#Comet #ISON entered the field of view of the HI-1 camera on NASA's Solar Terrestrial Relations Observatory, or STEREO, on Nov. 21, 2013, and the comet shows up clearly, appearing to still be intact.
Dark "clouds" coming from the right are more dense areas in the solar wind, causing ripples in Comet Encke's tail. Using comet tails as tracers can provide valuable data about solar wind conditions near the sun.
Image Credit: Karl Battams/NASA/STEREO/CIOC
#cometISON #nasa #space
Antarctic Ozone Hole Slightly Smaller than Average This Year: The ozone hole that forms each year in the stratosphere over Antarctica was slightly smaller in 2013 than average in recent decades, according to NASA satellite data. This video shows the latest false-color view of total ozone over the Antarctic pole. The purple and blue colors are where there is the least ozone, and the yellows and reds are where there is more ozone.
The ozone hole is a seasonal phenomenon that starts to form during the Antarctic spring (August and September). The September-October 2013 average size of the hole was 8.1 million square miles (21 million square kilometers). For comparison, the average size measured since the mid-1990s when the annual maximum size stopped growing is 8.7 million square miles (22.5 million square kilometers). However, the size of the hole in any particular year is not enough information for scientists to determine whether a healing of the hole has begun.
What's it like to fly along with the SOFIA mission? In this time-lapse, you see the Stratospheric Observatory for Infrared Astronomy (SOFIA) telescope during a scientific observation gathering mission. SOFIA is a heavily modified 747SP aircraft that carries a telescope with an effective diameter of 100 inches (2.5 meters) to altitudes above 39,000 feet (12 km), beyond the obscuring layer of water vapor in Earth's atmosphere.
In this video, it appears SOFIA moves — but in reality, the telescope stays extremely stable and steady during observations. The motion seen in this video is actually the airplane moving around the telescope, which is steady. The telescope is designed this way to account for turbulence so that it is stable for accurate observations.
SOFIA is a joint project of NASA and the German Aerospace Center (DLR) that is based at NASA's Dryden Aircraft Operations Facility in Palmdale, Calif. The SOFIA Science Center is located at NASA Ames Research Center in Mountain View, Cailf.
Video credit: Dr. Daniel Angerhausen, Rensselaer Polytechnic Institute
This summer's sea ice minimum in the Arctic is still the sixth lowest extent of the satellite record and is 432,000 square miles (1.12 million square kilometers) lower than the 1981-2010 average, roughly the size of Texas and California combined.
The ice cap covering the Arctic Ocean shrinks and expands with the passing of the seasons, melting in the summer and refreezing during the long, frigid Arctic winter. This year, cooler weather in the spring and summer led to a late start of the melt season and overall less melt.
This animation shows the daily Arctic sea ice extent and seasonal land cover change through Sept. 12, 2013, the day before NSIDC estimated that sea ice reached its minimum area of extent. The data was provided by the Japan Aerospace Exploration Agency from their AMSR2 instrument aboard the GCOM-W1 satellite.
This year, Arctic temperatures were 1.8 to 4.5 degrees Fahrenheit (1 to 2.5 degrees Celsius) lower than average, according to NASA's Modern Era Retrospective analysis for Research and Applications, a merging of observations and a modeled forecast. The colder temperatures were in part due to a series of summer cyclones. In August 2012, a big storm caused havoc on the Arctic Ocean’s icy cover, but this summer’s cyclones have had the opposite effect: under cloudier conditions, surface winds spread the ice over a larger area.
Image Credit: NASA Goddard's Scientific Visualization Studio/Cindy Starr
