Friday, April 28, 2017

Voices on the Solar Wind Extended

Nick Wood writes -

(I am writing) just to let you know I have extended Lunar Voices on the Solar Wind (#266) to a book length 'Phulani on the Moon', now shortlisted for the Sanlam Youth Literature Prize in South Africa: 

Saturday, April 22, 2017

Catching a Few Rays

An image of a spacecraft, with two solar panels on either end, and a collection system in the open position, visible on the top of the spacecraft, with the lid open.
Reach overhead on a cloud-free, summer day, and you can almost believe like you can catch a few of its rays. While your efforts will prove to be unsuccessful, you should  know that scientists have literally caught some of the Sun's rays. And you know what's even cooler? There's a place on Earth where you can actually hold a piece of the Sun!

Stored within two tidy cleanrooms at the Johnson Space Center in Houston, Texas is a collection of metallic wafers and foils, and etched within their insides are particles of the solar wind

Friday, April 21, 2017

A Return to the Moon

45 years ago NASA last sent astronauts on a lunar mission. Now SpaceX CEO Elon Musk has announced his company's plans to send two private citizens on a flight around the moon in 2018 reminicent of NASA's Apollo 8-flight. The weeklong trip will look a lot like spacex-moon-flight — the first and only purely circumlunar, crewed mission in history

For the complete article, click here

Monday, April 17, 2017

Bringing Earth germs to Europa's salty seas? PLUS: Will we create mutant microorganisms during space travel?

As humanity extends its physical reach into the solar system, un­in­tended mixing of
Earth life with those of  other planets and or their moons becomes increasingly realistic.   What happens if/when we introduce Earth’s microbes to other planets? What if we bring alien micro-life back to Earth?  

Below and at the link, postdoc microbial researcher Jennifer Tsang considers the   practical & ethical questions regarding such interplanetary contamination .

Staying Safe in Space   

by Jennifer Tsang
The thought of bringing alien life forms to Earth or of creating dangerous mutant microorganisms during space travel might seem straight out of a science fiction movie. But are these concerns real­ly that far fetched? As our interest in astrobiology (the study of life in the universe) grows, the concern for an un­in­ten­tio­nal exchange of life between Earth and other celestial bodies becomes increasingly realistic. What happens if we introduce Earth’s microbes to other planets? What if we bring alien life back to Earth? Questions regarding such interplanetary contamination pose not on­ly practical issues but ethical ones as well.

Microbes cover every niche of our planet. The Dutch mi­cro­biologist Lourens Baas Becking once said, "everything is everywhere, but the environment selects." Microbes ex­ist as invisible passengers inhabiting all plants and ani­mals, including humans. Microbial life exists on Earth in habitats ranging from frigid waters to hydrothermal vents, from low to high pH, and even with or without oxygen. Clearly, microorganisms survive and even flourish in near­ly any condition imaginable. Because of this re­sil­i­ence, astrobiologists are concerned that microbial life could survive the stresses of space flight and possibly contaminate other planets upon arrival. We don’t want to travel to a new planet only to “discover” life that we mistakenly brought from Earth, nor do we want to disrupt life, or its evo­lution, on other planets.

Safeguarding against interplanetary contamination
As discussed at the American Association for the Advancement of Science (AAAS) meeting this Fe­bru­ary, NASA plans to send a spacecraft to Jupiter’s moon Europa in 2025 (Figure 1). The mission aims to search for undiscovered life on Europa. As water is necessary to sustain life, the large salt­water ocean beneath the icy surface of Europa makes it a hopeful candidate for extraterrestrial life (Figure 2). To minimize planetary contamination, the Europa lander will be built in a clean fa­ci­li­ty. Though a clean facility is “clean,” it is not sterile, and some species of bacteria have been found. Any microbes remaining on the lander will be baked out at temperatures greater than 125°C for hours to days. The lander will be encased in an aluminum biobarrier keeping con­ta­mi­nants at bay during its long journey to Europa. As Kevin Hand, an astrobiologist from NASA Jet Propulsion Laboratory, said during the AAAS meeting, “we want to keep Europa for Europans.”
Europa_poster(Click to enlarge) Figure 2. Cross-section of Europa. Source
Introducing microbial life to other planets is not the only risk. Microbes could be brought back to Earth knowingly for study or inadvertently through contaminated equip­ment. Samples must be handled with care to minimize any unknown risk to native life on Earth. The Europa lander mission is not scheduled to bring samples back to Earth, but sample-return is possible for future missions. Such missions may bring back anything from liquids, soil and rocks, or small amount of minerals that will be studied using instruments that could not be brought into space. To prevent contamination of Earth, collected samples are studied using the most stringent biocontainment facilities (BSL-4).
You may be wondering whether interplanetary contamination actually matters. After all, me­teo­rites and micrometeorites have bombarded planets in our solar system for four billion years. Ma­ny scientists believe the transfer of microbes between planets has already happened. Others think that we are unnecessarily cautious and should spend precious research dollars elsewhere. How­ev­er, can we risk a War of the Worlds-style alien invasion of Earth? The dilemma remains: we don’t know if interplanetary contamination is a real risk, but it seems reasonable to take precautions in case these risks exist.
Microbial evolution in space
Coming from a planet where microbes rule every niche (including the human body), it is inevitable that astronauts bring microbes from Earth onto space missions. What is unclear though is how mi­crobial life adapts and evolves to new conditions. Things get even more complicated when you throw in how the human microbiome and immune sys­tem changes in space. With these cir­cum­stan­ces, it is likely that host-microbe interactions will change upon leaving Earth.
There is strong evidence that the immune sys­tem is compromised during space travel. Moreover, the human microbiome becomes less diverse after time in space: samples from astronauts on the Salyut and Mir orbiting platforms showed a significant reduction in human microbiota diversity even after just two weeks! Opportunistic pathogens, which rely on reduced immune function or altered host microbiota to cause disease, have the potential to wreak havoc in space. Changes in our microbiome and immune sys­tem go hand in hand; our microbiome, just like our immune sys­tem, protects against pathogens.

Fig_3_Mark_and_Scott_Kelly_at_the_Johnson_Space_Center _Houston_TexasFigure 3. Scott and Mark Kelly. Source
To gain insight into changes in the human body during space flight, NASA began a study of twins. Identical ve­te­ran astronauts twins, Scott and Mark Kelly, provide an ideal comparison for the effects of long-term space mis­sions on the human body (Figure 3). Starting in March 2015 Scott spent a year on the International Space Sta­tion (ISS) while his brother Mark served as an earthbound control subject. By obtaining baseline measurements of each, scientists could pinpoint biological differences after a year of zero gravity and freeze-dried food. Fred Turek, a scientist from Northwestern University characterized the microorganisms from the twins and found differences in viral, bacterial, and fungal microbiome between them. In Scott’s microbiome, the ratio of Firmicutes and Bacteroidetes, two dominant bacterial groups in the gut, was altered upon space travel. Upon return to Earth, the ratio of the two bacterial species returned to pre-flight levels.

To make matters worse for astronauts, bacteria become more virulent and more resistant to an­ti­biotics in space. These changes are due to both increased radiation levels and the microgravity environment in space: environmental stressors that select for resistance. Radiation breaks DNA strands or damages DNA bases, preventing it from being read or replicated correctly, leading to mutations. After 40 days on Mir, mutation rates in yeast were two to three times higher than in ground controls. In a study of Bacillus subtilis spores, mutations leading to rifampicin resistance were induced by 2-4 orders of magnitude greater than Earth controls. A high mutation rate allows bacteria to more quickly adapt to changing conditions.
Under microgravity conditions, growth rate, motility, and metabolite production are also altered. This is likely due to reduced extracellular mass-transport, with movement of molecules limited in low gravity. A team of scientists from the University of Colorado, the Hudson Alpha Institute, and the University of Alabama, determined how microgravity affects gene expression of bacteria by comparing the same Ecoli strain grown on Earth and on the ISS. They found that cells grown on the ISS had increased expression of genes associated with starvation, metabolism, and use of al­ternative energy sources.
Many times, astronauts are unable to return to Earth until their space missions end. Because crewmembers may become sick or injured in space, it is essential that we understand the fate of microbial life in space. Between 1989 and 1998, there were 26 documented infections in space for US astronauts. Studies in the 1980s showed that antibiotics need to be 2-4 times more con­cen­tra­ted to kill Ecoli and Saureus in space than on the ground. Increased antibiotic resistance in bac­teria may mean that typical treatments are not effective, and increased virulence may mean that the symptoms of an infection are more severe. As we expand our reach into the solar system, we need to take precautions to make sure we do so safely for ourselves, the Earth, and other celestial bodies.
Jennifer Tsang is a postdoctoral research fellow studying antimicrobial resistance in the lab of James Kirby at Beth Israel Deaconess Medical Center. She blogs at The Microbial Menagerie.

Tuesday, April 04, 2017

NASA's Curiosity Mars Rover is Experiencing Wheel Deterioration

The NASA Curiosity Mars rover has developed a break on one of it's six battered aluminum wheels. A recent photo check of the rover's left middle wheel revealed two small breaks, NASA officials said Tuesday March 21. But the rover can still drive on the Martian surface with little difficulty.

The breaks were spotted in the wheel's raised treads, known as grousers, on Sunday March 19th after photos from Curiosity were compared to similar ones from a previous wheel check on Jan. 27. Pits, holes and dents have been noted before, but the two broken treads are the first sign of deeper wear on the affected wheel.

BMU 483 Is Now Online

In episode 483 - my first song is a toe tapper from the Kongos called Come With Me Now. In a break with the past, I play two back to back tracks.  My second is a cut from Bruno Mars called Can't Believe it Just Rang. 

My first story is by David Scholes called Return of the Benefactor.

in articles, researchers are trying to perfect food production using waste products.

The last story is a flash from the past. Thus it is another episode in Poul Anderson story Inside Earth.

Click HERE for podcast audio or down-load.