APOD: The Multiwavelength Crab (2022 Mar 04)

APOD Robot · Post by **APOD Robot** » Fri Mar 04, 2022 5:05 am

The Multiwavelength Crab

Explanation: The Crab Nebula is cataloged as M1, the first object on Charles Messier's famous list of things which are not comets. In fact, the Crab is now known to be a supernova remnant, expanding debris from massive star's death explosion, witnessed on planet Earth in 1054 AD. This brave new image offers a 21st century view of the Crab Nebula by presenting image data from across the electromagnetic spectrum as wavelengths of visible light. From space, Chandra (X-ray) XMM-Newton (ultraviolet), Hubble (visible), and Spitzer (infrared), data are in purple, blue, green, and yellow hues. From the ground, Very Large Array radio wavelength data is shown in red. One of the most exotic objects known to modern astronomers, the Crab Pulsar, a neutron star spinning 30 times a second, is the bright spot near picture center. Like a cosmic dynamo, this collapsed remnant of the stellar core powers the Crab's emission across the electromagnetic spectrum. Spanning about 12 light-years, the Crab Nebula is 6,500 light-years away in the constellation Taurus.

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bystander · Post by **bystander** » Fri Mar 04, 2022 5:08 am

discuss_apod.php?date=170511
viewtopic.php?t=37167

RocketRon · Post by **RocketRon** » Fri Mar 04, 2022 5:24 am

Big and beautiful, in a cosmic sort of way.

How big would it have appeared when first sighted here on planet Earth circa 1054 AD.
Presumably it has grown since then ?

How mysterious it must have seemed back then.
And that mysterious aspect still lingers.... ?

De58te · Post by **De58te** » Fri Mar 04, 2022 8:43 am

RocketRon wrote: ↑Fri Mar 04, 2022 5:24 am Big and beautiful, in a cosmic sort of way.

How big would it have appeared when first sighted here on planet Earth circa 1054 AD.
Presumably it has grown since then ?

How mysterious it must have seemed back then.
And that mysterious aspect still lingers.... ?

According to this simulation for 1054, it looked about twice the size and brightness of the full Moon.
https://en.wikipedia.org/wiki/SN_1054#/ ... aifeng.png

Ann · Post by **Ann** » Fri Mar 04, 2022 9:46 am

De58te wrote: ↑Fri Mar 04, 2022 8:43 am
RocketRon wrote: ↑Fri Mar 04, 2022 5:24 am Big and beautiful, in a cosmic sort of way.

How big would it have appeared when first sighted here on planet Earth circa 1054 AD.
Presumably it has grown since then ?

How mysterious it must have seemed back then.
And that mysterious aspect still lingers.... ?
According to this simulation for 1054, it looked about twice the size and brightness of the full Moon.
https://en.wikipedia.org/wiki/SN_1054#/ ... aifeng.png

I don't think you can talk about size here. At the distance of the star that exploded to create the Crab Nebula (around 6,500 light-years), the supernova would still have been a point source. But it was bright.

Wikipedia wrote:

Recent analysis of historical records have found that the supernova that created the Crab Nebula probably appeared in April or early May, rising to its maximum brightness of between apparent magnitude −7 and −4.5 (brighter even than Venus' −4.2 and everything in the night sky except the Moon) by July. The supernova was visible to the naked eye for about two years after its first observation.

Ann

orin stepanek · Post by **orin stepanek** » Fri Mar 04, 2022 12:28 pm

Multi wave length makes it look beautiful!

That dynamo in the
center though; sure looks awesome and scary!

Sa Ji Tario · Post by **Sa Ji Tario** » Fri Mar 04, 2022 1:17 pm

In the age of astronomy, the fashion was to look for comets and Charles. Messier was an enthusiastic comet seeker, on one occasion he noticed something that seemed to be one he followed for several nights but it did not move like a comet but like a celestial object, noticing the error he exclaimed: Cloudy skies! (we know he said "% $ / ()!" ª = · "!!!!!") and reported his finding so that others wouldn't get the same surprise and called it Messier 1, or M1. Then we discovered others, more than a hundred

Chris Peterson · Post by **Chris Peterson** » Fri Mar 04, 2022 3:16 pm

De58te wrote: ↑Fri Mar 04, 2022 8:43 am
RocketRon wrote: ↑Fri Mar 04, 2022 5:24 am Big and beautiful, in a cosmic sort of way.

How big would it have appeared when first sighted here on planet Earth circa 1054 AD.
Presumably it has grown since then ?

How mysterious it must have seemed back then.
And that mysterious aspect still lingers.... ?
According to this simulation for 1054, it looked about twice the size and brightness of the full Moon.
https://en.wikipedia.org/wiki/SN_1054#/ ... aifeng.png

Our displays can only represent a very narrow range of brightnesses compared to what our eyes can see. So star charts represent brightness by size. Visually, SN 1054 was just a bright star.

AVAO · Post by **AVAO** » Fri Mar 04, 2022 8:24 pm

Source: Jac Berne (flickr) The colors are a free interpretation of the scientific multiwavelenght data.

It is interesting that the crab also has a tail (visible in green at the top).
Obviously, cosmic explosions don't always spread at the same speed in all directions

To me it looks more like a pounding cosmic heart than an explosion.
https://apod.nasa.gov/apod/ap200119.html
I like this amazing time lapse shot over 9 years in the life of a crab.

johnnydeep · Post by **johnnydeep** » Fri Mar 04, 2022 10:13 pm

AVAO wrote: ↑Fri Mar 04, 2022 8:24 pm
Source: Jac Berne (flickr) The colors are a free interpretation of the scientific multiwavelenght data.

It is interesting that the crab also has a tail (visible in green at the top).
Obviously, cosmic explosions don't always spread at the same speed in all directions
To me it looks more like a pounding cosmic heart than an explosion.
https://apod.nasa.gov/apod/ap200119.html
I like this amazing time lapse shot over 9 years in the life of a crab.

I don't see any particular green tail-like portion, even in the individual (though too small) green optical image at https://hubblesite.org/contents/media/i ... Image.html. The only tail I see is the one on Messier's drawing!

AVAO · Post by **AVAO** » Sat Mar 05, 2022 10:13 am

johnnydeep wrote: ↑Fri Mar 04, 2022 10:13 pm
AVAO wrote: ↑Fri Mar 04, 2022 8:24 pm
Source: Jac Berne (flickr) The colors are a free interpretation of the scientific multiwavelenght data.

It is interesting that the crab also has a tail (visible in green at the top).
Obviously, cosmic explosions don't always spread at the same speed in all directions
To me it looks more like a pounding cosmic heart than an explosion.
https://apod.nasa.gov/apod/ap200119.html
I like this amazing time lapse shot over 9 years in the life of a crab.
I don't see any particular green tail-like portion, even in the individual (though too small) green optical image at https://hubblesite.org/contents/media/i ... Image.html. The only tail I see is the one on Messier's drawing!

Ok, I was looking for something better on the internet. Here is a link to a picture, where you can see the "tail" even better.
https://i.redd.it/hpck47vfh0i31.jpg

Ann · Post by **Ann** » Sat Mar 05, 2022 10:34 am

AVAO wrote: ↑Sat Mar 05, 2022 10:13 am
johnnydeep wrote: ↑Fri Mar 04, 2022 10:13 pm
AVAO wrote: ↑Fri Mar 04, 2022 8:24 pm
Source: Jac Berne (flickr) The colors are a free interpretation of the scientific multiwavelenght data.

It is interesting that the crab also has a tail (visible in green at the top).
Obviously, cosmic explosions don't always spread at the same speed in all directions
To me it looks more like a pounding cosmic heart than an explosion.
https://apod.nasa.gov/apod/ap200119.html
I like this amazing time lapse shot over 9 years in the life of a crab.
I don't see any particular green tail-like portion, even in the individual (though too small) green optical image at https://hubblesite.org/contents/media/i ... Image.html. The only tail I see is the one on Messier's drawing!
Ok, I was looking for something better on the internet. Here is a link to a picture, where you can see the "tail" even better.
https://i.redd.it/hpck47vfh0i31.jpg

Crab Nebula with tail (bottom).

: Supernova remnant Cassiopeia A with tail (at upper left). Image: Chandra.

To me it looks as if there is a tightly woven net of filaments, mostly glowing in hydrogen alpha, that keeps the hot inner gases of the supernova remnant contained. But if that net of filaments breaks, then the gas inside can flow out. Looks like that is what has happened to both the Crab Nebula and Cassiopeia A.

Ann

AVAO · Post by **AVAO** » Sat Mar 05, 2022 11:21 am

Ann wrote: ↑Sat Mar 05, 2022 10:34 am
AVAO wrote: ↑Sat Mar 05, 2022 10:13 am
johnnydeep wrote: ↑Fri Mar 04, 2022 10:13 pm

I don't see any particular green tail-like portion, even in the individual (though too small) green optical image at https://hubblesite.org/contents/media/i ... Image.html. The only tail I see is the one on Messier's drawing!
Ok, I was looking for something better on the internet. Here is a link to a picture, where you can see the "tail" even better.
https://i.redd.it/hpck47vfh0i31.jpg

hpck47vfh0i31[1].jpg
Crab Nebula with tail (bottom).
Supernova remnant Cassiopeia A with tail (at upper left). Image: Chandra.

To me it looks as if there is a tightly woven net of filaments, mostly glowing in hydrogen alpha, that keeps the hot inner gases of the supernova remnant contained. But if that net of filaments break, then the gas inside can flow out. Looks like that is what has happened to both the Crab Nebula and Cassiopeia A.

Ann

ThanX Ann

Your reasoning seems plausible to me. Alternatively, there is also the alternative idea of "filamentary jets", whatever that might be...

Fig. 3. Supernova remnants accelerate galactic cosmic rays. Left: A composite image of the roughly 300 year old supernova remnant Cas A, which is 3.4 kpc away. It has two oppositely opposed jets, the prominent one seen pointing toward the upper left. Image credit: NASA/CXC/SAO. Right: The 960 year old Crab Nebula supernova remnant which is located at a distance of 2 kpc. This Subaru telescope image shows remarkable details of its jet in this O III image that has been scaled logarithmically to show jet details. Inset: More detailed view of the jet.
From Rudie, G.C., Fesen, R.A., Yamada, T., 2008. The Crab Nebula's dynamical age as measured from its northern filamentary jet. Mon. Not. R. Astron. Soc. 384, 1200–1206. https://doi.org/10.1111/j.1365-2966.2007.12799.x, used by permission.
https://www.sciencedirect.com/topics/ea ... rab-nebula

Source: Chandra (silicon/magnesium ratio)

Cassiopeia A's tail appears to be made of argon and silicon and also visible in oxygen. Argon was first detected in the crab nebula.
I'm impressed by your intuitive skills

Jac

johnnydeep · Post by **johnnydeep** » Sat Mar 05, 2022 2:02 pm

Thanks, AVAO (aka Jac). I see the clearly tail now. I was hung up on it not being visible in today's APOD (only the beginning of it is barely there that I can see) and failed to look for other images.

Ann · Post by **Ann** » Sat Mar 05, 2022 2:25 pm

AVAO wrote: ↑Sat Mar 05, 2022 11:21 am
ThanX Ann

Your reasoning seems plausible to me. Alternatively, there is also the alternative idea of "filamentary jets", whatever that might be...

Fig. 3. Supernova remnants accelerate galactic cosmic rays. Left: A composite image of the roughly 300 year old supernova remnant Cas A, which is 3.4 kpc away. It has two oppositely opposed jets, the prominent one seen pointing toward the upper left. Image credit: NASA/CXC/SAO. Right: The 960 year old Crab Nebula supernova remnant which is located at a distance of 2 kpc. This Subaru telescope image shows remarkable details of its jet in this O III image that has been scaled logarithmically to show jet details. Inset: More detailed view of the jet.
From Rudie, G.C., Fesen, R.A., Yamada, T., 2008. The Crab Nebula's dynamical age as measured from its northern filamentary jet. Mon. Not. R. Astron. Soc. 384, 1200–1206. https://doi.org/10.1111/j.1365-2966.2007.12799.x, used by permission.
https://www.sciencedirect.com/topics/ea ... rab-nebula

Source: Chandra (silicon/magnesium ratio)

Cassiopeia A's tail appears to be made of argon and silicon and also visible in oxygen. Argon was first detected in the crab nebula.
I'm impressed by your intuitive skills

Jac

Thanks, Jac!

It seems very reasonable that a jet should be involved when it comes to breaking the "cocoon" surrounding the hot gases of the supernova remnant.

After all, the pulsar in the Crab Nebula already emits some sort of a "jet" - or at least a collimated beam of light - because otherwise it wouldn't be a pulsar.

Ann

Ann · Post by **Ann** » Sat Mar 05, 2022 3:08 pm

Chris Peterson wrote: ↑Fri Mar 04, 2022 3:16 pm
De58te wrote: ↑Fri Mar 04, 2022 8:43 am
RocketRon wrote: ↑Fri Mar 04, 2022 5:24 am Big and beautiful, in a cosmic sort of way.

How big would it have appeared when first sighted here on planet Earth circa 1054 AD.
Presumably it has grown since then ?

How mysterious it must have seemed back then.
And that mysterious aspect still lingers.... ?
According to this simulation for 1054, it looked about twice the size and brightness of the full Moon.
https://en.wikipedia.org/wiki/SN_1054#/ ... aifeng.png
Our displays can only represent a very narrow range of brightnesses compared to what our eyes can see. So star charts represent brightness by size. Visually, SN 1054 was just a bright star.

That's what makes the Gaia Milky Way portrait so hard to "read". Because Gaia does not make bright stars look bigger than any other stars. All stars are the same size in Gaia images. Therefore it is next to impossible to spot individual bright stars in Gaia images, but you can see clusters.

Click to see full size image

Ann

Chris Peterson · Post by **Chris Peterson** » Sat Mar 05, 2022 3:21 pm

Ann wrote: ↑Sat Mar 05, 2022 3:08 pm
Chris Peterson wrote: ↑Fri Mar 04, 2022 3:16 pm
De58te wrote: ↑Fri Mar 04, 2022 8:43 am

According to this simulation for 1054, it looked about twice the size and brightness of the full Moon.
https://en.wikipedia.org/wiki/SN_1054#/ ... aifeng.png
Our displays can only represent a very narrow range of brightnesses compared to what our eyes can see. So star charts represent brightness by size. Visually, SN 1054 was just a bright star.
That's what makes the Gaia Milky Way portrait so hard to "read". Because Gaia does not make bright stars look bigger than any other stars. All stars are the same size in Gaia images. Therefore it is next to impossible to spot individual bright stars in Gaia images, but you can see clusters.

Gaia Milky Way annotated.png
Click to see full size image

Ann

Well, Gaia doesn't produce "images", it produces data for stars, and that data includes brightness. So the issue here isn't Gaia, but how the data is represented. There's no reason it can't be used to generate more conventional images. Indeed, one piece of software that I use draws larger diameter spots for brighter stars, and uses the Gaia release 3 catalog. That said, you're right that when a star field is displayed with a very flat brightness profile, our pattern recognition system largely fails when it comes to picking out asterisms and identifying otherwise well-known stars.

Fred the Cat · Post by **Fred the Cat** » Sun Mar 06, 2022 5:01 pm

The remnant is revealing other cosmic curiosities.

AVAO · Post by **AVAO** » Mon Mar 07, 2022 6:40 am

Fred the Cat wrote: ↑Sun Mar 06, 2022 5:01 pm The remnant is revealing other cosmic curiosities.

Thanks for the interesting link Fred. I think the cosmic heart has slight cardiac fibrillation

Starship Asterisk*

APOD: The Multiwavelength Crab (2022 Mar 04)

APOD: The Multiwavelength Crab (2022 Mar 04)

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