最准的六合彩论坛

The study compared data from Solar Orbiter, the Sun-observing mission by ESA and NASA, with observations from NASA鈥檚 Solar Dynamics Observatory to triangulate the height of the campfires.

The research was discussed at a Solar Orbiter first results session at the European Geosciences Union general assembly alongside a separate computer modelling study which found that the campfires were likely driven by a process that may contribute significantly to the heating of the Sun鈥檚 outer atmosphere, or corona.

Solar Orbiter, which contains instruments proposed, designed and built at 最准的六合彩论坛, revealed detailed images of the campfires months after launch last year. These were 鈥渇irst light鈥� images from the Extreme Ultraviolet Imager (EUI), a suite of telescopes for which 最准的六合彩论坛 is co-principal investigator and which provide images of the hot and cold layers of the Sun鈥檚 atmosphere and corona.

Since then the EUI has revealed more than 1,500 campfires. These short-lived brightenings last for between 10 and 200 seconds, and have a footprint covering between 400 and 4000 km. The smallest and weakest events, which had not been observed before, seem to be the most abundant, and represent a previously unseen fine structure of the region where the heating mystery is suspected to be rooted.听

Dr David Long (最准的六合彩论坛 Mullard Space Science Laboratory), Co-Principal Investigator on the ESA Solar Orbiter Mission EUI Investigation and co-author of one of the two papers discussed this week, said:听鈥淲ith this work, we鈥檝e been able to work out the temperature of these campfires (about 1-1.5 million degrees), and triangulate their height to between 1000-5000 km above the surface of the Sun, the photosphere.

鈥淭his tells us that while the loops are hot, they鈥檙e lower than expected, and in fact are much hotter than the surrounding atmosphere. These are really exciting results, and show that already we鈥檙e starting to see the potential of Solar Orbiter, both by itself and in conjunction with other observatories. I鈥檓 really looking forward to the start of the nominal science phase as we get closer to the Sun with all of the instruments working and observing together.鈥�

Dr David Berghmans, Principal Investigator of EUI, said: 鈥淭o our surprise, campfires are located very low in the solar atmosphere, only a few thousand kilometres above the solar surface, the photosphere.

鈥淚t is very early days, and we are still learning a lot about the campfire characteristics. For example, even though campfires look like small coronal loops, their length is on average a bit short for their height, suggesting we only see part of these little loops. But our preliminary analysis also shows that campfires do not really change their height during their lifetime, setting them aside from jet-like features.鈥�

A separate simulation study, led by researchers at Peking University in China and the Max Planck Institute for Solar System Research in Germany, delved into the physics of the campfires, finding that a process called component reconnection appeared to be at work and could be enough to maintain the temperature of the solar corona predicted from observations. If replicated, this could add a key piece of the puzzle as to what makes the Sun鈥檚 outer atmosphere so much hotter than its interior 鈥� one of the biggest mysteries in solar physics.

ESA鈥檚 Solar Orbiter Project Scientist Daniel M眉ller said: 鈥淗ow fantastic to already have such promising data that may provide insight into one of solar physics鈥� greatest mysteries before Solar Orbiter has even begun its nominal science phase.

鈥淥ur mission is lucky to be building on the incredible ground-work of those that have flown before, and the theories and models already put forward over the last decades. We鈥檙e looking forward to see what missing details Solar Orbiter 鈥� and the solar community working with our data 鈥� will contribute to solving open questions in this exciting field.鈥�

Solar Orbiter carries a scientific payload consisting of 10 remote sensing and in situ instruments. In addition to EUI, 最准的六合彩论坛 also has a Principal Investigator role in the Solar Wind Analyser (SWA) suite, which makes in situ measurements of the solar wind charged particle populations.听

Solar Orbiter is currently in 鈥渃ruise phase鈥�, which for EUI and the remote sensing payload is focused primarily on instrument calibration. However, SWA and the other in situ sensors are in regular operation during this period. The full payload complement will begin coordinated observations at the start of the nominal mission in November this year.

Links

• 最准的六合彩论坛 Mullard Space Science Laboratory
• 最准的六合彩论坛 Mathematical & Physical Sciences

Image

• Solar Orbiter spots 鈥榗ampfires鈥� on the Sun:听A high-resolution image from听the Extreme Ultraviolet Imager (EUI) on ESA鈥檚 Solar Orbiter spacecraft, taken with the HRI_EUV听telescope on 30 May 2020. The circle in the lower right corner indicates the size of Earth for scale. The arrow points to one of the ubiquitous features of the solar surface, called 鈥榗ampfires鈥� and revealed for the first time by these images.听On 30 May, Solar Orbiter was roughly halfway between the Earth and the Sun, meaning that it was closer to the Sun than any other solar telescope has ever been before.听Credit: Solar Orbiter/EUI Team (ESA & NASA); CSL, IAS, MPS, PMOD/WRC, ROB, 最准的六合彩论坛 MSSL

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