Fiery rings of ionised gas erupt from the sun in the first videos taken by NASA鈥檚 Solar Dynamics Observatory. The satellite is delivering unprecedented views of the star, which could help untangle the mysteries of its magnetic field and improve forecasts of solar storms on Earth.
The observatory, which launched on 11 February, takes ultra-sharp images of the entire disc of the sun 鈥� previous high-resolution satellites could see only small portions of its surface at a time.
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鈥淚t is the most comprehensive view of the sun,鈥� Madhulika Guhathakurta, the mission鈥檚 programme scientist at NASA, said at a press briefing on Wednesday. 鈥淲hen you see the whole sun, it is showing connections we have never seen before.鈥�
One of the probe鈥檚 instruments, the Atmospheric Imaging Assembly (AIA), uses four telescopes to study the sun鈥檚 surface and atmosphere. It caught a giant gas loop called a prominence shooting out from the sun on 30 March (first part of video). Prominences are confined by the sun鈥檚 magnetic fields, whose origin and behaviour are not well understood.
Energy release
Several regions of intense magnetic fields were measured by another instrument, the Helioseismic and Magnetic Imager, on 8聽April (middle part of video). One of these regions erupted in a burst of energy called a solar flare (bright spot near the upper left portion of the sun).
A blast wave spread outward from the flare, heating and ejecting material from the sun鈥檚 outer atmosphere in an event called a coronal mass ejection (CME). If the Earth gets in the way of a CME, the particles can zap satellites, endanger astronauts and knock out power grids.
This CME did not cause damage but shot a significant amount of material towards Earth. 鈥淲hat we鈥檝e ejected here is an amount of mass about the same as contained in the whole Mississippi river, and we鈥檝e ejected it at a speed of about a million miles per hour鈥� in about 30 seconds,鈥� said Alan Title, the instrument鈥檚 principal investigator at the Lockheed Martin Solar and Astrophysics Laboratory in Palo Alto, California.
The AIA instrument studied the eruption at a range of wavelengths, which correspond to temperatures ranging from 80,000 掳C to 10 million 掳C (shown as different colours in the video). 鈥淎s the wave propagates across the sun, you can see the colours change, [which shows] how rapidly the gas is heating,鈥� Title said. 鈥淔rom this, we can begin for the first time to decode how this energy is released into the outer atmosphere, and鈥� how it impacts us.鈥�
The $808 million observatory will operate for at least five years.
