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Mon, 20 Feb 2017
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Scientists find one of the largest known dinosaur footprints in Gobi Desert

© Sophie Weiner
A team of scientists from Japan and Mongolia has announced the discovery of one of the largest dinosaur footprints that has ever been documented.

According to the Washington Post, researchers found the prints - one of which measures about 42-inches long and 30-inches across - in the Gobi Desert about two months ago.

In addition to the size, the fossil is considered to be fairly well-preserved with claw imprints that are still visible. Archaeologists suspect the mark was made by a massive dinosaur known as a Titanosaur which is believed to have exceeded 100-feet in length and 65-feet in height. They think the large creature may have stepped in some mud, and the hole was quickly filled in with sand or other materials to preserve the impression.

A geologic analysis of the adjacent area has traced the specimen to the Upper Cretaceous period which dates back around 70 million to 90 million years ago.

Researchers are currently looking for any remains from the dinosaur that could have made the footprint.

Solar Flares

Ice, ice maybe: Mars discovery baffles scientists, suggests liquid water impossible

© NASA
The new research means scientists will have to dig deeper to explain evidence of water on the planet.

A Mars rover has caused new confusion over theories about water on Mars after studying rocks which appear to both prove and disprove current ideas about liquid on the red planet's surface.

For ancient Mars to accommodate water, conditions on the surface of the Red Planet would have had to be much warmer than today and with greater carbon dioxide levels forming a protective greenhouse-gas blanket.

However, new research from NASA has thrown further confusion into theories about water on Mars after the Curiosity rover uncovered rocks indicating the existence of a lake - but no signs of the carbon levels required to keep that water unfrozen.

Cloud Grey

Mesmerizing NASA image shows clouds carved by 'gravity waves'

© NASA Goddard Space Flight Center / Flickr
Nasa's Goddard Space Flight Center shared a fascinating image of rippling clouds perfectly parting above the South Georgia and South Sandwich Islands due to gravitational waves.

The blanket of clouds ripple as they cut around the British islands in the southern Atlantic ocean "like a ship carving its way through the sea" by a phenomenon known as "gravity waves".

Gravity waves are formed by the rise and fall of colliding air. Here, moist air from the ocean is pushed down by gravity but then forced back up again by the dry air below rising from from the islands.

The movement keeps repeating over and again, creating a stunning pattern in the clouds.

Bug

Bacterial tribalism: Families of bacteria kill unrelated cells to protect their territory

© University of Edinburgh
Two strains of warring cholera bacteria.
A grisly method by which bacteria dispatch their distant relatives also creates conditions in which the attackers can thrive, research has found.

Families of bacteria cells are known to kill adjacent, unrelated cells by injecting them with toxins - now researchers have found that cells which compete in this way are able to flourish.

Their approach creates surviving pockets of closely related bacteria with a common interest in ensuring their collective genes are passed on to future generations.

The bugs live alongside one another, cooperating to share tasks and resources such as nutrients.

Unrelated microbes, which might cheat by taking resources without contributing, are excluded from the group.

Scientists carried out experiments and created mathematical models of cholera bacteria to better understand how microbes organise themselves in their typically packed populations.

They found that the stabbing tactic - which has no effect on genetically similar relatives - helps create clusters of bacteria that cooperate with each other.

Comment: The importance of sharing: Bacteria which do not contribute are excluded from nutrient exchanges


Airplane Paper

The newest micro air vehicle, Bat Bot, can fly autonomously

© Caltech
Micro Air Vehicles (MAV) are the official name for the growing array of tiny robots that have begun to take flight. Increasing miniaturization has led to an even smaller sub-group of drones called NAV (nano air vehicles) which have been commissioned to provide new solutions in the areas of search and rescue, hazardous exploration, military surveillance, climate mapping, and traffic monitoring - to name a few of the slated functions. Some of these NAV include mapleseed drones, sparrow drones, dragonfly drones and one called RoboBee. The reconstruction of nature is seen by researchers as the best way to introduce MAV and NAV on a wide scale.

The latest in this developing drone menagerie appears to represent the next stage of evolution, a sophisticated miniature drone modeled after a bat that developers are simply calling Bat Bot. As featured by Popular Mechanics:
Bat Bot is nothing short of an engineering marvel. It weighs in at only 3.3 ounces—about as heavy of two golf balls. With a silicone membrane stretched over its carbon-fiber skeleton, a head crammed with an on-board computer and sensors, and five micro-sized motors strung along its backbone, Bat Bot is capable of autonomous, flapping flight. Designed by trio of roboticists led by Soon-Jo Chung at Caltech, it was unveiled today in the journal Science Robotics.

Comet 2

Comet 45P approaches Earth - Closest approach on Feb. 11th

© Michael Jäger
A small comet named "45P/Honda-Mrkos-Pajdusakova" (45P for short) is approaching Earth. At closest approach on Feb. 11th, the comet will be 7.4 million miles from our planet, visible in binoculars and small telescopes. This is what it looks like (image on the left).

Michael Jäger of Stixendorf, Austria, took the picture on Dec. 31, 2016, just as the comet was swinging around the sun en route to Earth. Since then 45P's icy nucleus has been heated by solar radiation, causing it to spew brightening jets of gas into the comet's green atmosphere. Why green? Because the comet's vaporizing nucleus emits diatomic carbon, C2, a gas which glows green in the near-vacuum of space.

According to the Minor Planet Center, this is the 8th closest pass of any comet in the modern era (since ~1950, when modern technology started being used to study comets). It will only be 31 times farther from Earth than the Moon.

Interestingly, 45P made an even closer approach on its previous orbit (23 lunar distances), so it is also on the list as the 5th closest.

Proximity makes the comet bright despite its small size. Forecasters say 45P could be on the verge of naked eye visibility (6th magnitude) when it emerges into the pre-dawn sky later this week. The best time to look is during the dark hours before sunrise between Feb 9th and 12th. The comet will be racing through the constellation Hercules high in the eastern sky. Sky maps: Feb. 9, 10, 11, 12.

Got a great picture? First, submit it to Spaceweather.com. Next, send it to the Planetary Science Institute, which is collecting amateur images to help professional researchers study Comet 45P. More resources: 3D Orbit, Ephemeris.

Brain

This is your brain on spaceflight

© Kate Whitley, Wellcome Images
Scientists know that extended periods of time spent in space can have effects on the human body, caused by altered vestibular inputs and lack of gravity. But what happens to your brain in space?

A new study from University of Michigan researchers used MRI scans to examine how astronauts' brains compress and expand in spaceflight. The findings could have implications for treating other health conditions that affect brain function.

The retrospective follow-up study is believed to be the first to examine structural changes during spaceflight. Results show that the volume of gray matterincreased or decreased, and the extent of the alteration depended on the length of time spent in space.

GRAY MATTER ALTERATIONS

Researchers looked at structural MRIs in 12 astronauts who spent two weeks as shuttle crew members, and 14 who spent six months on the International Space Station. All experienced increases and decreases in gray matter in different parts of the brain.

Comment: Further reading:


Info

Radioisotope dating technique flawed; suggest new study

© Howstuffworks
A diagram showing how carbon-14 gets made and how it gets incorporated into fossils.
An oversight in a radioisotope dating technique used to date everything from meteorites to geologic samples means that scientists have likely overestimated the age of many samples, according to new research from North Carolina State University.

To conduct radioisotope dating, scientists evaluate the concentration of isotopes in a material. The number of protons in an atom determines which element it is, while the number of neutrons determines which isotope it is. For example, strontium-86 has 38 protons and 48 neutrons, whereas strontium-87 has 38 protons and 49 neutrons. Radioactive elements, such as rubidium-87 (but not strontium-86 or strontium-87), decay over time. By evaluating the concentrations of all of these isotopes in a rock sample, scientists can determine what its original make-up of strontium and rubidium were. Then, by assessing the isotope concentrations of rubidium and strontium, scientists can back-calculate to determine when the rock was formed.

The three isotopes mentioned can be used for dating rock formations and meteorites; the method typically works best on igneous rocks.

But it's not quite that straight-forward. The data from radioisotope analysis tends to be somewhat scattered. So, researchers "normalize" the data by making a ratio with strontium-86, which is stable -- meaning it doesn't decay over time.

Rocket

US government investigation of SpaceX rockets reveals dangerous defects in propulsion systems

© Gene Blevins / Reuters
A government investigation into SpaceX has revealed concerns that their rockets have potentially dangerous defects, according to reports. This could majorly affect the company's plans to transport astronauts in the coming years.

Investigators from the Government Accountability Office (GAO), which is charged with conducting audits on behalf of Congress, identified persistent problems with the propulsion system, a vital component of the rocket.

The Wall Street Journal claims to have seen the draft report citing persistent cracking of turbine blades - responsible for rapidly pumping huge amounts of fuel into the rocket engines - to be a serious flaw in the company's flagship Falcon 9 rockets.

The flawed parts of the rocket are thought to be of major concern to the GAO and NASA, with the latter reportedly warning SpaceX that the cracks pose an unacceptable risk to personnel onboard.

Monkey Wrench

Reprograming microbes: Engineered bacteria produce rare & commercially useful compounds in large quantities

© Christine Daniloff/MIT
MIT spinout Manus Bio has created a low-cost process for engineering microbes with complex metabolic pathways borrowed from plants, which can produce an array of rare and expensive ingredients used to manufacture noncaloric beverages, perfumes, toothpastes, detergents, pesticides, and even therapeutics, among other products.
Using advanced fermentation technology, industrial biotech startup Manus Bio hopes to make manufacturing flavors, fragrances, and other products greener and more cost-effective—and maybe create new products in the process.

The MIT spinout has created a low-cost process for engineering microbes with complex metabolic pathways borrowed from plants, which can produce an array of rare and expensive ingredients used to manufacture noncaloric beverages, perfumes, toothpastes, detergents, pesticides, and even therapeutics, among other products. Moreover, the reprogrammed microbes allow for more control in identifying and extracting compounds along the metabolic pathway, which could lead to discoveries of new compound ingredients.

Most recently, Manus has recreated a natural plant process in microbes to cheaply produce mass quantities of a coveted stevia plant compound for a zero-calorie sweetener, called Rebaudioside M (Reb M), that's noted for being much sweeter than today's commercial alternatives. In nature, only .01 percent of the compound can be extracted from the stevia plant, so companies extract a more abundant but more bitter compound.

Manus, on the other hand, has engineered bacteria to mimic the stevia plant's metabolic pathway. When put through the startup's fermentation process, the bacteria produced the compound at greater than 95 percent purity.