<pedrocorreia.net ⁄>
 

<Solar Dynamics Observatory: The Variable Sun Mission ⁄ >




clicks: 4438 4438 2010-02-06 2010-02-06 goto ciencia myNews ciencia  Bookmark This Bookmark This


For some years now, an unorthodox idea has been gaining favor among astronomers. It contradicts old teachings and unsettles thoughtful observers, especially climatologists.

"The sun," explains Lika Guhathakurta of NASA headquarters in Washington DC, "is a variable star."

But it looks so constant...

That's only a limitation of the human eye. Modern telescopes and spacecraft have penetrated the sun's blinding glare and found a maelstrom of unpredictable turmoil. Solar flares explode with the power of a billion atomic bombs. Clouds of magnetized gas (CMEs) big enough to swallow planets break away from the stellar surface. Holes in the sun's atmosphere spew million mile-per-hour gusts of solar wind.

And those are the things that can happen in just one day.

Over longer periods of decades to centuries, solar activity waxes and wanes with a complex rhythm that researchers are still sorting out. The most famous "beat" is the 11-year sunspot cycle, described in many texts as a regular, clockwork process. In fact, it seems to have a mind of its own.



este é só um excerto do artigo, para aceder ao artigo completo, clique no link em baixo:
this is just a small excerpt from the article, to access the full article please click in the link below:

http://science.nasa.gov/headlines/y2010/05feb_sdo.htm




Subscribe News RSS  Subscribe News Updates by E-mail





myNews <myNews show="rand" cat="ciencia" ⁄>

NASA Unveils Their New Launch System

NASA Adminstrator Charlie Bolden and several members of Congress announced today the decision on NAS (...)

clicks: 5381 5381 2011-09-21 2011-09-21 goto url (new window) universetoday.c... goto myNews ciencia


Breakthrough Study Confirms Cause of Short Gamma-Ray Bursts

A new supercomputer simulation shows the collision of two neutron stars can naturally produce the ma (...)

clicks: 5484 5484 2011-04-18 2011-04-18 goto url (new window) nasa.gov/topics... goto myNews ciencia


NASA's Kepler Mission Helps Reveal the Inner Secrets of Giant Stars for the First Time

University of Sydney astrophysicists are behind a major breakthrough in the study of the senior citi (...)

clicks: 5389 5389 2011-04-09 2011-04-09 goto url (new window) nasa.gov/missio... goto myNews ciencia


Best Images from 2010

Here are some of the best space and astronomy images from 2010. These are in no particular order or (...)

clicks: 7062 7062 2011-01-01 2011-01-01 goto url (new window) universetoday.c... goto myNews ciencia


Voyager 1 Has Outdistanced the Solar Wind

The venerable Voyager spacecraft are truly going where no one has gone before. Voyager 1 has now rea (...)

clicks: 5751 5751 2010-12-25 2010-12-25 goto url (new window) universetoday.c... goto myNews ciencia


Food expiration dates: What do they really mean?

Are you one of those people who pour the milk down the drain on the expiration date? Expiration d (...)

clicks: 5706 5706 2010-09-16 2010-09-16 goto url (new window) green.yahoo.com... goto myNews ciencia


NASA - A Galactic Spectacle

A beautiful new image of two colliding galaxies has been released by NASA's Great Observatories. The (...)

clicks: 5755 5755 2010-08-21 2010-08-21 goto url (new window) nasa.gov/missio... goto myNews ciencia


Calculate distance, bearing and more between Latitude/Longitude points

(...)

clicks: 7043 7043 2010-08-12 2010-08-12 goto url (new window) movable-type.co... goto myNews ciencia