The Science Week in Review: March 29, 2015
This past week’s big science stories include the discovery of a new giant salamander-like beast from the Late Triassic period with a toilet-seat-shaped face, good news about the Ebola epidemic, and this weekend’s feature story about the launch of US Astronaut Scott Kelly on the beginning of his one year journey in space. I also highlight other great science news from around the web including a revised calculation of how long it would take you to fall through Earth, the discovery of “square ice,” and the “Angelina Jolie Effect.”
A Year in Space
How does a year in space affect the human body? NASA astronaut Scott Kelly and his twin brother Mark Kelly will help us answer this question that is undeniably critical for their mission to send humans to Mars in the next twenty years. Yesterday (March 27, 2015) Scott Kelly and Russian comrade Mikhail Kornienko were launched into orbit in a Russian Soyuz space capsule from Kazakhstan, with a six hour journey to the International Space Station (ISS). Once there, Kelly and Kornienko will remain in space for one year, during which they will provide new and essential medical data intended to reveal how a long period of time in space affects the human body. While scientists already know a lot about what happens to human physiology after about half a year in space, this current mission will reveal more about the challenges that NASA must confront in order to send humans on a long-term mission to Mars. Of course, the mission to Mars is currently a one-way ticket, but the journey there alone could easily take over a full year.
While you may know from the movies or media about muscle atrophy (loss) that occurs when in space due to the zero gravity atmosphere, there are a barrage of other complications that physicians must consider as well. One is loss of bone density, which also makes sense considering the zero gravity environment. Without the (literal) weight of the world pulling down on the astronauts, it takes considerably less effort to move about, and the body’s musculoskeletal system quickly weakens when it is not exerted. Abnormal blood and bodily fluid distribution is another issue when you remove Earth’s gravity from the equation. The kidneys, which are the body’s blood filtration system, may begin to work poorly, and blood may begin to become distributed in parts of the body that it normally doesn’t flow to as much, such as behind the eyes, resulting in an undesirable pressure. And while the potential psychological problems with confined space travel (i.e. on a long journey to Mars) have been duly noted by many, the compound effects of the central nervous system and what a zero-gravity environment may do to the physicochemical properties of the brain, and thus one’s psyche, have yet to be determined.
Aside from the year-long duration of the trip, this mission is particularly exciting for scientists because while Scott Kelly is being studied in space, his twin brother (and former NASA astronaut) Mark Kelly will be studied back here on good old planet Earth. This should allow for an excellent scientific comparison in regards to how Kelly’s physiology is altered in space compared to that of his brother. In addition to studies on bone and muscle strength, blood vessel structure, visual acuity, sensorimotor abilities and bodily fluid redistribution, this mission seeks to investigate the effects of space on Kelly’s microflora. Microbiologists have shown that the microorganisms inside our digestive systems play a bigger role in our health than was previously anticipated, and health scientists are continually acknowledging the importance of a lively microbial ecosystem for good human health (although what is considered abnormal versus healthy is still being worked out). Thus, monitoring changes in microbial biodiversity over time from the gastrointestinal tract of Astronaut Kelly (through the unceremonious analysis of fecal samples) will help provide data to keep future astronauts and Mars explorers healthy in space.
Suffice to say, there is a great deal of excitement amongst the astronomy community about the current “Year in Space” mission, and Time magazine will be covering the story from a scientific, social, and personal perspective through a series of documentaries about Scott Kelly and his close ones over the next year. The mission to spend a year in space is pretty exciting on its own, but it is the motivation to send humans to Mars that provides extra energy to the studies at hand. It will be interesting to see what the scientists and physicians learn from Scott and his brother in the year to come.
“Angelina Jolie Effect”
Last Tuesday Angelina Jolie Pitt wrote an opinion piece in the New York Times explaining her story and decision regarding the surgical removal of her ovaries. The choice was preceded by a double mastectomy back in 2013, a preventative measure after the discovery of a mutation in the BRCA1 gene and a strong family history of cancer. A news article from Nature describes a potential rebound in what genetic counsellors call the “Angelina Jolie Effect,” which describes the surge in genetic testing that was seen after Jolie’s decision to have the double mastectomy. Genetic testing is a complicated business, and Jolie does an excellent job of explaining her situation that led her to her decisions. Moral of the story though is that while genetic tests are useful, they alone do not always dictate the appropriate course of action in terms of medical care. Read her opinion piece for more.
Toilet-Seat Face Metoposaurus
Meet Metoposaurus algarvensis, a newly discovered species whose head has rightfully been called similar in size and shape to that of a toilet seat…(how’s that for name-calling?) Metoposaurus algarvensis belongs to the genus of Metoposaurids, giant salamander-like amphibians that were likely the top predator in fluvial (rivers and streams) and lacustrine (lake) environments in the Late Triassic around 220 and 230 million years ago. This was the period of time preceding the more familiar Jurassic and Cretaceous periods, famous for the beloved dinosaurs of course. Metoposaurids are common in upper Triassic sediments, but this was the first find of a species in the Iberian Peninsula, which includes Spain and Portugal.
Besides for its irresistible toilet-bowl shaped skull, this Metoposaurus find was notable for the good preservation of multiple specimens, and the fact that the two meter beast probably reached 100 kg in size. Not your friendly fire-bellied newt that you had for a pet as a kid (or maybe that was just me). The Metoposaurus genus is part of the Temnospondyli (doesn’t paleontology provide an infinite source of horrible spelling bee words?) order, which is worth mentioning since this group of ancient amphibians were world dominators throughout the Carboniferous, Permian, and Triassic periods. If you haven’t taken a geology class in a while, it will suffice to say that these time periods were ones filled with the primordial beasts that preceded the dinosaurs, and long preceded modern mammals. If you’re into bones, you can read all about Metoposaurus (23 pages of it) in the Journal of Vertebrate Paleontology. The rest of us can be grateful for the hard work the scientists do so that we can have cool pictures of the prehistoric past.
How long would it take you to fall through the Earth?
It’s an age-old question. What if we could hypothetically drill a hole through the center of the Earth, how long would it take to fall through to the other side? Assuming that we would not melt, be crushed, or undergo severe bruising from the ascent-followed descent, physicists and their students have estimated a travel time of 42 minutes. But these calculations have traditionally ignored the varying density of the Earth from the surface to the core. A new estimation that considers this factor, among others, places the journey at a shorter 38 minutes. You can read more about the details from an article on Science.
Ebola Epidemic Slows Down
Last Thursday Heinz Feldmann and colleagues from the National Institute of Allergy and Infectious Diseases provided a sigh of relief to those involved in Ebola virus relief work. In a study published in Science, they showed that the virus involved in the current outbreak is not mutating any faster than normal. Back in August, a team of scientists from Harvard published a paper indicating that the virus was evolving more quickly than expected, which would be bad news for those working on a vaccine. Ebola is an RNA virus, meaning that its genetic code is carried in a single strand of nucleotides. Humans, and even some viruses, use DNA as their primary genetic code, which is that two-stranded double helix that you’ve seen in cartoon-form as “Mr. DNA” in Jurassic Park. Most organisms have sophisticated repair machinery that serves to fix any mutations that occur in a single strand of your DNA. Because DNA is double-stranded, the repair machinery can look at one strand of the DNA to repair the mutation on the other strand. Viruses don’t do this, and RNA viruses like Ebola can thus mutate quickly, making it harder for the body to develop an immune response against a changing target, and likewise rendering potential new therapies against the virus void. Fortunately, thanks to the study by Feldmann et al., this does not appear to be the case, and the therapies in development and distribution for Ebola should still work to put a good fight up against the virus.
Most ice is hexagonal, sort of reminiscent of a six-pointed snowflake. But a new study published in Nature details the formation of “square iced.” By sandwiching a thin layer of water between two sheets of graphene and freezing it, the water crystallized into a square lattice rather than the regular hexagonal one. The implications of this work are not exactly crystal clear, but it serves as an excellent example of how little we know about even the most basic of things such as water.
That’s all for this weekend’s Science Week in Review, thanks for reading!