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APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 4:25 am
by APOD Robot
Image Five Planets and the Moon over Australia

Explanation: It is not a coincidence that planets line up. That's because all of the planets orbit the Sun in (nearly) a single sheet called the plane of the ecliptic. When viewed from inside that plane -- as Earth dwellers are likely to do -- the planets all appear confined to a single band. It is a coincidence, though, when several of the brightest planets all appear in nearly the same direction. Such a coincidence was captured just last week. Featured above, six planets and Earth's Moon were all imaged together last week, just before sunset, from Mornington Peninsula in Victoria, Australia. A second band is visible across the top of this tall image -- the central band of our Milky Way Galaxy.

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Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 6:06 am
by RocketRon
Great photo - and not so easy to achieve. ?

I'm wondering if a small component of APOD should be devoted to what camera equipment is used to capture such images.
??

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 7:10 am
by Nitpicker
Nice image. There must have been a few minutes between frames here (I'd guess 2 or 3 frames with something like an 18mm lens), as on 2016-08-08, Mercury was slightly closer to Venus in the sky, and a bit to the left. And Leo's tail (to the right of Mercury) is not as close to a right-angled triangle as it normally is. (Nitpicking, I know, sorry.) Note that the sky's zenith is a bit below and to the left of Mars.

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 11:24 am
by terrastro
Nitpicker wrote:Nice image. There must have been a few minutes between frames here (I'd guess 2 or 3 frames with something like an 18mm lens), as on 2016-08-08, Mercury was slightly closer to Venus in the sky, and a bit to the left. And Leo's tail (to the right of Mercury) is not as close to a right-angled triangle as it normally is. (Nitpicking, I know, sorry.) Note that the sky's zenith is a bit below and to the left of Mars.
Thanks for pointing it out. I checked and indeed the mosaic panel with Venus was slightly displaced in stitching software (PTGUI) plus the cylindrical projection made it more pronounced.

Regards,
Alex

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 3:45 pm
by Skytrainii
Sorry, I also have to nitpick. This image should be called Six Planets and The Moon because I can see six planets (the Earth as well).

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 3:46 pm
by Coil_Smoke
Is this image looking East ( Sunrise ) or looking West (Sunset) ? I'm trying to figure out which direction is 'Solar System North' or 'Above' the ecliptic is this fine photo ...

Re: APOD: Human as Spaceship (2016 Aug 15)

Posted: Tue Aug 16, 2016 5:19 pm
by DNDNDN
BTW, The red star next to Mars is Antares.

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 5:49 pm
by ta152h0
other than avoiding brown snakes, bice place to observe the sky

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 7:14 pm
by Coil_Smoke
Coil_Smoke wrote:Is this image looking East ( Sunrise ) or looking West (Sunset) ? I'm trying to figure out which direction is 'Solar System North' or 'Above' the ecliptic is this fine photo ...
Answering my own question and positing another ... I had a look at Stellarium And figure this image is a sunset looking West. It is remarkable how vertical the ecliptic appears from "Down Under" . it sure looks different from Mid Atlantic coast USA. Funny thing is, Mars looks 'South' of the ecliptic compared to the other visible planets. Is that even possible? :?:

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 10:12 pm
by Boomer12k
Spectacular!!!

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Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 10:17 pm
by Nitpicker
Skytrainii wrote:Sorry, I also have to nitpick. This image should be called Six Planets and The Moon because I can see six planets (the Earth as well).
But you cannot see six planets over Australia (the air above Australia is also Australia.)

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Tue Aug 16, 2016 10:58 pm
by Nitpicker
Coil_Smoke wrote:
Coil_Smoke wrote:Is this image looking East ( Sunrise ) or looking West (Sunset) ? I'm trying to figure out which direction is 'Solar System North' or 'Above' the ecliptic is this fine photo ...
Answering my own question and positing another ... I had a look at Stellarium And figure this image is a sunset looking West. It is remarkable how vertical the ecliptic appears from "Down Under" . it sure looks different from Mid Atlantic coast USA. Funny thing is, Mars looks 'South' of the ecliptic compared to the other visible planets. Is that even possible? :?:
Mars is indeed a little south of the ecliptic at the moment. The ecliptic plane is defined by the Sun-Earth system. It is only an approximation of the orbital plane of the other planets.

Half the ecliptic is in the northern sky and half in the southern. The closer you are to the Earth's equator, the more vertical the ecliptic can appear relative to the horizon (at the right time of day/year). It can't be perfectly vertical unless you are in the tropics.

Being winter down here, the Sun is low in the sky in the short days, and the planets are high in the sky in the long nights. The same thing happens in the northern winter. Winter is typically better for observing the planets, weather notwithstanding.

In this APOD, taken from well south of the tropics, the ecliptic appears more vertical than it is, because of the projection.

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Wed Aug 17, 2016 11:42 am
by Rusty Brown in Cda
"...In this APOD, taken from well south of the tropics, the ecliptic appears more vertical than it is, because of the projection."

That addresses the question in my mind as to how the planets can be almost vertical to the horizon that far from the equator. Here on the north shore of Lake Ontario in Canada, the sun and planets always rise and set towards the right, and are never anywhere close to vertical.

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Wed Aug 17, 2016 12:07 pm
by Guest
Opps, someone cannot count. There are only 'five' planets and the Earth's moon sited on the photograph. The paragraph text (not label) indicated 'six' planets.

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Wed Aug 17, 2016 1:34 pm
by geckzilla
Guest wrote:Opps, someone cannot count. There are only 'five' planets and the Earth's moon sited on the photograph. The paragraph text (not label) indicated 'six' planets.
The sixth is Earth.

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Thu Aug 18, 2016 12:08 pm
by Guest
If that were the case, then the caption is wrong and should indicate "six". You cannot have it both ways.

Re: APOD: Five Planets and the Moon over Australia (2016 Aug 16)

Posted: Thu Aug 18, 2016 12:12 pm
by geckzilla
Guest wrote:If that were the case, then the caption is wrong and should indicate "six". You cannot have it both ways.
It does mention six. The title says five over. Without the over qualifier, there are six.