very Large Telescope to peer at both the galaxy itself and its surrounding gas. This meant we could attack an important problem in galaxy formation: how do galaxies grow and feed star formation?”

A beam from the Laser Star Guide on one of the VLT's four Unit Telescopes helps to correct the blurring effect of Earth's atmosphere before making observations (ESO/Y. Beletsky) — A beam from the Laser Star Guide on one of the VLT’s four Unit Telescopes helps to correct the blurring effect of Earth’s atmosphere before making observations (ESO/Y. Beletsky)

Galaxies quickly deplete their reservoirs of gas as they create new stars and so must somehow be continuously replenished with fresh gas to keep going. Astronomers suspected that the answer to this problem lay in the collection of cool gas from the surroundings by the gravitational pull of the galaxy. In this scenario, a galaxy drags gas inwards which then circles around it, rotating with it before falling in.

Although some evidence of such accretion had been observed in galaxies before, the motion of the gas and its other properties had not been fully explored up to now.

Astronomers have already found evidence of material around galaxies in the early Universe, but this is the first time that they have been able to show clearly that the material is moving inwards rather than outwards, and also to determine the composition of this fresh fuel for future generations of stars. And in this particular instance, without the quasar’s light to act as a probe the surrounding gas would be undetectable.

“In this case we were lucky that the quasar happened to be in just the right place for its light to pass through the infalling gas. The next generation of extremely large telescopes will enable studies with multiple sightlines per galaxy and provide a much more complete view,” concluded co-author Crystal Martin of the University of California Santa Barbara.

This research was presented in a paper entitled “Signatures of Cool Gas Fueling a Star-Forming Galaxy at Redshift 2.3”, to appear in the July 5, 2013 issue of the journal Science.

Source: ESO news release

July 4, 2013March 16, 2017 by Fraser Cain

How Many Moons Does Earth Have?

Look up into the night sky and count the moons. You can see only one moon, “the” Moon. But does the Earth have any other moons? Around the Solar System, multiple moons are the rule. Jupiter has 67 natural satellites, even Mars has two asteroid-like moons.

Could Earth have more than one?

Officially, the answer is no. The Earth has a single moon.

Today.

It’s possible Earth had more than one moon in the past, millions or even billions of years ago. Strange terrain on the far side of the Moon could be explained by a second moon crashing into it, depositing a layer of material tens of kilometers deep.

Moons could come and go over the billions of years of the Earth’s history.

For example, Mars has two Moons, but not for long. Phobos, the larger moon, is spiraling inward and expected to crash into the planet within the next 10 million years. And so, in the future, Mars will only have a single Moon, Deimos.

It’s also possible that the Earth might capture a Moon in the future. Neptune’s largest moon, Triton, orbits in the opposite direction from the rest of the moons around the planet. This suggests that Triton was actually a captured Kuiper Belt Object which strayed too close to the planet.

In fact, we did capture a 5-metre asteroid called 2006 RH120. It orbited the Earth four times during 2006/2007 before getting ejected again.

So we can assume events like this have happened in the past.

Additionally, we might have more moons, but they haven’t been discovered yet because they’re just too small. Researchers have calculated that there could be meter-sized asteroids in orbit around the Earth, remaining in orbit for hundreds of years before gravitational interactions push them out again.

And there are other objects that interact with Earth’s orbit in strange ways. Scientists don’t consider them moons, but they do stick around in our neighbourhood:

Asteroid 3753 Cruithne is in an orbital resonance with the Earth. It has a highly eccentric orbit, but takes exactly one year to orbit the Sun. From our perspective, it follows a slow, horse-shoe shaped path across the sky. Since the discovery of Cruithne in 1986, several other resonant near-Earth objects have been discovered.

There’s 2010 TK7, the Earth’s only known Trojan asteroid. It leads the Earth in the exact same orbit around the Sun, in a gravitationally stable point in space.

So, the answer… Earth only has a single Moon. Today. We might have had more moons in the past, and we might capture more in the future, but for right now… enjoy the one we’ve got.

Want to learn more? Here are some articles on Universe Today we’ve written about this topic:
What are some objects known as Earth’s other moons?
Did Earth have more than one moon in the past?
Does Earth have many tiny moons?

You might also enjoy this episode of Astronomy Cast: Where did the Moon come from?

July 4, 2013December 23, 2015 by Ken Kremer

NASA’s Independence Day Fireworks from Wallops Investigates Earth’s Global Daytime Dynamo Current

July 4 Morning Fireworks from NASA!
A NASA Black Brant V Sounding Rocket launches in support of the Daytime Dynamo Mission on July 4, 2013 from NASA Wallops Flight Facility, VA. Credit: NASA/J. Eggers[/caption]

WALLOPS ISLAND, VA – Today, July 4, NASA celebrated America’s Independence Day with a spectacular fireworks display of a dynamic duo of sounding rockets – blasting off barely 15 seconds apart this morning from the agencies NASA Wallops Island facility on the Eastern Shore of Virginia on a science experiment to study the ionosphere.

The goal of the two rocket salvo was an in depth investigation of the electrical currents in Earth’s ionosphere – called the Daytime Dynamo.

The Dynamo electrical current sweeps through the ionosphere, a layer of charged particles that extends from about 30 to 600 miles above Earth.

Disruptions in the ionosphere can scramble radio wave signals for critical communications and navigations transmissions that can impact our every day lives.

The launches suffered multiple delays over the past 2 weeks due to weather, winds, errant boats and unacceptable science conditions in the upper atmosphere.

A Black Brant V launches first in support of Daytime Dynamo. Terroer improved Orion (at right) followed 15 seconds later from NASA Wallops on July 4, 2013. Credit: NASA/P. Black

At last, the Fourth of July was the irresistible charm.

The liftoff times were 10:31:25 a.m. for the Black Brant V and 10:31:40 a.m. (EDT) for the Terrier-Improved Orion.

The experiment involved launching two suborbital rockets and also dispatching a NASA King Air airplane to collect a stream of airborne science measurements.

Daytime Dynamo is a joint project between NASA and the Japanese Space Agency, or Japan Aerospace Exploration Agency, or JAXA, said Robert Pfaff to Universe Today in an exclusive interview inside Mission Control at Wallops. Pfaff is the principle investigator for the Dynamo sounding rocket at NASA’s Goddard Space Flight Center in Greenbelt, Md.

“The dynamo changes during the day and varies with the season,” Pfaff told me.

But they only have one chance to launch. So the science team has to pick the best time to meet the science objectives.

“We would launch every month if we could and had the funding, in order to even more fully characterize the Dynamo.”

Two rocket salvo comprising a Black Brant V (left) and a Terrier-Improved Orion (right) sit ready to launch as part of the Daytime Dynamo mission in this panoramic view from NASA Wallops Flight Facility at Virginia’s Eastern Shore. Credit: Ken Kremer/kenkremer.com

The 35 foot tall single-stage Black Brant V launched first. It carried a 600 pound payload to collect the baseline data to characterize the neutral and charged ionospheric particles as it blasted skyward.

The 33 foot tall two-stage Terrier-Improved Orion took off just 15 seconds later in the wake of the exhaust of the Black Brant V.

Exhaust trails from Black Brant V and a Terrier-Improved Orion launched in support of Daytime Dynamo mission on July 4, 2013. Credit: NASA P. Black — Exhaust trails from Black Brant V and a Terrier-Improved Orion launched in support of Daytime Dynamo mission on July 4, 2013. Credit: NASA/P. Black

The Terrier-Improved Orion successfully deployed a lengthy trail of lithium gas from a pressurized canister that created a chemical tracer to track how the upper atmospheric winds vary with altitude. These winds are believed to be the drivers of the dynamo currents.

Both rockets fly for about five minutes to an altitude of some 100 miles up in the ionosphere. They both splashed down in the ocean after about 15 minutes.

NASA’s King Air aircraft was essential to the mission. I toured the airplane on the Wallops runway for an up-close look inside. It is outfitted with a bank of precisely aimed analytical instruments peering through the aircraft windows to capture the critical science data – see my photos herein.

“The King Air launches about an hour before the scheduled liftoff time,” Pfaff told me.

“It uses special cameras and filters to collect visible and infrared spectroscopic data from the lithium tracer to characterize the daytime dynamo.”

The science instruments are newly developed technology to make the daytime measurements of the lithium tracer and were jointly created by NASA, JAXA and scientists at Clemson University.

“Everything worked as planned,” Pfaff announced from Wallops Mission Control soon after the magnificent Fourth of July fireworks show this morning.

Ken Kremer

Black Brant V (left) and a Terrier-Improved Orion (right) rockets sit on launch pads as part of the Daytime Dynamo mission in this up close view from NASA Wallops Flight Facility at Virginia’s Eastern Shore. Credit: Ken Kremer/kenkremer.com — Black Brant V (left) and Terrier-Improved Orion (right) rockets sit on launch pads as part of the Daytime Dynamo mission in this up close view from NASA Wallops Flight Facility at Virginia’s Eastern Shore. Credit: Ken Kremer/kenkremer.com

Inside cabin view of NASA King Air aircraft outfitted with science instrument mounts to support a of cameras to capture visible and infrared spectroscopic measurements in support of Daytime Dynamic launches on July 4, 2013. Credit: Ken Kremer/kenkremer.com — Inside cabin view of NASA King Air aircraft outfitted with science instrument mounts to support a bank of cameras to capture visible and infrared spectroscopic measurements in support of Daytime Dynamic launches on July 4, 2013. Credit: Ken Kremer/kenkremer.com

Robert Pfaff (right), Science Principle Investigator and Ken Kremer of Universe Today (left) discuss NASA’s Daytime Dynamo mission inside NASA Wallop’s Mission Control. Credit: Ken Kremer/kenkremer.com

July 4, 2013December 23, 2015 by Elizabeth Howell

When We Look For Life Beyond Earth, Let’s Consider Dying Planets: Study

Upper Geyser Basin region in Yellowstone National Park in Wyoming. A new study supposes the Earth will look like this after the sun heats up in a few billion years' time. Credit: Jack O’Malley-James

Bacteria. They’re so resilient that they can survive just about anywhere on Earth, even in spots of extreme hot or cold. As the sun warms up in the next few billion years, it’s likely that bacteria will be the only living creatures left on the planet, according to new research.

The study not only has implications for human survival — hopefully, our descendants will have left by then — but also our search for life on other planets. By predicting the signature these bacteria leave behind on the atmosphere, we can better hone our search for new planets, the study states.

Earth’s history shows that a species, just like an individual, can expect a lifetime that only lasts for so long. Sometimes a catastrophic event will wipe out a species, like what likely happened to the dinosaurs around 65 million years ago when a huge asteroid hit the Earth. Other times, it’s a slow process that is infinitesimal in an individual’s lifetime, but will eventually lead to changes that are unfriendly for life.

Thermophilic (heat-loving) bacteria may be among the last living creatures on Earth, the study suggests. Credit: Mark Amend / NOAA Photo Library

A computer model by Ph.D. astrobiologist Jack O’Malley James, who is at the University of St Andrews, suggests the first changes will take place in only a billion years. He will present his research at the ongoing Royal Astronomical Society national meeting at St. Andrews, Scotland, which is taking place this week.

“Increased evaporation rates and chemical reactions with rainwater will draw more and more carbon dioxide from the Earth’s atmosphere,” the Royal Astronomical Society stated. “The falling levels of CO2 [carbon dioxide] will lead to the disappearance of plants and animals and our home planet will become a world of microbes.”

Earth will then run out of oxygen and begin to dry out as temperatures rise and the oceans evaporate. Around two billion years in the future, there will be no oceans left.

The Sun in H-Alpha with close-up on a rushing prominence on 02-07-2013. Credit and copyright: John Chumack. — The sun, which allows Earth to be life-friendly right now, will warm up the planet and kill off most live forms in the next few billion years. Credit and copyright: John Chumack.

“The far-future Earth will be very hostile to life by this point,” O’Malley James stated. “All living things require liquid water, so any remaining life will be restricted to pockets of liquid water, perhaps at cooler, higher altitudes or in caves or underground.”

Life would disappear almost altogether in about 2.8 billion years.

Thankfully, humans plenty of time to figure out how to get around this problem. In the meantime, we can use the knowledge when seeking life beyond Earth.

Searches these days often focus on finding life like our own, which would leave “fingerprints” behind like oxygen and ozone.

“Life in the Earth’s far future will be very different to this, which means, to detect life like this on other planets we need to search for a whole new set of clues,” O’Malley James stated. “By the point at which all life disappears from the planet [surface], we’re left with a nitrogen:carbon-dioxide atmosphere, with methane being the only sign of active life”.

More information on this research is contained in an April 2013 article in the International Journal of Astrobiology.

Source: Royal Astronomical Society

July 3, 2013December 23, 2015 by Bob King

What You Can See in the Sky While Waiting for Fireworks on The 4th Of July

A thin lunar crescent rises beneath the Pleiades star cluster tomorrow morning at dawn. This map shows the sky facing northeast about 4 a.m. local time. Maps created with Stellarium

The sky can be a showy stage with big-time events like eclipses, meteor showers and the occasional bright comet, but most nights have a quiet beauty that whispers instead of shouts. The contrast between hype and hush is no more apparent than on the 4th of July – American independence day celebration – when we gather at a park or hilltop to watch the fireworks boom and flash across the heavens.

But there are other interesting things — some quiet fireworks — you can see in the sky to see while you are waiting for the holiday fireworks.

You can watch a less flashy but equally satisfying July 4th event as soon as tomorrow morning about the time the first bird lifts its voice at dawn. Look northeast to find a thin crescent moon dangling below the Seven Sisters star cluster. Also called the Pleiades, the cluster is a highlight of the winter evening sky. Though it seems out of place now at the height of summer, the Sisters remind us that nothing stands still. With the solstice behind us, winter’s already buckling his boots.

As you relax before the fireworks begin, look for two bright stars and two bright planets in the west and southwest skies. You can fit about three fists held at arm's length between Saturn and Arcturus. — As you relax before the fireworks begin, look for two bright stars and two bright planets in the west and southwest skies. You can fit about three fists held at arm’s length between Saturn and Arcturus.

While you’re waiting for the show to begin tomorrow night, take a look around the twilight sky and see how many celestial luminaries you can spot. If you’ve got kids in tow, share the view with them, too.

The brightest natural object in the sky will be Venus, glimmering low above the western horizon. Much further up in the southwest, look for a tall, skinny triangle outlined by orangy Arcturus, highest of the three, along with Saturn and Spica.

*Facing east brings the three bright stars of the Summer Triangle in to view.*

Twist around to face east to find another triangle, this one named after the summer season. Halfway up is Vega, the 5th brightest star in the sky, shining white and bright as burning magnesium. Below it you’ll spot the other Summer Triangle members, Altair in Aquila the Eagle and Deneb in Cygnus the Swan better known as the Northern Cross.

These bright stars and two planets coalesced from gas and dust millions to billions of years ago. Much has happened beneath their gaze, from the first stirrings of humankind to the crackle and boom of fireworks on a starry evening.

July 3, 2013December 23, 2015 by Elizabeth Howell

Moon Dust Could ‘Engulf’ Lunar Rovers — Especially During Sunrise and Sunset

Apollo 17 Mission — An Apollo 17 astronaut digs in the lunar regolith to study the mechanical behavior of moon dust. Credit: NASA

That video above is perhaps the ultimate off-roading adventure: taking a rover out for a spin on the moon. Look past the cool factor for a minute, though, and observe the dust falling down around that astronaut.

The crew aboard Apollo 16 (as well as other Apollo missions) had a lot of problems with regolith. It got into everything. It was so abrasive that it wore away some equipment in days. It smelled funny and probably wasn’t all that good to breathe in, either. Many have said that when we return to the moon, dust must be dealt with for long-term survival.

Things could get worse at sunrise and sunset. One new study (not peer-reviewed yet) finds a “serious risk” that rovers “could be engulfed in dust.” That’s because lunar dust appears to have electrostatic properties that, somehow, is triggered by changes in sunlight. (NASA is already doing some serious investigation into this matter using its orbiting missions.)

What the researchers did, in conjunction with ONERA (The French Center of Aerospace Research) was conduct simulations for two types of lunar regions — the terminator (the day/night boundary) and an area experiencing full sunlight.

“Dust particles were introduced into the simulation over a period of time, when both the surface and the rover were in electrical equilibrium,” the Royal Astronomical Society stated.

“In both the test cases, dust particles travel upwards above the height of the rover, but results suggest that they move in different directions. On the day side, the particles are pushed outwards and on the terminator the dust travels upwards and inwards above the rover, regrouping in the vacuum above it. The terminator simulation began with a region void of dust which was later filled by lunar dust particles.”

The bottom line? A lunar rover could accumulate a significant amount of dust on the moon, especially if it’s sitting at or near the terminator. This could be addressed by using dome-shaped rovers that would see the dust fall off, added lead author Farideh Honary, a physicist at the University of Lancaster, in a statement.

The work was presented at the RAS National Astronomy Meeting today (July 3). A paper has been submitted to the Journal for Geophysical Research, so more details should be forthcoming if and when it is published.

Credit: Royal Astronomical Society

July 3, 2013December 23, 2015 by Elizabeth Howell

‘The New Cool’: How These Sharp Space Pictures Were Snapped From A Ground Telescope

A near-infrared view of NGC 4038 (one of the Antenna Galaxies) obtained with the Gemini Observatory's new adaptive optics system. Credit: Image data from Rodrigo Carrasco, GeMS System Verification Team, Gemini Observatory. Color composite image by Travis Rector, University of Alaska Anchorage.

Rise above Earth with a telescope, and one huge obstacle to astronomy is removed: the atmosphere. We love breathing that oxygen-nitrogen mix, but it’s sure not fun to peer through it. Ground-based telescopes have to deal with air turbulence and other side effects of the air we need to breathe.

Enter adaptive optics — laser-based systems that can track the distortions in the air and tell computers in powerful telescopes how to flex their mirrors. That sparkling picture above came due to a new system at the Gemini South telescope in Chile.

It’s one of only a handful pictures released, but astronomers are already rolling out the superlatives.

“GeMS sets the new cool in adaptive optics,” stated Tim Davidge, an astronomer at Canada’s Dominion Astrophysical Observatory.

The planetary nebula NGC 2346. Credit: Gemini Observatory/AURA (Image data from Letizia Stanghellini, National Optical Astronomy Observatory, Tucson, Arizona. Color composite image by Travis Rector, University of Alaska Anchorage.)

“It opens up all sorts of exciting science possibilities for Gemini, while also demonstrating technology that is essential for the next generation of ground-based mega-telescopes. With GeMS we are entering a radically new, and awesome, era for ground-based optical astronomy.”

Other telescopes have adaptive optics, but the Gemini Multi-Conjugate Adaptive Optics System (GEMS) has some changes to what’s already used.

It uses a technique called “multi-conjugate adaptive optics”. This increases the possible size of sky swaths the telescope can image, while also giving a sharp view across the entire field. According to the observatory, the new system makes Gemini’s eight-meter mirror 10 to 20 times more efficient.

The Gemini South telescope during laser operations with GeMS/GSAOI. Credit: Manuel Paredes

The system uses a constellation of five laser guide stars, and has several mirrors that can deform according to measurements obtained by the sodium laser. We have more technical details in this past Universe Today story by Tammy Plotner.

The next step will be seeing what kind of science Gemini can produce from the ground with this laser system. Some possible directions include supernova research, star populations in galaxies outside of the Milky Way, and studying more detail in planetary nebulae — the remnants of low- and medium-mass star.

Check out more photos from Gemini at this link.

Source: Gemini Observatory