European dual satellite mission bids to create total solar eclipse on demand | space

European scientists are preparing to launch a space mission aimed at creating a total solar eclipse on demand.

The Proba-3 robotic spacecraft will be launched by the European Space Agency (ESA) in a few weeks on a mission that will involve flying a pair of satellites in close formation around Earth. They will be linked by lasers and light sensors, with one probe blocking the view of the Sun as seen from the other. The effect will be to create a solar eclipse that will last for several hours.

The European Space Agency says observing these eclipses will revolutionize the study of the Sun and the understanding of how it can cause outages in power lines, GPS satellites and other ground-based technology. The agency believes the mission will also serve as a path for other spaceflights that could transform studies of gravitational waves, exoplanets and black holes.

“It’s a very promising technology,” said solar physicist Francisco Diego of University College London. “It’s also very challenging technically. Getting it right won’t be easy, but it will be very rewarding.”

The mission, which took more than 10 years to plan, included developing a series of complex sensors that will keep the two satellites close to each other with sub-millimeter accuracy as they fly around the Earth at a distance of 144 metres. In fact, the two probes will act as one 144-meter-long observatory.

“When the two satellites are in exactly the right orbit, one of them will release a disk that will completely cover the Sun as seen from the second satellite, thus creating an eclipse that will last up to six hours a day,” Proba-3 project director Damien Galano told observer.

On Earth, a total solar eclipse occurs when the Moon passes in front of the Sun, blocking its stunning glow and leaving its fiery atmosphere – the corona – open for study by astronomers.

He added: “Unfortunately, total solar eclipses occur on average every two years or so on Earth, and scientists often have to travel long distances and be at the mercy of the weather to study them – while observations can only take a few minutes.” Diego. “This does not provide a lot of time to provide detailed feedback.” Likewise, devices called coronagraphs that simulate eclipses and are mounted on telescopes cannot observe the Sun’s inner corona in detail.

Scientists are particularly keen on studying the inner corona of the sun because of its temperature. The surface temperature of the Sun is about 6000 degrees Celsius, while the temperature of its corona is about one million degrees. “This is a paradox,” said Andrei Zhukov, the lead researcher on the corona experiment that will be carried on board Proba-3. “You would expect it to get colder the further away from the sun it is, but that is not the case.”

By allowing scientists to create a solar eclipse lasting hours, Proba-3 should generate the data that will solve this mystery. “We will be able to study the inner corona at length and in detail, and generate information explaining why it is so hot while the Sun’s surface underneath is relatively cool. This should give us an understanding of how the Sun affects space weather,” Diego added.

Zhukov supported this point, saying: “The Sun is the source of space weather disturbances, which can affect GPS navigation, energy transmission and other technologies. We have to understand how he does it.”

Improved understanding of the Sun’s corona will also be crucial for future space missions. Sometimes an event known as a coronal mass ejection occurs, when the Sun spits a huge plume of plasma into space. When this hits Earth’s upper atmosphere, it produces an aurora and can sometimes disrupt energy transfer.

“In general, we are protected by the atmosphere and the Van Allen radiation belts that surround the Earth,” Diego said. “However, in deep space there is no such protection from this radiation, and if we want to send men and women to the Moon and Mars, we want to be able to understand and predict how the sun’s corona will behave and thus prevent it from happening.” Our astronauts from getting hurt.

However, Proba-3 should do more than just revolutionize solar physics. As a technology leader in flying probes in formation, they could form the core of an entirely new approach to robotic spaceflight — using a few small satellites to mimic the operations of a single giant spacecraft, astronomers say.

“The technologies developed to power Proba-3 can be exploited for many other astronomical missions, including constellations of satellites that can study black holes, exoplanets, gravitational waves, and many other phenomena,” Galano added. “This whole approach to spaceflight holds a great deal of promise.”