Starship Asterisk*

An Unexpected Rocket Plume over San Francisco

Explanation: What is that unusual light in the sky? A common question, this particular light was not only bright but moving and expanding. It appeared just as the astrophotographer and his friend were photographing the Golden Gate Bridge in San Francisco, California against a more predictable night sky. They were not alone in seeing this unusual display -- at least hundreds of people in California reported a similar sight. The consensus of experienced sky observers was that the plume resulted from a rocket launch -- an explanation that was soon confirmed as an unpublicized test of a submarine-launched, unarmed, Trident II D5 nuclear missile. Such tests are not uncommon but do not usually occur just after sunset near a major metropolitan area -- when they are particularly noticeable to many people. Were plume images not posted to the Internet and quickly identified, such a sky spectacle might have been understood by some to be associated with more grandiose -- but incorrect -- explanations.

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Why is the plume so blue?

Ann

Ann wrote:
Why is the plume so blue?

• For the same reason the sunlit sky is blue.

http://apod.nasa.gov/apod/ap150905.html wrote:
As the rocket rises above Earth's shadow,
its fiery trail becomes an eerie, noctilucent exhaust plume glinting in sunlight.

It's obvious...

Ann wrote:Why is the plume so blue?

Ann

It might contain a particular gaseous element? Rocket plumes are not my forte unfortunately.

There was most likely a hefty dose of saturation boost given to the photo. You can see other images of the same plume are nowhere near this blue.

Funny there was a photographer poised so ideally, at just the right time, on Veterans day, as military budgets are under debate in congress....

heehaw wrote:Funny there was a photographer poised so ideally, at just the right time, on Veterans day, as military budgets are under debate in congress....

"Hee-haw" indeed.

And if there were *not* this image of the event then it would seem "Funny that there were *no* photographers who were shooting the sunset at one of the most photographed sites in the world..."

Moreover, whilst it may be true that "...military budgets are under debate in congress..." (when are they not? And just how much debate about such there actually is is debatable) an image such as this, with the whisper of the horrors of nuclear war hidden in the bright blue rocket plume, could as well fuel opprobrium as approval for increased military spending.

Freemasonry must get a bye this round ... and, yes, one does feel the photographer got a bit too carried away with the blue-saturation slider.

Is it only me, or...

Why does it appear that the image seems abnormally large? The apparent image of the rocket itself seems to be leading the plume. But at the likely distance from the rocket, it shouldn't be nearly that large.

No chance there was some photo manipulation here?

HellCat wrote:No chance there was some photo manipulation here?

The event was captured by many cameras all along the coast. It's a real depiction of a real event. There was surely editing done for colors and other nuances like sharpening, but probably not resizing the plume or moving it around in some way.

HellCat wrote:
Why does it appear that the image seems abnormally large? The apparent image of the rocket itself seems to be leading the plume. But at the likely distance from the rocket, it shouldn't be nearly that large.

You are seeing a rocket shaped plume. The rocket is quite tiny in comparison.

Ok....if this was launched from a submarine...why does it look like it came from the landward side of the picture?
Unless it is waaaaay to the South, and shot from Monterrey Bay, or off of Los Angeles, or San Diego...

:---[===] *

After yesterday's teaser I thought it was going to be this.
Luckily he survived!

Boomer12k wrote:Ok....if this was launched from a submarine...why does it look like it came from the landward side of the picture?
Unless it is waaaaay to the South, and shot from Monterrey Bay, or off of Los Angeles, or San Diego...

:---[===] *

The sub was in the Pacific Test Range, north west of Los Angeles.

Ron-Astro Pharmacist wrote:After yesterday's teaser I thought it was going to be this.

Space_center.jpeg

Luckily he survived!

Aww, poor frog!

I can't help it, I like certain animals because I find them cute, like hedgehogs and kittens and frogs. Mr Spock would not be pleased with my illogical reactions.

On a different note, I've been wanting to say that you've posted some tremendously interesting articles, videos and comics lately, Ron. Thanks a lot!

Ann

Sorry, as a long retired military veteran I take exception to the labeling the missile as a "Trident II D5 nuclear missile" for two reasons: A. the caption stated it was "unarmed" indicating that none of the potentially 14 thermonuclear MIRVs were on board and B. it's a 3 stage solid-fuel, guided missile with no nuclear fuel, therefore it's not a "nuclear missile".

The used label is misleading and typical of writers that don't really do their homework.

Medik 1-7 <;,><

Medik 1-7 wrote:Sorry, as a long retired military veteran I take exception to the labeling the missile as a "Trident II D5 nuclear missile" for two reasons: A. the caption stated it was "unarmed" indicating that none of the potentially 14 thermonuclear MIRVs were on board and B. it's a 3 stage solid-fuel, guided missile with no nuclear fuel, therefore it's not a "nuclear missile".

The used label is misleading and typical of writers that don't really do their homework.

While your point is taken, it is worth noting that the Trident SLBM is specifically intended to carry nuclear weapons, and is conventionally referred to (including in Navy literature and technically oriented defense information sources) as the Trident II D5 nuclear missile system, with tests qualified by "unarmed". While you are technically correct, this usage is conventional, and as such doesn't reflect on the quality of reporting.

Boomer12k wrote:Ok....if this was launched from a submarine...why does it look like it came from the landward side of the picture?
Unless it is waaaaay to the South, and shot from Monterrey Bay, or off of Los Angeles, or San Diego...

:---[===] *

The Trident missile was fired from the USS Kentucky off shore from Los Angeles with LAX air traffic being rerouted to exclude flying over the Pacific Ocean. Apparently the U.S. Government keeps tests like this from the public (for obvious reasons) but will inform Airports as needed for flight safety

This WAS photoshopped although photoshop might not what he did to it, maybe another software. I have seen this photographers other work and he brags that he does not photoshop, but he does boost everything in lightroom and says it is straight our of the camera even when it's not. Although I applaud him for getting A shot, it just wasn't the same shot he has posted here. I'm in SF....The hills are not that green at night nor the lights that yellow gold or the sky that blue after 6pm now. There's another photo from a different photographer that was with this guy and hia photo shows the missile smaller and farther away. Plus the other photo does not have all the color saturation added like this photo. You should ask for the RAW image NEF file.

howdydoody wrote:There's another photo from a different photographer that was with this guy and hia photo shows the missile smaller and farther away. Plus the other photo does not have all the color saturation added like this photo. You should ask for the RAW image NEF file.

You should keep in mind the evolving and expanding nature of the cloud produced by the rocket. At some earlier point in time it was smaller. Because you did not add any links to the pictures you were talking about, I took a look at the Facebook page linked to in the APOD description and found a picture Abe took of the RAW image in the preview screen on his camera.
https://www.facebook.com/photo.php?fbid ... =3&theater

Here is another link to the image that will probably work even if one is not logged into Facebook:
https://scontent-lga3-1.xx.fbcdn.net/hp ... 7777_o.jpg

(If it still doesn't work for someone, I'll attach the image to a post.)

Although I can't open the photo information my Kindle, this looks like it would be about a 5 second exposure. Your eye processes light in 1/30th second and so the locale wouldn't appear as depicted in the image to your eyes if you were standing there. But with the camera iris open for 5 seconds, the CCD receives about 150 times the light that your eyes normally do. Any available light will be increased in the image compared to normal visual perception

Amazing shot. This view is looking South, so I guess from the description, the missile was headed North up the coast and then, just before this shot, banked to the West, out to sea. I suppose there would have been lots more fears, if it had turned inland.

geckzilla wrote:

howdydoody wrote:There's another photo from a different photographer that was with this guy and hia photo shows the missile smaller and farther away. Plus the other photo does not have all the color saturation added like this photo. You should ask for the RAW image NEF file.

You should keep in mind the evolving and expanding nature of the cloud produced by the rocket. At some earlier point in time it was smaller. Because you did not add any links to the pictures you were talking about, I took a look at the Facebook page linked to in the APOD description and found a picture Abe took of the RAW image in the preview screen on his camera.
https://www.facebook.com/photo.php?fbid ... =3&theater

Here is another link to the image that will probably work even if one is not logged into Facebook:
https://scontent-lga3-1.xx.fbcdn.net/hp ... 7777_o.jpg

(If it still doesn't work for someone, I'll attach the image to a post.)

Interesting, Geck. Thanks. But even though the wide "halo" of the plume is now yellowish, the bright, narrow "jet-like contrail" is still very blue.

Ann

This is the pic from the other photographer he was with. Take a look at the difference when shot at the exact same time. This one is more realistic and looks like it is not manipulated. http://www.slrlounge.com/lucky-photogra ... ime-lapse/

Also on that NEF file link you posted the time is 9:15 but he said it was shot after sunset, unless his camera settings are wrong.

Your "shot" appears to be a frame capture from a video file, the Vimeo "Time Lapse" linked below the image. During the recording of the image, you can clearly see the effect of a wider iris opening on the brightness of the image as the video file plays. You can also clearly see the 3 stage separations as the flight progresses. The only real difference between the "more realistic" image and the APOD image is the amount of time that the CCD was allowed to gather photons before the Image was completed.