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HH 222: The Waterfall Nebula

Explanation: What created the Waterfall Nebula? No one knows. The structure seen in the region of NGC 1999 in the Great Orion Molecular Cloud complex is one of the more mysterious structures yet found on the sky. Designated HH-222, the elongated gaseous stream stretches about ten light years and emits an unusual array of colors. One hypothesis is that the gas filament results from the wind from a young star impacting a nearby molecular cloud. That would not explain, however, why the Waterfall and fainter streams all appear to converge on a bright but unusual non thermal radio source located toward the upper left of the curving structure. Another hypothesis is that the unusual radio source originates from a binary system containing a hot white dwarf, neutron star, or black hole, and that the Waterfall is just a jet from this energetic system. Such systems, though, are typically strong X-rays emitters, and no X-rays have been detected. For now, this case remains unsolved. Perhaps well-chosen future observations and clever deductive reasoning will unlock the true origin of this enigmatic wisp in the future.

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I like the magnified -Water fall- link picture better. The red tube with the five white ovals on it,at the bottom of the waterfall, seems rather unusual itself. At least to me. After staring at the red tube for a while, with a magnifying glass, it resembles a baseball bat with a star on the end of it's handle. The barrel has five ovals in a row on it, with the bottom two being turned perpendicular to the bat. Anyone up for a game of Spaceball

Look at APOD Nov. 29, '99 to see how much APOD has improved. Great job, editors! My hat's off to you for your devotion to my pleasure and enlightenment.

Beyond wrote:I like the magnified -Water fall- link picture better. The red tube with the five white ovals on it,at the bottom of the waterfall, seems rather unusual itself. At least to me. After staring at the red tube for a while, with a magnifying glass, it resembles a baseball bat with a star on the end of it's handle. The barrel has five ovals in a row on it, with the bottom two being turned perpendicular to the bat. Anyone up for a game of Spaceball

I believe you are referring to HH-34.

The apparent flow may be the underlying structure or mountain that is expanding. The waterfall itself being disconnected is merely stretching. While the image is striking, the mountain itself is clearly actively involved in stellar evolution and is convoluted in a manner that gives the waterfall its shape.

Fascinating.


Ann

bystander wrote:I believe you are referring to HH-34.

Yup....If by HH-34 you mean the red tubie looking thingy. It shows up a LOT better when you go to the Waterfall link and click on the picture to magnify it.

What created the Waterfall Nebula? No one knows.

You might consider saying instead, "We don't know." Else you are speaking for all persons, which is patently absurd, and smacks of pontification.

Nothing absurd about saying "no one knows" when no one knows.

ah, the old country . . it takes me back to Enniskerry!

waterfall with neither lake nor rivers, it must be a stagnant waterfall

Vincent Pinto wrote:

What created the Waterfall Nebula? No one knows.

You might consider saying instead, "We don't know." Else you are speaking for all persons, which is patently absurd, and smacks of pontification.

If the APOD folks say "no one knows" something about astronomy there's a good chance of it being the true situation and that's instructive. And of course we can reserve our judgement if we've found them to speak falsely in such situations in the past. But If they only say "we don't know" when they don't, it's clearly true but doesn't tell us the general state of knowledge about the issue.

As an example suggested by your post, if the Pope did say "no one knows" about an issue I personally would be unlikely to believe that.

Oh, and yet another great APOD. Beautiful and mysterious, too!

You guys need to shed a little more light on the situation:

http://upload.wikimedia.org/wikipedia/c ... _HH-34.jpg

In this image the entire structure (with the corresponding curved streamer on the far side from the black hole) is clearly visible.

JD

Here's a 14-year time lapse video. These jets zip right along:

http://hubblesite.org/newscenter/archiv ... 0/video/f/

As I understand it there are competing hypotheses about the "waterfall" itself, one holding that it's a shock wave, which presumably would over time manifest itself more toward the top and right of where we see it now, and the other hypothesis holding that it's a jet, likely moving out from the upper left end. For what extremely little it's worth, my intuition is claiming it could concieve of the former case, with the non-intuitive shape perhaps due to different materials the wave passed through in the upper part versus the lower part causing slower or faster progress. But my intuition is having a real tough time explaining a jet with a bent shape like that one.

I don't know what causes it either; but waterfall is a good name for it.
Hey! Ya notice the curious kitty?

What a wonderful picture of this phenomenon in the sky. While looking at it closely I picture the head and partial body of a giant ape at the left of the waterfall looking at me. He has one perfect eye and one with a star. Amazing!!!
I look forward every day to see the APOD. Thank you.

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HH-222 in the region of NGC 1999

Quick, call 555-

Beyond wrote: Yup....If by HH-34 you mean the red tubie looking thingy. It shows up a LOT better when you go to the Waterfall link and click on the picture to magnify it.

HH-34 is the proto-star (the star on the end of your bat), the jet (your bat), and the shock wave at the end of the jet. There is also a unseen jet in the opposite direction, as evident from the shock wave at the top of the cropped image.

Would love it, APOD, if you put a Facebook "share" button with your photos. Would love it!

Hunter wrote:Would love it, APOD, if you put a Facebook "share" button with your photos. Would love it!

Facebook: Astronomy Picture of the Day (APOD)

Share the page links or the images from the photo albums!
Like the page! Tell your friends!

That pic is just filled to the brim with WTF?

Wonderful, thanks APOD!

What a gorgeous formation - hope the knowledge of how it formed and will change in the future is discovered .....

bystander wrote:

Beyond wrote: Yup....If by HH-34 you mean the red tubie looking thingy. It shows up a LOT better when you go to the Waterfall link and click on the picture to magnify it.

HH-34 is the proto-star (the star on the end of your bat), the jet (your bat), and the shock wave at the end of the jet. There is also a unseen jet in the opposite direction, as evident from the shock wave at the top of the cropped image.

So... HH-34 is the white spot at the handle. Then going down to the barrel of the bat, what are those 5-oval white shapes in a row??
They show up pretty good using the magnified waterfall link picture and a magnifying glass. That's why i call it a bat. In the magnified picture, the length under HH-34 is thinner than farther down where the 5-oval white spots are, the barrel of the bat.

No, HH-34 is the proto-star, jets, and shock waves. Practically all of the subimage I presented above.

The jets would expand as they get further from the source, the white spots, I suspect are just a bit more energetic.

Here is a close up.