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APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 5:06 am
by APOD Robot
Image Earth at Night
Hi!
Western Australia and many other strange lights are explained in the thread and also here, officially. Please read it first before you accidentally ask about something that has already been explained!
Explanation: This remarkably complete view of Earth at night is a composite of cloud-free, nighttime images. The images were collected during April and October 2012 by the Suomi-NPP satellite from polar orbit about 824 kilometers (512 miles) above the surface using its Visible Infrared Imaging Radiometer Suite (VIIRS). VIIRS offers greatly improved resolution and sensitivity compared to past global nightlight detecting instrumentation on DMSP satellites. It also has advantages compared to cameras on the International Space Station, passing over the same point on Earth every two or three days while Suomi-NPP passes over the same point twice a day at about 1:30am and 1:30pm local time. Easy to recognize here, city lights identify major population centers, tracking the effects of human activity and influence across the globe. That makes nighttime images of our fair planet among the most interesting and important views from space.

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Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 5:26 am
by donalgary
Why does Alaska appear much brighter than Hawaii?

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 5:40 am
by Chris Peterson
donalgary wrote:Why does Alaska appear much brighter than Hawaii?
Does it? I'd say the interior of Alaska looks about the same as the interior of the Big Island.

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 5:46 am
by DougK
I am intreged as to the origin of the huge number of lights in the central part of Western Australia and parts of South Australia and Northern Territory. These are either clearly anomolies or the spinifex faries must have been having a party.

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 5:49 am
by neufer
donalgary wrote:
Why does Alaska appear much brighter than Hawaii?
  • 1) Oil production.
    2) Exaggerated scale in Mercator-like projection (especially for oil production region).
    3) Hawaiians live closer together than do Alaskans.
    4) Hawaiian lights from middle of the night (after folks have gone to bed)
    . whereas Alaskan lights from late morning or early evening.

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 6:27 am
by mstabb
The outback of Australia is brighter than the rest of the country - yet effectively no one lives there. Consider the lights of Perth and Adelaide (each about 1M people) and Melbourne (4-5M) all outshone by a ton of places in Western Australia and Northern Territories. Something must be wrong there - is this map really made of photos, or some sort of "CGI" effect that got screwed up?

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 6:35 am
by Lar Gand
My question is this, why does there appear to be less light than in the April 2002 and October 2008 views that are supposed to be showing the same information?

Australian wildfires.

Posted: Fri Dec 07, 2012 7:09 am
by neufer
Click to play embedded YouTube video.
DougK wrote:
I am intreged as to the origin of the huge number of lights in the central part of Western Australia and parts of South Australia and Northern Territory. These are either clearly anomolies or the spinifex faries must have been having a party.
mstabb wrote:
The outback of Australia is brighter than the rest of the country - yet effectively no one lives there. Consider the lights of Perth and Adelaide (each about 1M people) and Melbourne (4-5M) all outshone by a ton of places in Western Australia and Northern Territories. Something must be wrong there - is this map really made of photos, or some sort of "CGI" effect that got screwed up?

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 7:11 am
by Ann
The EU may be in crisis, but it sure glitters.

Ann

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 7:15 am
by Biggles
mstabb wrote:The outback of Australia is brighter than the rest of the country - yet effectively no one lives there. Consider the lights of Perth and Adelaide (each about 1M people) and Melbourne (4-5M) all outshone by a ton of places in Western Australia and Northern Territories. Something must be wrong there - is this map really made of photos, or some sort of "CGI" effect that got screwed up?
Agreed. I fly over this region often at 39,000 feet as a long haul pilot. The number of ground lights, once you cross the coast near Port Headland, and head inland is effectively nil. Something not right here.

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 7:45 am
by paul_adams777
Biggles wrote:
mstabb wrote:The outback of Australia is brighter than the rest of the country - yet effectively no one lives there. Consider the lights of Perth and Adelaide (each about 1M people) and Melbourne (4-5M) all outshone by a ton of places in Western Australia and Northern Territories. Something must be wrong there - is this map really made of photos, or some sort of "CGI" effect that got screwed up?
Agreed. I fly over this region often at 39,000 feet as a long haul pilot. The number of ground lights, once you cross the coast near Port Headland, and head inland is effectively nil. Something not right here.
Agreed further. There is a further suspicious part about Western Australia - the vast majority of Western Australia's population is in the South West corner of the state. However, apart from Perth, there is no light showing in this area at all. :shock:

A similar oddness exists about the North East corner of Queensland. There is a large number of fairly substantial towns along the coast here, but very few lights show here.

The "greater sensitivity" seems to have resulted in a huge number of areas lighting up that are unpopulated and not lighting up that are well populated. :|

Please tell us that this was actually a joke.

Or, perhaps all the aliens who are going to cause the world to end on December 21 are living in the outback of Western Australia ? ? ?

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 10:06 am
by TechNoCaveMan
Sorry old chaps, there is something wrong with this picture. Western Australia has far to many lights on in the middle of the outback. There should be much fewer lights compared to the Easr Australian cost line. :ssmile:

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 10:22 am
by nujjer
Different subject:

The Mercator projection winds me up! I'm a Brit, and I always feel uneasy every time I see a map like this that shows lil' ol' England as much bigger than, say Florida, which has almost exactly the same area. Compare also the UK to India, which has about 12x the land area, and the idea of colonialism is difficult to put aside. Methinks Mercator (a Belgian, same latitude as the UK) was a self-publicist!

C'mon Florida, lets see a Floridator Projection!

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 10:32 am
by Agemegos
There's something bizarre going on in the picture of the western half of Australia. The photo shows a dense pattern of lights in the Great Sandy, Gibson, and Victoria deserts. Google Maps will confirm for you that those areas are utterly desolate.

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 10:47 am
by alanb
Great Photo! However I cannot work out why there are so many lights in the west and centre of Australia. In the large state of Western Australia, by far the largest city is Perth, which appears in the south west corner of the continent. All other lit areas in Western Australia & the Northen Territory (east of WA in the north) should have much less intensity of light than Perth. Perth's light is consistent with the other state capitals, Sydney. Melbourne and Brisbane on the east coast. Alan Byleveld

Re: Australian wildfires.

Posted: Fri Dec 07, 2012 11:08 am
by Ele6
For those who can't see the video above neufer posted, nor noticed the subject, the answer to the lights in Western Australia: wild fires.

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 12:35 pm
by neufer
nujjer wrote:
The Mercator projection winds me up! I'm a Brit, and I always feel uneasy every time I see a map like this that shows lil' ol' England as much bigger than, say Florida, which has almost exactly the same area. Compare also the UK to India, which has about 12x the land area, and the idea of colonialism is difficult to put aside. Methinks Mercator (a Belgian, same latitude as the UK) was a self-publicist!

C'mon Florida, lets see a Floridator Projection!
But lil' ol' England is preggers.

Re: Australian wildfires.

Posted: Fri Dec 07, 2012 1:34 pm
by strangeghost
Ele6 wrote:For those who can't see the video above neufer posted, nor noticed the subject, the answer to the lights in Western Australia: wild fires.
I don't think wild fires can be the explanation for the Australian lights. Don't wild fires usually have a signature crescent shape?

The western Australia anomaly was the first thing that caught my eye when I saw this image a few days ago. I'm glad to see other APODers on the ball too.

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 2:04 pm
by scr33d
this almost looks more like a 2-d histogram of light dots based on population density than an image composite.
almost every 'light pixel' have no variation in size, color or intensity.
how much and what kind of post-processing has been done?

edit: found the source image from NOAA: the 6 MB image explains away most of the above.

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 2:12 pm
by Psnarf
Two words: Light Pollution!

No wonder I can't see more than half a dozen stars from my backyard.

[Campfires of Australian Indigenous tribal gatherings? Folks thereabouts would make nice meals if they slept in the dark.]

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 2:46 pm
by Tory
One of the first things that jumped out at me were the new batches of lights in western North Dakota and in a crescent south of San Antonio, TX: oil and gas shale fields that have just been developed in the last few years. They almost look like giant cities! Maybe this is what's going on in western Australia too - some sort of mining operations?

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 2:55 pm
by tekic545
This is a beautiful image of wasted energy, notably from standard streetlights designed to achieve a broad beam, but in the process emitting 5% or more of their light upward. The International Darksky Association estimates in the U.S. alone, energy wasted in this manner costs $2.2 billion.

Next time you fly into a city at night, ask yourself why you can look down and see individual streetlights.

Bob Gillette

Evidence for advanced civilizations on planets

Posted: Fri Dec 07, 2012 2:59 pm
by neufer
Click to play embedded YouTube video.
Click to play embedded YouTube video.

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 3:18 pm
by test
south vs north korea is hilarious

Re: APOD: Earth at Night (2012 Dec 07)

Posted: Fri Dec 07, 2012 3:51 pm
by Chris Peterson
test wrote:south vs north korea is hilarious
Unless you have the misfortune of being a North Korean...