APOD: Galactic Cirrus: Mandel Wilson 9 (2023 Jul 21)

[APOD Robot]

Galactic Cirrus: Mandel Wilson 9

Explanation: The combined light of stars along the Milky Way are reflected by these cosmic dust clouds that soar 300 light-years or so above the plane of our galaxy. Known to some as integrated flux nebulae and commonly found at high galactic latitudes, the dusty galactic cirrus clouds are faint. But they can be traced over large regions of the sky toward the North and South Galactic poles. Along with the reflection of starlight, studies indicate the dust clouds produce a faint reddish luminescence as interstellar dust grains convert invisible ultraviolet radiation to visible red light. Also capturing nearby Milky Way stars and distant background galaxies, this remarkably deep, wide-field image explores a complex of faint galactic cirrus known as Mandel Wilson 9. It spans over three degrees across planet Earth's skies toward the far southern constellation Apus.

<< Previous APOD

This Day in APOD

Next APOD >>

[sphere49]

Would it be OK to point out an editing error? "The combined light of stars along the Milky Way are reflected..." should read "is reflected." Agreement of subject ("light") and verb. I wouldn't trouble to comment about this, but two minutes before opening this APOD I was ranting about this very topic -- the demise of agreement of subject and verb -- in an unrelated email to a friend.

[zendae1]

Would it be OK to point out an editing error? "The combined light of stars along the Milky Way are reflected..." should read "is reflected." Agreement of subject ("light") and verb. I wouldn't trouble to comment about this, but two minutes before opening this APOD I was ranting about this very topic -- the demise of agreement of subject and verb -- in an unrelated email to a friend.

As English was one of my majors eons ago, I've long since given up any hope. I just finished editing 61 game cards in a very complex world conquest board game that friends developed and are ready to release. "Astonished" is an understatement re the unforgivable grammatical gaffes that American-educated people committed in the writing of these. Handwriting is another issue. Can kids even write anymore? In Catholic school in the 1960s we would suffer a blow to the writing hand if we dared to print...I suppose it's all part of "evolution" (says the cheeked tongue)...

afa today's photo, I never knew such luminescent things existed. I wonder if, before even yak lamps, our ancestors could all see their shadows on all the clear moonless nights. I wonder how intrigued they were by their shadows.

[Chris Peterson]

Would it be OK to point out an editing error? "The combined light of stars along the Milky Way are reflected..." should read "is reflected." Agreement of subject ("light") and verb. I wouldn't trouble to comment about this, but two minutes before opening this APOD I was ranting about this very topic -- the demise of agreement of subject and verb -- in an unrelated email to a friend.

As English was one of my majors eons ago, I've long since given up any hope. I just finished editing 61 game cards in a very complex world conquest board game that friends developed and are ready to release. "Astonished" is an understatement re the unforgivable grammatical gaffes that American-educated people committed in the writing of these. Handwriting is another issue. Can kids even write anymore? In Catholic school in the 1960s we would suffer a blow to the writing hand if we dared to print...I suppose it's all part of "evolution" (says the cheeked tongue)...

afa today's photo, I never knew such luminescent things existed. I wonder if, before even yak lamps, our ancestors could all see their shadows on all the clear moonless nights. I wonder how intrigued they were by their shadows.

And then there is the problem with misused words. This material certainly isn't "luminsescent".

[Ann]

Would it be OK to point out an editing error? "The combined light of stars along the Milky Way are reflected..." should read "is reflected." Agreement of subject ("light") and verb. I wouldn't trouble to comment about this, but two minutes before opening this APOD I was ranting about this very topic -- the demise of agreement of subject and verb -- in an unrelated email to a friend.

As English was one of my majors eons ago, I've long since given up any hope. I just finished editing 61 game cards in a very complex world conquest board game that friends developed and are ready to release. "Astonished" is an understatement re the unforgivable grammatical gaffes that American-educated people committed in the writing of these. Handwriting is another issue. Can kids even write anymore? In Catholic school in the 1960s we would suffer a blow to the writing hand if we dared to print...I suppose it's all part of "evolution" (says the cheeked tongue)...

afa today's photo, I never knew such luminescent things existed. I wonder if, before even yak lamps, our ancestors could all see their shadows on all the clear moonless nights. I wonder how intrigued they were by their shadows.

Yak with a 'congenital headlamp' hidden under all that fur and gear? No, it should probably be an 'innate' headlamp, a thing that the yak was born with!

---

Yak lamps providing light for our ancestors!!! So unbelievably funny!

(And before there were yak lamps - before the yaks had the mutation that made lamps grow out of their heads - our ancestors had luminescent galactic cirrus clouds lighting up their nights! Seriously, you're killing me!!!)

But I sympathize with those who make all those English grammar mistakes, particularly those who say "the light of stars are reflected" instead of "the light of stars is reflected". That's the kind of mistake that I make all the time. I try to catch them, and I usually do, but if you read my posts a lot here at Starship Asterisk* you must have seen me making them. You must have.

And there are so many other grammar mistakes I can make - just yesterday I struggled with whether to write "in that manner" or "by that manner". Goodness, the number of mistakes you can make! And now, two seconds ago, I decided to look up the phrase "struggle with whether" because I wasn't absolutely sure you can use it. (Apparently you can.)

Also I had to look up "yak". Yes, I was 95% certain that I knew what a yak is, but 95% isn't good enough, so I had to make sure. And yes, it really is that big wooly creature with big horns that I thought it was.

(My spellcheck protests at the word "wooly". Right, yeah, it should be "woolly".)

Okay, now that I'm talking about that yak that lit up the nights for our ancestors, would you actually say "a congenital headlamp"? Congenital? Would you call that lamp natural, ancestral, hereditary or congenital? Perhaps biological? No, it should be "innate", perhaps? A lamp as a natural born accessory?

In Swedish you would say "medfödd", which means that you were born with something. Imagine a newborn baby boy or girl born with a headlamp peeking out of its forehead. Must have made the delivery of the baby extra painful for Mom.

(Would it have been okay to write "peeking out from its forehead"? )

There are a million grammar questions I could ask you lucky native English speakers, but I never ask. I just plod on, looking up things all the time, and hope you won't catch me making too too many gaffes.

Ann

[orin stepanek]

MandelWilson9; A dust cloud worth looking at!

[johnnydeep]

Would it be OK to point out an editing error? "The combined light of stars along the Milky Way are reflected..." should read "is reflected." Agreement of subject ("light") and verb. I wouldn't trouble to comment about this, but two minutes before opening this APOD I was ranting about this very topic -- the demise of agreement of subject and verb -- in an unrelated email to a friend.

As English was one of my majors eons ago, I've long since given up any hope. I just finished editing 61 game cards in a very complex world conquest board game that friends developed and are ready to release. "Astonished" is an understatement re the unforgivable grammatical gaffes that American-educated people committed in the writing of these. Handwriting is another issue. Can kids even write anymore? In Catholic school in the 1960s we would suffer a blow to the writing hand if we dared to print...I suppose it's all part of "evolution" (says the cheeked tongue)...

afa today's photo, I never knew such luminescent things existed. I wonder if, before even yak lamps, our ancestors could all see their shadows on all the clear moonless nights. I wonder how intrigued they were by their shadows.

And then there is the problem with misused words. This material certainly isn't "luminsescent".

And then there are those who constantly misspell words.

But I might not understand your point, though the OP's use of "luminescent" did strike me as odd.

This is the passage from the APOD text:

Along with the reflection of starlight, studies indicate the dust clouds produce a faint reddish luminescence as interstellar dust grains convert invisible ultraviolet radiation to visible red light.

I presume simple reflection is in no way caused by luminescence, but what about when the dust grains "convert UV to visible light". That's presumably happening when electrons absorb UV photons but then emit lower energy visible photons, right?

Wikipedia says:

Luminescence is the "spontaneous emission of radiation from an electronically excited species (or from a vibrationally excited species) not in thermal equilibrium with its environment", according to the IUPAC definition. A luminescent object is emitting "cold light", in contrast to "incandescence", where an object only emits light after heating.[1] Generally, the emission of light is due to the movement of electrons between different energy levels within an atom after excitation by external factors. However, the exact mechanism of light emission in "vibrationally excited species" is unknown, as seen in sonoluminescence.

Doesn't the explanation in blue fit what's happening when dust grains absorb UV and reemit visible light?

[johnnydeep]

So, are there more than two background galaxies in this image? Here are at least two clear ones:

[johnnydeep]

Alright Ann, where'd you get that caption on your yak pic? I have no idea what a "congenital headlamp" would be!

[Chris Peterson]

As English was one of my majors eons ago, I've long since given up any hope. I just finished editing 61 game cards in a very complex world conquest board game that friends developed and are ready to release. "Astonished" is an understatement re the unforgivable grammatical gaffes that American-educated people committed in the writing of these. Handwriting is another issue. Can kids even write anymore? In Catholic school in the 1960s we would suffer a blow to the writing hand if we dared to print...I suppose it's all part of "evolution" (says the cheeked tongue)...

afa today's photo, I never knew such luminescent things existed. I wonder if, before even yak lamps, our ancestors could all see their shadows on all the clear moonless nights. I wonder how intrigued they were by their shadows.

And then there is the problem with misused words. This material certainly isn't "luminsescent".

And then there are those who constantly misspell words. :ssmile:

But I might not understand your point, though the OP's use of "luminescent" did strike me as odd.

This is the passage from the APOD text:

Along with the reflection of starlight, studies indicate the dust clouds produce a faint reddish luminescence as interstellar dust grains convert invisible ultraviolet radiation to visible red light.

I presume simple reflection is in no way caused by luminescence, but what about when the dust grains "convert UV to visible light". That's presumably happening when electrons absorb UV photons but then emit lower energy visible photons, right?

Wikipedia says:

Luminescence is the "spontaneous emission of radiation from an electronically excited species (or from a vibrationally excited species) not in thermal equilibrium with its environment", according to the IUPAC definition. A luminescent object is emitting "cold light", in contrast to "incandescence", where an object only emits light after heating.[1] Generally, the emission of light is due to the movement of electrons between different energy levels within an atom after excitation by external factors. However, the exact mechanism of light emission in "vibrationally excited species" is unknown, as seen in sonoluminescence.

Doesn't the explanation in blue fit what's happening when dust grains absorb UV and reemit visible light?

But that is completely below the noise level in this image. So all we're seeing is reflection. The dust as seen here is luminous, but not luminescent.

[Ann]

Alright Ann, where'd you get that caption on your yak pic? I have no idea what a "congenital headlamp" would be!

Exactly, Johnny. It was totally wrong. The word I was looking for was probably "innate". But when I asked Google for English translations of the Swedish word "medfödd", literally "born with", Google didn't provide me with "innate". I just remembered that word now, many hours after I needed it.

I'll go edit my first post now. Groan. As if I don't have to do that over and over in so many posts that I write.

Ann

[johnnydeep]

Alright Ann, where'd you get that caption on your yak pic? I have no idea what a "congenital headlamp" would be!

Exactly, Johnny. It was totally wrong. The word I was looking for was probably "innate". But when I asked Google for English translations of the Swedish word "medfödd", literally "born with", Google didn't provide me with "innate". I just remembered that word now, many hours after I needed it.

I'll go edit my first post now. Groan. As if I don't have to do that over and over in so many posts that I write.

Ann

I still don't get it at all. An "innate" headlamp on a Yak doesn't make any more sense. And "innate" means essentially the same think as "congenital":

congenital (kən-jĕn′ĭ-tl) - adjective
1. Of or relating to a condition that is present at birth, as a result of either heredity or environmental influences.
2. Being or having an essential characteristic as if by nature; inherent or inveterate.
3. Existing at, or dating from, birth; pertaining to one from birth; born with one; connate; constitutional; natural. See connate and native.

So, what "headlamp" does a yak have, whether having been born with it, or worn as ornamentation provided by a human?

Also, from what I can find, a "yak lamp" is just a lamp that burns yak butter:

Butter lamps or butterlamps (Tibetan: དཀར་མེ་, Wylie: dkar me; simplified Chinese: 酥油灯; traditional Chinese: 酥油燈; pinyin: sūyóu dēng) are a common feature of Tibetan Buddhist temples and monasteries throughout the Himalayas. The lamps traditionally burn clarified yak butter, but now often use vegetable oil or vanaspati ghee.

[johnnydeep]

And then there is the problem with misused words. This material certainly isn't "luminsescent".

And then there are those who constantly misspell words.

But I might not understand your point, though the OP's use of "luminescent" did strike me as odd.

This is the passage from the APOD text:

Along with the reflection of starlight, studies indicate the dust clouds produce a faint reddish luminescence as interstellar dust grains convert invisible ultraviolet radiation to visible red light.

I presume simple reflection is in no way caused by luminescence, but what about when the dust grains "convert UV to visible light". That's presumably happening when electrons absorb UV photons but then emit lower energy visible photons, right?

Wikipedia says:

Luminescence is the "spontaneous emission of radiation from an electronically excited species (or from a vibrationally excited species) not in thermal equilibrium with its environment", according to the IUPAC definition. A luminescent object is emitting "cold light", in contrast to "incandescence", where an object only emits light after heating.[1] Generally, the emission of light is due to the movement of electrons between different energy levels within an atom after excitation by external factors. However, the exact mechanism of light emission in "vibrationally excited species" is unknown, as seen in sonoluminescence.

Doesn't the explanation in blue fit what's happening when dust grains absorb UV and reemit visible light?

But that is completely below the noise level in this image. So all we're seeing is reflection. The dust as seen here is luminous, but not luminescent.

Alright, but the red light we're NOT seeing here, but still described as occurring in the APOD, can still correctly be said to be caused by "luminescence", correct?

[Ann]

Alright Ann, where'd you get that caption on your yak pic? I have no idea what a "congenital headlamp" would be!

Exactly, Johnny. It was totally wrong. The word I was looking for was probably "innate". But when I asked Google for English translations of the Swedish word "medfödd", literally "born with", Google didn't provide me with "innate". I just remembered that word now, many hours after I needed it.

I'll go edit my first post now. Groan. As if I don't have to do that over and over in so many posts that I write.

Ann

I still don't get it at all. An "innate" headlamp on a Yak doesn't make any more sense. And "innate" means essentially the same think as "congenital":

congenital (kən-jĕn′ĭ-tl) - adjective
1. Of or relating to a condition that is present at birth, as a result of either heredity or environmental influences.
2. Being or having an essential characteristic as if by nature; inherent or inveterate.
3. Existing at, or dating from, birth; pertaining to one from birth; born with one; connate; constitutional; natural. See connate and native.

So, what "headlamp" does a yak have, whether having been born with it, or worn as ornamentation provided by a human?

Also, from what I can find, a "yak lamp" is just a lamp that burns yak butter:

Butter lamps or butterlamps (Tibetan: དཀར་མེ་, Wylie: dkar me; simplified Chinese: 酥油灯; traditional Chinese: 酥油燈; pinyin: sūyóu dēng) are a common feature of Tibetan Buddhist temples and monasteries throughout the Himalayas. The lamps traditionally burn clarified yak butter, but now often use vegetable oil or vanaspati ghee.

So I didn't understand the expression "yak lamp", then. I thought, for real, that it was a lamp protruding out of yaks. No, of course I realized that there can never have been any such lamps, but the very suggestion that there might have been some was so incredibly unbelievably funny to me. I kept seeing the yak with its lamp coming out from between its eyes, providing light for our Pleistocene ancestors!

Sorry, Johnny! It was just such an incredible joke to me and I couldn't help going with it.

But there you have it, my English isn't good enough. I had never heard of any real yak lamps, so I misunderstood the whole thing.

Ann

[Chris Peterson]

And then there are those who constantly misspell words. :ssmile:

But I might not understand your point, though the OP's use of "luminescent" did strike me as odd.

This is the passage from the APOD text:



I presume simple reflection is in no way caused by luminescence, but what about when the dust grains "convert UV to visible light". That's presumably happening when electrons absorb UV photons but then emit lower energy visible photons, right?

Wikipedia says:



Doesn't the explanation in blue fit what's happening when dust grains absorb UV and reemit visible light?

But that is completely below the noise level in this image. So all we're seeing is reflection. The dust as seen here is luminous, but not luminescent.

Alright, but the red light we're NOT seeing here, but still described as occurring in the APOD, can still correctly be said to be caused by "luminescence", correct?

Yes.

[johnnydeep]

...

So I didn't understand the expression "yak lamp", then. I thought, for real, that it was a lamp protruding out of yaks. No, of course I realized that there can never have been any such lamps, but the very suggestion that there might have been some was so incredibly unbelievably funny to me. I kept seeing the yak with its lamp coming out from between its eyes, providing light for our Pleistocene ancestors!

Sorry, Johnny! It was just such an incredible joke to me and I couldn't help going with it.

But there you have it, my English isn't good enough. I had never heard of any real yak lamps, so I misunderstood the whole thing.

Ann

No worries. I've been known to completely miss the joke on occasion so I feared I might have been doing that again here.

[johnnydeep]

But that is completely below the noise level in this image. So all we're seeing is reflection. The dust as seen here is luminous, but not luminescent.

Alright, but the red light we're NOT seeing here, but still described as occurring in the APOD, can still correctly be said to be caused by "luminescence", correct?

Yes.

✓

[starsurfer]

So, are there more than two background galaxies in this image? Here are at least two clear ones:


galactic cirrus and background galaxies.jpg

I don't know why the desciption doesn't mention these are IC 4633 and IC 4635.

[Ann]

So, are there more than two background galaxies in this image? Here are at least two clear ones:


galactic cirrus and background galaxies.jpg

I don't know why the desciption doesn't mention these are IC 4633 and IC 4635.

Very good point, Starsurfer! The photographer himself mentioned the galaxies here.


Josep M. Drudis has taken a great picture of IC 4633 and IC 3635:

IC 4633 (left) and IC 4635 with small companion 2MASSX J17151422-7727251.
Credit: Josep M. Drudis.

Ann

[johnnydeep]

So, are there more than two background galaxies in this image? Here are at least two clear ones:


galactic cirrus and background galaxies.jpg

I don't know why the desciption doesn't mention these are IC 4633 and IC 4635.

Very good point, Starsurfer! The photographer himself mentioned the galaxies here.


Josep M. Drudis has taken a great picture of IC 4633 and IC 3635:

IC 4633 and IC 4635 Josep M Drudis.png

IC 4633 (left) and IC 4635 with small companion 2MASSX J17151422-7727251.
Credit: Josep M. Drudis.

Ann

Also tagged in the interactive astrobin image:

galactic cirrus and background galaxies astrobin.jpg (30 KiB) Viewed 3535 times

[NGC3314]

So, are there more than two background galaxies in this image? Here are at least two clear ones:


galactic cirrus and background galaxies.jpg

Ahh, IC 4633 and IC 4635. Those are among the few nearby galaxies partly seen through thicker lanes of Milky Way dust, allowing study parallel to the way one can look at galaxies backlit by more distant ones. (If only the scattered foreground light from the dust weren't almost the same surface brightness as that part of IC 4633 in visible light...)