APOD: The Medulla Nebula Supernova Remnant (2021 Jan 18)

[APOD Robot]

The Medulla Nebula Supernova Remnant

Explanation: What powers this unusual nebula? CTB-1 is the expanding gas shell that was left when a massive star toward the constellation of Cassiopeia exploded about 10,000 years ago. The star likely detonated when it ran out of elements, near its core, that could create stabilizing pressure with nuclear fusion. The resulting supernova remnant, nicknamed the Medulla Nebula for its brain-like shape, still glows in visible light by the heat generated by its collision with confining interstellar gas. Why the nebula also glows in X-ray light, though, remains a mystery. One hypothesis holds that an energetic pulsar was co-created that powers the nebula with a fast outwardly moving wind. Following this lead, a pulsar has recently been found in radio waves that appears to have been expelled by the supernova explosion at over 1000 kilometers per second. Although the Medulla Nebula appears as large as a full moon, it is so faint that it took 130-hours of exposure with two small telescopes in New Mexico, USA, to create the featured image.

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[DL MARTIN]

How far away is this object?

[Sa Ji Tario]

DL MARTIN, If it exploded 10,000 years ago and we see it, its distance is less than 10.00 light years (but it looks more like a jellyfish than a brain)

[neufer]

How far away is this object?

The CTB 1 supernova remnant resembles a ghostly bubble in this image, which combines new 1.5 GHz observations from the Very Large Array (orange, near center) with older observations from the Dominion Radio Astrophysical Observatory’s Canadian Galactic Plane Survey (1.42 GHz, magenta and yellow; 408 GHz, green) along with infrared data (blue). The VLA data clearly reveal the straight, glowing trail from PSR J0002+6216 and the curved rim of the remnant’s shell. Image credit: Jayanne English, University of Manitoba / NRAO / F. Schinzel et al / DRAO / Canadian Galactic Plane Survey / NASA / IRAS.

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<<PSR J0002+6216, also dubbed the Cannonball Pulsar, is a pulsar discovered by the Einstein@Home project in 2017. It is one of the fastest moving pulsars known, and has moved 53 ly away from the location of its formation supernova, where the remaining supernova nebula, CTB 1 (Abell 85), is. Due to its speed in traversing the interstellar medium, at 1,127 km/s, it is leaving a 13 ly long wake tail. The pulsar is currently 6,500 ly away in the Cassiopeia constellation. The star rotates at a rate of 8.7 times a second.>>

[Ann]

How far away is this object?

Observations using the Very Large Array (orange) reveal the needle-like trail of pulsar J0002+6216 outside the shell of its supernova remnant, shown in image from the Canadian Galactic Plane Survey. The pulsar escaped the remnant some 5,000 years after the supernova explosion.

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<<PSR J0002+6216, also dubbed the Cannonball Pulsar, is a pulsar discovered by the Einstein@Home project in 2017. It is one of the fastest moving pulsars known, and has moved 53 ly away from the location of its formation supernova, where the remaining supernova nebula, CTB 1 (Abell 85), is. Due to its speed in traversing the interstellar medium, at 1,127 km/s, it is leaving a 13 ly long wake tail. The pulsar is currently 6,500 ly away in the Cassiopeia constellation. The star rotates at a rate of 8.7 times a second.>>

That's fascinating. (Couldn't find the Spock ears emoji.)

Ann

[neufer]

The corticobulbar tract is a white matter pathway connecting the cerebral cortex to the brainstem (the term "bulbar" referring to the brainstem). The 'bulb' is an archaic term for the medulla oblongata. In clinical usage, it includes the pons as well.

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<<The medulla oblongata or simply medulla is a long stem-like structure which makes up the lower part of the brainstem. It is anterior and partially inferior to the cerebellum. It is a cone-shaped neuronal mass responsible for autonomic (involuntary) functions, ranging from vomiting to sneezing. The medulla contains the cardiac, respiratory, vomiting and vasomotor centers, and therefore deals with the autonomic functions of breathing, heart rate and blood pressure as well as the sleep wake cycle.

The pons (Latin for "bridge") is part of the brainstem, and in humans and other bipeds lies inferior to the midbrain, superior to the medulla oblongata and anterior to the cerebellum. The pons is also called the pons Varolii ("bridge of Varolius"), after the Italian anatomist and surgeon Costanzo Varolio (1543–75). This region of the brainstem includes neural pathways and tracts that conduct signals from the brain down to the cerebellum and medulla, and tracts that carry the sensory signals up into the thalamus.

Both lampreys and hagfish possess a fully developed medulla oblongata. Since these are both very similar to early agnathans, it has been suggested that the medulla evolved in these early fish, approximately 505 million years ago. The status of the medulla as part of the primordial reptilian brain is confirmed by its disproportionate size in modern reptiles such as the crocodile, alligator, and monitor lizard.

The pons first evolved as an offshoot of the medullary reticular formation. Since lampreys possess a pons, it has been argued that it must have evolved as a region distinct from the medulla by the time the first agnathans appeared, 505 million years ago.>>

[starsurfer]

When this nebula was first discovered, it was thought to be a planetary nebula and catalogued as Abell 85. Another funny story, when the planetary nebula Abell 21 was first discovered, it was thought of as a supernova remnant.

[orin stepanek]

medulla? I'd call it the Doggie Nebula!!

[Chris Peterson]

DL MARTIN, If it exploded 10,000 years ago and we see it, its distance is less than 10.00 light years (but it looks more like a jellyfish than a brain)

There is no relationship between when it exploded and its distance. When we say it exploded 10,000 years ago, what we mean is that we're seeing the object at an apparent age of 10,000 years. That would be true if it were 1 light year away or a million light years away.

[neufer]

Click to play embedded YouTube video.

<<The medulla oblongata or simply medulla is a long stem-like structure which makes up the lower part of the brainstem. It is anterior and partially inferior to the cerebellum. It is a cone-shaped neuronal mass responsible for autonomic (involuntary) functions, ranging from vomiting to sneezing. The medulla contains the cardiac, respiratory, vomiting and vasomotor centers, and therefore deals with the autonomic functions of breathing, heart rate and blood pressure as well as the sleep wake cycle.>>

[Cousin Ricky]

Does anyone know why the oxygen (blue) is concentrated toward the lower left?

[Chris Peterson]

Does anyone know why the oxygen (blue) is concentrated toward the lower left?

We aren't necessarily seeing more oxygen in that region. We could simply be seeing it because that's where it is most strongly ionized, which would be a consequence of the distribution of hot stars that provide the ionizing radiation.

(Not saying this is the explanation, only that it's a factor to consider.)

[Cousin Ricky]

Does anyone know why the oxygen (blue) is concentrated toward the lower left?

We aren't necessarily seeing more oxygen in that region. We could simply be seeing it because that's where it is most strongly ionized, which would be a consequence of the distribution of hot stars that provide the ionizing radiation.

(Not saying this is the explanation, only that it's a factor to consider.)

Thanks!

[Fred the Cat]

Obviously for Linus the Great Pumpkin is finally found!

[johnnydeep]

Does anyone know why the oxygen (blue) is concentrated toward the lower left?

We aren't necessarily seeing more oxygen in that region. We could simply be seeing it because that's where it is most strongly ionized, which would be a consequence of the distribution of hot stars that provide the ionizing radiation.

(Not saying this is the explanation, only that it's a factor to consider.)

Thanks!

Hmm. Assuming the orientation is the same, if you look at neufer's post with the pic of the "cannonball pulsar" trail, it was ejected in the direction of the blue ionization in this APOD pic. Coincidence? Of course, if the orientation isn't the same, this theory evaporates.

[johnnydeep]

In view of neufer's brain anatomy post, this nebula is much more aptly names the Cerebellum Nebula:

Click to view full size image

Or even the Mushroom Nebula:

The Mushroom Nebula

[DL MARTIN]

Just when I think I've got things figured out, along comes Chris Peterson. Thanks to everyone for participating. You're opening my eyes wider everyday.

[VictorBorun]

Click to view full size image

Do I get it right: the so called "cannonball' pulsar was kicked off the site of the Supernova at 1127 km/s (or 3.76 ly/ky) and afterwards crossed the shock front of the Supernova remnant.
It is now 53 ly from that point and has 13 ly long wake tail outside the shock front of the Supernova remnant.
And presumably 40 ly long wake tail inside the Supernova remnant.

There must be a counterpart somewhere? If it's lighter than the cannoball pulsar then it must now be even further from the point of the Supernova explosion?

Here I rotated X-ray by 197,7 degree counterclockwise to overlay on the posted pic:

Correction. Overlay is radio, not Xray

[neufer]

Click to view full size image

Do I get it right: the so called "cannonball' pulsar was kicked off the site of the Supernova at 1127 km/s (or 3.76 ly/ky) and afterwards crossed the shock front of the Supernova remnant.
It is now 53 ly from that point and has 13 ly long wake tail outside the shock front of the Supernova remnant.
And presumably 40 ly long wake tail inside the Supernova remnant.

There must be a counterpart somewhere? If it's lighter than the cannoball pulsar then it must now be even further from the point of the Supernova explosion?

Here I rotated X-ray by 197,7 degree counterclockwise to overlay on the posted pic:

I agree.

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<<In the dramatic false-color radio images above, captured by the Canadian Galactic Plane Survey (background) and the Very Large Array (zoomed-in inset), a pulsar — a rapidly spinning, magnetized neutron star — is seen plunging out of a supernova remnant and taking off into interstellar space. The green cross marks the center of the supernova remnant CTB 1, and the green circle marks the location of the pulsar PSR J0002+6216. The tail of radio-emitting gas extending behind the pulsar toward the nebula is a dead giveaway to this object’s origin: the pulsar was likely born from the very same supernova explosion that produced the remnant. Supernova explosions don’t have perfect symmetry, and the pulsar likely received a natal kick that sent it tearing away from its birthplace at tremendous speeds, causing it to eventually overtake the expanding shell of gas and dust. In a recent study led by Frank Schinzel (National Radio Astronomy Observatory), a team of scientists presents and discusses the evidence that this runaway pulsar came from CTB 1.>>

[neufer]

Click to view full size image

...the so called "cannonball' pulsar was kicked off the site of the Supernova at 1127 km/s (or 3.76 ly/ky) and afterwards crossed the shock front of the Supernova remnant.

It is now 53 ly from that point and has 13 ly long wake tail outside the shock front of the Supernova remnant.
And presumably 40 ly long wake tail inside the Supernova remnant.

There must be a counterpart somewhere? If it's lighter than the cannonball pulsar then it must now be even further from the point of the Supernova explosion?

Here I rotated X-ray by 197,7 degree counterclockwise to overlay on the posted pic:

Correction. Overlay is radio, not Xray

Kelvin–Helmholtz instability occurs when there is velocity shear in a single continuous fluid, or additionally where there is a velocity difference across the interface between two fluids. A common example is seen when wind blows across a water surface; the instability constant manifests as waves.

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I'm guessing that the swept back "onion" ends of the Medulla Nebula Supernova Remnant are due to (Newton's third law) recoil kickback from the cannonball pulsar and that all that fancy fluted ribbing (so noticeable in the APOD) is due to "flag flapping" Kelvin–Helmholtz instability from the backward motion.

[Sa Ji Tario]

Chris, I certainly was quick to comment

[johnnydeep]

Click to view full size image

Do I get it right: the so called "cannonball' pulsar was kicked off the site of the Supernova at 1127 km/s (or 3.76 ly/ky) and afterwards crossed the shock front of the Supernova remnant.
It is now 53 ly from that point and has 13 ly long wake tail outside the shock front of the Supernova remnant.
And presumably 40 ly long wake tail inside the Supernova remnant.

There must be a counterpart somewhere? If it's lighter than the cannoball pulsar then it must now be even further from the point of the Supernova explosion?

Here I rotated X-ray by 197,7 degree counterclockwise to overlay on the posted pic:

Correction. Overlay is radio, not Xray

I have to grudgingly admit that your overlapping of the two images is probably correct, which, sadly, blows my theory about the blue glow being due to the pulsar passing that way out of the water.

EDIT: although...the blue glow is now directly opposite the cannonball, so perhaps there is some causal relationship after all!

[VictorBorun]

Click to view full size image

what my mind makes of the pic is a New Year Tree ball with an opening around the string that is the trail behind the cannonball pulsar.
Can it really have created a circle ridge, like in impact crater on the Moon, except this time the impact shoots from within the sphere?
Ant there are other circus structures looming above this SN remnant surface, too