Right before Christmas, a gargantuan black fissure opened on the Sun. It was shaped like a question mark.

By Tom Yulsman | December 28, 2017 6:44 pm
question mark

An animation of images acquired by NASA’s SDO spacecraft shows a coronal hole developing and dissipating on the Sun between Dec. 18 and 22, 2017. (Movie created on Helioviewer.org)

It doesn’t really take much imagination to see the dark question mark forming and dissipating across most of the Sun’s surface in the animation above.

The images that make up the animation were acquired by NASA’s Solar Dynamics Observatory spacecraft between Dec. 18 and 22, 2017. And if you’re thinking that the question mark is some sort of optical illusion, guess again. The feature is very real: an unimaginably large fissure in the Sun’s atmosphere.

There’s nothing to be alarmed about. Features like this are completely normal. Scientists call them “coronal holes.”

I’ve written about coronal holes before, most recently almost exactly a year ago. Here’s my explanation of the phenomenon from that story, A new ‘hole’ in the Sun’s atmosphere has sparked stunning displays of the northern lights here on Earth”:

Coronal holes are areas where the Sun’s magnetic field opens toward space. This greatly enhances the solar wind, which consists of high energy particles that constantly stream away from the corona. The enhanced wind of hot particles blowing into space can move at speeds approaching 2 million miles per hour. That’s about twice the average velocity of the solar wind.

With so much hot material blowing outward, a darkened area — a so-called “hole” — is left behind on the Sun.

These features stand out best when viewed in extreme ultraviolet light, as is seen in the animation of false-color SDO images above.

The Sun appears yellow to our eyes because that’s the brightest wavelength of light that is visible to us. But the Sun emits light in many other wavelengths as well. SDO’s Atmospheric Imaging Assembly, or AIA instrument, images 10 different wavelengths of light coming from the Sun. Each one reveals different aspects of the sun’s atmosphere. For a detailed explanation, check out this post from NASA.

Here’s one thing SDO cannot help us with: What the Sun might be asking.

Perhaps what the New Year will bring?…

CATEGORIZED UNDER: select, Sun, Top Posts
  • StanChaz

    The sun is simply saying: why on earth did you every elect Trump.

    • dwolfcoach

      Plausible, but then most inanimate objects are smarter than the mafia-boss in chief. So the ?? Mark remains.

      • Nipple_Effect

        Pickles Rodham Clinton lost.
        Get over it and move on.
        If you’re addicted to her lying.
        She’s on her “It Was Everyone’s Fault But Mine” tour.
        And will be until she’s put in the ground.

        • Trench Wolfhound

          Yeah. Since Trump won the election, you shouldn’t have any criticisms about the President and should blindly follow him just like all those that are unfathomably loyal to the Liar in Chief.
          Don’t question or criticize the government… Unless they’re Democrats, then that’s fine. Otherwise ‘get over it’.

          • OWilson

            Spoken like a partisan! :)

          • Mike Richardson

            You would know, wouldn’t you? :)

          • OWilson

            Yeah, like you, they are a dime a dozen!

            Must rational folks accept the outcome of a democratic election! :)

          • Mike Richardson

            Less than half the country voted for him — we didn’t have full voter turnout, and of those that did, the majority voted for someone else. Even excluding third party candidates and write ins, he had less of the popular vote than Mrs. Clinton. So what you have said here is a lie. And you need to quit cutting and pasting that, “Your narcissism knows no bounds!”. In your case, it really is the pot calling the kettle black.

          • OWilson


            You need a primer on how elections are run in your country.

            And, you, Mikey, a government employee yourself?


          • Mike Richardson

            I’m well aware of how they work, as well as how dysfunctional they’ve become. Your statement, nonetheless, remains false. Hence, you are a liar. :)

          • OWilson

            If you want to be technical and prissy about it, unless you counted each cast ballot yerself, you have no idea how many votes each candidate got.

            Less than half the country voted for Hillary too!

            By your hissy, prissy standards, she would have been illegitimate too!

            Bye Mikey!

            You’re getting lonely again! A little attention seeking?

            What happened to your new friends? :)

          • Mike Richardson

            Could you just admit for once that you’ve stated something unequivocally false, and apologize? It’s one thing to deny climate change based on short-lived data and selective reading, but now you’re denying mathematical and historical fact. Trump did not have half the country voted for him, and Clinton did in fact have nearly 3 million more popular votes than Trump.


            “Hissy, prissy standards,” — LOL! So that’s your definition of the truth!? And I never claimed she had a majority, either. As for attention seeking, I post a lot less frequently than you do, so again — pot and kettle. Now by “friends,” if you’re referring to the other reality-based folks with whom I’ve conversed – – I assume they have better things to do at the moment, as I shortly will. If you’re referring to the “militant compatriots,” on the other hand – – why, they’re watching you right now, of course! 😉

          • OWilson

            Half an apple, half a glass, half the world, are figures of speech, that only hissy, prissy, panty waist, silk stocking socialists, would ever get their shorts in aknot about!

            Figures of speech ar not lies, Mikey, but you wouldn’t know the diference!

            You’re getting lonely again?

          • OWilson

            Sinse you ask, these are my standards:


            “I remember landing under sniper fire. There was supposed to be some kind of a greeting ceremony at the airport, but instead we just ran with our heads down to get into the vehicles to get to our base.”

            “If you like your healthcare plan, you will be able to keep your healthcare plan. PERIOD!”

            “If you like your doctor, you will be able to keep your doctor, PERIOD!”

            “We’re going to lower your premiums by up to $2500 per family per year.”

            And who can forget the hushed silence as the Dear Leader in his new clothes opined, “This is the day (my election) when the seas will cease to rise, and the planet will begin to heal”, Halleilujia (that last bit was mine!)

            And you throw a hissy for whn I refer to half the country?

            You really need to get a life instead of following me around for the only little attention you can raise on these blogs!

            But I’ll be here for you, Mikey, sometimes!

          • Mike Richardson

            LOL! I’m getting lonely? – – but you devoted two separate posts of deflection, projection, and childish insults to me when you could have just answered my question by simply stating, “No, I cannot admit to saying things that are incorrect or outright false, because only other people are ever wrong.” That’s basically the point you’ve made with your posts. Contrary to what you think, I would have been perfectly fine with no response, or pleasantly surprised by a post showing some humility and self reflection, but your typical responses do provide me with amusement while also further diminishing your credibility. That’s what happens when you continue to defend the indefensible, such as our ever eloquent and non-racist President. ;). Please, keep up the good work!

          • OWilson

            Bye Mikey! :)

      • I_of_Horus

        Are you sure the sun is inanimate? Maybe it lives on a different timescale. ^_^

  • cannotvote

    Outrage that the deep-state – Hellary et al, haven’t been prosecuted yet! The Mayans were aware of this – and they state the great Sun Dog will bark at the irreverence of a lying she devil, and who she represents!

    • JiGGLeBiLLy


      • cannotvote

        No its true – history repeats itself!

  • mea_mark

    ‘Always question authority’, just a friendly reminder from the supporter of life in this solar system.

  • John Do’h

    Maybe our Sun will have a gas fart flare out and exterminate 99% of life on the Earth including humans… new life will evolve from rats, dandelions, tardigrades, and lionfish. So it goes.

    • misterveritas666

      No love for cockroaches?

  • Erik Bosma

    The sun is just curious how serious we are about continuing existence. One sun fart and we’re done for. Well, maybe a few…

  • Ricardo Garcia

    How did we get from science to politics? Its human nature to fight with ourselves! I wonder how long it will be before we exterminate all life in this world?

  • TLongmire

    According to the video the bird questions the horses path.

    • TLongmire

      🤔maybe as relevant as any other post👎



ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

About Tom Yulsman

Tom Yulsman is Director of the Center for Environmental Journalism and a Professor of Journalism at the University of Colorado, Boulder. He also continues to work as a science and environmental journalist with more than 30 years of experience producing content for major publications. His work has appeared in the New York Times, Washington Post, Audubon, Climate Central, Columbia Journalism Review, Discover, Nieman Reports, and many other publications. He has held a variety of editorial positions over the years, including a stint as editor-in-chief of Earth magazine. Yulsman has written one book: Origins: the Quest for Our Cosmic Roots, published by the Institute of Physics in 2003.


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