APOD: Supernova Remnant CTA 1 (2024 Aug 23)

[APOD Robot]

Supernova Remnant CTA 1

Explanation: There is a quiet pulsar at the heart of CTA 1. The supernova remnant was discovered as a source of emission at radio wavelengths by astronomers in 1960 and since identified as the result of the death explosion of a massive star. But no radio pulses were detected from the expected pulsar, the rotating neutron star remnant of the massive star's collapsed core. Seen about 10,000 years after the initial supernova explosion, the interstellar debris cloud is faint at optical wavelengths. CTA 1's visible wavelength emission from still expanding shock fronts is revealed in this deep telescopic image, a frame that spans about 2 degrees across a starfield in the northern constellation of Cepheus. While no pulsar has since been found at radio wavelengths, in 2008 the Fermi Gamma-ray Space Telescope detected pulsed emission from CTA 1, identifying the supernova remnant's rotating neutron star. The source has been recognized as the first in a growing class of pulsars that are quiet at radio wavelengths but pulse in high-energy gamma-rays.

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[tmbruner@midco.net]

Interesting illusion if you look at with your red/blue glasses.

[Christian G.]

Remnants, always remnants… When do we get to see an actual supernova?

[Chris Peterson]

Remnants, always remnants… When do we get to see an actual supernova?

Not sure what you mean. We see supernovas all the time. Do you mean nearby? The last one we saw in our own galaxy was in 1604. We're due.
_

[Christian G.]

Remnants, always remnants… When do we get to see an actual supernova?

Not sure what you mean. We see supernovas all the time. Do you mean nearby? The last one we saw in our own galaxy was in 1604. We're due.
_
sn2023ixf_20230523.jpg

Yes, I meant seeing one nearby with our own eyes. Must see this once in my lifetime!
(I remember your two images "evolution of a supernova" in M101, that was fascinating)

[AVAO]

Remnants, always remnants… When do we get to see an actual supernova?

Not sure what you mean. We see supernovas all the time. Do you mean nearby? The last one we saw in our own galaxy was in 1604. We're due.
_
sn2023ixf_20230523.jpg

Yes, I meant seeing one nearby with our own eyes. Must see this once in my lifetime!
(I remember your two images "evolution of a supernova" in M101, that was fascinating)

Well, it depends a bit on your age and your telescope and primarily on how much patience and imagination you have ,-)
SN 1987A in the LMC is in our cosmic "neighborhood".

Click to view full size image

Credits Video NASA, ESA, Robert P. Kirshner (CfA, Moore Foundation), Peter Challis (CfA)

Click to view full size image

original data: NASA/ESA (HST) jac berne (flickr)

Click to view full size image

original data: NASA/ESA/CSA WEBBLE (HST/JWST) jac berne (flickr)

[Ann]

Remnants, always remnants… When do we get to see an actual supernova?

Not sure what you mean. We see supernovas all the time. Do you mean nearby? The last one we saw in our own galaxy was in 1604. We're due.
_

Click to view full size image

Great picture, Chris!

Ann

[Ann]

Not sure what you mean. We see supernovas all the time. Do you mean nearby? The last one we saw in our own galaxy was in 1604. We're due.
_
sn2023ixf_20230523.jpg

Yes, I meant seeing one nearby with our own eyes. Must see this once in my lifetime!
(I remember your two images "evolution of a supernova" in M101, that was fascinating)

Well, it depends a bit on your age and your telescope and primarily on how much patience and imagination you have ,-)
SN 1987A in the LMC is in our cosmic "neighborhood".

Click to view full size image

Credits Video NASA, ESA, Robert P. Kirshner (CfA, Moore Foundation), Peter Challis (CfA)

Click to view full size image

original data: NASA/ESA (HST) jac berne (flickr)

Click to view full size image

original data: NASA/ESA/CSA WEBBLE (HST/JWST) jac berne (flickr)

Great time lapse, Jac!

Ann

[johnnydeep]

I find it interesting that in the last link is this bit:

https://www.nasa.gov/centers-and-facili ... y%20minute

Fermi’s Large Area Telescope scans the entire sky every three hours and detects photons with energies ranging from 20 million to more than 300 billion times the energy of visible light. The instrument sees about one gamma ray every minute from CTA 1, enough for scientists to piece together the neutron star’s pulsing behavior, its rotation period, and the rate at which it is slowing down.

How is that possible? It sees only one gamma ray/photon every 60 seconds, yet is still able to deduce a very accurate 316.86 millisecond rotation rate?

[AVAO]

Supernova Remnant CTA 1

Explanation: There is a quiet pulsar at the heart of CTA 1. The supernova remnant was discovered as a source of emission at radio wavelengths by astronomers in 1960 and since identified as the result of the death explosion of a massive star. But no radio pulses were detected from the expected pulsar, the rotating neutron star remnant of the massive star's collapsed core. Seen about 10,000 years after the initial supernova explosion, the interstellar debris cloud is faint at optical wavelengths. CTA 1's visible wavelength emission from still expanding shock fronts is revealed in this deep telescopic image, a frame that spans about 2 degrees across a starfield in the northern constellation of Cepheus. While no pulsar has since been found at radio wavelengths, in 2008 the Fermi Gamma-ray Space Telescope detected pulsed emission from CTA 1, identifying the supernova remnant's rotating neutron star. The source has been recognized as the first in a growing class of pulsars that are quiet at radio wavelengths but pulse in high-energy gamma-rays.

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Nice PLN inside.
...it almost looks like SNR and PLN are interacting...

Click to view full size image

https://www.astrobin.com/9fcwt7/
biggg: https://www.astrobin.com/9fcwt7/#rB
Caldwell 2 (NGC 40) & CTA 1 SNR
Copyrights: Mathieu Guinot

[Keyman]

Interesting illusion if you look at with your red/blue glasses.

I did reach into my drawer to pull them out when I first saw this.

[Ann]

Supernova Remnant CTA 1

Explanation: There is a quiet pulsar at the heart of CTA 1. The supernova remnant was discovered as a source of emission at radio wavelengths by astronomers in 1960 and since identified as the result of the death explosion of a massive star. But no radio pulses were detected from the expected pulsar, the rotating neutron star remnant of the massive star's collapsed core. Seen about 10,000 years after the initial supernova explosion, the interstellar debris cloud is faint at optical wavelengths. CTA 1's visible wavelength emission from still expanding shock fronts is revealed in this deep telescopic image, a frame that spans about 2 degrees across a starfield in the northern constellation of Cepheus. While no pulsar has since been found at radio wavelengths, in 2008 the Fermi Gamma-ray Space Telescope detected pulsed emission from CTA 1, identifying the supernova remnant's rotating neutron star. The source has been recognized as the first in a growing class of pulsars that are quiet at radio wavelengths but pulse in high-energy gamma-rays.

<< Previous APOD

This Day in APOD

Next APOD >>

Nice PLN inside.
...it almost looks like SNR and PLN are interacting...

Click to view full size image

https://www.astrobin.com/9fcwt7/
biggg: https://www.astrobin.com/9fcwt7/#rB
Caldwell 2 (NGC 40) & CTA 1 SNR
Copyrights: Mathieu Guinot

Fascinating, Jac! I guess that the PLN and the SNR could be interacting, if they are close enough to be "touching".

Planetary nebula NGC 40, with supernova remnant in the background or foreground. Or are they interacting? Credit: Mark Hanson

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I can't find the PLN in the APOD, however. Where in the APOD is it?

As for the APOD, I keep seeing a creature in it. The very elongated blue feature at upper left would be its head, and the shape to its lower right would be its body.

So the question is not, What do you see in the clouds, Charlie Brown?

Ducky and horsies. Credit: roberthmyers33

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Credit: Charles M. Schulz

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The real question should be, What do you see in CTA supernova remnant, Charlie Brown? A ducky or a horsie?

I would go for a horsie. But I don't know. Maybe possibly a dragon?

Ann

[AVAO]

[...]
I can't find the PLN in the APOD, however. Where in the APOD is it?
[...]

Ann

ThanX Ann 4 your exciting comments!

Jac

[VictorBorun]

I find it interesting that in the last link is this bit:

https://www.nasa.gov/centers-and-facili ... y%20minute

Fermi’s Large Area Telescope scans the entire sky every three hours and detects photons with energies ranging from 20 million to more than 300 billion times the energy of visible light. The instrument sees about one gamma ray every minute from CTA 1, enough for scientists to piece together the neutron star’s pulsing behavior, its rotation period, and the rate at which it is slowing down.

How is that possible? It sees only one gamma ray/photon every 60 seconds, yet is still able to deduce a very accurate 316.86 millisecond rotation rate?

if you happen to register a ɣ particle once in a minute, or once in 190 pulses, you need patience to accumulate those registrations.

How many depends on the precision of your registering time while radio-quiet pulsar is aiming the jet on you.
If your time error is zero, then just 3 registrations give you 2 time intervals, say of k periods and of m periods, and if you are in luck and k and m are coprime like 256 and 375, then you already know that the first of your intervals is 256 periods long, or 512, or 768, etc.

The jet may be not so narrow so the time you register a ɣ particle may leave some error for the time the pulsar was aiming at you. That's why just 3 ɣ particles will not do.

But enjoying a particle a minute you can accumulate many.

[johnnydeep]

I find it interesting that in the last link is this bit:

https://www.nasa.gov/centers-and-facili ... y%20minute

Fermi’s Large Area Telescope scans the entire sky every three hours and detects photons with energies ranging from 20 million to more than 300 billion times the energy of visible light. The instrument sees about one gamma ray every minute from CTA 1, enough for scientists to piece together the neutron star’s pulsing behavior, its rotation period, and the rate at which it is slowing down.

How is that possible? It sees only one gamma ray/photon every 60 seconds, yet is still able to deduce a very accurate 316.86 millisecond rotation rate?

if you happen to register a ɣ particle once in a minute, or once in 190 pulses, you need patience to accumulate those registrations.

How many depends on the precision of your registering time while radio-quiet pulsar is aiming the jet on you.
If your time error is zero, then just 3 registrations give you 2 time intervals, say of k periods and of m periods, and if you are in luck and k and m are coprime like 256 and 375, then you already know that the first of your intervals is 256 periods long, or 512, or 768, etc.

The jet may be not so narrow so the time you register a ɣ particle may leave some error for the time the pulsar was aiming at you. That's why just 3 ɣ particles will not do.

But enjoying a particle a minute you can accumulate many.

Thanks. I don't totally follow your math, but I guess I can see that with a high enough accuracy of the measurements, along with enough measurements, even if they happen infrequently, you can deduce the still precise yet much smaller fundamental pulse interval underlying it.