On Thursday, UFO-hunter Pamela Johnson posted to Facebook that she had discovered something extraordinary. While mining through the images taken by NASA’s STEREO spacecraft, she came across a “huge object,” writing that NASA previously “has tried to use EUVI 171 images of the sun to hide the sphere.” Turns out that “huge object” is already pretty familiar, though.
By Saturday, the images had gone viral with internet commenters spitballing that it could be anything from aliens to a rogue planet.
Of course, a little fact-checking found that this “huge spherical object” is, indeed, a huge spherical object. But it is not an alien mothership — it’s the sun.
Because of a glitch, two sets of data became superimposed into a single image — the one Johnson happened to look at. This glitch happens when the image processor on STEREO gets overloaded.
“The data comes down in a big stream, and we process that data, we pluck the images out as they’re coming down,” Alex Young of NASA’s Goddard Space Flight Center told Popular Mechanics. “Sometimes the stream [can] get corrupted. That causes the computer program that processes those images to get them wrong.”
Not an alien.
Disappointed alien-hunters can be comforted by the fact that this glitch happened because of some very cool science. STEREO is a NASA spacecraft that made up of two spaced-based observatories. It stands for the Solar TErrestrial RElations Observatory, and one of its observatories traces Earth ahead of its orbit and the other trails behind. This allows NASA to have two viewpoints in which to watch the evolution of the sun’s solar storms.
The image in question here was taken with an instrument on STEREO called SECCHI — a suite of five scientific telescopes that take images of the sun and the spaces between the sun and Earth. Then the data is sent back to Earth where, as we’ve learned from this commotion, sometimes data images can accidentally get combined. The big ball of the sun became superimposed on the images of Earth and Venus.
STEREO has been doing its business for ten years, providing data that allows scientists to determine the structure of solar wine and discover the mechanisms and sites of solar energetic particle acceleration. It’s important that STEREO is up there so that NASA can study coronal mass ejections — giant clouds of solar plasma that can trigger severe magnetic storms. These storms pose a major threat to satellites and to astronauts who are outside of the protection of a space shuttle.
So what STEREO is actually doing is a lot cooler than fake news about aliens. The very human problem, however, is sharing about aliens instead of the good work being done by other humans.
