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No matter how sweaty and sweltering we've been feeling this summer, even our highest temperatures -- 105, 110 degrees -- are nothing compared with a spot roughly 93 million miles from here: the sun.
And the hottest part of the sun is its center, which is at least 10 million degrees Kelvin: roughly 30,000 times hotter than boiling water. So, we're talking major hotness on that star of ours.
On Aug. 23, NASA is launching the second mission in its "Living With a Star" program, which aims to improve our understanding of the sun, and how it affects us humans in space and on Earth.
The upcoming launch will focus on space weather. David Sibeck, a mission scientist at NASA Goddard Space Flight Center in Greenbelt, Md., defines space weather as "the set of effects that happen in space that can affect humans and their technology in space."
It's different from Earth weather, he says, though "we use the same kind of terminology. We have storms in space, but they're caused by disturbances coming out from the sun. Big blobs of charged plasma that can envelop spacecraft and cause short circuits and other effects in those spacecraft."
Now, this "charged plasma" Sibeck talks about dominates interplanetary space. In fact, 99 percent of the universe is made up of this electrified gas. And immediately surrounding our planet, we have two giant rings of highly-radioactive plasma. They're called the Van Allen Radiation Belts, named for the late space scientist, James Van Allen.
"Professor Van Allen and his colleagues at the University of Iowa were among the first to launch rockets into space," Sibeck says. "The rockets carried Geiger counters. But what they found was the Geiger counters suddenly stopped working at a certain height."
Sibeck says there were only two possible explanations. One: "the Geiger counters had broken." Or two: "the space was so radioactive that it was overflowing and overwhelming the Geiger counters."
Number two eventually won out, because these belts are extremely radioactive. So much so, that they actually emit sounds. Professor Donald Gurnett, also of the University of Iowa, recorded and named some of these radiowaves, including "Earth Chorus," "Earth Proton Whistlers" and "Earth Multihop Whistlers."
"[They] are called 'whistlers' because you hear the falling sound of the whistle," Sibeck says. "Because the high-frequency ones travel faster and the low-frequency ones follow along."
Many of the radiation belt sounds bring to mind a chorus of birds, and Sibeck says "that's exactly the right impression to have because the very first people to hear these sounds in the 1920s began to call them things like 'chorus,' or 'morning chorus' -- the sounds you'd hear from a forest in the morning when you wake up and hear the birds."
Sibeck says this month's NASA mission not only will better our understanding of the Radiation Belts, but of space weather, and our ability to predict it, and that's a good thing. Because not only can space weather screw up instruments and astronauts in space, it can mess up stuff on Earth, too! Like, communications, for instance.
"It affects the Earth's ionosphere and just can shut out radio transmission," Sibeck says.
Cell phone signals and short-wave radio broadcasts also can go haywire; even airplane communications can go on the fritz.
And the reason NASA is launching RBSP this year, is because next year's space weather could be the most extreme we've seen in a while.
"Next year will be the peak of the 11-year solar cycle," Sibeck explains. "We expect the most intense activity from the sun, these explosions on the sun sending out enormous blobs of plasma, of charged particle, battering the earth's magnetic field, shaking it up. It's this shaking up and driving it that cause these effects in the radiation belts."
As for how that'll affect life here on earth? Well, get this: down here in Washington, D.C., we may be able to view the aurora borealis, or the Northern Lights. Farther north, the effects may be more severe.
"In the past, there have been surges in electrical power lines that have blown out transformers and caused massive blackouts," Sibeck says.
As for what the $650 million RBSP mission actually entails, on Aug. 23, at 4 a.m. at Cape Kennedy, NASA will launch two Radiation-Belt Storm Probe satellites on a single Atlas 5 rocket that will carry them up a distance of about a tenth of the way to the moon -- in other words, to the heart of the earth's radiation belts.
The satellites were built by the Johns Hopkins University Applied Physics Laboratory, and as these twin discs spin away from the rocket, their instruments will measure those dangerous, whistling particles, from the lowest energies to the highest energies, so we can finally understand the complete environment around the Earth.
The satellites are expected to send back measurements for two years. And as they do, Sibeck hopes to answer questions that have plagued him and his colleagues for years. Where do the radiation belts' dangerous, energetic particles come from? Where do they move to? How do they move around? Where would you find them on any given day? And finally, what removes them?
"Because the radiation belts, the intensity of particles, rises and falls over the course of an hour, over the course of a day, over the course of a month," Sibeck says.
Sibeck says answering these questions would be a defining moment for him... and for all of us, really. Because by understanding more about space weather and radiation belts, we could understand more about the entire universe. And we can thank our lucky stars for that!
[Music: "Telstar" by The Ventures from Greatest Hits]
Photos: Solar Storms