HUMONGOUS ERUPTION & WATER on the Sun HD

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A truly gigantic explosion happened on the sun yesterday. On Nov. 16th, magnetic fields snaking halfway across the sun's southern hemisphere erupted in tandem, producing a prominence so big, it doesn't fit inside this image from NASA's Solar Dynamics Observatory (SDO):
The blast hurled a CME into space, but the cloud does not appear to be heading for Earth.
Analysis of sunlight, which started the discipline of spectroscopy, has been the key to a
number of major scienti® c discoveries. Sunspots, which are much cooler than most of the
Sun's surface, have particularly rich and complicated spectra which has long been thought to
be due to very hot water. The challenge of analysing this spectrum has stimulated the
development of new theoretical procedures based on full quantum mechanical treatments of
the vibrational and rotational motion of the water molecule. The result has been the
identi® cation of novel spectral features and a deeper understanding of how excited molecules
such as superheated water behave. This work has applications ranging from the models of
cool star atmospheres and rocket exhausts to the possible automated detection of forest
® res. Perhaps the most interesting result is the insight given to understanding how our own
atmosphere absorbs sunlight, and the possible consequences that this may have for modelling
the greenhouse effect.
JONATHAN TENNYSON and OLEG L. POLYANSKY
A movie, prepared by Steele Hill of the Goddard Space Flight Center, shows magnetic fields in concerted motion across an expanse of solar "terrain" more than 700,000 km wide. Observations by SDO have shown that such wide-ranging eruptions are not uncommon on the sun--the great Global Eruption of August 2010 being the iconic example.