​New York, March 3 (IANS) NASA scientists have demonstrated that a new space weather warning system could help astronomers detect harmful solar particles much before they leave the sun's inner atmosphere -- critical extra time that could help protect astronauts in space.

Solar energy particles (SEPs) can move at nearly the speed of light -- so their total travel time can be less than an hour from the time they are accelerated near the sun to when they reach Earth.

In the study published in the journal Space Weather, scientists from NASA and the US National Center for Atmospheric Research, or NCAR, in Boulder, Colorado, showed how ground-based instruments called coronagraphs can help lengthen the warning time for solar particles.

Earth's magnetic field and atmosphere protect us on the ground from most of the harmful effects of space weather, but astronauts in low-Earth orbit -- or even, one day, in interplanetary space -- are more exposed to space weather, including bursts of fast-moving particles called solar energetic particles, or SEPs.

"Robotic spacecraft are usually radiation-hardened to protect against these kinds of events," said lead author on the study Chris St. Cyr, a space scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. 

"But humans are still susceptible," Cyr said.

So NASA wants to help improve systems that would provide future astronauts with advance warning of incoming SEPs. 

In the recent paper, the scientists showed that tracking an associated kind of solar explosion -- fast-moving clouds of magnetic solar material, called coronal mass ejections -- can help.

Scientists observe coronal mass ejections using a type of instrument called a coronagraph, in which a solid disk blocks the sun's bright face, revealing the sun's tenuous atmosphere, called the corona. 

Space-based coronagraphs are more widely used in space weather research because of their wide-field solar views that are not interrupted by cloud cover or Earth's rotation. 

But the new study showed that ground-based coronagraphs could improve the warning system.