A colony of microscopic fungi has survived for 18 months in Mars-like conditions on the International Space Station in a study that could affect future exploration of the red planet.
Native to the cold Antarctic, the fungi usually thrives when sheltered inside rocks, making it an ideal test subject for a simulation of the cold, dry desert conditions of Mars.
The fungi samples were housed in the EXPOSE-E unit which is situated on the outside of the ISS.
The isolated lab was built by the European Space Agency (ESA) to measure the affect of the harsh environment of open space on biological samples.
Along with microgravity, the fungi samples were exposed to low air pressure, extreme cold and intense UV radiation, to simulate the conditions that could be encountered on the way to Mars and on the planet itself.
Published in the journal Astrobiology, the study showed that more than 60 percent of the Cryomyces antarcticus and Cryomyces minteri microbes managed to survive their 18-month stay in less-than-cosy conditions on the ISS.
While this could hint at the possibility that if there was once life on Mars, it could still be there today, it may also hinder further exploration efforts.
While the ability to cultivate species originating from Earth on Mars could be good news for any future colonies, it could also mean that pioneers to the red planet could inadvertently contaminate it and potentially damage any existing ecosystem.
Via: Popular Mechanics
http://observer.com/
Advanced Extraterrestrial Life Could Be Flourishing at the Edges of Our Galaxy
Globular Cluster M10 as viewed by
The Hubble Telescope (NASA)
“A globular cluster might be the first place in which intelligent life is identified in our galaxy,” said Di Stefano, lead author of the study published from a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory.
These ancient globular star clusters are spherical in shape and can contain anywhere from hundreds of thousands to millions of stars. In fact, the oldest stars in the Milky Way can be found in these areas with a ripe age of about 10 billion years old and scientists believe some may have been around since the birth of our galaxy. The age of these clusters have previously played an essential role in helping astronomers pinpoint the center of the Milky Way and aid in determining the age of the universe.
What determines the possibility of life in a star system? Its “goldilocks” or habitable zone. This refers to a “just right” distance between the star and a nearby planet—which directly affects the average temperature and eventually the planet’s ability to produce liquid water. Brighter stars provide a larger potential habitable zone than their fainter counterparts but have a much shorter lifespan.
Habitable planets that could exist in these globular clusters would be huddled near dim red dwarfs and this is crucial because smaller orbits help protect those planets from the violent forces found in such a crowded galactic neighborhood—forces that could eventually push a smaller world into cold, interstellar space. Di Stefano claims that once these planets do form, “they can survive for long periods of time, even longer that the current age of the universe.”
Some of these clusters are packed to the brim and astronomers have estimated that some house up to a million stars that span a combined distance of up to 100 light-years. To give you an idea of how dense that is, our Sun’s nearest star is close to 4 light years away.
The main ideas drawn by this research include the high probability of the formation of potentially habitable worlds in a globular cluster due to the sheer volume of stars and that these worlds could survive for billions of years. This is important because complex life takes time to evolve and to develop the kind of intelligence needed to build and maintain a civilization—especially a space-faring one.
On Earth, cultures or nations that have had the ability to easily communicate and exchange ideas or resources with neighboring counterparts have evolved faster than those found in more remote areas. This same idea can apply to a planetary system. Our civilization as a whole is still in the early stages of exploring interstellar space—it was just three years ago that a man-made object, The Voyager spacecraft—breached the edge of our solar system.
According to this new research, a civilization that exists in a globular cluster would have a far more accelerated timeline in the progress of their exploration of neighboring systems. Their nearest star could be about 20 times closer to them than our nearest star is to us.
The difference is significant—a distance of 1 trillion miles in a cluster compared to 24 trillion miles in our neck of the woods. This could make interstellar travel and communication far easier for this possible civilization. “We call it the ‘globular cluster opportunity,’” says Di Stefano. “Sending a broadcast between the stars wouldn’t take any longer than a letter from the U.S. to Europe in the 18th century.”
Prior to this new research, scientists have always had doubts about whether intelligent life could exist in these areas due to the assumption that planets may not exist in these globular clusters at all. Given the old age, their stars would contain fewer of the elements that are essential in the creation of planets.
For example, the Iron and Silicon found on Earth were formed at a nuclear level over generations—through the death and birth of earlier stars. If the globular superclusters have some of the first stars in our galaxy, how could they have these essential elements that are only formed by their successors? It’s a valid question given the fact that astronomers have only discovered one planet so far among the 150 globular clusters found on the outskirts of our galaxy.
Dr. Di Stefano and her colleague Alak Ray of the Tata institute of Fundamental Research in Mumbai are challenging this hypothesis. They explain that Exoplanets—planets that exist outside of our solar system– have been found orbiting stars that have dramatically less metallic elements than our own Sun.
Di Stefano and Ray also claim that the existence of Earth-sized planets show no preference in relation to the amount of essential heavy or metallic elements in its star. This challenges the previous notion that the metal-deficient stars in the globular clusters would have no planets with potential life-harboring environments. “It’s premature to say there are no planets in globular clusters” expressed Ray.
Robin Seemangal focuses on NASA and advocacy for space exploration. He was born and raised in Brooklyn, where he currently resides. Find him on Instagram for more space-related content: @not_gatsby
http://www.universetoday.com/
An illustration of a large, rocky planet similar to the recently
discovered BD+20594b. Image: JPL-Caltech/NASA
Largest Rocky World Found
But thanks to the Kepler Spacecraft, and it’s ability to observe and collect data from other, distant, solar systems, we’ve found a rocky planet that’s bigger than we thought one could be. The planet, called BD+20594b, is half the diameter of Neptune, and composed entirely of rock.
BD+20594b is about 16 times as massive as Earth and half the diameter of Neptune. Its density is about 8 grams per cubic centimeter. It was first discovered in 2015 as it passed in between Kepler and its host star. Like a lot of discoveries, a little luck was involved. BD+20594b’s host star is exceptionally bright, which allowed more detailed observations than most exoplanets.
The discovery of BD+20594b is important for a couple of reasons: First, it shows us that there’s more going on in planetary formation than we thought. There’s more variety in planetary composition than we could’ve known from looking at our own Solar System. Second, comparing BD+20594b to other similar planets, like Kepler 10c—a previous candidate for largest rocky planet—gives astrophysicists an excellent laboratory for testing out our planet formation theories.
It also highlights the continuing importance of the Kepler mission, which started off just confirming the existence of exoplanets, and showing us how common they are. But with discoveries like this, Kepler is flexing its muscle, and starting to show us how our understanding of planetary formation is not as complete as we may have thought.
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