solar orbiterthe joint mission of the European Space Agency (ESA) and NASA, provided the images that the spacecraft took when on March 7 it was at a distance of about 75 million kilometers, halfway between our planet and its mother star.
One of the photographs, taken by the instrument Extreme Ultraviolet Imager (EUIoperating in the extreme ultraviolet region of the electromagnetic spectrum) is the highest resolution image obtained of the entire disk of the Sun and its outer atmosphere, the corona, which has a temperature of about one million degrees Celsius.
The EUI High Resolution Telescope captures images of such high spatial resolution that, at such close distance, a mosaic of 25 images To cover all the sun. Taken one after the other, the entire image was captured over the course of four hours, as each mosaic takes about 10 minutes, including the time it takes the spacecraft to point from one segment to the next.
In total, the final photograph contains more than 83 million pixels in a 9148 x 9112 pixel grid. For comparison, it has ten times better resolution than a 4K TV screen can display. On the ESA website can be enlarged on it to see all the details.
At the 2 o’clock position (near the small Earth image in the background) and 8 o’clock at the edges of the Sun, dark filaments can be seen protruding from the surface. These ‘prominences’ are prone to eruptions, spewing huge amounts of coronal gas into space and creating solar stormsimportant in studies of space weather.
Full image of the Sun captured by Solar Orbiter. / ESA & NASA/Solar Orbiter Team/EUI; Data Processing: E. Kraaikamp (ROB)
Another image, taken by the instrument Spectral Image of the Coronal Environment (SPICE)also represents the first complete view of the Sun in 50 years, and by far the best, taken at the so-called wavelength lyman-beta of the ultraviolet light emitted by the hydrogen gas.
SPICE recorded the data during the trip and also had to collect it in mosaic form. It is designed to trace the layers of the sun’s atmosphere from the corona to a layer known as the chromosphere, enlarging the surface. The instrument does this by observing the different wavelengths of the extreme ultraviolet light that come from different atoms.
In the sequence of images provided by SPICE, purple corresponds to hydrogen gas at a temperature of 10,000 °C, blue to carbon at 32,000 °C, green to oxygen at 320,000 °C and yellow to neon at 32,000 °C. 630,000°C.
Images of the Sun taken by the SPICE instrument at various wavelengths of the extreme ultraviolet spectrum, associated with different layers of the lower solar atmosphere. The purple color corresponds to hydrogen gas at a temperature of 10,000°C, blue to carbon at 32,000°C, green to oxygen at 320,000°C and yellow to neon at 630,000°C. / ESA & NASA/Solar Orbiter Team/SPICE; Data processing: G. Pelouze (IAS).
This data will allow solar physicists to study the extraordinarily powerful outbursts that occur in the corona through the lower atmospheric layers, as well as investigate one of the most intriguing observations about the Sun: how temperature rises through the ascending atmospheric layers.
Investigate strange temperature differences
Normally, the temperature drops as we move away from a hot object. But above the Sun, the corona reaches a million degrees Celsius, while the surface is only around 5,000°C. Investigating this mystery is one of Solar Orbiter’s main scientific goals.
As the images were only taken on March 7, precisely when the Solar Orbiter crossed the Sun-Earth line, they can be compared to those captured by solar instruments on Earth. This will make it easier to compare results from different instruments and observatories in the future.
O March 26thSolar Orbiter will reach another mission milestone: its first perihelion or closest point to the Sun. The spacecraft is now within Mercury’s orbit taking the highest resolution images of our star that it has been able to capture so far. It is also recording data on the solar wind from particles flowing from the Sun.
And this is just the beginning, in the next few years the spacecraft will repeatedly fly on its approaches to our star and also gradually increase its orientation to observe the unexplored solar polar regions.