High-Resolution Images of the Sun Show How Flares Impact the Solar Atmosphere

A solar flare erupts on the Sun. Credit: NASA/GSFC/SDO

Solar flares are a fascinating thing and have a profound effect on what astronomers refer to as “space weather.” These events vary with the Sun’s 11-year solar cycle, releasing immense amounts of radiation across the electromagnetic spectrum (from extreme ultraviolet to X-rays) into space. The effects of flares have been observed since time immemorial, which include aurorae at high latitudes (Aurora Borealis and Australis), but have only been the subject of study and prediction for about a century and a half. Still, there is much that remains unknown about these dramatic events.

For instance, flares are known to affect the Sun’s atmosphere, from the visible surface (photosphere) to its outermost layer (corona). However, there are still questions about how these events influence the lower layers of the atmosphere. In a recent study led by the University of Colorado, Boulder, a team of researchers documented the rotation of two very small sunspots of the Sun’s surface (pores) using the Daniel K. Inouye Solar Telescope (DKIST) at Mauna Kea. These pores were linked to a less powerful flare and moved in a way that has never been observed, suggesting that the dynamics of the Sun’s atmosphere are more complex than previously thought.

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Kepler Sketched the Sun in 1607. Astronomers Pinpointed the Solar Cycle

The earliest datable sunspot drawings based on Johannes Kepler's solar observations with camera obscura in May 1607.

Johannes Kepler is probably most well known for developing the laws of planetary motion. He was also a keen solar observer and in 1607 made some wonderful observations of our nearest star using a camera obscura. His drawings were wonderfully precise and enabled astronomers to pinpoint where the Sun was in its 11-year cycle. Having taken into account Kepler’s location and the location of sunspots, a team of researchers have identified the Sun was nearing the end of solar cycle-13.

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Thierry Legault’s Stunning Views of the Space Station (with spacewalking astronauts) Crossing in Front of Sunspots

The International Space Station transiting the Sun -- and two large sunspots --on June 9, 2023. Additionally, two astronauts, Steve Bowen and Woody Hoburg were outside the ISS on a spacewalk while this image was taken. Credit and copyright: Thierry Legault.

He’s done it again, outdoing even his own incredible work.

Over the years, we’ve written many articles to share the beautiful and mind-bending astrophotography of Thierry Legault. Each year he seems to come up with ideas to try to surpass even his own craziest attempts of astrophotography feats – such as capturing spy satellites in orbit, or snapping pictures of the International Space Station (ISS) transiting the Sun during a solar eclipse.

Now, he was able to take pictures of the ISS transiting the Sun while two astronauts were doing a spacewalk. As an added challenge, Legault made sure he was in the right place at the right time so he could capture the ISS (and astronauts) while they were passing by three enormous sunspots.

WHAT??

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New Detailed Images of the Sun from the World’s Most Powerful Ground-Based Solar Telescope

A collage of new solar images captured by the Inouye Solar Telescope, which is a small amount of solar data obtained during the Inouye’s first year of operations throughout its commissioning phase. Images include sunspots and quiet regions of the Sun, known as convection cells. (Credit: NSF/AURA/NSO)

Our Sun continues to demonstrate its awesome power in a breathtaking collection of recent images taken by the U.S. National Science Foundation’s (NSF’s) Daniel Inouye Solar Telescope, aka Inouye Solar Telescope, which is the world’s largest and most powerful ground-based solar telescope. These images, taken by one of Inouye’s first-generation instruments, the Visible-Broadband Imager (VBI), show our Sun in incredible, up-close detail.

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The Sun Didn't Have any Sunspots for 70 Years, now we Might Know why

The Sun as seen over the years. Credit: NASA

Sunspots are one of the ways we can measure the activity level of the Sun. Generally, the more sunspots we observe, the more active the Sun is. We’ve been tracking sunspots since the early 1600s, and we’ve long known that solar activity has an 11-year cycle of high and low activity. It’s an incredibly regular cycle. But from 1645 to 1715 that cycle was broken. During this time the Sun entered an extremely quiet period that has come to be known as the Maunder Minimum. In the deepest period of the minimum, only 50 sunspots were observed, when typically there would be tens of thousands. We’ve never observed such a long period of quiet since, and we have no idea why it occurred.

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Astronomers Confirm the Existence of Magnetic Waves in the Sun’s Photosphere

Sunspots and a detached prominence photographed on July 11, 2014. (© Alan Friedman, All Rights Reserved.)

For the first time astronomers have observed waves of magnetic energy, known as Alfvén waves, in the photosphere of the sun. This discovery may help explain why the solar corona is so much hotter than the surface.

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Tree Rings Reveal 1,000 Years of Solar Activity

Solar activity over the last 1000 years (blue, with error interval in white), sunspot records (red curve) going back less than 400 years. The background shows a typical eleven-?year cycle of the sun. CREDIT ETH Zürich

The Sun has a lot of rhythm and goes through different cycles of activity. The most well-known cycle might be the Schwabe cycle, which has an 11-year cadence. But what about cycles with much longer time scales? How can scientists understand them?

As it turns out, the Sun has left some hidden clues in tree rings.

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Solar astronomers can now predict future sunspots. There should be a big one in a couple of days

Sunspot image from the newly upgraded GREGOR Telescope

The surface of the Sun is a turbulent dance of gravity, plasma, and magnetic fields. Much like the weather on Earth, its behavior can seem unpredictable, but there are patterns to be found when you look closely.

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What’s Happening with Betelgeuse? Astronomers Propose a Specialized Telescope to Watch the Star Every Night

Artist's impression of Betelgeuse. Credit: ESO/L. Calçada

Starting in late 2019, Betelgeuse began drawing a lot of attention after it mysteriously started dimming, only to brighten again a few months later. For a variable star like Betelgeuse, periodic dimming and brightening are normal, but the extent of its fluctuation led to all sorts of theories as to what might be causing it. Similar to Tabby’s Star in 2015, astronomers offered up the usual suspects (minus the alien megastructure theory!)

Whereas some thought that the dimming was a prelude to the star becoming a Type II supernova, others suggested that dust clouds, enormous sunspots, or ejected clouds of gas were the culprit. In any case, the “Great Dimming of Betelgeuse” has motivated an international team of astronomers to propose that a “Betelgeuse Scope” be created that cant monitor the star constantly.

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Solar Cycle 25 has arrived. Here’s what to expect from the Sun in the coming months and years

The sun goes through a regular 11-year cycle, swinging between periods of dormancy and periods of activity. Scientists from NASA and NOAA have just announced that the sun has just passed its minimum, and will be ramping up in activity over the next few years, meaning that we have entered a new round of the never-ending solar cycle.

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