Word of the Day: Antimicrobial
Antimicrobial Having the ability to kill or inhibit the growth of bacteria, viruses, protozoa, fungi, and other microscopic life forms.
Word of the Day: Deoxyribonucleic Acid
Deoxyribonucleic Acid (DNA) DNA is a molecule. It contains your genes. It is a long chain of smaller molecules called bases that repeat in unique patterns. These patterns act as a code to tell your cells how you should look, act, grow, and adapt to your environment. You are you because of your DNA. An identical copy of this very large molecule is present in the center of every single cell in your body – billions of exact copies. The large DNA molecule is not continuous. It is actually in 23 pieces called chromosomes. Each living thing has a unique number of chromosomes – humans have 23.
Diaries of Mars 160 Twin Desert-Arctic Analog Mission: Phase One in Utah Desert
By Anushree Srivastava Crew Biologist – Mars 160 Twin Desert-Arctic Analog Mission Executive Officer and Crew Biologist – Crew 172 Hi Everyone! Here I am with some selected pieces from my diaries written over a period of three months as part of MARS 160 Twin Desert-Arctic Analog Mission and Crew 172. Mars 160 mission recently culminated its first phase at Mars Desert Research Station (MDRS) in the Utah Desert. The second and final phase of this Mars simulation mission will take place at Flashline Mars Arctic Research Station (FMARS) in the High Arctic this summer. Both FMARS and MDRS, founded and administered by The Mars Society, are unique Mars analog habitats, established in 2000 and 2001 respectively. MDRS is located on the San Rafael Swell of southern Utah and FMARS is located near Haughton Impact Crater formed approx. 39 million years ago during the Eocene. The MDRS campus is…
Bacterial Cell Not as Simple as Previously Thought
In this picture you can actually see the remnants cell membrane after scientists froze and broke apart the cells (C). The very small circles are pores in the membrane. Source: PLOS One When we first learn about cells in biology, we are taught that bacterial cells are simple, and animal and plant cells are more complex. Mammalian cells, the cells that make up dogs, humans and all mammals, are “eukaryotes.” Eukaryotes have multiple membranes — one surrounding their innermost section, the nucleus, which protects their DNA and another outer membrane enclosing the entire cell. Bacterial cells, also called “prokaryotes,” have only an outer membrane. However, reality is never so black and white! As it turns out, there are some species of bacteria that have a more complex membrane system resembling the animal-like cells (eukaryotes). One example of these more complex bacteria is Gemmata obscuriglobans. These bacteria are aquatic and can…
Two Galaxy Centers in Terrifyingly Fast Orbits
At the center of the Milky Way Galaxy, there is a supermassive black hole. This is normal — at the center of almost every galaxy there is a black hole that is millions or billions times heavier than our sun. As galaxies move through the universe, they occasionally collide (the Milky Way is currently colliding with the Sagittarius Galaxy) and over a long time(1), eventually the cores of these galaxies crash into each other, resulting in two supermassive black holes orbiting one another. The two black holes will get closer together, orbiting faster and faster as they fall into one another. This phenomenon should be common, based upon how frequently galaxies collide, however, we have never detected any close orbiting supermassive black holes. Due to this lack of evidence, there has been much debate in the scientific community regarding if it were even possible to for black hole orbits to…
Seven Earth-sized Planets Found Around A Star 40 Light Years Away
Today, Nature published the landmark discovery of a system of seven planets around a star named TRAPPIST-1 about 40 light years away. This star is a red dwarf that is much cooler and smaller than our yellow sun; it is about the size of Jupiter. This is the first time that several planets the size of Earth have all been found within the habitable zone, suggesting the possibility that liquid water–and perhaps life–could exist on one of these worlds. The temperature of a planet is related to how close or how far away it is from it’s star. Our planet is 93 million miles from our star, the Sun, and because we exist, we can be sure that the conditions here on Earth support life. The habitable zone is the region around a star where an orbiting planet is able to sustain the presence of liquid water on its surface.…
Unveiling the mysteries of spiral galaxy arms
Galaxies come in all shapes, sizes, and colors. Many galaxies are in the shape of spirals, including our own Milky Way Galaxy. The movement and evolution of these spirals is not well understood in astrophysics. There are a few hypotheses. Originally, these spiral arms were thought to be rigid arms attached to the center of the galaxy. This would imply that every part of the arm rotates around the center of the galaxy at exactly the same pace, like a wood screw being driven into a board. The shape of the arms would also not change much. A competing hypothesis was that the galaxy should be considered a type of fluid, and the stars that make up the galaxy are just being carried through the fluid by gravity, like cereal pieces swirling in milk. We now understand the spiral arms of a galaxy to be a wave. In this wave,…
Short, Tall, or Average: It’s in Your DNA
Source: Wikimedia Commons Genes are bundles of DNA that exist in your cells that affect how you look, grow, and age. Since the human genome was fully decoded in the 1990s, researchers have been working to figure out what all the genes do. Height is one example of a trait that has been investigated. Although height is an inherited trait, it is impossible to pin it down to just one gene. In fact, over 700 different genes have been found to contribute some small amount to your adult height. However, all of these genes together only account for about 20% of how tall you are. Therefore, there must be some undiscovered set of genes, or unknown effects of known genes, that contribute largely to your height. But what are these genes? What is it in our genetic encoding that actually determines how tall we grow? An international team of…
A Few Rare Genes Affect How Tall You Are
Source: Wikimedia Commons Genes are bundles of DNA that exist in your cells that affect how you look, grow, and age. Since the human genome was fully decoded in the 1990s, researchers have been working to figure out what all the genes do. Height is one example of a trait that has been investigated. Although height is an inherited trait, it is impossible to pin it down to just one gene. In fact, over 700 different genes have been found to contribute some small amount to your adult height. However, all of these genes together only account for about 20% of how tall you are. Therefore, there must be some undiscovered set of genes, or unknown effects of known genes, that contribute largely to your height. But what are these genes? What is it in our genetic encoding that actually determines how tall we grow? An international team of over…
The Age and Fate of the Orion Nebular Cloud
Credit: https://arxiv.org/pdf/1605.03600v1.pdf Stars and planets are most often categorized by their mass. In astronomy, the “initial mass function” is used for this categorization. The initial mass function catalogues the number of planets and stars of a certain mass, and creates a diagram of the stars and planets ordered by their size. This initial mass function, abbreviated IMF, gives us clues to many properties about a star system. It can determine the age, the chemistry, and the future destiny of the star system. It can help determine if a star like our sun could exist, and whether planets could exist around it that would have the conditions for life. There is much argument in the astronomy field whether the IMF alone can determine what the future of a star system will look like, or if there are more complex dynamics that determine the fate of the star and the bodies that…
Life Under a Black Sun
Every living thing on our Earth has to thank the Sun for its ability to survive, as it warms the Earth to liveable temperatures. It is hard for us to imagine how a civilization could function without a star shining bright in the sky of its host planet. Scientists in the Czech Republic have been researching if a planet could harness enough energy to run a civilization if the planet were orbiting a black hole instead of a star. This would work in a fundamentally different way than how our planet and civilization work. The sun emits light and UV-radiation, the type of sunshine that causes a sunburn. This light and radiation carry energy that gets used by things like plants and solar panels. Black holes don’t produce light1, hence the name black holes, but they have mind-boggling amounts of gravity, enough to attract light and radiation. There are two…