Comments and questions about the
APOD on the main view screen.
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APOD Robot
- Otto Posterman
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by APOD Robot » Thu Sep 01, 2016 4:06 am
Light at the End of the Road
Explanation: The bright light at the end of this country road is actually a remarkably
close conjunction of two planets. After sunset on August 27 brilliant Venus and
Jupiter almost appear as a single celestial beacon in the
night skyscape taken near Lake Wivenhoe, Queensland, Australia. A spectacular vertical panorama from the
southern hemisphere, it shows the central Milky Way near zenith, posed on top of a pillar of Zodiacal light along the ecliptic plane. Of course Mars and Saturn are
near the ecliptic too, just below the galaxy's central bulge. Above and left of a tree on the horizon, fleeting planet Mercury also adds to the light at the
end of the road.
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FLPhotoCatcher
- Science Officer
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by FLPhotoCatcher » Thu Sep 01, 2016 7:13 am
It looks like the ecliptic is around 60 degrees off the plane of the Milky Way. How unusual is that, knowing what we do about other 'solar' systems?
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neufer
- Vacationer at Tralfamadore
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by neufer » Thu Sep 01, 2016 9:26 am
Like Neil deGrasse Tyson, I too was deeply impressed by my first trip to a Zeiss Planetarium at the age of nine. On December 1955, my father drove me south from Alexandria, Virginia, in our old black Plymouth on a special trip to the then new Morehead Planetarium in Chapel Hill, North Carolina. It happened to be Morehead's traditional XMAS program where they demonstrated how the
Star of Bethlehem might have been a close conjunction between Jupiter and Venus (near Regulus) on June 17, 2 BC. However, "
since the conjunction would have been seen in the west at sunset [as in today's APOD]
it could not have led the magi south from Jerusalem to Bethlehem."
http://voices.nationalgeographic.com/2011/12/26/searching-for-the-star-of-bethlehem/ wrote:
Searching for the Star of Bethlehem
Posted by rjvanderbei of Princeton University
<<A popular explanation for the Star of Bethlehem is that it was actually a conjunction of Jupiter and Venus that presumably occurred on June 17, 2BC. The modern version of JPL’s numerical integrator is known as DE406. DE406 is the ultimate modern tool for validating the earlier claims. Using the web interface, I downloaded positional information for Venus and Jupiter on June 17, 2BC. According to DE406, the conjunction on June 17, 2BC had a minimal separation of 26.2 arcseconds [vs. ~4 arc minutes for today's APOD].>>
https://en.wikipedia.org/wiki/Morehead_Planetarium_and_Science_Center wrote:
<<Morehead Planetarium opened on May 10, 1949 on the campus of the University of North Carolina at Chapel Hill. The first planetarium in the South, it was only the sixth to be built in the United States. Designed by the same architects who planned the Jefferson Memorial, the cost of its construction, more than $23,000,000 in today’s dollars, made it the most expensive building ever built in North Carolina at the time. It is one of the oldest and largest planetariums in the United States having welcomed over 7 million visitors by its 60th anniversary in 2009.
Since Zeiss, the German firm that produced planetarium projectors, had lost most of its factories during World War II, there were very few projectors available at the time. John Motley Morehead III had to travel to Sweden, where he had previously served as American ambassador, to purchase a Zeiss Model II to serve as the heart of North Carolina’s new planetarium.
From 1959 through 1975 every astronaut in the Mercury, Gemini, Apollo, Skylab, and Apollo-Soyuz Test Project programs spent hours in celestial navigation training at the planetarium. Morehead technicians developed simplified replicas of flight modules and tools for use in the training, often from plywood or cardboard. A mockup simulating key parts of the Gemini capsule was constructed from plywood and mounted on a barber chair to enable changes in pitch and yaw. Several of these items are on display at the planetarium. That training may have helped save astronauts' lives on occasion. Astronauts aboard Apollo 12 called upon that training after their Saturn V rocket was hit by lightning twice during ascent, knocking spacecraft systems offline and requiring them to configure navigation systems based on fixes taken manually. Gordon Cooper used his training to make the most accurate landing of Project Mercury after a power failure affected navigational systems. Astronauts enjoyed soft drinks, cookies and other snacks during their intense hours-long training session, leading planetarium employees to create the code name "cookie time" to refer to the training sessions.
The first astronaut to train at Morehead, in March 1964, was Neil A. Armstrong. Armstrong visited again only months before the 1969 launch of Apollo 11, spending a total of 20 days at Morehead over 11 training sessions, more than any other astronaut. Astronauts commented that the "large dome" was "highly realistic" calling the facility "superb".>>
Art Neuendorffer
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Chris Peterson
- Abominable Snowman
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by Chris Peterson » Thu Sep 01, 2016 10:24 am
FLPhotoCatcher wrote:It looks like the ecliptic is around 60 degrees off the plane of the Milky Way. How unusual is that, knowing what we do about other 'solar' systems?
The relationship between the spin axis of a stellar system and the galactic plane is essentially random. So there's nothing unusual at all about the orientation of our system, or any other.
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paulslittlebit
- Ensign
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by paulslittlebit » Thu Sep 01, 2016 11:41 am
FLPhotoCatcher wrote:It looks like the ecliptic is around 60 degrees off the plane of the Milky Way. How unusual is that, knowing what we do about other 'solar' systems?
According to Christopher Springob PhD in a blog named "Ask an Astronomer" at
http://curious.astro.cornell.edu/about- ... termediate, "They're
(solar system) oriented in all different directions. The size of a solar system is so much smaller than the size of the Galaxy, that the Galaxy's structure has no impact on the orientation of a solar system. What determines their orientations is the direction of the angular momentum that the system had when it formed, and that's pretty much random."
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hamilton1
- Ensign
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by hamilton1 » Thu Sep 01, 2016 1:24 pm
neufer wrote:It happened to be Morehead's traditional XMAS program where they demonstrated how the
Star of Bethlehem might have been a close conjunction between Jupiter and Venus (near Regulus) on June 17, 2 BC. However, "
since the conjunction would have been seen in the west at sunset [as in today's APOD]
it could not have led the magi south from Jerusalem to Bethlehem."
It is pretty remarkable that the most favourable conjunction of the two brightest planets during the last 2000 years occurred over the Middle East in 2 BC. All other Venus/Jupiter conjunctions in the intervening years were at lesser solar elongation and from different locations. But the Wise Men would not have been very wise if they'd confused two famous planets with a 'star'.
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heehaw
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by heehaw » Thu Sep 01, 2016 1:59 pm
A beautiful picture of our Galaxy! A thousand years ago, or ten thousand years ago, with no street lights, the human eye saw the Galaxy about as well as we see it in this photo (but with no color; rods-and-cones stuff). We have the extraordinary privilege of seeing it (only on the computer now, except for those folks in the Outback) with understanding. What a joy!
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neufer
- Vacationer at Tralfamadore
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- Location: Alexandria, Virginia
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by neufer » Thu Sep 01, 2016 2:00 pm
hamilton1 wrote:neufer wrote:
It happened to be Morehead's traditional XMAS program where they demonstrated how the
Star of Bethlehem might have been a close conjunction between Jupiter and Venus (near Regulus) on June 17, 2 BC. However, "
since the conjunction would have been seen in the west at sunset [as in today's APOD]
it could not have led the magi south from Jerusalem to Bethlehem."
It is pretty remarkable that the most favourable conjunction of the two brightest planets during the last 2000 years occurred over the Middle East in 2 BC. All other Venus/Jupiter conjunctions in the intervening years were at lesser solar elongation and from different locations. But the Wise Men would not have been very wise if they'd confused two famous planets with a 'star'.
- Poetic license
The Wise Men would not have been very good astrologers
if they had simply ignored such an interesting conjunction due west of Babylon.
https://en.wikipedia.org/wiki/Euphemism wrote:
<<Euphemism comes from the Greek word εὐφημία (euphemia), meaning "the use of words of good omen", which in turn is derived from the Greek root-words eû (εὖ), "good, well" and phḗmē (φήμη) "prophetic speech; rumour, talk". Etymologically, the eupheme is the opposite of the blaspheme "evil-speaking." The term euphemism itself was used as a euphemism by the ancient Greeks, meaning "to keep a holy silence".>>
Art Neuendorffer
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equip
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by equip » Thu Sep 01, 2016 4:50 pm
First of all, I love your website! I view it frequently. However, I feel you are a bit too wordy in general, especially for those of us who aren't quite so up on astronomy.
I like it when you state where the picture/photo is taken, as you did in this latest image.
anyway, thank you!
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Chris Peterson
- Abominable Snowman
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by Chris Peterson » Thu Sep 01, 2016 5:10 pm
heehaw wrote:A beautiful picture of our Galaxy! A thousand years ago, or ten thousand years ago, with no street lights, the human eye saw the Galaxy about as well as we see it in this photo (but with no color; rods-and-cones stuff). We have the extraordinary privilege of seeing it (only on the computer now, except for those folks in the Outback) with understanding. What a joy!
Most people live within an hour or two of a location where they can see the Milky Way pretty much the same as our ancient ancestors did. Which is nowhere near as contrasty as this image shows, even without the color.
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Fred the Cat
- Theoretic Apothekitty
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- AKA: Ron
- Location: Eagle, Idaho
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by Fred the Cat » Thu Sep 01, 2016 5:26 pm
equip wrote:First of all, I love your website! I view it frequently. However, I feel you are a bit too wordy in general, especially for those of us who aren't quite so up on astronomy.
I like it when you state where the picture/photo is taken, as you did in this latest image.
anyway, thank you!
I also love the site but I also love the words. Otto, and with due respect to neufer, I do have to reply on your behalf, "
What, me wordy?'"
Freddy's Felicity "Only ascertain as a cat box survivor"
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Cygnus_d_swan
- Asternaut
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by Cygnus_d_swan » Thu Sep 01, 2016 8:58 pm
FLPhotoCatcher wrote:It looks like the ecliptic is around 60 degrees off the plane of the Milky Way. How unusual is that, knowing what we do about other 'solar' systems?
This appears to be a trick photo or combination of images. I take pictures of Milky Way from the west of Sydney. I have taken photos of conjuction of Venus and Jupiter as well.
The location where I take photos from is 3 degrees south of the location in Queensland where this photo was taken. At around 6:00PM to 7:00PM when Venus and Jupiter were visible on Horizon, Scorpius and Sagitarius are absolutely overhead and not so close to Horizon in the west. Besides, Scorpius sets closer to Southern Polar Region in south west and Venus and Jupiter set few degrees west of this location. While image is superb, what I can't seem to figure is, how come there is such big difference in sky between Sydney and just 3 degrees north of it in Qld?
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Chris Peterson
- Abominable Snowman
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by Chris Peterson » Thu Sep 01, 2016 9:26 pm
Cygnus_d_swan wrote:This appears to be a trick photo or combination of images. I take pictures of Milky Way from the west of Sydney. I have taken photos of conjuction of Venus and Jupiter as well.
The location where I take photos from is 3 degrees south of the location in Queensland where this photo was taken. At around 6:00PM to 7:00PM when Venus and Jupiter were visible on Horizon, Scorpius and Sagitarius are absolutely overhead and not so close to Horizon in the west. Besides, Scorpius sets closer to Southern Polar Region in south west and Venus and Jupiter set few degrees west of this location. While image is superb, what I can't seem to figure is, how come there is such big difference in sky between Sydney and just 3 degrees north of it in Qld?
Note that the little triad of Mars, Saturn, and Antares, below the Milky Way's brightest region, is only about 4° below/west of the zenith. The top of this image extends all the way over the zenith and some 45° back towards the eastern horizon. In other words, if you were looking at this sight with your eyes, the top of the image is halfway down the sky behind you. Scorpius and Sagittarius are, indeed, near the zenith in this image. These are the kinds of illusions you get when you flatten very wide fields onto a plane. To see this properly, you really need to view the image painted onto a sphere around you- just like the actual sky.
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Cygnus_d_swan
- Asternaut
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by Cygnus_d_swan » Thu Sep 01, 2016 10:56 pm
Chris Peterson wrote:Cygnus_d_swan wrote:This appears to be a trick photo or combination of images. I take pictures of Milky Way from the west of Sydney. I have taken photos of conjuction of Venus and Jupiter as well.
The location where I take photos from is 3 degrees south of the location in Queensland where this photo was taken. At around 6:00PM to 7:00PM when Venus and Jupiter were visible on Horizon, Scorpius and Sagitarius are absolutely overhead and not so close to Horizon in the west. Besides, Scorpius sets closer to Southern Polar Region in south west and Venus and Jupiter set few degrees west of this location. While image is superb, what I can't seem to figure is, how come there is such big difference in sky between Sydney and just 3 degrees north of it in Qld?
Note that the little triad of Mars, Saturn, and Antares, below the Milky Way's brightest region, is only about 4° below/west of the zenith. The top of this image extends all the way over the zenith and some 45° back towards the eastern horizon. In other words, if you were looking at this sight with your eyes, the top of the image is halfway down the sky behind you. Scorpius and Sagittarius are, indeed, near the zenith in this image. These are the kinds of illusions you get when you flatten very wide fields onto a plane. To see this properly, you really need to view the image painted onto a sphere around you- just like the actual sky.
Thanks for your reply. I figured that this had to be very widefield inage. I am novice at processing and take my photos with kit lenses. Minimum being 18mm. Would love to know what lense was used to take this image.
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Chris Peterson
- Abominable Snowman
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by Chris Peterson » Fri Sep 02, 2016 4:55 pm
Cygnus_d_swan wrote:Thanks for your reply. I figured that this had to be very widefield inage. I am novice at processing and take my photos with kit lenses. Minimum being 18mm. Would love to know what lense was used to take this image.
The image is a mosaic- a collection of 30-s exposures stitched together into a single vertical panorama. A 10mm focal length lens was used (equivalent to a 15mm lens with a full-frame sensor), but with a mosaic, the lens focal length doesn't determine the field-of-view, just the number of frames required to fill the field.