Does anyone know why the red dot doesn't appear in the red channel?




Red-Channel picture:

and now the “z” (what ever z is)-Channel


Here is the “red” dot… :slight_smile: (but why not in the red-channel if “r” stands for red)

And a second question… What could this little white point be on the other side that only appears in the green channel in an image?

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The z-channel is infrared whereas the r-channel is visible red, so z is “even redder”. This means that this object radiates mostly in infrared frequencies. Brown dwarf stars are very cold (for stars) so this could be one of them, foreground in our galaxy.

The small white pixel in the g exposure could be an asteroid in our solar system but it’s not found in the JPL Small-bodies database. It’s also not visible in an r-band exposure taken 2 minutes prior, so it would have been quite fast if it were in space. It could be a cosmic ray hitting the camera sensor. Usually they are longer streaks but this one is very “head-on”.

Just to expand on this,
“g” band here -> blue in the color images
“r” band -> green
“z” band (infrared) -> red

Ahh a very important piece of information.

So “g” in the filename does not stand for green … thank you very much.
and “r” does stand for green but not for red

then my question was stupid - because red is obviously not green :slight_smile: .