Changing Planet

Sea Serpent Eats Cosmic Diamond Ring

Astronomers using the Very Large Telescope in Chile have captured this eye-catching image of planetary nebula Abell 33. Created when an aging star blew off its outer layers, this beautiful blue bubble is, by chance, aligned with a foreground star and bears an uncanny resemblance to a diamond ring. This cosmic gem is unusually symmetrical, appearing to be almost perfectly circular in the sky. Credit: ESO

A  cosmic diamond ring is the best way to describe the haunting beauty of a distant star in its final moments of life.

Located some 2,500 light-years from Earth within the belly of a mythical water snake, Abell 33 (also known as PK238+34.1) represents the final remains of a sunlike star that has thrown its atmosphere into space, releasing a vast bubble of gas and dust called a planetary nebula.

This stellar remnant is captured in striking detail never seen before, thanks to the Very Large Telescope in the high desert of Chile.

The chance alignment of the nebula and a brilliant, sparkling star together create the mesmerizing diamond-ring effect.

Look carefully to see, just off-center in the image, the tiny, Earth-size core of the nebula’s progenitor star. It still burns with enough energy to bellow copious amounts of ultraviolet radiation into surrounding space, which will make the bubble glow for tens of thousands of years before fading into darkness.

See for Yourself

Abell 33 belongs to a celestial catalog of 86 planetary nebulae put together by astronomer George Abell back in 1966. It is located inside the southern constellation of Hydra, the Water Serpent.

Skychart showing the moon in the early evening of April 10, wedged between the bright star Regulus and the much fainter Iota Hydrae. The distant planetary nebula Abell 33 sits just below the orange star in the constellation Hydra.  Credit: Starry Night Software / A.Fazekas
This sky chart shows the moon in the early evening of April 10, wedged between the bright star Regulus and the much fainter Iota Hydrae. The distant planetary nebula Abell 33 sits just below the orange star in the constellation Hydra. Credit: Starry Night Software/A. Fazekas

To catch a glimpse of the 12th-magnitude ghost bubble, you will require a medium-size backyard telescope with an 8- to 12-inch mirror and dark skies. Start your hunt in the southeastern skies and locate the faint (but visible to the naked eye) star Iota Hydrae, which represents the neck of the serpent constellation. This will act as the stellar guidepost to find the tiny cosmic bubble.

Some landmarks in the sky on April 10 include the gibbous moon, which will appear wedged between the bright star Regulus in the constellation Leo, above Iota Hydrae. The much fainter orange-hued snake star will appear below the moon. The glare of the moon will wash out many faint stars, so use binoculars to pinpoint Iota Hydrae.

This wide-field view shows the sky around the planetary nebula Abell 33, which appears as the ghostly blue circle near the centre of the picture. Many faint galaxies are also visible and the bright orange star at the top is Iota Hydrae, which is bright enough to be seen with the naked eye. Credit: ESO/Digitized Sky Survey 2. Acknowledgement: Davide De Martin
This wide-field view shows the sky around the planetary nebula Abell 33, which appears as the ghostly blue circle near the center of the picture. Many faint galaxies are also visible. The bright-orange star at the top is Iota Hydrae, which is bright enough to be seen with the naked eye. Credit: ESO/Digitized Sky Survey 2. Acknowledgment: Davide De Martin

Now that you know where Iota Hydrae is located, on an upcoming moonless night use a low-power eyepiece to scan 1.5 degrees (the width of three full moons) below the star to see Abell 33. Using high magnification—around 150x—will reveal the nebula as a very tiny, faint, gray disk.

While backyard instruments won’t produce a spectacular sight the way a giant observatory will, it is still awe-inspiring to witness the death of a distant cousin of our sun.

Follow Andrew Fazekas, the Night Sky Guy, on TwitterFacebook, and his website.

Andrew Fazekas, aka The Night Sky Guy, is a science writer, broadcaster, and lecturer who loves to share his passion for the wonders of the universe through all media. He is a regular contributor to National Geographic News and is the national cosmic correspondent for Canada’s Weather Network TV channel, space columnist for CBC Radio network, and a consultant for the Canadian Space Agency. As a member of the Royal Astronomical Society of Canada, Andrew has been observing the heavens from Montreal for over a quarter century and has never met a clear night sky he didn’t like.
  • Christian

    On April 8th my family and I saw a huge, perfectly round circle of clouds (at least that is what we thought they were ) around the moon. It was an amazing sight!

  • Teresa L.Walker Frankeny

    Fascinating….Mankind Seeks and finds… emulates…kind of hard to blame him or her….pyro- techniques….Glitter….Star lights…… and Still Quiet Nights….Yes….I like this much better… A Star to Gaze at No More, but I will remember….

  • Payal Gudhaka

    Amazing information! 🙂

  • Justin

    Hey Christian sounds like you saw moon rings caused by moonlight being refracted by ice crystals in Earth’s atmosphere. I too was amazed the first time I saw one of these halos and continue to be so. Check out this website for more info on this and other moon light phenomena: http://home.hiwaay.net/~krcool/Astro/moon/moonring/

  • jeff gover

    Seeing that star blow up makes me think about how grateful I should be for every day I wake up. We never know when something like that could happen to our earth. Cherish the moments.

  • litz

    Tnx for hi tech we see the beauty of the universe which God created masterpice

  • nicholas

    aaahhhh i love space God is good

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