Snippet: Will the Earth be Safe From Solar Expansion? The Outlook Isn’t Great…

As the Sun runs out of fuel, it will swell… but will it swell enough to swallow the Earth? Image credit: Mark Garlick/HELAS. Source:

In 7 billion years time, the Sun will run out of fuel. As it dies, it will swell so big that many predict that it will reach as far as Earth’s orbit. Naturally, the likelihood of the Earth still harbouring life may be debatable (after all 7 billion years is a long, long time), but should the human race still be around, and evolved into something totally unrecognizable, what will we see?
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The Chaotic Nature of Magnetic Reconnection and Coronal Dynamics

TRACE image of a hot coronal loop. Image credit: NASA

The solar corona is a strange place. For the last few decades solar physicists have been trying to understand why it is so hot. Yes, it’s the Sun, and yes, it’s hot, but the corona is too hot. There are many possible solutions to the “coronal heating phenomenon”, but physicists are generally in agreement that this extreme heating is down to waves propagating along magnetic fields, interacting with coronal plasma, or by reconnection events (small explosions). In a study published earlier this year, scientists suggest that to account for the temperatures and densities observed in the corona, chaotic forces may be at work, regulating the scales of reconnection in the coronal plasma.

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Hinode Discovers the Sun’s Hidden Sparkle

Hinode X-ray jet. Image credit: NASA

Blinking spots of intense light are being observed all over the lower atmosphere of the Sun. Not just in the active regions, but in polar regions, quiet regions, sunspots, coronal holes and loops. These small explosions fire elegant jets of hot solar matter into space, generating X-rays as they go. Although X-ray jets are known to have existed for many years, the Japanese Hinode observatory is seeing these small flares with unprecedented clarity, showing us that X-ray jets may yet hold the answers to some of the most puzzling questions about the Sun and its hot corona. [more]