Tales of the Solar Wind Sherpas
Every 12 to 18 months, the Sherpas get ready for an expedition to different corners of the Earth, with backpacks loaded with cameras, special filters and spectrometers. They await the arrival of a new Moon, and its perfect alignment between the Sun and the Earth that will block the bright disk of the Sun. As the Sun suddenly finds itself getting obscured, a feeling of suspense and awe, sometimes fear, electrifies the air. A shadow a hundred miles wide darkens the Earth in mid-day. An hour later, the darkness is total. The temperature drops by a few degrees. Not a sound can be heard, not a bird sings.
If lucky, the Sherpas will have clear skies to witness a cosmic spectacle beyond compare, when a diamond ring suddenly glitters in the darkened sky followed by whispy shimmering filaments, exploding outwards from the edges of the Sun into the infinity of space, while red flames (known as prominences), anchored to the Sun, sway erratically.
—A page containing background information for each member of the Solar Wind Sherpas
—A page containing the history of the Solar Wind Sherpas as recounted by our leader, Shadia Habbal
—Stories and anecdotes by members of the Solar Wind Sherpas
The Sherpas are out to explore the invisible colors of the corona. With their cameras retrofitted with special filters, and their own spectrometer design, they will peer into the behavior and fate of the heavy elements that have lost most of their electrons and emit light at very specific colors. The most dominant elements are hydrogen, helium, iron, nickel, oxygen, carbon and calcium, to name a few. Each one of them holds a secret to the hot corona that escapes the Sun forming its own solar wind. The cool prominences at tens of thousands of degrees seem to be oblivious to the million degrees corona around them. How do they shield themselves from this scalding environment is another mystery. Their erratic dances seem to have a hold on the dynamic nature of the coronal structures controlled by the magnets produced in the Sun’s interior layers. Their dance occasionally goes wild leading to their eruption and the ejection of huge bubbles, known as coronal mass ejections, into the solar system. When they hit Earth, we are in trouble.
On 21 August 2017, in a span of 90 minutes the Moon’s shadow will fall upon Oregon and spread to South Carolina. With a couple of minutes at each step along the way, millions can witness the clockwork of planetary motion that will reveal the beauty of their own star. That evening at dusk, a sliver from the new Moon will smile mischievously, proud to have put on a magnificent show. It will linger asking for attention and thankfulness. In the day after, all will be forgotten, but not for the Moon who knows that it can repeat its trick, even if it has to take it a little over a year. Fully aware of its trick, the Sherpas will get ready for another expedition.
—Shadia Habbal, 2017