September 21, 2012
American farmers haven’t needed a satellite this summer to tell them we’re in a drought. The worst dry spell in more than 20 years has had a devastating impact on U.S. crop production.
What’s amazing is that you can see the dryness below ground— from space. NASA’s GRACE mission, which uses two satellites to measure the tug of gravity with unprecedented detail, is sensitive enough to tell when stored groundwater has dried up, based on changes in the total mass of the land over which it orbits.
See the time-lapse map below, then read this fascinating article from NASA’s Earth Observatory. Ten years ago, when GRACE was launched, some hydrologists didn’t think it was possible to measure groundwater from orbit.
March 12, 2012
NASA is getting ready to launch a series of rockets over the U.S. East Coast this week as part of the Anomalous Transport Rocket Experiment (ATREX), which will study ultra-high altitude wind 60-65 miles above the Earth’s surface.
The five sounding rockets all will be launched within five minutes of each other from NASA’s Wallops Flight Facility on Wallops Island, Virginia. Once at altitude, they’ll release a chemical tracer — trimethyl aluminum, which forms a milky white cloud. Cameras at two points, in North Carolina and New Jersey, will monitor the tracers as they move through the thermosphere.
Sounding rockets are generally used for research, most often to take measurements of the upper atmosphere, just as they will in this case. Their light weight allows them to get up to the edge of space without quite hitting orbital velocity. Wallops has a slew of rockets dedicated to this type of research, plus a prime location on the Eastern seaboard. ATREX will be using two Terrier-Improved Malemut rockets, two Terrier-Improved Orions and one Terrier-Oriole.
Studying this region, right around the Kármán line that marks the boundary between Earth’s atmosphere and space, could tell us much about the 200-300 mph winds that blow at that altitude. According to NASA:
This rocket experiment is designed to gain a better understanding of the high-altitude winds and help scientists better model the electromagnetic regions of space that can damage man-made satellites and disrupt communications systems. The experiment will also help explain how the effects of atmospheric disturbances in one part of the globe can be transported to other parts of the globe in a mere day or two.
Maybe the more interesting part is that since the experiment requires clear skies, almost anyone from South Carolina to New Jersey should be able to look up and see the rockets and tracer clouds. The hitch, of course, is that it may be in the middle of the night. The first window for launch opens at 11 pm on March 14 and closes at 6:30 am the next day. If the weather is a no-go, they’ll keep trying each night through April 3. You can keep an eye on the Wallops site for updated launch information.
January 26, 2012
Despite being the strongest solar storm since 2005, this week’s flareup appears to have caused few disruptions on Earth. (As Space.com reports, the Coronal Mass Ejection “hit Earth at an angle, so the electromagnetic burst was largely shielded by the planet’s magnetic field.”)
But the storm did lead some airlines—including Delta, Qantas, and Air Canada—to alter their transpolar routes to reduce potential disruptions to high-frequency radio communication along the way. At least one Qantas flight, reports AvWeb, carried an extra five tons of fuel in order to fly a less southerly route.
We may have gotten off easy. The remarkable electrical effects of solar storms have been recorded in newspapers since British astronomer Richard Carrington noticed a solar eruption in 1859 while sketching sun spots seen through his telescope. Just days later, the northern lights—seen as far south as Cuba—damaged telegraph systems, even setting offices on fire and melting wires. On August 30, 1859, the New York Times included this observation from the superintendent of the Canadian Telegraph Company:
I never, in my experience of fifteen years in the working of telegraph lines, witnessed anything like the extraordinary effect of the Aurora Borealis, between Quebec and Further Point last night. The line was in most perfect order, and well-skilled operators worked incessantly from 8 o’clock last evening till 1 o’clock this morning, to get over in even a tolerably intelligent form about four hundred words of the steamer Indian‘s report for the Associated Press, and at the latter hour so completely were the wires under the influence of the Aurora Borealis, it was found utterly impossible to communicate between the telegraph stations, and the line was closed for the night.
Another solar storm, nearly as strong as what has come to be known as the Carrington event, occurred in 1921. On May 16, 1921, the Los Angeles Times reported that “electrical influences exerted by the Aurora Borealis…continued today to play havoc with telegraph traffic throughout the United States…. For more than an hour before midnight Saturday nearly every telephone wire leading from New York and Chicago was out of condition.”
The New-York Tribune hoped to calm its readers by noting that the sun would soon “turn [its] spotted face away and end earthly wire troubles,” while the New York Times reported disturbances in France: “The operators at the central transmission stations came to the conclusion that a strange force had got into their instruments, for nothing would go right. Morse instruments, instead of making dots and dashes, recorded one long line. Hughes instruments produced words in what might have been an unknown language, and Baudot, of which French telegraphers are proud because it is very intricate, seemed possessed by evil spirits.”
Newcomb Carlton, president of the Western Union Telegraph Company, was quoted in the New York Times as saying: “The magnetic disturbances were much the worst ever experienced. A great many fuses were blown out on our land lines and we had great difficulty with the submarine cables.” The story also reports that the solar storm burned out a telephone station in Sweden, which then contributed to a short circuit in the New York Central signal system, which was followed by a fire in the Fifty-seventh Street signal tower.
In 1989, the Washington Post reported on December 18 that a solar storm—or “titanic temper tantrum”—set off radiation alarms aboard the supersonic Concorde in flight, damaged orbiting satellites, and caused a nine-hour power blackout in most of Canada’s Quebec province.
In comparison, Space.com reports, this week’s solar flare caused “minor disruptions to spacecraft and power grids.”
October 4, 2011
Keith Madden, projectionist and technician at the National Air and Space Museum theater, reports:
“When the [Mineral, Virginia] earthquake struck at 1:51 p.m. on Tuesday, August 23, it unnerved most of our staff and visitors—except patrons in the NASM IMAX® theaters on the Mall and at the Udvar Hazy Center. The timing of the earthquake coincided exactly with thunderous subwoofer action in the Niagara Falls scene in To Fly! at the Lockheed IMAX Theater, and also with the booming space shuttle launch scene in Hubble in 3D at the Airbus IMAX Theater. Patrons in both theaters were oblivious to the earthquake, but many did observe after the show that the sound system was so impressive that their seats shook.
“I too was fooled for a moment. I looked up when I felt the booth floor shake and saw Niagara Falls and thought it was just an everyday occurrence. As it grew in intensity I thought to double-check the subwoofer setting. Only when the heavy equipment rocked back and forth did I realize that this was not just our everyday earth-shaking sound system at work.
“Kyle Lee was the projectionist at the UHC that day, and he too was not sure at first if it was the sound system or something else. Sure enough, at exactly 1:51 p.m. the shuttle launched and the seats shook with up to 105 dB of sonic power. That launch scene was a bit shorter than the earthquake but that explained why not a soul panicked.”
August 25, 2011
According to computer modeling by NASA’s QuakeSim project, Tuesday’s 5.8-magnitude earthquake in central Virginia moved the city of Washington D.C. a whopping 0.02 inches “to the northwest and downward.” The small town of Mineral, near the quake’s epicenter, shifted about 2.8 inches.
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