<p>Your teacher means that when you look at the light from a star in the data from a space-based photometry mission like Kepler or TESS, you cannot be immediately sure that any variability seen is from the main target of interest or from a contaminating object that is close to it along the same line of sight.</p>
<p>For example, the characteristic transit signal of an exoplanet can be reproduced by an eclipsing stellar binary system that is seen almost along the same line of sight. Because the pixel sizes of the space missions are large, their angular resolutions are poor (Though not as poor as 1 degree? The angular resolution of TESS is about 1 arcminute.) there can be <em>many</em> other stellar light sources blended into the image of the main target of interest. These could be referred to as &quot;contaminating objects&quot;.</p>

CC BY-SA 4.0
2022-10-04T05:27:25.620Z
Thank you very much
Elena Greg
CC BY-SA 4.0
2022-10-03T21:04:00.777Z
2022-10-04T06:54:11.080Z
2022-10-04T06:54:11.080Z
ProfRob
<p>I do not have a source for this statement. A teacher just said it. Could you tell me what 'a contamination problem' mean? He explained that 'stellar images from a space-based photometry data have angular sizes of the order of 1 degree'. Thank you</p>

CC BY-SA 4.0
2022-10-03T13:49:42.023Z
I think for this type of question you'd have far more success asking the teacher himself.
antlersoft
<photometry><satellite>
Contamination problem data
Elena Greg
# Contamination problem data

(Asked by: username_0 on 2022-10-03)

I do not have a source for this statement. A teacher just said it. Could you tell me what 'a contamination problem' mean? He explained that 'stellar images from a space-based photometry data have angular sizes of the order of 1 degree'. Thank you

**Tags:** photometry, satellite
> **Comments:**
> **username_1**: I think for this type of question you'd have far more success asking the teacher himself.  

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## 1 answers

### Answer by username_2 on 2022-10-03. Score: 5 | Accepted answer

Your teacher means that when you look at the light from a star in the data from a space-based photometry mission like Kepler or TESS, you cannot be immediately sure that any variability seen is from the main target of interest or from a contaminating object that is close to it along the same line of sight.

For example, the characteristic transit signal of an exoplanet can be reproduced by an eclipsing stellar binary system that is seen almost along the same line of sight. Because the pixel sizes of the space missions are large, their angular resolutions are poor (Though not as poor as 1 degree? The angular resolution of TESS is about 1 arcminute.) there can be *many* other stellar light sources blended into the image of the main target of interest. These could be referred to as "contaminating objects".

> **Comments:**
> **username_0**: Thank you very much  

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