But STEREO-A continued. And its orbit around the sun meant that it gave the spacecraft a chance to eventually return home, something few of her other NASA probes had been able to do. .
When that happened earlier this month, when STEREO-A passed between the Sun and Earth for the first time since its launch in 2006, NASA said: announced. The flyby was a milestone for the spacecraft and the team that has been monitoring its progress, and a chance for STEREO-A to prove its relevance almost 20 years later. While STEREO-A will continue to pass close to Earth, it will be used to conduct new research on the Sun, aided by new NASA satellites that have been developed since launch.
STEREO program scientist Rika Guhatakurta told The Washington Post, “This is the time when the mission can shine again.”
Two STEREO spacecraft are on an ambitious mission to generate a 360-degree view of the Sun by observing the stars from two vantage points while orbiting in opposite directions diverging from Earth. It was launched in October 2006. STEREO-A entered an orbit around the Sun ahead of Earth, and STEREO-B began orbiting the Sun behind Earth in the opposite direction.
Guhathakurta said the difference in perspective was groundbreaking. Earth-based instruments can only observe her one slice of the Sun facing the Earth at a time, leaving the rest of the rapidly changing Sun’s surface obscured. From an offset position, the twin STEREO spacecraft allowed scientists to: capture For the first time, I was able to see the sun in 360 degrees. Guhata Kurta is still in awe of this feat.
“Seeing the sun from the front and from the back at the same time is something special,” she said. “We humans are on Earth and we are achieving it.”
The STEREO craft has also enabled scientists to better study the rolling surface of the Sun and the dangers that erupt from it. The two spacecraft worked in the same way two eyes produce depth perception, providing her three-dimensional view of the sun and the sun. coronal mass ejection – Plumes of plasma and magnetic fields erupting outward from the Sun’s outer atmosphere at hundreds or thousands of miles per second, potentially threatening Earth’s power grids and satellites, as well as other planets and NASA spacecraft. there is. The images allowed scientists to track the shape, density, and speed of coronal mass ejections that ripple through the solar system.
While STEREO-A and STEREO-B continue their orbits, Approaching the It was a testament to how far they had traveled, but it was also a big risk. Moving directly behind the Sun would cut off communications between the rover and her NASA for months.
The two whimsical spacecraft were years past their expiration date and weren’t designed to operate without communication from NASA for that long. While conducting tests in preparation for downtime, the agency lost contact with STEREO-B. NASA briefly restored contact with the spacecraft in 2016, but Decided Authorities abandoned recovery efforts after a component failure caused uncontrolled rotation, making it impossible to orient the antenna and solar panels properly.
However, STEREO-A emerged from the far side of the Sun unharmed and began its long journey back to Earth. Earlier this month, the spacecraft passed between Earth and the Sun, coming within about five million miles of Earth. according to to NASA.
According to Guhathakurta, the spacecraft returned close to Earth at just the right time. When STEREO-A launched 17 years before him, it observed the Sun at the lowest point of its solar minimum, his 11-year cycle of high and low solar activity. This limited the number of coronal mass ejections and other phenomena that the spacecraft initially observed. This year, STEREO-A’s return coincided with a period of high solar activity.
And that flyby means I can finally get back to the work I used to do with my lost brother. A fleet of capable satellites and probes near Earth will help STEREO-A recreate the 3D image of the Sun that STEREO-B once captured, the agency said.
STEREO-A will continue research at the cutting edge of solar physics. Scientists hope to investigate recent phenomena using new data collected during the spacecraft’s flight. theory Coronal loops (giant arcs of solar material across the surface of the Sun when viewed in ultraviolet light) can be an optical illusion.
For Guhathakurta, who started working on the STEREO mission in 1998, STEREO-A’s tenacity after such a long journey is reassuring.
“It’s like watching kids grow up and do amazing things,” Guhatakuta said. She added that STEREO-A’s mission may not be completed, depending on NASA’s budget decisions. Either way, STEREO-A will continue its course towards another orbit around the Sun.
“They are not at home,” Guhatakuta adds with a laugh. “They will leave soon.”