This video compresses about an hour of solar activity around a sunspot to a little over ten seconds.
Via APOD:
The Sun’s surface keeps changing. The above movie shows how the Sun’s surface oozes during a single hour. The Sun’s photosphere has thousands of bumps called granules and usually a few dark depressions called sunspots.
APOD has a spectacular video of a comet impacting the Sun followed by a coronal mass ejection.
Here’s the latest report from NASA regarding UARS, the enormous satellite that will re-enter Earth’s atmosphere sometime today or tomorrow.
NASA’s Upper Atmosphere Research Satellite, or UARS, is expected to re-enter Earth’s atmosphere late Sept. 23 or early Sept. 24 Eastern Daylight Time, almost six years after the end of a productive scientific life. Although the spacecraft will break into pieces during re-entry, not all of it will burn up in the atmosphere.
The risk to public safety or property is extremely small, and safety is NASA’s top priority. Since the beginning of the Space Age in the late-1950s, there have been no confirmed reports of an injury resulting from re-entering space objects. Nor is there a record of significant property damage resulting from a satellite re-entry.
It is still too early to say exactly when UARS will re-enter and what geographic area may be affected, but NASA is watching the satellite closely and will keep you informed. Visit this page for updates on the satellite’s orbital track and predicted re-entry date.
Update #10
Fri, 23 Sep 2011 07:45:08 AM MST
As of 10:30 a.m. EDT on Sept. 23, 2011, the orbit of UARS was 100 miles by 105 miles (160 km by 170 km). Re-entry is expected late Friday, Sept. 23, or early Saturday, Sept. 24, Eastern Daylight Time. Solar activity is no longer the major factor in the satellite’s rate of descent. The satellite’s orientation or configuration apparently has changed, and that is now slowing its descent. There is a low probability any debris that survives re-entry will land in the United States, but the possibility cannot be discounted because of this changing rate of descent. It is still too early to predict the time and location of re-entry with any certainty, but predictions will become more refined in the next 12 to 18 hours.
This is an interesting animation showing a three-axis presentation of recent solar coronal mass ejections. You can click on the image for the full-sized animation.
From SpaceWeather.com:
FOUR CMEs: On Sept. 19th, the STEREO-SOHO fleet of spacecraft surrounding the sun detected six coronal mass ejections (CMEs). Two of the clouds rapidly dissipated. The remaining four, however, are still intact and billowing through the inner solar system.
According to analysts at the Goddard Space Weather Lab, who prepared the movie, one CME should hit Mercury on Sept. 20th at 05:40 UT while another delivers a glancing blow to Earth’s magnetic field on Sept. 22nd at 23:00 UT. All impact times have an uncertainty of plus or minus 7 hrs.
Old Sol continues to increase in activity, moving toward the eleven-year peak. Solar activity affects climate, auroras, (possibly) the electric power grid and radio propagation. For an impressive animation of this comparison, play the video below. To view the full-sized video, click here.
From SOHO Pick of the Week:
A side-by-side comparison of the Sun from precisely two years ago (left, from SOHO) to the present (right, from Solar Dynamics Observatory) dramatically illustrates just how active the Sun has become (Mar. 27-28, 2011). Viewed in two similar wavelengths of extreme ultraviolet light, the Sun now sports numerous active regions that appear as lighter areas that are capable of producing solar storms. Two years ago the Sun was in a very quiet period (solar minimum). The Sun?s maximum period of activity is predicted to be around 2013, so we still have quite a ways to go.
About 13 years ago while working for the aerospace company that produced this aircraft, I had the privilege of working on prototype avionics systems for pilotless aircraft systems like this. Video taken in the vicinity of Edwards AFB in California’s high desert.
From Fox News:
The U.S. Navy said it made a breakthrough in drone technology with the first flight of the X-47B, a bat-winged unmanned jet designed to take off and land from an aircraft carrier, one of the most complex and difficult feats in aviation.
From the STEREO website:
February 6, 2011: It’s official: The sun is a sphere.
On Feb. 6th, NASA’s twin STEREO probes moved into position on opposite sides of the sun, and they are now beaming back uninterrupted images of the entire star—front and back.
“For the first time ever, we can watch solar activity in its full 3-dimensional glory,” says Angelos Vourlidas, a member of the STEREO science team at the Naval Research Lab in Washington, DC.
“This is a big moment in solar physics,” says Vourlidas. “STEREO has revealed the sun as it really is–a sphere of hot plasma and intricately woven magnetic fields.”
Each STEREO probe photographs half of the star and beams the images to Earth. Researchers combine the two views to create a sphere. These aren’t just regular pictures, however. STEREO’s telescopes are tuned to four wavelengths of extreme ultraviolet radiation selected to trace key aspects of solar activity such as flares, tsunamis and magnetic filaments. Nothing escapes their attention.
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