Starship Asterisk*

The Butterfly Nebula from Hubble

Explanation: The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects. Though its wingspan covers over 3 light-years, NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees C, the dying central star of this particular planetary nebula has become exceptionally hot, shining brightly in ultraviolet light but hidden from direct view by a dense torus of dust. This sharp close-up of the dying star's nebula was recorded in 2009 by the Hubble Space Telescope's Wide Field Camera 3, and is presented here in reprocessed colors. Cutting across a bright cavity of ionized gas, the dust torus surrounding the central star is near the center of this view, almost edge-on to the line-of-sight. Molecular hydrogen has been detected in the hot star's dusty cosmic shroud. NGC 6302 lies about 4,000 light-years away in the arachnologically correct constellation of the Scorpion (Scorpius).

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Great shot, but to me it looks sort of angry.

Some stars as they age are like people; some of them get bipolar.

I have a question. Would it be possible for APOD to frame the daily picture with a black background (rather than white) when it is clicked? I think it would add to the viewing experience.

I've been a big fan of APOD since I first came across it in the late 1990s. Thanks for the work you do.

Ann wrote:What I find most interesting about today's APOD is the general similarity in shape between this planetary nebula and the nebula created by monster star Eta Carina.

Ann

Isn't that like comparing a regular onion to a red onion?

Also isn't this usually called the Bug Nebula? I have to admit I prefer the original version, this one seems less magical.

BDanielMayfield wrote:Great shot, but to me it looks sort of angry.

Isn't red also the colour of passion?

There are many strange blue spots in the picture. Many of these blue spots are in close proximity just below star images. What are these blue spots?

OOOOOO.....Pretty!!!!!!!!!!!!!!!! MOTHRA.....

And it even has a Star for an Eye!!!!!

I take it, we are see this from the side....and not the "front"...which may look more like an "EYE"????

:---[===] *

bentsn wrote:There are many strange blue spots in the picture. Many of these blue spots are in close proximity just below star images. What are these blue spots?

These are CAMERA ARTIFACTS....my camera makes HEAT speckles...and these look like those...

Plus, it is a reprocessed photo....so, they may have been "brought out" in processing. Especially in areas of CONTRAST....I think...

:---[===] *

BDanielMayfield wrote:Great shot, but to me it looks sort of angry.

Some stars as they age are like people;

"Get off of my gravitational field!"

So blue is the new white.

When a picture is taken by Hubble of the Butterfly Nebula for example, are we seeing the beginning of the explosion, in the middle, or at the end?

icman wrote:When a picture is taken by Hubble of the Butterfly Nebula for example, are we seeing the beginning of the explosion, in the middle, or at the end?

It depends on how you define "explosion". In this case, the energetic event is done, and all we're seeing is material moving by momentum alone. I'd say that means the explosion is essentially over. But others might define it differently.

Boomer12k wrote:

bentsn wrote:There are many strange blue spots in the picture. Many of these blue spots are in close proximity just below star images. What are these blue spots?

These are CAMERA ARTIFACTS....my camera makes HEAT speckles...and these look like those...

Plus, it is a reprocessed photo....so, they may have been "brought out" in processing. Especially in areas of CONTRAST....I think...

:---[===] *

They are not artifacts. Having worked with the datasets before, I know these particular Hubble data are very nice and clean and have very few artifacts. What has happened here is either the intentional or accidental misalignment of the blue channel. Red is ok. I think green is slightly misaligned but it's not obvious. And then blue is off by several pixels. Here is an animation which shows all three channels in grayscale which may help you understand.

Why is this nebula shaped like this? Was it punctured by something? Why are some explosions flat, some round, some shaped like dumb bells, and some are just a mess with no apparent shape? I expect the shape of the nebula has a lot to say about what it looked like before it exploded.

bko wrote:Why is this nebula shaped like this? Was it punctured by something? Why are some explosions flat, some round, some shaped like dumb bells, and some are just a mess with no apparent shape? I expect the shape of the nebula has a lot to say about what it looked like before it exploded.

This one looks like an intermediate aged planetary nebula to me. Part of the problem is that we see them from all different angles and it makes it very hard to make comparisons. on top of that, every star seems to explode with its own unique style. Complex shapes have been attributed to orbiting companions. In general, though, the more organized ones which look like smooth bells or hourglasses are younger while the disorganized looking ones are older.

geckzilla wrote:What has happened here is either the intentional or accidental misalignment of the blue channel. Red is ok. I think green is slightly misaligned but it's not obvious. And then blue is off by several pixels.

That nicely explains those swaths of blue where there should be something closer to white.

Some of the links at the end of the commentary indicate that the displayed form is the circumstellar disk of the star. So the nebulosity is mostly molecular hydrogen in that disk. Normally that would mean planets, other companion stars...? Right?

bactame wrote:Some of the links at the end of the commentary indicate that the displayed form is the circumstellar disk of the star. So the nebulosity is mostly molecular hydrogen in that disk. Normally that would mean planets, other companion stars...? Right?

As hydrogen is the most abundant element it's presence wouldn't imply the existence of other bodies in this system. But on the other hand the very existence of the star that ejected the nebula makes it quite likely that there were/are some planets in this system. I say this because planet formation seems to be a natural by-product of the star formation process.

This notion leads to the question, can stars form without a planetary system also forming in the mix?

geckzilla wrote:

Boomer12k wrote:

bentsn wrote:There are many strange blue spots in the picture. Many of these blue spots are in close proximity just below star images. What are these blue spots?

These are CAMERA ARTIFACTS....my camera makes HEAT speckles...and these look like those...

Plus, it is a reprocessed photo....so, they may have been "brought out" in processing. Especially in areas of CONTRAST....I think...

:---[===] *

They are not artifacts. Having worked with the datasets before, I know these particular Hubble data are very nice and clean and have very few artifacts. What has happened here is either the intentional or accidental misalignment of the blue channel. Red is ok. I think green is slightly misaligned but it's not obvious. And then blue is off by several pixels. Here is an animation which shows all three channels in grayscale which may help you understand.

channel_ani.gif

I wondered about that too. Any chance we could get the full size image realigned properly? It's gorgeous!