APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

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APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

Post by APOD Robot » Sat Aug 30, 2014 4:12 am

Image The Starry Sky under Hollow Hill

Explanation: Look up in New Zealand's Hollow Hill Cave and you might think you see a familiar starry sky. And that's exactly what Arachnocampa luminosa are counting on. Captured in this long exposure, the New Zealand glowworms scattered across the cave ceiling give it the inviting and open appearance of a clear, dark night sky filled with stars. Unsuspecting insects fooled into flying too far upwards get trapped in sticky snares the glowworms create and hang down to catch food. Of course professional astronomers wouldn't be so easily fooled, although that does look a lot like the Coalsack Nebula and Southern Cross at the upper left ...

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Ann
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Re: APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

Post by Ann » Sat Aug 30, 2014 5:12 am

That looks fantastic! :D

The Coalsack is clearly the dark shape at upper center, but I can't spot the Southern Cross. :wink:

Tell me, are those glowworms really glowing blue, or is that a trick of the photographer's light, or a trick of the processing of this picture?

I'm asking because fireflies typically glow yellow. You can't mistake their color for the average color of the sky's bright stars.

Ann
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deathfleer

Re: APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

Post by deathfleer » Sat Aug 30, 2014 5:21 am

I was initially, fooled. The "stars" looked strange

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Chris Peterson
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Re: APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

Post by Chris Peterson » Sat Aug 30, 2014 5:52 am

Ann wrote:Tell me, are those glowworms really glowing blue, or is that a trick of the photographer's light, or a trick of the processing of this picture?
They are actually blue. Although the luciferin chemistry is very similar to that of fireflies (and many other bioluminescent critters), subtle changes in pH and other factors can result in very different colors, from red through blue.
Chris

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Re: APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

Post by rwlott » Sat Aug 30, 2014 12:09 pm

Ann wrote:The Coalsack is clearly the dark shape at upper center, but I can't spot the Southern Cross. :wink:
All I see in the upper left is Orion's belt.

Russ

Norm

Re: APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

Post by Norm » Sat Aug 30, 2014 2:43 pm

So deceiving is the picture of glowworms, that if you did not publish the explanation, and asked experienced astronomers for an explanation, they would probably theorize that it is a unknown part of the Milky Way Galaxy, rich in hot, young blue massive stars.

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Re: APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

Post by Boomer12k » Sat Aug 30, 2014 11:31 pm

Fooled indeed...at first I thought it was a "dusty" nebula...but saw the wall, the silhouette...and the "Hills"....but I thought it was OUTSIDE...then got the idea it was one of those Cave Shots, as we had seen before...but the glow was out the top of the cave, and was still stars...BUT DID NOT LOOK RIGHT, as WE DON'T SEE DUSTY NEBULA!!!!,------ until I read the caption....amazingly similar...

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Re: APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

Post by BillBixby » Sun Aug 31, 2014 5:19 pm

I am under the impression there are no stars or sky in this picture. Just the worms trying to fools us into thinking we are seeing stars. I have glow-in-the-dark stars and planets on the ceiling above my bed. Always a clear sky over me as I sleep.

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Re: APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

Post by DavidLeodis » Sun Aug 31, 2014 6:31 pm

I accessed this APOD for the first time today and found that the 'Phill Round' link in the credit was dead the numerous times that I tried over many hours. When in the website through the "glowworms scattered' link the webpage brought up has links to other items in the website but I could not open some of those links and instead got a message "Your security settings have blocked an untrusted application from running". That was a surprise as I cannot recall ever getting a security block message when using the Internet. I suspect (hope!) that it is all innocent, but it does cause me concern.

PhotoPhill

Re: APOD: The Starry Sky under Hollow Hill (2014 Aug 30)

Post by PhotoPhill » Sun Apr 05, 2015 8:37 am

Yes they really are blue. They emulate stars to attract insects into their sticky fishing lines. Its an amzing site that I never tire of :wink: PhotoPhill
p.s I shot this cave passage that is big enough to fit an ocean liner inside. Practically most of the cave is coated with billions of glowworms.
(Nikon D7000 ISO 800, f3.5, 2 minutes with a single Metz flash and a pocket wizard (Plus a little LED fill in lighting)
Ann wrote:That looks fantastic! :D

The Coalsack is clearly the dark shape at upper center, but I can't spot the Southern Cross. :wink:

Tell me, are those glowworms really glowing blue, or is that a trick of the photographer's light, or a trick of the processing of this picture?

I'm asking because fireflies typically glow yellow. You can't mistake their color for the average color of the sky's bright stars.

Ann