Upload new images. The image library for this site will open in a new window.
Upload new documents. The document library for this site will open in a new window.
Show web part zones on the page. Web parts can be added to display dynamic content such as calendars or photo galleries.
Choose between different arrangements of page sections. Page layouts can be changed even after content has been added.
Move this whole section down, swapping places with the section below it.
Check for and fix problems in the body text. Text pasted in from other sources may contain malformed HTML which the code cleaner will remove.
Accordion feature turned off, click to turn on.
Accordion featurd turned on, click to turn off.
Change the way the image is cropped for this page layout.
Cycle through size options for this image or video.
Align the media panel to the right/left in this section.
Open the image pane in this body section. Click in the image pane to select an image from the image library.
Open the video pane in this body section. Click in the video pane to embed a video. Click ? for step-by-step instructions.
Remove the image from the media panel. This does not delete the image from the library.
Remove the video from the media panel.
This is UD's "outside" neutron monitor at the South Pole. UD currently operates nine neutron monitors three in Antarctica (one inside and one outside South Pole Station, and one at McMurdo Station) and six in northern climes. The first neutron monitor installed at the South Pole has been in operation almost continuously since 1964.
Massive explosions on the sun unleash radiation that could kill astronauts in space.
Now, researchers from the U.S. and South Korea have developed a warning system capable of forecasting the radiation from these violent solar storms nearly three hours (166 minutes) in advance, giving astronauts, as well as air crews flying over Earth's polar regions, time to take protective action.
Physicists from the University of Delaware and from Chungnam National University and Hanyang University developed the system and report on it in Space Weather: The International Journal of Research and Applications, published by the American Geophysical Union. The research article also is selected as an "Editor's Highlight."
Prof. John Bieber at UD's Bartol Research Institute, based in the Department of Physics and Astronomy, directed the scientific project. The article's lead author is Su Yeon Oh, a postdoctoral researcher from Chungnam National University, who worked with Bieber on the project at UD.
"Traveling nearly at the speed of light, it takes just 10 minutes for the first particles ejected from a solar storm to reach Earth," Bieber says. These sun storms can cover thousands of miles on the sun, like a wave of exploding hydrogen bombs.
The researchers used data collected by two neutron monitors installed years ago at the South Pole by UD one inside and one outside the Amundsen-Scott South Pole Station to determine the intensity of the high-energy, fast-moving particles that arrive to Earth first from solar storms. These particles can carry energies over 500 megaelectron volts (MeV) that's over 500 million electron volts.
By examining the properties of these first-arriving particles, the scientists can make useful predictions about the slower-moving, yet more dangerous particles to follow.
"These slower-moving particles are more dangerous because there are so many more of them. That's where the danger lies," Bieber explains.
When these firstcomer, positively charged particles, or protons, hit an air molecule in Earth's atmosphere, they blast apart into tiny pieces, which, in turn, slam into other air molecules, and so on. Neutrons, neutrally charged particles, are produced as part of this cascading event.
From measurements of the neutrons produced in past solar events taken by UD's neutron monitors at South Pole, the scientists calculated the energy of the first-arriving protons and, from that, estimated the intensity of the later-arriving, more dangerous particles.
The authors compared their predictions for 12 solar events against observations made by geosynchronous satellites, achieving good agreement for protons with energies higher than 40 to 80 megaelectron (million) volts.
Depending on the protons' energy, the system provides a warning time up to 166 minutes. That would give astronauts on deep space flights time to seek out an armored area in their spacecraft, Bieber says, and pilots flying in Earth's polar regions, where the planet's protective magnetic field is weaker, time to reduce their altitude.
Move this whole section up, swapping places with the section above it.
NASA's Solar Dynamics Observatory (SDO) captured this M5.6 class solar flare on July 2, 2012, at 6:52 a.m. EDT. The flare, which came from a large sunspot called AR1515 in the sun's southern hemisphere, caused brief radio interference over Europe.
The sun is now moving into a peak period of solar storm activity, which generally occurs every 11 years. The solar storms, flares and coronal mass ejections threaten the electrical system on Earth in addition to some astronauts and fliers.
"If you're in a plane flying over the poles, there is an increased radiation exposure comparable to having an extra chest X-ray you weren't planning on," says Bieber. "However, if you're an astronaut on the way to the moon or Mars, it's a big problem. It could kill you."
Most astronauts have flown in low Earth orbit in recent years, but if we go back to the moon or decide to send humans to Mars, we need to think about these things, Bieber says. According to him, some of the Apollo astronauts were just lucky.
"Somehow they got these moon launches between big solar flares that would have killed them right then and there," Bieber notes.
The study's authors also included John Clem, Paul Evenson and R. Pyle from UD; Yu Yi from Chungnam University; and Y.-K. Kim, Hanyang University.
The research was funded by the National Research Foundation of Korea through the South Korean government and by the U.S. National Science Foundation, NASA and the NASA/EPSCoR program.