Understanding Physics of Fire Imperative for Space Safety
Unlike flames on Earth, which have a tear-drop shape caused by buoyant air rising in a gravitational field, flames in space curl themselves into tiny balls. Untethered by gravity, they flit around as if they have minds of their own. More than one astronaut conducting experiments for researchers on Earth below has been struck by the way flameballs roam their test chambers in a lifelike search for oxygen and fuel.
Biologists confirm that fire is not alive. Nevertheless, on Aug. 21, astronaut Reid Wiseman on the ISS witnessed some of the best mimicry yet.
Objects in space tend to spin — and spin in a way that’s totally different from the way they spin on earth. Understanding how objects are spinning, where their centers of mass are and how their mass is distributed is crucial to any number of actual or potential space missions, from cleaning up debris in the geosynchronous orbit favored by communications satellites to landing a demolition crew on a comet.
In a forthcoming issue of the Journal of Field Robotics, MIT researchers will describe a new algorithm for gauging the rotation of objects in zero gravity using only visual information. And at the International Conference on Intelligent Robots and Systems this month, they will report the results of a set of experiments in which they tested the algorithm aboard the International Space Station.
A team of scientists led by the Carnegie Institution’s Jacqueline Faherty has discovered the first evidence of water ice clouds on an object outside of our own Solar System. Water ice clouds exist on our own gas giant planets — Jupiter, Saturn, Uranus and Neptune — but have not been seen outside of the planets orbiting our Sun, until now. Their findings are published by The Astrophysical Journal Letters.
At the Las Campanas Observatory in Chile, Faherty, along with a team including Carnegie’s Andrew Monson, used the FourStar near infrared camera to detect the coldest brown dwarf ever characterized. Their findings are the result of 151 images taken over three nights and combined. The object, named WISE J085510.83-071442.5, or W0855, was first seen by NASA’s Wide-Field Infrared Explorer mission and published earlier this year. But it was not known if it could be detected by Earth-based facilities.
A small asteroid, designated 2014 RC, will safely pass very close to Earth on Sunday, Sept. 7, 2014. At the time of closest approach, based on current calculations to be about 2:18 p.m. EDT (11:18 a.m. PDT / 18:18 UTC), the asteroid will be roughly over New Zealand. From its reflected brightness, astronomers estimate that the asteroid is about 60 feet (20 meters) in size.
Asteroid 2014 RC was initially discovered on the night of August 31 by the Catalina Sky Survey near Tucson, Arizona, and independently detected the next night by the Pan-STARRS 1 telescope, located on the summit of Haleakalā on Maui, Hawaii. Both reported their observations to the Minor Planet Center in Cambridge, Massachusetts. Additional follow-up observations by the Catalina Sky Survey and the Univ. of Hawaii 88-inch (2.2-meter) telescope on Mauna Kea confirmed the orbit of 2014 RC.
One of the most visible signs of climate change in recent years was not even visible at all until a few decades ago. The sea ice cap that covers the Arctic Ocean has been changing dramatically, especially in the last 15 years. Its ice is thinner and more vulnerable – and at its summer minimum now covers more than 1 million fewer square miles than in the late 1970s. That’s enough missing ice to cover Alaska, California and Texas.
A key part of the story of how the world was able to witness and document this change centers on meticulous work over decades by a small group of scientists at NASA’s Goddard Space Flight Center. Late nights in mainframe rooms, double- and triple-checking computer printouts, processing and re-processing data – until the first-ever accurate atlases of the world’s sea ice were published.
European space officials say they’re investigating whether the inaccurate deployment of two satellites will complicate their efforts to develop a new Galileo satellite navigation system that would rival America’s GPS network.
The European Space Agency and launch company Arianespace say the satellites ended up in off-target orbits after being launched Friday from Kourou, French Guiana, aboard a Soyuz rocket.
The moon appears to be a tranquil place, but modeling done by Univ. of New Hampshire and NASA scientists suggests that, over the eons, periodic storms of solar energetic particles may have significantly altered the properties of the soil in the moon’s coldest craters through the process of sparking. This find could change our understanding of the evolution of planetary surfaces in the solar system.
The study, published recently in the Journal of Geophysical Research: Planets, proposes that high-energy particles from uncommon, large solar storms penetrate the moon’s frigid, polar regions and electrically charge the soil. The charging may create sparking, or electrostatic breakdown, and this “breakdown weathering” process has possibly changed the very nature of the moon’s polar soil, suggesting that permanently shadowed regions, which hold clues to our solar system’s past, may be more active than previously thought.
NASA’s Voyager 2 spacecraft gave humanity its first close-up look at Neptune and its moon Triton in the summer of 1989. Like an old film, Voyager’s historic footage of Triton has been “restored” and used to construct the best-ever global color map of that strange moon. The video may be watched here. The map, produced by Paul Schenk, a scientist at the Lunar and Planetary Institute in Houston, has also been used to make a movie recreating that historic Voyager encounter, which took place 25 years ago, on August 25, 1989.
The new Triton map has a resolution of 1,970 feet (600 meters) per pixel. The colors have been enhanced to bring out contrast but are a close approximation to Triton’s natural colors. Voyager’s “eyes” saw in colors slightly different from human eyes, and this map was produced using orange, green and blue filter images.
Toothpaste Ingredient May Have Formed in Dying Stars
The fluorine that is found in products such as toothpaste was likely formed billions of years ago in now dead stars of the same type as our sun. This has been shown by astronomers at Lund Univ. in Sweden, together with colleagues from Ireland and the U.S.
Fluorine can be found in everyday products such as toothpaste and fluorine chewing gum. However, the origins of the chemical element have been somewhat of a mystery. There have been three main theories about where it was created. The findings now presented support the theory that fluorine is formed in stars similar to the sun but heavier, towards the end of their existence. The sun and the planets in our solar system have then been formed out of material from these dead stars.
There is nothing like a head cold to make us feel a little dazed. We get things like colds and the flu because of changes in our immune system. Researchers have a good idea what causes immune system changes on Earth — things like stress, inadequate sleep and improper nutrition. But the results of two NASA collaborative investigations — Validation of Procedures for Monitoring Crewmember Immune Function (Integrated Immune) and Clinical Nutrition Assessment of ISS Astronauts, SMO-016E (Clinical Nutrition Assessment) — recently published in the Journal of Interferon & Cytokine Research suggest that spaceflight may temporarily alter the immune system of crew members flying long duration missions aboard the International Space Station. This is of concern as NASA looks ahead to six-month and multiple-year missions to asteroids, the moon and Mars because something as simple as a cold or the flu can be risky business in space.
Image of the Week: Astronauts Release Tiny Satellite
Spacewalking astronauts launched a tiny Peruvian research satellite Monday, setting it loose on a mission to observe Earth.
Russian Oleg Artemiev cast the four-inch box off with his gloved right hand as the International Space Station sailed 260 miles above the cloud-flecked planet. The nanosatellite gently tumbled as it cleared the vicinity of the orbiting complex, precisely as planned.
NASA astronaut Reid Wiseman, Expedition 40 flight engineer, has installed Capillary Channel Flow (CCF) experiment hardware in the Microgravity Science Glovebox (MSG) located in the Destiny laboratory of the International Space Station. CCF is a versatile experiment for studying a critical variety of inertial-capillary dominated flows key to spacecraft systems that cannot be studied on the ground.
An international team of sky scholars, including a key researcher from Johns Hopkins, has produced new maps of the material located between the stars in the Milky Way. The results should move astronomers closer to cracking a stardust puzzle that has vexed them for nearly a century.
The maps and an accompanying journal article appear in today’s issue of the journal Science. The researchers say their work demonstrates a new way of uncovering the location and eventually the composition of the interstellar medium — the material found in the vast expanse between star systems within a galaxy.
Scientists say seven microscopic particles collected by NASA’s comet-chasing spacecraft, Stardust, appear to have originated outside our solar system. If confirmed, this would be the world’s first sampling of contemporary interstellar dust.
"They are very precious particles," the team leader, physicist Andrew Westphal of UC Berkeley, said in a statement.
A Purdue Univ. student team has designed, built and tested a critical part of a new a rocket engine as part of a NASA project to develop spacecraft technologies needed to land on the moon, Mars and other cosmic venues.
The students are making a central part of the new engine - called the thrust chamber or combustor — as part of NASA’s Project Morpheus. The project aims to develop a prototype vehicle capable of vertical takeoff and landing using an autonomous system.