APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

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Expand view Topic review: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by DavidLeodis » Tue Mar 12, 2013 11:46 pm

Thanks again Chris. Your input is appreciated. :)

This is (well at least to me!) a very confusing APOD. :?

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Chris Peterson » Tue Mar 12, 2013 11:30 pm

DavidLeodis wrote:Having originally thought that the yellow strip below that red area was the glow of the street lights (but not appearing green) I then assumed that the short yellow bit further right is the exploding lava but I now think the lava may be the longer yellow strip beneath the red area where the Sun is rising. What the short yellow strip is I therefore do not know unless it is a small area of exploding lava.
The large area under the red is certainly the lights of Hilo. It's the only thing to the east, and there is no lava flowing near Hilo. The smaller yellow strip towards the right is almost certainly another town- there are several to the south with a few thousand residents, so that amount of light makes perfect sense. I'm skeptical that the light of any lava flows is visible in this image. If it is, it must be very subtle.

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by DavidLeodis » Tue Mar 12, 2013 8:11 pm

Thanks to all for your responses to my query. From them I now realise that the "eerie, greenish glow in the clouds" is likley to be the faint pale greenish to pinkish area in the clouds below the Northern Cross and beyond the cinder cones. It is so pale though (at least on my monitor) that I never even noticed it (until now) and thought with it being mentioned in the explanation it would be very obvious. In the image description in Wally Pacholka's website it states "The Milky Way is seen in the distance stretching across the sky above the beginnings of a sun rise (the red glow). The golden colored clouds are lit by the street lights of the city Hilo, and to the right the red glow through the clouds is lava exploding into the ocean", so the red area above the horizon near the centre is the rising Sun. Having originally thought that the yellow strip below that red area was the glow of the street lights (but not appearing green) I then assumed that the short yellow bit further right is the exploding lava but I now think the lava may be the longer yellow strip beneath the red area where the Sun is rising. What the short yellow strip is I therefore do not know unless it is a small area of exploding lava.

I hope that makes sense! I apologise if I have caused any confusion and that I should have worked all that out, but I find it odd that Wally Pacholka gave no mention of an "eerie, greenish glow" yet the explanation does and the latter also has no mention of the lava nor the rising Sun. :?

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Ann » Tue Mar 12, 2013 3:29 am

The way I understand the APOD caption, the traces of green are not found in the sky, but in the cloud deck "below" the sky.

I see a bit of yellow-green in the cloud tops directly below Epsilon Cygni (that's the star closest to the horizon in the Northern Cross in the annotated image). But this bit of green pales in comparison with the large yellow splash near center of the cloud tops, and in the small yellow streak at right.

The sky above the large yellow streak in the clouds is strikingly orange, whereas much of the sky along the rest of the horizon takes on a pinkish-brown tinge. At least on my screen.

Ann

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by rstevenson » Tue Mar 12, 2013 2:15 am

On my screen (also calibrated) the majority of the glow I see is pinky purple (sodium pink?) with a good splash of orange above the central yellow cloud-smear. I can find faint traces of green, mostly top-left with a tiny bit of it low in the sky to the right -- though I can only see those green bits using my color meter, because it expands each pixel to about a millimeter square.

Rob

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by DavidLeodis » Mon Mar 11, 2013 11:16 pm

Thanks Chris and Beyond for your responses to my query relating to some colours in the APOD image. :)

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Ron-Astro Pharmacist » Mon Mar 11, 2013 9:56 pm

From my memory Cygnus looks more rotated at this latitude(43.7 N) so the head of the Swan is pointed upward. The Southern Cross, in this photo, appears upright as it did in this APOD

http://apod.nasa.gov/apod/ap080707.html

taken from a position near the South Pole. I would expect a similarly rotated Southern Cross. Any reason why it's not?

I still have a hard time imagining it. As to say - Orion appears on its head in the southern hemisphere but upright in the north. If I stood on my head it might appear as it does south of the equator. Maybe a simulation of a well known constellation, changing as one rapidly moves from the northern hemisphere to the southern hemisphere would make a good APOD for people like me. Just don't ask me to do it.
:)

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Beyond » Mon Mar 11, 2013 9:23 pm

On my monitor, which i haven't touched since i got the computer, the lights of Hilo (just beyond the volcano cones) are a sort of yellowish tinged green. But just to the right, there's a bright yellow patch.

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Chris Peterson » Mon Mar 11, 2013 9:18 pm

DavidLeodis wrote:In the description of the photo in Wally Pacholka's website it was very interesting to read that the yellow glow (on my monitor, but said to be a red glow in the description) through the clouds to the right "is lava exploding into the ocean". Wow!

PS. In the APOD explanation it states "illumination from the city lights of Hilo creates an eerie, greenish glow in the clouds" but it is reddish, not greenish, on my monitor so I wonder if that is incorrectly set or does it not appear greenish to others?
On my monitor (which I keep calibrated) the lights of Hilo are distinctly sodium yellow, and the sky above that has a red cast. The lights of another town are to the right, also sodium yellow (I'd guess that's the town of volcano). And there is diffuse sodium glow to the northeast, presumably from the coastal towns north of Hilo. I see no red glow to the right at all; nothing to suggest the glow sometimes seen from lava.

That said, Pacholka's images are virtually always heavily processed (I'd say grotesquely so, but aesthetics are personal) and this image is no exception. In my opinion, the sky colors are moderately distorted, and it's hard to say what that processing has done with other light sources. The sodium lighting is distinctly shifted from yellow-orange to yellow, however.

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by DavidLeodis » Mon Mar 11, 2013 8:35 pm

In the description of the photo in Wally Pacholka's website it was very interesting to read that the yellow glow (on my monitor, but said to be a red glow in the description) through the clouds to the right "is lava exploding into the ocean". Wow!

PS. In the APOD explanation it states "illumination from the city lights of Hilo creates an eerie, greenish glow in the clouds" but it is reddish, not greenish, on my monitor so I wonder if that is incorrectly set or does it not appear greenish to others?

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Anthony Barreiro » Mon Mar 11, 2013 7:35 pm

Breathtaking, literally and metaphorically. 4200 meters elevation! It's even higher if you measure in feet!

At 20 degrees north latitude, Hawaii is an interesting place for skywatching. You see all the northern constellations, but the area of circumpolar stars is much smaller than at midnorthern latitudes. You can really see why Polynesians call the constellation of Scorpio Maui's fishhook, the one he used to pull the Hawaiian islands out of the sea. And you can see a lot of the southern constellations. I've only been to Hawaii once, but I want to go back!

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Bob » Sun Mar 10, 2013 10:06 pm

Chris - You're right. I had looked at several of Pacholka's images on his website in the past, and the claim he made for those images was that they were single, unedited exposures. In this case, I assumed, and did not check, that he made the same statement, but in fact he did not. I just had a look at his website and in this case he was clear this was stitched from several photos. I owe him an apology in this case; the geometry is possible (I also looked at the summit in Google Earth, and given it's a stitched panorama I came to the same conclusion you did). It doesn't change my opinion of a lot of his other stuff, but I retract the statement that you responded to. Thanks for forcing me to take a closer look .

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Chris Peterson » Sun Mar 10, 2013 9:25 pm

Bob wrote:Suggestion: go to the Institute for Astronomy, Univ. of Hawaii webpage and download the pdf map of the summit of Mauna Kea. Note the direction of north (the arrow at bottom center in the pdf). Note also the positions of the CFHT and Gemini North domes at the right part of the map. Look at the panorama, and realize that from the position of the camera (which is aimed roughly southeast), only part of the CFHT dome is visible. Then ask yourself, how could the background possibly include Polaris, which is within one degree of true north? From the position of the camera, Polaris is either behind the CFHT dome or would appear to the left of the dome. This is a nice photomontage, made up of two separate images and combined. It is not real. Many if not all of Pacholka's images are similar photomontages. They're well done, pretty, and interesting, and if he was up front that they are constructions, that would be fine. But he claims they are real, single exposures. If you look at the geometry of the summit, the domes, and the sky, it is physically impossible for this to be one exposure. Yet people continue to be taken in. People who should know better.
There's nothing impossible about it at all. You stand a bit southeast of the CFHT dome and start your exposure north, sweeping the panorama clockwise to the east (over Hilo) and ending up pointing a little west of south, just past the Gemini dome. There may or may not be images combined here to create a mosaic, or to manage different light levels, but there's certainly nothing physically out of place with this panorama. The sky background is completely consistent with the dome positions.

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Bob » Sun Mar 10, 2013 8:39 pm

Suggestion: go to the Institute for Astronomy, Univ. of Hawaii webpage and download the pdf map of the summit of Mauna Kea. Note the direction of north (the arrow at bottom center in the pdf). Note also the positions of the CFHT and Gemini North domes at the right part of the map. Look at the panorama, and realize that from the position of the camera (which is aimed roughly southeast), only part of the CFHT dome is visible. Then ask yourself, how could the background possibly include Polaris, which is within one degree of true north? From the position of the camera, Polaris is either behind the CFHT dome or would appear to the left of the dome. This is a nice photomontage, made up of two separate images and combined. It is not real. Many if not all of Pacholka's images are similar photomontages. They're well done, pretty, and interesting, and if he was up front that they are constructions, that would be fine. But he claims they are real, single exposures. If you look at the geometry of the summit, the domes, and the sky, it is physically impossible for this to be one exposure. Yet people continue to be taken in. People who should know better.

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Chris Peterson » Sun Mar 10, 2013 8:12 pm

Czerno -1 wrote: - what is the /average/ height of emerged land (above sea level) ?
- what is the /average/ depth of ocean floor (below sea level, duh) ?
- what is the average level of (both emerged and drowned) the Earth surface, relative to average sea level ?
Google is your friend.

Mean height of land area: 840 m
Mean depth of ocean area: 3682 m
Average ocean depth if the surface were spherical: 2800 m

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Czerno -1 » Sun Mar 10, 2013 6:26 pm

BDanielMayfield wrote:
greatguyinsf wrote:1st of all - Wow.
2ndly - They get snow in Hawaii?
Up on 4200 meter Mauna Kea, sure. Measured from it's base where it rises from the sea-floor it's the world's tallest mountain.
Ah! I may dare piggy-back a compound question here, which coïncidentally I was wondering about just this morning. Not an astronomical question to be sure, rather one of geography.

- what is the /average/ height of emerged land (above sea level) ?
- what is the /average/ depth of ocean floor (below sea level, duh) ?
- what is the average level of (both emerged and drowned) the Earth surface, relative to average sea level ?

Hope I'll be pardonned the off-topic...

--
Czerno

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Ann » Sun Mar 10, 2013 5:40 pm

Earth explodes, eh?
And here I thought the people at DC Comics exaggerated when they insisted that Superman's home planet Krypton had exploded....

So what Earth baby will be the lucky survivor, being shuttled away from the Earth in a, well, space shuttle, on his way to Supermanhood on another planet?

Ann

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Moonlady » Sun Mar 10, 2013 1:08 pm

Dear amazing APOD team,

I am concerned about tomorrow!!! :ohno:

How does you incredible team informed us average people only one day before the EARTH EXPLODES!!! :shock:


I already sold my 2012 Dec World End protection utensils like my tinfoil hat! :cowboy:

Now I have to go to the grocery to buy aluminium foil, but what?! It's sunday and I can't!!!

I even dont have :doughnut: and :b: to go with it, at home to sit back and enjoy the show!!!

Have mercy next time please when the world ends. :derp:

sincerely

PS: I assume it's gonna be Etna? :D

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by BDanielMayfield » Sun Mar 10, 2013 12:49 pm

greatguyinsf wrote:1st of all - Wow.
2ndly - They get snow in Hawaii?
Up on 4200 meter Mauna Kea, sure. Measured from it's base where it rises from the sea-floor it's the world's tallest mountain.

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by BDanielMayfield » Sun Mar 10, 2013 12:30 pm

owlice wrote:
Q4: Have some APOD pictures been run more than once?
A4: Yes. Many of our readers have been with us less than a year and are unaware of some really spectacular or important astronomy pictures. New information about old pictures is becoming available over the WWW. The text and links for rerun pictures will make use of this newly available information. So although the picture might be old, some of the text and links of each APOD will be new. Also, more web surfers have larger bandwidth connections, which allows us to post higher-resolution image files that can be transferred conveniently. Software to handle more sophisticated image file formats has also become more common, so the picture's size and/or format might be new. Lastly, rerunning APODs saves us time and helps us update our archive. In general, our rerun policy currently is to only rerun APODs more than one year old to keep the pictures relatively "new" to new APOD viewers. We will almost never rerun more than two pictures in any given week. So when you load the current APOD,it is still, most probably, a new picture.
http://apod.nasa.gov/apod/ap_faq.html

It would be unkind, I suppose, to point out that the complaint about a repeated APOD has been seen before (many times), so I won't...
This answer fits me rather well. Thanks for the rerun, and it's so stunning I won't mind seeing it again in years to come. (Err, unless the world happens to end first. See Moonlady's comment two posts down.)

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by greatguyinsf » Sun Mar 10, 2013 11:00 am

1st of all - Wow.
2ndly - They get snow in Hawaii?

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Karma » Sun Mar 10, 2013 10:59 am

To tell the truth, APOD has never been failed to shock me. The panorama today, regardless of my disability to connect the "Northern Cross" to "Cygnus", is spectacular too. Hope I can go to some places like Hawaii to see the scene someday.

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by MargaritaMc » Sun Mar 10, 2013 9:53 am

This is an absolutely stunning image! To be able to see Polaris and the Southern Cross in the same photograph :shock: :!:
I've only been visiting this site for about two months and, although I DO browse through the Apod archives, I am always very glad when some are brought to my attention. As in today's image.

Margarita

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Boomer12k » Sun Mar 10, 2013 9:10 am

Ah, the Milky Way. The Pipe Nebula, the Dragon Fly just above the Pipe, maybe carrying it, The guy doing PUSH UPS to the right of that, and in the far left, the Head of the Dragon heading down into the clouds, with Deneb and the Northern Cross. Always a pleasure!!!!

:---[===] *

Still too cold here to get out and do anything, but I am going to try earlier in the evening.

Re: APOD: Milky Way Panorama from Mauna Kea (2013 Mar 10)

by Ann » Sun Mar 10, 2013 7:30 am

I like the picture! Lots of stars, constellations and nebulae show up really well. It's nice that the picture is annotated. For myself, I love the blue brilliance of Vega. When I used to belong to an astronomy club and we showed stars to visitors, I always asked them to look at Vega and say what color it seemed to be. Everyone said it looked bluish!

As for the fact that this is a repeat picture, well, Sundays are the repeat days at APOD. Those who choose the pictures to be published, write the captions and provide numerous links to go with the pictures need a day off, too!

Ann

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