Posted on by Elizabeth Howell

Wow! Water Ice Clouds Suspected In Brown Dwarf Beyond The Solar System

Artist's conception of brown dwarf WISE J085510.83-071442.5, which may host water ice clouds in its atmosphere. Credit: Rob Gizis (CUNY BMCC / YouTube (screenshot)

What are planetary atmospheres made of? Figuring out the answer to that question is a big step on the road to learning about habitability, assuming that life tends to flourish in atmospheres like our own.

While there is a debate about how indicative the presence of, say, oxygen or water is of life on Earth-like planets, astronomers do agree more study is required to learn about the atmospheres of planets beyond our solar system.

Which is why this latest find is so exciting — one astronomy team says it may have spotted water ice clouds in a brown dwarf (an object between the size of a planet and a star) that is relatively close to our solar system. The find is tentative and also in an object that likely does not host life, but it’s hoped that telescopes may get better at examining atmospheres in the future.

The object is called WISE J085510.83-071442.5, or W0855 for short. It’s the coldest brown dwarf ever detected, with an average temperature between 225 degrees Kelvin (-55 Fahrenheit, or -48 Celsius) and 265 Kelvin (17 Fahrenheit, or -8 Celsius.) It’s believed to be about three to 10 times the mass of Jupiter.

Astronomers looked at W0855 with an infrared mosaic imager on the 6.5-meter Magellan Baade telescope, which is located at Las Campanas Observatory in Chile. The team obtained 151 images across three nights in May 2014.

Astronomers plotted the brown dwarf on a color-magnitude chart, which is a variant of famous Hertzsprung-Russell diagram used to learn more about stars by comparing their absolute magnitude against their spectral types. “Color-Magnitude diagrams are a tool for investigating atmospheric properties of the brown dwarf population as well as testing model predictions,” the authors wrote in their paper.

Based on previous work on brown dwarf atmospheres, the team plotted W0855 and modelled it, discovering it fell into a range that made water ice clouds possible. It should be noted here that water ice is known to exist in all four gas giants of our own Solar System: Jupiter, Saturn, Uranus, and Neptune.

“Non-equilibrium chemistry or non-solar metallicity may change predictions,” the authors cautioned in their paper. “However, using currently available model approaches, this is the first candidate outside our own solar system to have direct evidence for water clouds.”

The research, led by the Carnegie Institution for Science’s Jacqueline Faherty, was published in Astrophysical Journal Letters. A preprint version of the paper is available on Arxiv.

Source: Carnegie Institution for Science

Posted on by Elizabeth Howell

Lunar Love: Stunning Shots Abound In Phases Around The SuperMoon

The gibbous moon shines on Sept. 5, 2014. Credit: Christian Kamber

While the SuperMoon of earlier this week got a lot of attention — and rightly so, given the Moon was closest in its orbit to Earth when it was full — the waning and waxing phases around our celestial neighbor are also beautiful. Haunting, in fact.

These shots were taken by members of our Universe Today Flickr pool, with the moon either entering or exiting the full moon phase. Got some stunning astronomy shots to share? Feel free to add your contributions to the group (which says you will give us permission to publish) and we may include them in a future story.

The moon in its waning gibbous phase on Sept. 12, 2014. Photo taken with a Canon 700D attached to a Maksutov 127mm telescope. Credit: Sarah&Simon Fisher
The moon in its waning gibbous phase on Sept. 12, 2014. Photo taken with a Canon 700D attached to a Maksutov 127mm telescope. Credit: Sarah&Simon Fisher
The moon shines red in this photo taken from Newcastle upon Tyne, England on Sept. 11, 2014. Credit: David Blanchflower
The moon shines red in this photo taken from Newcastle upon Tyne, England on Sept. 11, 2014. Credit: David Blanchflower
The large craters Atlas (left) and Hercules (below) on the moon. Taken using a Canon 1100D. Credit: Paul M. Hutchinson
The large craters Atlas (left) and Hercules (below) on the moon. Taken using a Canon 1100D. Credit: Paul M. Hutchinson

EDIT: We just received a nice sequence of shots from Laura Austin:

Posted on by Elizabeth Howell

‘Venus Zone’: The Anti-Habitable Area Around A Star That Can Breed Hell

A radar view of Venus taken by the Magellan spacecraft, with some gaps filled in by the Pioneer Venus orbiter. Credit: NASA/JPL

Our hothouse planet of the solar system, Venus, is possibly a product of how close it is to the Sun, new research reveals. The team who have come up with a definition of a “Venus zone” around stars, saying that knowing where this area is could help pin down other areas that are more habitable for potential life.

“We believe the Earth and Venus had similar starts in terms of their atmospheric evolution,” stated lead author Stephen Kane, an astronomer at San Francisco State University. “Something changed at one point, and the obvious difference between the two is proximity to the Sun.”

The habitable region around a star is poorly understood because scientists don’t quite know what conditions are necessary for life. It usually refers to the area where liquid water is possible, although this also depends on the climate of the planet itself. Clouds, terrain and atmospheric composition are just some of the variables that could affect habitability.

Artist’s impression of a massive asteroid belt in orbit around a star. Credit: NASA-JPL / Caltech / T. Pyle (SSC)
Artist’s impression of a massive asteroid belt in orbit around a star. Credit: NASA-JPL / Caltech / T. Pyle (SSC)

To better figure out where potential Venus-like exoplanets lurk, Kane’s team used data from the planet-hunting Kepler Space Telescope and examined solar flux — or how much solar energy a planet gets — to figure out where the Venus zone would be. The zone is then defined between two regions: where a planet could have the “runaway greenhouse effect” seen on Venus, and the spot where the planet is so close to its star that energy would wear away its atmosphere.

The first step would be pinpointing which planets reside within these zones. In future decades, astronomers could then examine the planetary atmospheres with telescopes to learn more about how they are composed — and how similar they are to Earth or Venus. Meanwhile, Kane’s team plans to model if carbon in the planet’s atmosphere could affect the boundaries of the zone.

“If we find all of these planets in the Venus Zone have a runaway greenhouse-gas effect, then we know that the distance a planet is from its star is a major determining factor,” Kane stated. “That’s helpful to understanding the history between Venus and Earth.”

A preprint version of the paper is available on the Arxiv website. The research has been accepted for publication in Astrophysical Journal Letters.

Source: San Francisco State University

Posted on by Elizabeth Howell

Aurora Watch! Two Solar Particle Blasts Could Start Smacking Into Earth Friday

A solar blast erupts in this picture captured by the Solar and Heliospheric Observatory on Sept. 10, 2014. Credit: ESA / NASA / SOHO

Bim, bam, smash! The Sun hurled two clouds of particles in our general direction, putting space weather watchers on alert. There’s now a high chance of auroras on Sept. 12 (Friday), according to the National Oceanic and Atmospheric Administration, with more activity possible during the weekend.

The coronal mass ejections erupted Sept. 9 and Sept. 10 from sunspot AR2158. The Sept. 10 flare packed the strongest class punch the sun has, an X-flare, which briefly caused HF radio blackouts on Earth. We have some amateur shots of the sunspot and Sun below.

“Radio emissions from shock waves at the leading edge of the CME suggest that the cloud tore through the sun’s atmosphere at speeds as high as 3,750 km/s [2,330 miles per second],” wrote SpaceWeather.com. “That would make this a very fast moving storm, and likely to reach Earth before the weekend. Auroras are definitely in the offing.”

Photographer John Chumack captured the Sun and AR2158 in these pictures from Monday (Sept. 8). If you’ve got some great Sun shots to share, be sure to put it on our Universe Today Flickr group!

Sunspot AR2158 taken on Sept. 8, 2014. Credit: John Chumack
Sunspot AR2158 taken on Sept. 8, 2014. Credit: John Chumack
The Sun on Sept. 8, 2014, including active sunspots. Credit: John Chumack
The Sun on Sept. 8, 2014, including active sunspots. Credit: John Chumack
Posted on by Elizabeth Howell

Astronaut Snaps Amazing Picture Of His Crewmates Returning To Earth

The Expedition 40 crew returns to Earth, as seen from the International Space Station Sept. 10, 2014. Credit: Reid Wiseman / Twitter

Wow! See that bright streak in the photo above? That’s a shot of the Expedition 40 crew making a flawless return from the International Space Station yesterday (Sept. 10) … a shot taken from space itself.

“Our view of the picture perfect reentry of TMA-12M,” wrote Expedition 41 astronaut Reid Wiseman, who just hours before bid farewell to Steve Swanson (NASA), Alexander Skvortsov (Roscosmos) and Oleg Artemyev (Roscosmos). The re-entry was in fact so perfect that TV cameras caught the parachute immediately after deployment, which doesn’t always happen.

As you can see in the video replay below, the Soyuz made a bulls-eye landing near Dzhezkazgan, Kazakhstan at 10:23 p.m. EDT (2:23 a.m. UTC). There are now only three people tending to the space station until the rest of the Expedition 41 crew launches, which is expected to happen Sept. 25.

Posted on by Elizabeth Howell

Elemental Mystery: Lithium Is Also Rare Outside Of The Milky Way

An image of globular cluster M54 taken by the Very Large Telescope Survey Telescope at the European Southern Observatory's Paranal Observatory in northern Chile. Credit: ESO

This new picture of M54 — a part of a satellite galaxy to the Milky Way called the Sagittarius Dwarf Galaxy — is part of a “test case” astronomers have to figure out a mystery of missing lithium.

For decades, astronomers have been aware of a dearth of lithium in our own galaxy, the Milky Way. This image from the Very Large Telescope’s Survey Telescope represents the first effort to probe for the element outside of our galaxy.

“Most of the light chemical element lithium now present in the Universe was produced during the Big Bang, along with hydrogen and helium, but in much smaller quantities,” the European Southern Observatory stated.

“Astronomers can calculate quite accurately how much lithium they expect to find in the early Universe, and from this work out how much they should see in old stars. But the numbers don’t match — there is about three times less lithium in stars than expected. This mystery remains, despite several decades of work.”

In any case, observations of M54 show that the amount of lithium there is similar to the Milky Way — meaning that the lithium problem is not confined to our own galaxy. A paper based on the research was published in the Monthly Notices of the Royal Astronomical Society. The research was led by Alessio Mucciarelli at the University of Bologna in Italy.

Source: European Southern Observatory

Posted on by Elizabeth Howell

Mars Panorama Shows Off Rocks, Mountains and Curiosity Rover

A portion of a panorama based on pictures taken by the Mars Curiosity rover on Sol 739 in September 2014. Credit: Andrew Bodrov/NASA/JPL-Caltech

Hey, it’s Mars in your browser! Panning around this scene that the Mars Curiosity rover captured earlier this month is the next best thing to being on the Red Planet.

Close by the rover’s is the terrain that proved far more challenging for mission planners than anticipated, and further in the distance you can see mountains — including the ultimate destination for this mission, Mount Sharp (Aeolis Mons).

The panorama, done by Andrew Bodrov, is based on pictures that Curiosity took during Sol 739 of its mission on Mars, which began in August 2012.

The Curiosity mission recently drew the concern of a NASA Senior Review panel, which said that the mission may be moving too fast to Mount Sharp and sacrificing looking carefully at other sites that could preserve signs of habitability.

The rover recently passed over a drilling target due to the nature of the rocks it was looking at, which were loose, unstable and at risk to the rover if they moved in an unpredictable way.

Posted on by Elizabeth Howell

How Dark Matter Could Reduce The Fleet Of Galaxies Following The Milky Way

On either side of the white line in the picture are two models of how dark matter is distributed in a galaxy similar to the Milky Way. At left, non-interacting cold dark matter creates satellite galaxies. At right, dark matter interacting with other particles makes the number of observed satellite galaxies smaller. Credit: Durham University

Funny how small particle interactions can have such a big effect on the neighbors of the Milky Way. For a while, scientists have been puzzled about the dearth of small satellite galaxies surrounding our home galaxy.

They thought that cold dark matter in our galaxy should encourage small galaxies to form, which created a puzzle. Now, a new set of research suggests the dark matter actually interacted with small bits of normal matter (photons and neutrinos) and the dark matter scattered away, reducing the amount of material available for building galaxies.

“We don’t know how strong these interactions should be, so this is where our simulations come in,” stated Celine Boehm, a particle physicist at Durham University who led the research. “By tuning the strength of the scattering of particles, we change the number of small galaxies, which lets us learn more about the physics of dark matter and how it might interact with other particles in the Universe.”

Artist's conception of the Milky Way galaxy based on the latest survey data from ESO’s VISTA telescope at the Paranal Observatory. A prominent bar of older, yellower stars lies at galaxy center surrounded by a series of spiral arms. The galaxy spans some 100,000 light years. Credit: NASA/JPL-Caltech, ESO, J. Hurt
Artist’s conception of the Milky Way galaxy based on the latest survey data from ESO’s VISTA telescope at the Paranal Observatory. A prominent bar of older, yellower stars lies at galaxy center surrounded by a series of spiral arms. The galaxy spans some 100,000 light years. Credit: NASA/JPL-Caltech, ESO, J. Hurt

Dark matter is a poorly understood part of the Universe, which is frustrating for scientists because it (along with dark energy) is believed to make up the majority of our Cosmos. There are several postulated types of it, but the main thing to understand is dark matter is hard to detect (except, in certain cases, through its interactions with gravity.)

This isn’t the only explanation for why the galaxies are missing, the scientists caution. Perhaps the universe’s first stars were so hot that they affected the gas that other stars formed from, for example.

A paper on the research was published in the Monthly Notices of the Royal Astronomical Society and is also available in preprint version on Arxiv.

Source: Royal Astronomical Society

Posted on by Elizabeth Howell

Could Plate Tectonics Create Cracks And Odd Terrain In Cold Europa’s Crust?

Reprocessed Galileo image of Europa's frozen surface by Ted Stryk (NASA/JPL/Ted Stryk)
Reprocessed Galileo image of Europa's frozen surface by Ted Stryk (NASA/JPL/Ted Stryk)

Mysteries abound on icy Europa, that cold moon of Jupiter. Even years after the Galileo spacecraft finished its mission in the Jovian system, scientists are still trying to figure out the nature of the cracks on Europa’s surface. In an exciting find, one new paper suggests that at least part of the terrain could be due to plate tectonics.

If proven, this would be the first time that plate tectonics have been strongly suggested as a process working beyond Earth. On our home planet, scientists believe that this process, which happens as plates of Earth’s crust move, is responsible for creating mountains and volcanoes and earthquakes.

So why do they think this process is happening on Europa? The short answer is, weird terrain. For example, Scientists have seen evidence of what is called extension, which happens when the surface expands and then stuff from the layers below fills in the gap. But there were pieces of that understanding missing until now, the team says.

“We have been puzzled for years as to how all this new terrain could be formed, but we couldn’t figure out how it was accommodated,” stated Louise Prockter, a planetary scientist at Johns Hopkins University Applied Physics Laboratory who co-authored the study. “We finally think we’ve found the answer.”

An illustration of how subducting tectonic plates might work on Jupiter's moon, Europa. This would bring the moon's estimated 10-20 mile (20-30 kilometer) ice shell into the warmer insides of the moon. Credit: Noah Kroese, I.NK
An illustration of how subducting tectonic plates might work on Jupiter’s moon, Europa. This would bring the moon’s estimated 10-20 mile (20-30 kilometer) ice shell into the warmer insides of the moon. Credit: Noah Kroese, I.NK

Despite being pretty confident about the extension, scientists were unable to account for how all the new material arrived.

What the team did was try to model how Europa’s surface looked before how all the cracks appeared, and discovered that 7,700 square miles (20,000 square kilometers) couldn’t be accounted for in the high northern latitudes.

Looking more closely, they found ice volcanoes that they believe was on a surface plate, and missing mountains in what is thought to be a subduction zone. This suggests that stuff from the surface gets pushed underneath — not crushed into each other.

Rendering showing the location and size of water vapor plumes coming from Europa's south pole. Credit: NASA/ESA/L. Roth/SWRI/University of Cologne
Rendering showing the location and size of water vapor plumes coming from Europa’s south pole. Credit: NASA/ESA/L. Roth/SWRI/University of Cologne

“Europa may be more Earth-like than we imagined, if it has a global plate tectonic system,” stated Simon Kattenhorn of the University of Idaho, Moscow, who led the study.

“Not only does this discovery make it one of the most geologically interesting bodies in the solar system, it also implies two-way communication between the exterior and interior — a way to move material from the surface into the ocean — a process which has significant implications for Europa’s potential as a habitable world.”

This adds more fuel to the desire of scientists to head out to Europa. NASA has requests out for ideas for a mission to the icy moon, and in late 2013 scientists reported icy plumes erupting from the moon (spotted in Hubble Space Telescope observations).

A paper on the new research was recently published in Nature Geoscience.

Source: NASA

Posted on by Elizabeth Howell

China’s Yutu Rover Is Still Alive, Reports Say, As Lunar Panorama Released

A still from CCTV showing part of a panorama from the Yutu rover. Credit: CCTV/YouTube

It hasn’t been an easy few lunar months for the Yutu rover, which reportedly had problems positioning its solar panels in March while exploring the lunar surface. That said, reports are emerging that the rover is still alive. Along with those reports came a new panorama released in time for the Moon Festival in that country.

As you can see in the video above, the new panorama shows the Chang’e-3 lander and the tracks of the Yutu rover in the Mare Imbrium (Sea of Rains). The duo landed on the Moon on Dec. 14, 2013, with the rover on the top. Yutu then drove on its six wheels on to the surface only about seven hours after the touchdown happened.

The act was hailed as an accomplishment for China, which is the third nation to make a soft landing on the moon after the Soviet Union and the United States. It also was the first to touch down on the moon in more than a generation, as other lunar programs have focused on orbiters (such as NASA’s Lunar Reconnaissance Orbiter, which remains in operation above.)

According to the Twitter account UHF Satcom, the X-band carrier signal for Yutu was strongly audible from Earth yesterday (Sept. 7), although the lander was not audible.