|
No telescope or data processing system is perfect, and sometimes, meteors or satellites come into the telescope's field of view. The pictures below show a few of these "artifacts" - mistakes and surprises in the data. The Navigation tool does not correctly show the artifacts. To learn more about how the SDSS collects and processes data, see the
About SDSS section.
|
The red 'ghost' is the result of light from a nearby very bright star
reflected inside the telescope. Even though such reflections are quite
weak, for very bright sources they still cause such artifacts to be detected.
|
The blue 'ghost' is the result of light from a nearby very bright star
reflected inside the telescope. It is blue, because it was reflected onto
the detector with the blue filter.
|
A wobbling satellite on a low-earth orbit. The varying
intensity of the light is due to the rotation of the satellite.
|
Bright meteor captured in the act of burning up in the earth's atmosphere.
The trail is colored green because the image of the meteor was captured in
only one of the 5 SDSS filters.
|
A wobbling satellite on a low-earth orbit. The varying
intensity of the light is due to the rotation of the satellite.
It has crossed the telescope field in a very short time, and it is
red because its path fell on the detector with the red filter, not
that the satellite is red itself.
|
Each bright star appears as a tilted 'cross' on the image. This pattern
is called a 'diffraction spike', and is due to light scattered on the four
beams that hold the secondary mirror of the telescope in place.
|
|
|
|
Each star, however bright, is still point-like. They
only appear to be extended, with a `halo' because of the scattered light
inside the telescope.
The vertical and horizontal faint stripes are due to
the `bleeding' of charge inside the detector. On the raw images these were
much stronger, but our software has successfully removed most of this effect. |
|
|
