Galaxy firing off a Gamma Ray I believe?

https://www.legacysurvey.org//viewer/?ra=346.5446&dec=-0.8176&layer=hsc-dr2&zoom=16

This is a so called #cosmic ray.

Ine :stars::dizzy:

This is a cosmic ray hit. Nothing to do with the galaxy

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Actually, I think what you have there is a micro-meteorite, not a cosmic ray hit on the sensor. Reason:

cosmic rays tend to be uniformly intense and one pixel wide along the whole track, whereas this has variable intensity, starting “soft” and ending with a bright flash covering more than one pixel (i.e. it has been imaged)

these are cosmic rays:

Normally these are removed automatically by the image processing software, I believe, but these escaped!

EDIT: on further consideration, I am not convinced that these are cosmic rays at all. A cosmic ray would be highly unlikely to strike an image sensor in a lateral straight line like this - it would be more likely to pass straight through vertically. A stream of particles from collisions with the atmosphere might make a connected convoluted track, as I have seen elsewhere.
These all look too consistent and too well aligned with each other to be cosmic rays. I fully believe that these are micro-meteorites, tiny micron-sized specks of dust, burning up almost instantly they hit the atmosphere. The space around the Earth must be full of dust that would cause streaks like this on a very sensitive image sensor, so my money is on micro-meteorites for them all. The curly ones seen elsewhere are more likely to be the cosmic rays.

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My money is on cosmic ray – it looks too sharp for something above the atmosphere. Anything that has come through the atmosphere and optics inevitably gets blurred out, while cosmics hit the detectors directly and don’t get smeared out, so they keep their sharp edges (which is one of the ways they are detected by software!). In coadds like these, they will tend to get a tiny bit blurred by the pixel-alignment process.

I don’t think it is important one way or the other, since neither is of astronomical interest and we can never know for sure. But surely meteorites must show up in the data. I posted a bigger one earlier.

This is clearly a #cosmic ray and nothing else.

Ine :stars::dizzy:

Any idea why the cosmic rays are all aligned like that?

I wouldn’t be so sure about that, Ine - see my later comment above.

The shape of cosmic ray hits are really dependent on their energy. A low energy electron would easily look curly, but a high energy muon would likely look straight.

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