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The further we move away from a heat source, the cooler the air gets... the surface of the Sun starts at 6000 degC, but over a short distance of only a few hundred kilometers, it suddenly heats up to more than a million degrees, becoming its atmosphere, or corona...The popular theories are based on heating caused by turbulence, and heating caused by a type of magnetic wave called ion cyclotron waves.“Both, however, have some problem – turbulence struggles to explain why Hydrogen, Helium and Oxygen in the gas become as hot as they do, while electrons remain surprisingly cold; while...

The visible surface of the Sun, or the photosphere, is around 6,000°C. But a few thousand kilometers above it – a small distance when we consider the size of the Sun – the solar atmosphere, also called the corona, is hundreds of times hotter, reaching a million degrees celsius or higher. This spike in temperature, despite the increased distance from the Sun’s main energy source, has been observed in most stars, and represents a fundamental puzzle that astrophysicists have mulled over for decades. In 1942, the Swedish scientist Hannes Alfvén proposed an explanation. He theorized that magnetized waves of plasma...

...why is its outer atmosphere hotter than its fiery surface? University of Michigan researchers believe they have the answer, and hope to prove it with help from NASA's Parker Solar Probe. In roughly two years, the probe will be the first manmade craft to enter the zone surrounding the sun where heating looks fundamentally different than what has previously been seen in space. This will allow them to test their theory that the heating is due to small magnetic waves travelling back and forth within the zone... Such high temperatures cause the solar atmosphere to swell to many times the...

Venus has an “electric wind” strong enough to remove the components of water from its upper atmosphere, which may have played a significant role in stripping Earth’s twin planet of its oceans, according to new results from ESA’s (European Space Agency) Venus Express mission by NASA-funded researchers. “It’s amazing, shocking,” said Glyn Collinson, a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We never dreamt an electric wind could be so powerful that it can suck oxygen right out of an atmosphere into space. This is something that has to be on the checklist when we go looking...

Explanation: Why does this star have so few heavy elements? Stars born in the generation of our Sun have an expected abundance of elements heavier than hydrogen and helium mixed into their atmospheres. Stars born in the generation before our Sun, Population II stars, the stars that created most of the heavy elements around us today, are seen to have some, although less, elements heavier than H and He. Furthermore, even the elusive never-seen first stars in the universe, so-called Population III stars, are predicted to have a large mass and a small but set amount of heavy elements. Yet...

Increasing solar activity and the threat that coronal mass ejections (CME) pose to Earth has prompted NASA to convene a news briefing at its Headquarter building in Washington on Thursday afternoon. Thursday's briefing has been arranged, space agency officials say, in light of new information coming from NASA's Solar Terrestrial Relations Observatory (STEREO), spacecraft and other NASA probes. The briefing will feature new details about the structure of solar storms and the impact they have on Earth... A massive solar flare, the largest recorded in four years, occurred last Tuesday prompting fears the blast could result in some disruption to...

Greenbelt - The National Aeronautics and Space Administration's Solar and Heliospheric Observatory (SOHO) captured a spectacular image of a comet diving into the sun just as a coronal mass ejection came out on the right side. On one hand, the universe can be one of shimmering beauty, harmony and order. On the other hand, there can be utter entropy, randomness and sheer coincidences. The latter is what happened between our sun and a comet last week. According to NASA’s SOHO, a bright comet, most likely from the Kreutz family of comets, which was discovered by amateur astronomer Sergey Shurpakov, slammed...

Enlarge Image In the eye of the beholder. Sharper views of the sun at a variety of wavelengths are revealing small jets from the solar surface that are helping heat the overlying corona to 1 million˚C. Credit: Bart De Pontieu The mystery of the solar corona is obvious enough. The vanishingly thin atmosphere of the sun—the wispy stuff that can be glimpsed faintly during total solar eclipses—simmers at 1 million˚C, 200 times hotter than the "fire" beneath it. What gives? Researchers now believe they have caught the sun in the act of heating bits of itself to coronal temperatures...