APOD: Veil Nebula: Wisps of an Exploded Star (2017 Sep 19)

[APOD Robot]

Veil Nebula: Wisps of an Exploded Star

Explanation: Wisps like this are all that remain visible of a Milky Way star. About 7,000 years ago that star exploded in a supernova leaving the Veil Nebula. At the time, the expanding cloud was likely as bright as a crescent Moon, remaining visible for weeks to people living at the dawn of recorded history. Today, the resulting supernova remnant, also known as the Cygnus Loop, has faded and is now visible only through a small telescope directed toward the constellation of the Swan (Cygnus). The remaining Veil Nebula is physically huge, however, and even though it lies about 1,400 light-years distant, it covers over five times the size of the full Moon. The featured picture is a Hubble Space Telescope mosaic of six images together covering a span of only about two light years, a small part of the expansive supernova remnant. In images of the complete Veil Nebula, even studious readers might not be able to identify the featured filaments.

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[Chris Peterson]

Useful additional information.

Click to view full size image

[Boomer12k]

Outstanding close up...

:---[===] *

[sallyseaver]

I agree --- Outstanding closeup!
Wow!

[sallyseaver]

It looks like a plasma to me with multi-element ionized gas.

[sallyseaver]

Chris, thanks for the extra info. You provided the colors for the different elements in the plasma and a scale for the image.

[neufer]

.

• King Henry VI, part III : Act II, scene II

EDWARD: A wisp of straw were worth a thousand crowns,

• To make this shameless callet know herself.

[Mtnrockdhh]

The left tip of the Witch's Broom?

[Guest]

The north (left) tip of the Witch's Broom?

[bystander]

Useful additional information.

http://www.spacetelescope.org/news/heic1520/
http://hubblesite.org/news_release/news/2015-29
http://heritage.stsci.edu/2015/29/

[Rules For]

Does anybody know what's happened to Hubble Heritage? They used to put out a new image every month, but it's been awhile.

[Ann]

Click to view full size image

Widefield Cygnus with the Veil Nebula.
Source: http://www.flickriver.com/photos/urlaub ... teresting/

Click to view full size image

Vela supernova remnant. Photo: Robert Gendler.

As supernova remnants go, the Veil Nebula is fairly bright and easy to photograph. Note in the picture at left the Veil Nebula at 7 o'clock.

Personally I find the Vela supernova remnant more beautiful than the Veil Nebula. The Vela SNR is located in a rich region of star formation and young stars, whereas the background of the Veil is made up of mostly old stars.

Ann

[MarkBour]

... Wisps like this are all that remain visible of a Milky Way star.

When today's APOD says "visible", I think they are distinguishing this easy-to-see material from the hard-to-see central X-ray source, Cygnus X-1 ... which is widely believed to be a stellar mass black hole. https://en.wikipedia.org/wiki/Cygnus_X-1.

[Ann]

... Wisps like this are all that remain visible of a Milky Way star.

When today's APOD says "visible", I think they are distinguishing this easy-to-see material from the hard-to-see central X-ray source, Cygnus X-1 ... which is widely believed to be a stellar mass black hole. https://en.wikipedia.org/wiki/Cygnus_X-1.

Click to view full size image

Cygnus X-1 and the Tulip Nebula.
Photo: Neil Fleming.

Please note that Cygnus X-1 is not the central source, X-ray or otherwise, of the Veil Nebula. (Is there a lot of X-rays in the Veil Nebula?)

Ann

[ta152h0]

This star must have been in the tunnel of love, or riding in the Pirates of the Caribean, at Disneyland

[Thwapwhacket]

Is there an explanation for the slightly darker horizontal band just above the center of the image?

[Case]

The two brightest spots in X-ray are Veil and Vela.

---

Is there a lot of X-rays in the Veil Nebula?

ROSAT found quite a lot of emission!

[bjmb]

splendid picture, but somewhat sloppy caption> 'Wisps like this are all that remain visible of a Milky Way star. About 7,000 years ago that star exploded in a supernova leaving the Veil Nebula. At the time, the expanding cloud was likely as bright as a crescent Moon, remaining visible for weeks to people living at the dawn of recorded history.' scientifically exact would be: 'Wisps like this are all that remain visible of a Milky Way star. About 7,000 years ago that star's explosion in a supernova became visible on earth, leaving the Veil Nebula. At the time, the expanding cloud was likely as bright as a crescent Moon, remaining visible for weeks to people living at the dawn of recorded history.' the explosion itself was of course dusted and done 7,000 years ago

[Chris Peterson]

splendid picture, but somewhat sloppy caption> 'Wisps like this are all that remain visible of a Milky Way star. About 7,000 years ago that star exploded in a supernova leaving the Veil Nebula. At the time, the expanding cloud was likely as bright as a crescent Moon, remaining visible for weeks to people living at the dawn of recorded history.' scientifically exact would be: 'Wisps like this are all that remain visible of a Milky Way star. About 7,000 years ago that star's explosion in a supernova became visible on earth, leaving the Veil Nebula. At the time, the expanding cloud was likely as bright as a crescent Moon, remaining visible for weeks to people living at the dawn of recorded history.' the explosion itself was of course dusted and done 7,000 years ago

No, the way it's worded is fine. We don't care when the explosion "actually" happened. What is relevant is when the light reached Earth. This is almost always true, and almost always the way things are dated astronomically. It is normal to treat the date of occurrence as the date of observation.

[neufer]

We don't care when the explosion "actually" happened. What is relevant is when the light reached Earth. This is almost always true, and almost always the way things are dated astronomically. It is normal to treat the date of occurrence as the date of observation.

It's not that we don't care...
it's simply that we don't know precisely when the explosion "actually" happened.

Hence, we'll just call the accurately known spacetime interval Δs "the time":

In four-dimensional spacetime, the analog to distance is the spacetime interval Δs:

---

The spacetime interval Δs between any two events is independent
of the inertial frame of reference in which they are recorded.

[Chris Peterson]

We don't care when the explosion "actually" happened. What is relevant is when the light reached Earth. This is almost always true, and almost always the way things are dated astronomically. It is normal to treat the date of occurrence as the date of observation.

It's not that we don't care...
it's simply that we don't know precisely when the explosion "actually" happened.

Sometimes. But it's true that we most often don't care at all, because the information isn't of any use. We're usually observing the evolution of some event, and an offset from when we observe it is constant, and therefore irrelevant.

There are exceptions for things observed at cosmological distances. But not typically for things observed in our own or nearby galaxies.

[groelofs]

Looks like it's where my best guess was, but the misleading wording on the nebula's size ("covers over five times the size of the full Moon") made it uncertain. I believe the intended wording is that the diameter is about five times that of the full Moon, which would make the overall nebula about about 61 light years across. As actually worded, however, it sounds like the area is five times that of the Moon, which would imply a diameter of about 27 light years, I think.

[geckzilla]

Does anybody know what's happened to Hubble Heritage? They used to put out a new image every month, but it's been awhile.

I asked a few months back, and didn't get a reply. They're prepping for JWST over at STScI. ESA still publishes a new image every week or so over at spacetelescope.org.

[MarkBour]

... Wisps like this are all that remain visible of a Milky Way star.

When today's APOD says "visible", I think they are distinguishing this easy-to-see material from the hard-to-see central X-ray source, Cygnus X-1 ... which is widely believed to be a stellar mass black hole. https://en.wikipedia.org/wiki/Cygnus_X-1.

Click to view full size image

Cygnus X-1 and the Tulip Nebula.
Photo: Neil Fleming.

Please note that Cygnus X-1 is not the central source, X-ray or otherwise, of the Veil Nebula. (Is there a lot of X-rays in the Veil Nebula?)

Ann

If Cygnus X-1 is in the wrong location, then is there another black hole in about the right place? Cygnus X-5, perhaps?

[Ann]

MarkBour wrote:
If Cygnus X-1 is in the wrong location, then is there another black hole in about the right place? Cygnus X-5, perhaps?

Yes, it would seem that Cygnus X-5 is the X-ray source of the Cygnus Loop with the Veil Nebula.

Wikipedia wrote:

The X-ray source Cygnus X-5 coincides with SNR G074.0-08.6 (the Cygnus Loop), located at J2000 RA 20h 51.1m Dec +30° 41′, observed by Uhuru at 4U 2046+31. This source also has catalogue numbers 1E 2049.4+3050, 1H 2050+310, and 1M 2051+309, having been observed by the Einstein Observatory, HEAO 1, and OSO 7, respectively.
The Cygnus Loop is a strong source of soft X-rays.

But nothing seems to be known about Cygnus X-5. Wikipedia does not provide a link to more information about Cygnus X-5. So we can't say that Cygnus X-5 is a black hole.

Ann