Explanation: The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the red emission nebula in the center of the above photograph. The horse-head feature is dark because it is really an opaque dust cloud that lies in front of the bright red emission nebula. Like clouds in Earth's atmosphere, this cosmic cloud has assumed a recognizable shape by chance. After many thousands of years, the internal motions of the cloud will surely alter its appearance. The emission nebula's red color is caused by electrons recombining with protons to form hydrogen atoms. On the image left is the Flame Nebula, an orange-tinged nebula that also contains filaments of dark dust. Just to the lower left of the Horsehead nebula featured picture is a blueish reflection nebulae that preferentially reflects the blue light from nearby stars.
That's another fine picture of the Horsehead and Flame Nebula region.
Interestingly, there is a very flame-like nebula in this picture, but it's not the Flame Nebula itself. It is rather the red emission nebula behind the Horsehead. I have never seen this nebula take on such a smoldering, orange-red hue.
Bring out the fire extinguisher! (And I mean that as praise. The fiery red nebula adds a lot of power and energy to the image, particularly since the rest of the picture isn't red.)
Ann
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Wed Dec 16, 2015 5:40 am
by Nitpicker
According to my (rusty and unchecked) calculations, the neck of the horse is less than three light years across. One might even be able to detect slight changes in shape over a few decades, if one didn't feel like waiting many millennia.
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Wed Dec 16, 2015 5:50 am
by Chris Peterson
Once again, it isn't a horse's head...
hh-ass.jpg (19.54 KiB) Viewed 11515 times
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Wed Dec 16, 2015 6:46 am
by Nitpicker
Yes, but the backside and tail don't make me think "horse", when I see it. 'Tis the head, Sir!
(Bloody horse people!)
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Wed Dec 16, 2015 8:59 am
by DL MARTIN
once i lock on to the rear view of the horse, it's hard to see it any other way.
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Wed Dec 16, 2015 11:08 am
by neufer
Chris Peterson wrote:
Once again, it isn't a horse's head...
I wonder exactly where Slartibartfast lives then
https://en.wikipedia.org/wiki/Places_in_The_Hitchhiker's_Guide_to_the_Galaxy#Magrathea wrote:
<<Magrathea is an ancient planet located in orbit around the twin suns Soulianis and Rahm in the heart of the Horsehead Nebula. Magrathea is a planet whose economy was based on the manufacturing of other planets for the wealthiest people in the universe. It was the people of Magrathea (known as "Magratheans"), and including Slartibartfast, who created the Earth.
Magrathea is considered the home of the industry of "Custom-made luxury planet building." It was a market aimed at the richest of the rich, during the days of the former Galactic Empire. The Magratheans would design and create entire planets for wealthy clients. They were so successful that Magrathea became the richest planet of all time. However, this resulted in the rest of the galaxy being plunged into abject poverty and the economy collapsing. The planet then faded from memory with most people believing it to be just a myth.
Amongst the clients who asked for planets to be created were a race of hyper-intelligent pan-dimensional beings who asked the Magratheans to create the Earth which, in addition to being a planet, was a super-computer designed to calculate the ultimate question to the ultimate answer to life, the universe, and everything. Amongst the people who worked on it was Slartibartfast, a coastal designer who won an award for his work on Norway's fjords.
The surface of the planet appears to be dead, described as "blighted", with the Magratheans kept in cryogenic sleep within the planet, not to be awakened until the economy was again strong enough to afford luxury planets. The book says that, "Bits of it were dullish grey, bits of it dullish brown, the rest of it rather less interesting to look at. It was like a dried-out marsh, now barren of all vegetation and covered with a layer of dust about an inch thick. It was very cold." They were later awakened for the reconstruction of the Earth (the Earth, Mk. II).>>
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Wed Dec 16, 2015 4:44 pm
by Ron-Astro Pharmacist
With a mighty heave-ho, Silver gallops away into the sunset leaving the Lone Ranger to warm himself by the flames. Jose has left it very clear. Nice job!
Click to play embedded YouTube video.
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Wed Dec 16, 2015 5:13 pm
by Visual_Astronomer
Under very dark skies, with a 20" scope, at about 140x through a narrow-band filter I can barely, just barely, make out a dark indentation in the faint background glow. Photos may reveal a horse, head or tail, but it's not much to look at with your eye. I can at least claim "I've seen it."
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Wed Dec 16, 2015 9:08 pm
by Non Thermal Universe
Does one know which instrument was used for this picture?
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Wed Dec 16, 2015 10:58 pm
by geckzilla
Non Thermal Universe wrote:Does one know which instrument was used for this picture?
Chris Peterson wrote:Once again, it isn't a horse's head...
hh-ass.jpg
Isn't there a brand of hot chilli sauce that has a similar logo?
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Thu Dec 17, 2015 6:10 pm
by starsurfer
I would love to see the reflection nebulae near the left imaged in a closeup by maybe Adam Block.
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Thu Dec 17, 2015 6:55 pm
by DavidLeodis
When I click on the 'José Jiménez Priego' link in the credit I get a message in the Facebook website that states "The link you followed may have expired, or the Page may only be visible to an audience that you aren't in.". If the link has expired it seems far too early. If I need to be a member of Facebook to view what would have been brought up then it is wrong that a link in an APOD needs such a requirement.
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Thu Dec 17, 2015 7:07 pm
by Chris Peterson
DavidLeodis wrote:When I click on the 'José Jiménez Priego' link in the credit I get a message in the Facebook website that states "The link you followed may have expired, or the Page may only be visible to an audience that you aren't in.". If the link has expired it seems far too early. If I need to be a member of Facebook to view what would have been brought up then it is wrong that a link in an APOD needs such a requirement. :(
It's a flaw fundamental to Facebook. If it's the only connection to the online world somebody has, that's what they're going to provide, and that's all that APOD can include. Not much choice, given that the editors don't have any author access requirements when considering images (occasionally, there is no contact information at all).
I'd suggest you get a fake Facebook account. It's easily done, and allows you a degree of access to FB pages without compromising your own privacy.
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Thu Dec 17, 2015 7:43 pm
by DavidLeodis
Thanks for your help and suggestion Chris.
Something that I've noticed for some time now is the large number of image and/or social network accounts that some people have (not just APOD contributors) that I wonder how they ever get time to really concentrate on what they are providing!
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Thu Dec 17, 2015 8:07 pm
by Ann
Chris Peterson wrote:
DavidLeodis wrote:When I click on the 'José Jiménez Priego' link in the credit I get a message in the Facebook website that states "The link you followed may have expired, or the Page may only be visible to an audience that you aren't in.". If the link has expired it seems far too early. If I need to be a member of Facebook to view what would have been brought up then it is wrong that a link in an APOD needs such a requirement.
It's a flaw fundamental to Facebook. If it's the only connection to the online world somebody has, that's what they're going to provide, and that's all that APOD can include. Not much choice, given that the editors don't have any author access requirements when considering images (occasionally, there is no contact information at all).
I'd suggest you get a fake Facebook account. It's easily done, and allows you a degree of access to FB pages without compromising your own privacy.
I think this might be Chris' eleven thousand, one hundred and eleventh post.
His 11111th post.
Ann
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Thu Dec 17, 2015 8:13 pm
by Beyond
I was going to mention that, but it seems to be a little odd to me, so i didn't.
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Thu Dec 17, 2015 8:34 pm
by Chris Peterson
Beyond wrote:I was going to mention that, but it seems to be a little odd to me, so i didn't.
Well, I'm an odd guy.
Damn... I broke it!
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Thu Dec 17, 2015 11:01 pm
by Beyond
Awwwww, now you'll have to wait until your 22222nd post. But the good news is that you'll be even odder.
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Fri Dec 18, 2015 4:12 am
by geckzilla
He'll be a lot less odd on the 22222nd post.
Re: APOD: The Horsehead Nebula (2015 Dec 16)
Posted: Fri Dec 18, 2015 4:56 am
by Beyond
Yes, because of the 2's. However, there are 5 of them. That's why he'll be 'even odder'.
FALSTAFF: Prithee, no more prattling; go. I'll hold. This is
the third time; I hope good luck lies in odd
numbers. Away I go. They say there is divinity in
odd numbers, either in nativity, chance, or death. Away!
The Horsehead Nebula
Jose has left it very clear. Nice job!
