Icarus Takes Flight

Discoveries Icarus Takes Flight The European Space Agency (ESA) is preparing to make history by creating an artificial solar eclipse in space. Next week, the Proba-3 mission will launch two satellites that will block the Sun’s light and capture unprecedented images of its faint outer atmosphere, or corona. “This ambitious ESA mission has been many years in the making because it is seeking to do something in space that has previously been impossible,” said Damien Galano, Proba-3 mission manager, in a statement. Proba-3 will launch aboard an Indian PSLV-XL rocket, marking ESA’s first mission launched from India since 2001. The two spacecraft will enter a highly elliptical orbit, traveling between 373 miles and more than 37,000 miles from Earth. The occulter spacecraft – carrying a 4.6-foot-wide disk – will align precisely with the Sun to block its light. Meanwhile, the coronagraph spacecraft that is positioned 492 feet behind will capture images of the Sun’s corona. “It will be the closest to the Sun we have observed the corona in visible light,” Galano separately told New Scientist this month. Scientists hope that studying the corona will help answer key questions about its temperature, how it expands into space, and the origins of solar wind. The mission may also help predict solar weather, such as geomagnetic storms that can disrupt satellites, communication networks, and power grids on Earth. Meanwhile, the task will require a lot of precision: The spacecraft must maintain their positions to within 0.04 inches. This is made possible by advanced sensors and 12 nitrogen thrusters on the occulter, capable of adjustments as subtle as 0.002 pounds of force. Each artificial eclipse will last up to six hours, with more than 1,000 eclipses planned over the two-year mission. These will occur at the spacecraft’s highest orbital point to reduce Earth’s gravitational interference and minimize the satellites’ fuel consumption. ESA researchers hope that the Proba-3’s flying techniques could revolutionize spacecraft refueling techniques, in-orbit assembly of large telescopes, and space weather modeling. “Up until now, we’ve only been able to do a centimeter precision or more,” Steve Buckley, lead engineer for Proba-3 noted to New Scientist. “This is 10 times better.”