Sharpest Ever Images of the Sun

Astronomers at Big Bear Solar Observatory in sunny California have upgraded their 1.6-meter telescope with a new adaptive optics system. The scope is now producing the highest-resolution images ever taken of the Sun.

The Big Bear Solar Observatory recently upgraded its New Solar Telescope with an advanced adaptive optics system. Now the telescope is showing a sharper-than-ever view of the Sun.

The telescope cuts through the blurring effects of Earth’s atmosphere by sending light from its 1.6-meter primary mirror into a deformable mirror only the size of a fist. The mirror bends and twists hundreds of times every second to respond to changes in the atmosphere. Small-scale features on the Sun are used as the telescope's "guide stars" — the camera that detects distortions in the atmosphere takes 1,500 frames a second, so a solar feature that lasts for even 10 minutes might as well be immortal for the purpose of adaptive optics, says Philip Goode, director of the Big Bear Solar Observatory.

There used to be 97 actuators guiding its movement — now it has 357. With the new system, the telescope will resolve down to 0.05 arcsecond even at the bluest wavelengths, where light is the most difficult to focus. That means the telescope can resolve solar features just twice the size of Manhattan.

The images below are the telescope’s “engineering first light” — the first light seen by the telescope as the higher-order adaptive optics undergoes testing. The testing should be complete by October.

Already, the system is producing some of the sharpest pictures ever taken of the Sun’s visible surface. The images reveal fine details in sunspot structure.

Sunspot features
Big Bear Solar Observatory's New Solar Telescope is taking some of the sharpest ever images of the Sun, revealing fine details described further in the text.

From left to right:

  1. The arrow points to light-colored dots in the dark center of the sunspot. Some of these dots look like coffee beans: two elongated bright kernels separated by a thin dark line?.
  2. The arrow points to dark channels of filaments?crossing through a sunspot’s light-colored outer edge.
  3. The circle highlights a bright, bow-shaped ridge surrounding a somewhat darker area with a bright straight?lane. Magnetic field lines are likely emerging from this feature.
  4. The arrow points to an elongated bright point, which is likely a highly inclined tube of magnetic flux.
  5. The arrow points to the center of a small micro-pore, where the strong magnetic fields between granules meet.
  6. The circle highlights a larger, daisy shaped micro-pore.

Another image taken two days later shows that the same sunspot has developed a penumbra, the lighter-colored edge. The boiling motion of solar plasma, known as granulation, is clearly visible in both images.


14 thoughts on “Sharpest Ever Images of the Sun

  1. Jack Bos

    WOW! These pics of the sun are outstanding. I am waiting to see more of these with the explainations/arrows and stars. I have been facinated by the sun and moon for as long as I can remember. Thanks for getting me excited about the sun again…

  2. Richard Carroll

    So, there are no space telescopes producing comparably sharp images?

    I look forward to the time when researchers have had the chance to track the development of many solar details.

  3. Monica YoungMonica Young

    Hi Richard, great question! Space-based telescopes have a huge advantage because they can get above Earth’s atmosphere, but the disadvantage is that it’s harder to get big aperture scopes into orbit. Philip Goode, the director of the BBSO, informed me that the largest aperture telescope in space is 0.5 m, so it has 1/3 the resolution that a 1.6-meter telescope would have. The 1.6-meter New Solar Telescope comes close to the resolution it would have in space because of its adaptive optics system.

  4. Tír-Ná-NóG

    Beautiful images. Even in B/W, the photographs remind me of a slice of orange detailing the delicate surface facets.

  5. John Murrell

    Great Image

    The next challenge must be to image the ‘dark’ centre of the Sunspot to see what is happening lower down in the atmosphere. The falling streaks all seem to have bright spots at the base – it would be really great to see what caused that. There also appear to be isolated bright spotsin the dark region.

    I presume the problem with imaging the dark area is the contrast ratio. Would it be possible to do this with a mask that either hides or dims the bright surface ? The challenge would be to get the mask made and installed before the Sunspot changed shape.

  6. Anthony BarreiroAnthony Barreiro

    These are really sharp pictures! From looking at the Sun through small telescopes with white-light solar filters, I’ve learned that Earth’s atmosphere is much more turbulent during the daytime than it is at night. So adaptive optics should be very beneficial on a solar telescope!

  7. Robert

    Monica Young,
    isn’t the aperture of the Hubble space telescope 2.4 meters?
    Double the aperture quadruples light gathering,double aperture doubles resolution. A 1.6 meter scope would have over 6 times the resolution of a .5 meter scope.
    Hubble gathers over 20 times the light of what you have been misinformed is the largest aperture space telescope at .5 meters.
    If Hubble had the right filters an adaptive optic 1.6m scope could not touch its resolution or light gathering capability,simply since it does not have to contend with earth’s atmosphere and is much larger in size.
    Maybe the guy at BBSO meant to say the largest solar space aperture is .5 meters?
    Hubble has taken images of the solar surface,with it’s much larger aperture than the ground based 1.6 Meter BBSO scope and no atmospheric distortion why isn’t it taking the highest resolution pics?

  8. Richard Carroll

    Robert, I appreciate the math in your post, but I believe it has a bit of misinformation – that there are solar images taken by Hubble. From Wikipedia’s Hubble article:

    Observations cannot take place when the telescope passes through the South Atlantic Anomaly due to elevated radiation levels, and there are also sizable exclusion zones around the Sun (precluding observations of Mercury), Moon and Earth. The solar avoidance angle is about 50°, which is specified to keep sunlight from illuminating any part of the OTA.

    However, googling "Hubble telescope sun pictures" (without quotes) yielded dozens of hits. But when I examined many in detail, it would turn out to be something like "artist’s conception", or some kind of misidentification. These are on blogs and such, not primary sources. One convincing image seems to be from the Solar Dynamics Observatory. It’s very likely you have seen "sun images from Hubble", so it’s logical that you would come to believe this, but I think these are all errors of some kind. A good reminder that everything on the internet is not true.

  9. JOHN BARRY PICKUPBarry Pickup

    Excellent pictures,but I fail to see the fine details mentioned in the text, which may not be resolved on my 17" laptop screen. I was privileged some years ago to view solar images by projection at Dunsink Observatory (Dublin, Ireland) with the 12" refractor there,to be honest the resolution seemed much the same back then, with the convective cells being clearly visible, there is however more detail visible in the sunspot itself in the ‘Big Bear’ images. Many thanks

  10. kdconodJohnI

    Robert: HST has never taken images of the Sun – it is not equipped with solar filters (its cameras and instruments are designed for imaging the faintest objects in the universe not for solar work).

  11. Sergio Silva

    This telescopes will be a good tool to, someday, we will have a more predictable weather forecast of the sun. Where were taken this pictures? In equatorial or in the poles zone of the sun? Could be Infrared composed images more helpfully to understand the sun? In visible light all thing goes very dramatic, in other hand, in infrared we can spot the events that origin problems in earth and studying periods of time when we can reached more closely with an spacecraft in a whatever mission. (I think)

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