Two weeks in the life of a sunspot

Public
Release:
4-Aug-2017
From Eurekalert               

NASA/Goddard Space Flight Center

On July 5, 2017, NASA’s Solar Dynamics Observatory
watched an active region — an area of intense and complex magnetic fields —
rotate into view on the Sun. The satellite continued to track the region as it
grew and eventually rotated across the Sun and out of view on July 17.

With their complex magnetic fields, sunspots are often
the source of interesting solar activity:

During its 13-day trip across the face of the Sun, the
active region — dubbed AR12665 — put on a show for NASA’s Sun-watching
satellites, producing several solar flares, a coronal mass ejection and a solar
energetic particle event. Watch the video below to learn how NASA’s satellites
tracked the sunspot over the course of these two weeks.

Such sunspots are a common occurrence on the Sun, but
less frequent at the moment, as the Sun is moving steadily toward a period of
lower solar activity called solar minimum — a regular occurrence during its
approximately 11-year cycle. Scientists track such spots because they can help
provide information about the Sun’s inner workings. Space weather centers, such
as NOAA’s Space Weather Prediction Center, also monitor these spots to provide
advance warning, if needed, of the radiation bursts being sent toward Earth,
which can impact our satellites and radio communications.

On July 9, a medium-sized flare burst from the sunspot,
peaking at 11:18 a.m. EDT. Solar flares are explosions on the Sun that send
energy, light and high-speed particles out into space — much like how
earthquakes have a Richter scale to describe their strength, solar flares are
also categorized according to their intensity. This flare was categorized as an
M1. M-class flares are a tenth the size of the most intense flares, the X-class
flares. The number provides more information about its strength: An M2 is twice
as intense as an M1, an M3 is three times as intense and so on.

Days later, on July 14, a second medium-sized, M2 flare
erupted from the Sun. The second flare was long-lived, peaking at 10:09 a.m. EDT
and lasting over two hours.

This was accompanied by another kind of solar explosion
called a coronal mass ejection, or CME. Solar flares are often associated with
CMEs — giant clouds of solar material and energy. NASA’s Solar and Heliospheric
Observatory, or SOHO, saw the CME at 9:36 a.m. EDT leaving the Sun at speeds of
620 miles per second and eventually slowing to 466 miles per second.

Following the CME, the turbulent active region also
emitted a flurry of high-speed protons, known as a solar energetic particle
event, at 12:45 p.m. EDT.

Research scientists at the Community Coordinated
Modeling Center — located at NASA’s Goddard Space Flight Center in Greenbelt,
Maryland — used these spacecraft observations as input for their simulations of
space weather throughout the solar system. Using a model called ENLIL, they are
able to map out and predict whether the solar storm will impact our instruments
and spacecraft, and send alerts to NASA mission operators if
necessary.

By the time the CME made contact with Earth’s magnetic
field on July 16, the sunspot’s journey across the Sun was almost complete. As
for the solar storm, it took this massive cloud of solar material two days to
travel 93 million miles to Earth, where it caused charged particles to stream
down Earth’s magnetic poles, sparking enhanced aurora.

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accuracy of news releases posted to EurekAlert! by contributing institutions or
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42 thoughts on “Two weeks in the life of a sunspot

  1. I remember when I was 8 and studying this, in primary school, in the UK. I was also pulled up in front of class by class teacher, Mr. Harris, for doodling during end of class story telling. I was doodling a solar flare and had to explain what the doodle was. Mr.Harris, for all he was good at, had no idea what the doodle was.

    • Hated to see Obama hang USMC Major General Charles Bolden (ret), a Marine fighter pilot & combat veteran, out to dry with that dumb mission statement.

      Bolden bore some of the blame for letting himself get used like that, but he gets a lot of forgiveness.

  2. I remember when I was a kid being pulled out of bed by my dad so I could see the aurora happening outside. What was unusual was that it was the middle of July and even though we were at the 44th parallel the aurora it was right overhead. It was astonishing.

    My dad told me to remember the event because I would likely never see it again in my lifetime. It’s been 50 years now and so far he’s right.

    • That’s great. Thanks for sharing it with us. I have never seen an Aurora, but I have seen a total eclipse of the Sun as will many very fortunate Americans on the 21st.

    • I was on the roof of Rochdale College on that night, watching the cartoon version of Animal Farm under the sky. It was an amazing night and I have not seen one like it since.

      Comparable for spectacle, however, is a cold summer night in Mongolia. The air is so clear that one can see 100 times more stars than can be imagined. Absolutely beautiful.

    • I was witness to an aurora borealis event only one time.

      I was a member of a “big game” hunting party in the northern British Columbia “bush” and awoke one early morning about 3 AM with a dire urge to go “wee wee”. So I stepped out of the tent-frame, still half asleep, and while relieving myself I glanced up in the clear night sky ……. and temporarily got the bejesus scared out of myself.

      Those eerily green n’ blueish lights were prancing and dancing all over the sky above me and moving so damn quick I just knew it was my imagination “playing tricks” on my good senses.

      It must have taken me 15 seconds before I became wide awake and realized what I was seeing, which was then that I exclaimed, …… “Holy Cow, those are the honest to goodness Northern Lights that I have been reading about and studying for all these past years”.

      A truly amazing sight when you witness them the 1st time.

      • Living in Southern Canada in a rural area I have seen them dozens of times. It never gets old. Light pollution obscures them for many millions unfortunately.

      • Samuel,
        I saw one stunning display in October 1972.
        We had berthed in Svolvaer. I walked a local young lady home.
        Just before her house, we stopped. and then the Aurora started.
        I can’t now remember how long – but possibly ‘half an hour’ [IIRC].
        At the conclusion she said it was the finest display she had ever seen, kissed me quickly, then went in.
        I made my solo way back to my ship – ‘British Cormorant’, Master Jimmy Gillan – and wrote to the young lady for a year or more.

        Ahhh. Young Lust!

        Auto

    • Klem,

      I am also on the 44th parallel and recall a very bright aurora about 16 or 17 years ago but it was not overhead, probably 25 to 30 degrees above the northern horizon. Unfortunately, I did not record the date though it was in the fall as we were returning from one of our boys’ football games on a long drive north headed home between 11 pm and 12 am. A memorable sight!

    • What was unusual about its occurring in the middle of July? Aren’t there equal chances of aurorae in all parts of the year? Sure, nighttime is shorter in summer, but during any given nighttime hours, the chances should be equal all year long.

    • A night to remember that happen for me was in July of 2014. When northern England was treated to a display of night shinning cloud that was a match for any Aurora display. lt was 3am in the morning and l was working a nightshift. The display covered about a quarter of the northern sky with swirls and twirls of bright sliver blue clouds. While lower down in the sky where the cloud became thicker and was in layers it then became white and then in places turning to yellow and red. Never seen anything like it in my life.

  3. As an Air Force Navigator, I have 50 missions over the North Pole. One mission there was Saint Elmo fire dancing on our wings and a plasma ball formed in the cockpit and then rolled down the walk way into the wing root. We did not detect and instrument problems. That was seeing the aruora up close and personal.

    • Flying a P-3 through a thunderstorm at night, we’d get a lot of St. Elmo’s fire. The props would glow, any metal outside the windshield would glow with electrical discharges, the radios would be completely useless from the static noise–even the VHFs, and occasionally an electrical, lightning-like streak would flash across the windshield. The windshields were conductive and were heated to make them less brittle. I never saw ball lightning though.

      Jim

    • That is the same sun spot, next time around. They do not “disappear” when they roll around the back. SOHO can still pick them up. They still exist and come back 13d later.

      • I have actually had people, with supposed educations, argue that the Sun does not rotate it only appears to because the Earth moves around the Sun. One even called me a flatearther because I “believed” the Sun spins. Yes, they are true believers and faithful followers of Brother Al Gore.

      • Actually, Greg it’s STEREO-A that “sees” the far side (in solitude until STEREO-B is recovered).

  4. As I have mentioned previously it is not unusual to see a bump up in daily satellite temperatures whenever we have a CME. If you look at the UAH daily value we see another example of this in July. The warming usually lasts 5-10 days before falling back down.

    https://ghrc.nsstc.nasa.gov/amsutemps/amsutemps.pl

    This is one way fewer sunspots/CMEs could affect our temperature. I have no idea why this happens and what the mechanism might be. Just something I have noticed.

    • spelling “thought”

      I also recall once reading something about a triple-satellite system that could observe the sun from the other side. Is there such a system?

      • STEREO-A shows the far side by itself after its B counterpart failed.

        “Communications with Solar Terrestrial Relations Observatory-B (STEREO-B) were lost on Oct. 1, 2014, due to multiple hardware anomalies affecting control of the spacecraft orientation.”
        https://stereo-ssc.nascom.nasa.gov/behind_status.shtml
        The STEREO satellites combined with SOHO or SDO nearside images would provide a 3-point 360 of Sol, with stereo imagery of the occulted events.

  5. Our esteemed visitor, Leif Svalgaard, has done tremendous work in helping NASA develop longer term solar predictions as a factor in space projects. His work has far more robust peer examinations than most other solar scientists and is way better than armchair amateur soundbites.

    • True story, Pamela. Anyone can gain great insight into all things solar by reading at his site, whether you agree with him or not. I enjoy his frank and unabashed style and his participation here.

  6. Mg II index data
    The Mg II data are derived from GOME (1995-2011), SCIAMACHY (2002-2012), GOME-2A (2007-present), and GOME-2B (2012-present). All three data sets as well as the Bremen Mg II composite data are available (see links below). In late years the GOME solar irradiance has degraded to about 20% of its value near 280 nm in 1995, so that the GOME data have become noisier. The most recent information on our Mg II data can be found in Snow et al. (2014).
    http://www.iup.uni-bremen.de/gome/gomemgii.html
    Ozone photochemistry is driven by the interaction of the Sun’s radiation with various gases in the atmosphere, particularly oxygen. The understanding of the basics of ozone photochemistry began with Chapman (1930), who hypothesized that UV radiation was responsible for ozone production and proceeded to lay the foundation of stratospheric photochemistry: the Chapman reactions. He proposed that atomic oxygen is formed by the splitting (dissociation) of O2 by high energy ultraviolet photons (i.e., packets of light energy with wavelengths shorter than 242 nanometers).

  7. What is this all about? Approximately once a week, Spaceweather.com and the students of Earth to Sky Calculus fly space weather balloons to the stratosphere over California. These balloons are equipped with radiation sensors that detect cosmic rays, a surprisingly “down to Earth” form of space weather. Cosmic rays can seed clouds, trigger lightning, and penetrate commercial airplanes. Furthermore, there are studies ( #1, #2, #3, #4) linking cosmic rays with cardiac arrhythmias and sudden cardiac death in the general population. Our latest measurements show that cosmic rays are intensifying, with an increase of more than 13% since 2015:
    http://spaceweather.com/

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