Solar Orbiter, ESA’s solar probe, has just captured superb images, the most precise of the Sun to date.
Although it is certainly the most famous for having recently “touched” the Sun (see our article), the Parker Solar Probe is not the only probe to be interested in our star. Solar Orbiter, the probe of the European Space Agency, also keeps its eyes riveted on the star; he has just given us some magnificent shots of the Sun, the most detailed to have been captured to date.
This series of photos was taken on March 7, when Solar Orbiter was right halfway between Earth and its star, about 75 million kilometers from the two celestial bodies. At this moment, the probe had a remarkable view of the star; ESA astronomers therefore took the opportunity to draw his portrait using an instrument called the Extreme Ultraviolet Imager.
It is an instrument that observes at a wavelength of 17 nanometers, ie in the extreme ultraviolet range, at the very end of the electromagnetic spectrum. This is a very interesting field of observation in the context of the Sun, because it allows you to observe both the atmosphere, the corona, and their convolutions with a stunning level of detail.
A mosaic of impressive precision
But they couldn’t do it in one picture. Because if these 75 million kilometers represent a considerable distance on a human scale, it remains very close for instruments of this type; they are indeed calibrated to capture a very small portion of the sky at a time. The machine therefore had to start over several times; it took him no less than 25 different shots to capture each portion, which took over 4 hours in total.
These shots were then synthesized into a single image in very high resolution; the end result features 83 million pixels (9148 x 9112), ten times the maximum resolution of a modern 4K TV. Until then, no instrument had managed to capture a complete image of the Sun with this exceptional level of detail.
Indeed, this is the very first time that a probe equipped with a camera pointed directly at the star has come so close. Other machines, starting with the Parker Solar Probe which “touched” the Sun recently, approach it much closer. On the other hand, the latter is quite unable to take this type of photography; at the distance it operates, any camera turned in that direction would be instantly reduced to dust.
The best is yet to come
In its statement, the agency hosted the very high quality version of this image. It is possible to zoom in to observe the beautiful swirls of the solar atmosphere in stunning detail. And the icing on the cake is that this is probably just the beginning.
Indeed, Solar Orbiter will continue to approach the Sun. It will initially move away from it before returning its orbit to approximately 42 million kilometers; it’s about twice as close as the point where these photos were taken. Inevitably, this will represent a new opportunity to once again draw the portrait to the star; in a few months, even more detailed images to be obtained.
For the anecdote, Solar orbiter also takes advantage of its journey to collect data on the solar winds. This is supersonic plasma flow theorized by the late Eugene Parker; this eminent scientist, true “Sun-King” of modern astrophysics, passed away on March 15 (see our article)
Solar Orbiter will therefore continue to honor his memory and deepen its work of colossal scientific significance until 2027; he will then meet a disastrous end which will precipitate him either straight into the Sun, towards the surface of Venus, or light years from the solar system. But in the meantime, he will undoubtedly have contributed to superb discoveries on Dr. Parker’s favorite star.