Washington Feb 16 (IANS) NASA s Hubble space telescope has captured Neptune s mysterious dark storm that probably smells like rotten eggs shrinking out of existence.
"It looks like we re capturing the demise of this dark vortex and it s different from what well-known studies led us to expect " said Michael Wong of the University of California at Berkeley in the US and co-author of a related paper published online in the Astronomical Journal.
Immense dark storms on Neptune were first discovered in the late 1980s by NASA s Voyager 2 spacecraft.
Since then only Hubble has had the sharpness in blue light to track these elusive features that have played a game of peek-a-boo over the years.
Hubble found two dark storms that appeared in the mid-1990s and then vanished. This latest storm was first seen in 2015 but is now shrinking NASA said on Thursday.
Like Jupiter s Great Red Spot the storm swirls in an anti-cyclonic direction and is dredging up material from deep inside the ice giant planet s atmosphere.
Scientists believe that dark spot material may be hydrogen sulfide with the pungent smell of rotten eggs.
"The particles themselves are still highly reflective; they are just slightly darker than the particles in the surrounding atmosphere " Joshua Tollefson from University of California at Berkeley explained.
Unlike Jupiter s Great Red Spot which has been visible for at least 200 years Neptune s dark vortices last only a few years.
"This is the first one that actually has been photographed as it is dying " NASA said.
--IANS
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