Massive sun 'umbrella' attached to asteroid could help fight global warming, scientist says

[Judi Lynn]

By Rahul Rao published about 3 hours ago

A new study lays out the theoretical plan of tethering a giant solar shield to a captured space rock. Potentially, this contraption could protect Earth from the sun.



An illustration of a blue, triangular "umbrella" attached to an asteroid in space.
An artist's illustration of the theoretical sun "umbrella." (Image credit: Brooks Bays/UH Institute for Astronomy)


To help combat the effects of global warming, scientists are toying with an innovative idea to shield our planet from the sun with a spaceborne "umbrella" of sorts.

"In Hawaii, many use an umbrella to block the sunlight as they walk about during the day," István Szapudi, an astronomer at the University of Hawaii Institute of Astronomy, said in a statement. "I was thinking, could we do the same for Earth and thereby mitigate the impending catastrophe of climate change?"

The reason carbon dioxide and other greenhouse gases contribute to global warming is that they trap sunlight around our planet that should be released back into space, ultimately leading to rising temperatures. But it's the sun, and not greenhouse gases, that creates the heat to begin with. That opens up the idea of building Earth a shade.

So, Szapudi drew up an "umbrella" of his own. It would rest at the L1 Lagrange point between the sun and Earth, hypothetically joining sun- or solar-wind-observing probes such as the Solar and Heliospheric Observatory (SOHO) and Advanced Composition Explorer (ACE) that dwell there today. In theory, a large-enough solar shield could effectively block around 1.7 percent of solar radiation at L1, enough to prevent a catastrophic rise in Earth's temperatures.

More:
https://www.space.com/sun-umbrella-attached-to-asteroid-fight-global-warming