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APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 4:07 am
by APOD Robot
Image Clouds and Crosses over Haleakala

Explanation: Aloha and welcome to a breathtaking skyscape. The dreamlike panoramic view from March 27 looks out over the 10,000 foot summit of Haleakala on Maui, Hawai'i. A cloud layer seeps over the volcanic caldera's edge with the Milky Way and starry night sky above. Head of the Northern Cross asterism, supergiant star Deneb lurks within the Milky Way's dust clouds and nebulae at the left. From there you can follow the arc of the Milky Way all the way to the stars of the more compact Southern Cross, just above the horizon at the far right. A yellowish Mars is right of center, near the top of the frame, with rival red giant Antares below it, closer to the Milky Way's central bulge. Need some help identifying the stars? Just slide your cursor over the picture, or download this labeled panorama.

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Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 5:56 am
by revloren
I'm trying to figure out which direction this photo was taken. The Southern Cross on the right indicates that this was shot to the east. But there is very little development on the SE side of Maui to account for the city lights shining through the clouds in that direction.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 6:05 am
by Ann
I can't help you on that one, revloren. But I'd like to point out that the bright light at about one o'clock is Saturn.

Beautiful picture. Wally Pacholka always produces wonderfully photogenic images.

Ann

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 6:22 am
by FLPhotoCatcher
Somehow this looks like a composite of two photos - the sky and the ground, with the sky more distorted or 'compressed' than the ground.
I may be wrong of course, and it's a great photo regardless.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 6:29 am
by geckzilla
revloren wrote:I'm trying to figure out which direction this photo was taken. The Southern Cross on the right indicates that this was shot to the east. But there is very little development on the SE side of Maui to account for the city lights shining through the clouds in that direction.
Center of the image is approximately east. The place where the Milky Way touches the horizon at the right side of the image is approximately south. North is a little off the frame left of image. I simulated the conditions in Stellarium earlier tonight to see where the moon was. It's behind the clouds but I think it may have risen along with some early dawn light by the time he did the landscape portion of the panorama.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 6:38 am
by Nitpicker
revloren wrote:I'm trying to figure out which direction this photo was taken. The Southern Cross on the right indicates that this was shot to the east. But there is very little development on the SE side of Maui to account for the city lights shining through the clouds in that direction.
Crux is just west of south in this pic. The lights could be from the big island of Hawaii, maybe Waimea, to the SSE. (10,000 feet is pretty high.)

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 7:56 am
by superwillbee
Not mars but delta ophiuchi, right? And to the right of Antares we see Saturn...

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 8:27 am
by revloren
FLPhotoCatcher wrote:Somehow this looks like a composite of two photos - the sky and the ground, with the sky more distorted or 'compressed' than the ground.
I may be wrong of course, and it's a great photo regardless.
I was thinking that, but I believe that is a very typical cloud/sky pattern for the windward side of those ocean volcanoes.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 8:42 am
by revloren
Nitpicker wrote:Crux is just west of south in this pic. The lights could be from the big island of Hawaii, maybe Waimea, to the SSE. (10,000 feet is pretty high.)
Correct-a-mundo. Those are lights from the Big Island across the Maui Channel.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 10:07 am
by Boomer12k
Think of the ADVENTURE, of going up there, and getting that picture.....must be breath taking...


:---[===] *

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 10:28 am
by neufer
http://en.wikipedia.org/wiki/Double_cross_%28betrayal%29#Double_cross wrote: Double cross is a phrase meaning to deceive by double-dealing.

The phrase originates from the use of the word cross in the sense of foul play; deliberate collusion to lose a contest of some kind.

It has also been suggested that the term was inspired by the practice of 18th-century British thief taker and criminal Jonathan Wild, who kept a ledger of his transactions and is said to have placed two crosses by the names of persons who had cheated him in some way.

More recently, the phrase was used to refer to either of two possible situations:
  • A competitor participating in the fix who has agreed to throw their game instead competes as usual, against the original intention of their collaborators - one "cross" against another.

    Two opposing parties are approached, urging them to throw the game and back the other. Both parties lose out, and the perpetrators benefit by backing a third, winning party.
This use has passed into common parlance, so that, for example, in World War II, British Military Intelligence used the Double Cross System to release captured Nazis back to Germany bearing false information.>>

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 1:50 pm
by Chris Peterson
Nitpicker wrote:
revloren wrote:I'm trying to figure out which direction this photo was taken. The Southern Cross on the right indicates that this was shot to the east. But there is very little development on the SE side of Maui to account for the city lights shining through the clouds in that direction.
Crux is just west of south in this pic. The lights could be from the big island of Hawaii, maybe Waimea, to the SSE. (10,000 feet is pretty high.)
I'd say it's the lights of the Kona coast on the Big Island.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 3:51 pm
by Joe Stieber
superwillbee wrote:Not mars but delta ophiuchi, right? And to the right of Antares we see Saturn...
You are correct, the "Mars" label is misapplied. It is indeed Delta Ophiuchi, a.k.a., Yed Prior, and just below it is Yed Posterior (Epsilon Oph). They are the visually distinctive pair of third magnitude stars, the "Yeds," which represent the hands of Ophiuchus holding Serpens the snake. Mars and Spica would be just outside the upper-right-hand corner of the frame.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 6:01 pm
by ta152h0
The star labeled " Vega " is the pulsar noted in APOD's previously, right ? And can Geminga be seen here ?

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 6:12 pm
by Chris Peterson
ta152h0 wrote:The star labeled " Vega " is the pulsar noted in APOD's previously, right ? And can Geminga be seen here ?
Vega is not a pulsar. And Geminga is way, way too dim to show in this image, even if it were in the field of view, which is is not.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sat Apr 12, 2014 9:27 pm
by ta152h0
I was thinking Vela pulsar, similar spelling.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sun Apr 13, 2014 1:01 am
by Nitpicker
Chris Peterson wrote:
Nitpicker wrote:
revloren wrote:I'm trying to figure out which direction this photo was taken. The Southern Cross on the right indicates that this was shot to the east. But there is very little development on the SE side of Maui to account for the city lights shining through the clouds in that direction.
Crux is just west of south in this pic. The lights could be from the big island of Hawaii, maybe Waimea, to the SSE. (10,000 feet is pretty high.)
I'd say it's the lights of the Kona coast on the Big Island.
Yes, you're probably right. The dimmer lights to left of the brigher lights appear closer, and might be from Upolu Point.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sun Apr 13, 2014 5:19 am
by WolfmanSF
The "crater" of Haleakala is actually an erosional feature, not a volcanic caldera.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sun Apr 13, 2014 5:40 am
by geckzilla
WolfmanSF wrote:The "crater" of Haleakala is actually an erosional feature, not a volcanic caldera.
Thanks, I emailed the editors on your behalf.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sun Apr 13, 2014 10:59 am
by DavidLeodis
In view of what is stated in some posts could someone please confirm or not that the labelled image is correctly labelled ('labeled' in US spelling :) ) and is it Saturn that is the very bright object towards the top right? Thanks.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sun Apr 13, 2014 12:12 pm
by Nitpicker
DavidLeodis wrote:In view of what is stated in some posts could someone please confirm or not that the labelled image is correctly labelled ('labeled' in US spelling :) ) and is it Saturn that is the very bright object towards the top right? Thanks.
Yed Prior (Delta Ophiuchi) has been label[l]ed Mars. Saturn is in frame and Mars is not. I can't seem to simulate the exact projection of this APOD, but here is what I got out of Stellarium (showing a wider field including Mars and Spica):
Simulation in Stellarium: Orange line is Galactic Equator, Green line is local Meridian.
Simulation in Stellarium: Orange line is Galactic Equator, Green line is local Meridian.

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sun Apr 13, 2014 2:11 pm
by Joe Stieber
DavidLeodis wrote:In view of what is stated in some posts could someone please confirm or not that the labelled image is correctly labelled ('labeled' in US spelling :) ) and is it Saturn that is the very bright object towards the top right? Thanks.
As a follow-up to my earlier post, here's a correctly labeled version of the picture...
Click to view full size image
Here's a larger version.

Nunki business

Posted: Sun Apr 13, 2014 2:47 pm
by neufer
Joe Stieber wrote:
As a follow-up to my earlier post, here's
a correctly labeled version of the picture...
http://en.wikipedia.org/wiki/Sigma_Sagittarii wrote:
<<Sigma Sagittarii (Sigma Sgr, σ Sagittarii, σ Sgr) is the second brightest star in the constellation Sagittarius. Its modern name Nunki is an Assyrian or Babylonian name recovered by archaeologists and made public by R. H. Allen. Nunki is a B-type main sequence star with an apparent magnitude of +2.05. The distance to this star, determined using parallax measurements from the Hipparcos astrometry satellite,yields an estimated value of 70 parsecs from Earth.

The total luminosity of σ Sgr is 3300 times that of the Sun while it has a surface temperature of 18,890 K. X-ray emission has been detected from this star, which has an estimated X-ray luminosity of 1.2 × 1028 erg/s. Sigma Sgr has a magnitude +9.5 optical companion (Donna Rice :?: ) located 5.2 arcminutes away.

Because it is close to the ecliptic, Nunki can be occulted by the Moon and very rarely by planets. The last occultation of Nunki by a planet took place on November 17, 1981, when it was occulted by Venus. Furthermore, Nunki is the brightest star that can be principally occulted by an exterior planet. However, only Mars can do this, and only rarely; the last time was on September 3, 423.>>

Re: APOD: Clouds and Crosses over Haleakala (2014 Apr 12)

Posted: Sun Apr 13, 2014 6:32 pm
by Joe Stieber
A larger version of the IAU/Sky & Telescope chart of Sagittarius is available at:
http://www.iau.org/static/public/conste ... if/SGR.gif

You may need to click on the chart to get the full size.

Charts for all the constellations are linked on this IAU page (scroll down):
http://www.iau.org/public/themes/constellations/

In addition to links for the GIF format, links for PDF versions are provided too.