For your viewing pleasure: Active Region 1302

By Phil Plait | September 27, 2011 6:14 am

Yesterday, I linked to a picture taken a few days ago by Alan Friedman that showed the sunspots that are currently blowing their lids with flares. He just sent me a new shot, taken yesterday, and… well. It’s stunning. Presenting the sunspot cluster Active Region 1302:

Wow. [Click to ensolarnate.]

It’s hard to imagine just how enormous this cluster is. So to help, I cropped out the big spot on the left and put the Earth to scale next to it.

So yeah. That’s our whole planet.

Sunspots are big.

In fact, these guys are so big I tried to get a picture myself using binoculars, projecting the image onto a white board. Unfortunately, I couldn’t get my set up to work well and all the pictures were out of focus. You might want to try it yourself, but be warned: the bright Sun can damage optics, so you might fry your binocs. Also, of course: NEVER LOOK AT THE SUN. Not with your eyes, not through a telescope, not through binoculars. There are ways to do that, but it takes specialized equipment, and it’s not worth the risk if you don’t know what you’re doing. The Stanford Solar Center has some advice about all this.

Anyway, I expect we’ll see more activity out of these spots over the next few days. Should be a fun ride.

Related posts:

Awesome X2-class solar flare caught by SDO
Scientists see sunspots forming 60,000 km below the Sun’s surface!
The birth of a sunspot cluster
Followup: Sunspot group’s loopy magnetism

CATEGORIZED UNDER: Astronomy, Cool stuff, Pretty pictures
MORE ABOUT: Alan Friedman, Sun, sunspot

Comments (29)

  1. alfaniner

    it’s not worth the risk if you don’t know what you’re doing.

    Everybody thinks they “know what they’re doing.” Trust me. You don’t.

  2. The northern lights were seen last night as far south as Michigan, New York, South Dakota and Main according to (NASA).
    A HD video of what the northern lights look like during a strong geomagnetic storm as we had yesterday can be seen at

  3. Chris

    Looks like the Eye of Sauron. Hopefully it’ll put out some big flares so we can get some more auroras.

  4. Jason Dick

    But…but…focusing the intense heat of the Sun from a big telescope directly into my eyes sounds like fun! I mean, my eyeballs might catch on fire, but before that it would be a barrel of laughs (all 0.1 seconds of it…).

  5. Caleb

    Wow. Insane. I can’t actually wrap my mind around how big the sun actually is. Awesome post.

    Just found this as well – “A time-lapse taken from the front of the International Space Station as it orbits our planet at night.”

    I frikken LOVE being alive in this age!

  6. Kenn

    of course there are always the crackpots who do stare at the sun…

  7. Chris

    I once projected the sun onto card with my 20X80 binoculars but I made the mistake of leaving one of the plastic eyepiece covers on and the heat bored a hole right through it in about 3 seconds! Moral – cover the object glass end.

  8. Mark

    Astronomy: Reminding you how small you are since 7 January 1610.

  9. Chris A.

    “Do not look at the sun through unfiltered telescope with remaining eye.”

  10. CameronSS

    The observatory at my hometown college has a prepared answer for vistors who ask about pointing their telescope at the sun. It involves an explanation for how long it would take the focused sunlight to burn through to the back of your head. It was less than a second, IIRC.

  11. Trikester

    I accidentally discovered a safe way to observe the sun with little equipment many, many years ago.

    All you need is a good quality mirror. Stand back and use the mirror to reflect the sun’s light on the shaded side of a building or other object. If the mirror is flat enough and the building or object makes a good enough screen, then, voila! An image of the sun. Bigger mirror, bigger image.

    I discovered it when I asked myself why a rectangular signal mirror invariably produced a round patch of reflected sunlight at distances longer that a few feet, ie, signalling distances. I’m sure someone here can come up with some math to figure the optimum distance for a mirror of any particular size.

    I like to use it to watch solar eclipses, yet I never see anyone discuss it when talking about safe ways to watch eclipses.
    You can even see those dark little spotties in the image. Perhaps not in any detail, but still…

  12. Caleb

    I can remember being at a boy scout camp when Shoemaker-Levy collided with it. Serendipitously, I was getting my astronomy merit badge and they had a very high-powered telescope. We could just make out the impacts from the comet.

    Also, the instructor had a lens cover (looked like the glass on a welding mask) which allowed us to point the telescope at the sun to see it close-up.

    Seeing the earth superimposed like that makes me think of how much fighting and troubles we have over access to resources on this planet and how even modest colonization and/or accessing the raw resources in our solar system can alleviate the resource struggle and promote peace.

  13. Manuel

    If the “lens cover” went on the eyepiece end of the scope, it was extremely dangerous. Older “department store” scopes came with this type of solar filter (luckily the practice seems to have been discontinued). The problem with this sort of filter is that it goes at the end of the scope where the rays are most concentrated, so it gets very hot. This can cause the glass that forms the filter to crack due to thermal expansion, and as soon as it cracks sunlight immediately bursts through and leaves you permanently blind.

    The only safe solar filter for a telescope is a full aperture filter specifically designed for solar observing. These go on the objective (front) end of the scope and cover it completely, and look like opaque silver. They can be made out of glass or film, but you should always acquire them from a reputable dealer of astronomical equipment. Aluminized mylar, even though it looks like solar film, is _not_ sufficient. Also, the filter should be checked regularly for pinholes. A few small pinholes are expected and not a problem, but anything more than that requires replacing the filter. Also, unless you have a full aperture filter for your finder scope, you should keep the lens covers on it.

  14. To Chris P… thanks for sharing that link to the Trouvelot prints via the NY Public Library. We have a set in the downtown Buffalo Library as well. It is a fantastic series of prints though sometimes, as is the case with the sunspot observations, a little fantastical too.

  15. James porter

    How do astronauts drink water in space i need to knw

  16. Doug

    Pinhole! Think pinhole camera! Safer for the eyes! MOST binoculars and telescopes have COATED OPTICS. The sun can burn them right off!! That said, if you HAVE a full aperture filter, fine.

  17. Ilya

    There is a safe way to observe the sun directly through binoculars, but it’s rarely available. You can watch it at sunset, when it’s really filtered through the atmosphere, and if there are no clouds on the horizon. When you can look at the sun anyway, and everyone does, you can also watch it through binoculars. I’ve been able to see a lot of sunspots this way through 7X50 binoculars around 2003.

  18. Pepijn

    NEVER LOOK AT THE SUN. Not with your eyes, not through a telescope, not through binoculars

    I don’t think think you should lump those together like that. It makes it seem as though they’re equally dangerous, but while people look at the sun with their eyes all the time with no ill effects, even a single glance at it through binoculars or a telescope will likely fry your eyes instantly.

    Putting all of them in the same category implicitly downplays the danger of the two vastly more dangerous options, and therefore might actually put people at risk. They might think: “I look at the sun all the time with my eyes and nothing ever happens, so looking at it through binoculars probably isn’t actually that dangerous either”…

  19. Fortunately I CAN look ‘directly’ at the sun without damage. I’ve got a nifty pair of dark glasses designed specifically for solar viewing. Which I wear.


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