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STS-120 day 2 highlights

Flight Day 2 of Discovery's mission focused on heat shield inspections. This movie shows the day's highlights.

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STS-120 day 1 highlights

The highlights from shuttle Discovery's launch day are packaged into this movie.

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STS-118: Highlights

The STS-118 crew, including Barbara Morgan, narrates its mission highlights film and answers questions in this post-flight presentation.

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 Mission film

STS-120: Rollout to pad

Space shuttle Discovery rolls out of the Vehicle Assembly Building and travels to launch pad 39A for its STS-120 mission.

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Dawn leaves Earth

NASA's Dawn space probe launches aboard a Delta 2-Heavy rocket from Cape Canaveral to explore two worlds in the asteroid belt.

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Dawn: Launch preview

These briefings preview the launch and science objectives of NASA's Dawn asteroid orbiter.

 Launch | Science

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Solar flare from a blank Sun
BY DR EMILY BALDWIN
ASTRONOMY NOW

Posted: April 28, 2008

Despite the currently blank face of the Sun, it still has enough energy to surprise us with a solar flare, an event that is normally associated with the presence of a sun spot.

At 1408 on 26 April, Earth-orbiting satellites detected a surge of X-rays registering B3.8 on the Richter scale of solar flares, a relatively weak event, originating from a patch of the Sun where magnetic fields were not intense enough to form a visible sunspot. However, the magnetic fields still had sufficient energy and instability to cause a powerful solar tsunami spreading through the Sun’s atmosphere and out into space as a coronal mass ejection (CME).

The expanding CME could deliver a punch to the Earth’s magnetic field in the next couple of days, triggering bursts of auroral activity in the high latitudes.

Latest images from SOHO. The image on the left shows the blank face of the Sun and the image on the right shows the current state of the magnetic field in the solar photosphere, with black and white indicating opposite polarities. Image: SOHO/MDI.