Q&A: Chandra Mission

Q:
Could Chandra determine if there are planets around the closest (or not closest) stars? Could the heavy objects be detected around the stars, if the resolution allows, by showing an asymmetric mass distribution around that star? Could the planets surrounding a star be detected if they overlap an X-ray background (coming from other objects) so they could be seen as pieces of matter obstructing the X-ray source?

A:
It is not very likely that Chandra could determine if there are planets around the closest (or not closest) stars. Optical astronomers detect planets by carefully observing the spectrum (distribution of light with energy) of a star. If a particular feature moves around in a regular pattern, that information can be used to deduce the motion of the star, which in turn can be used to deduce the presence of an unseen planetary or brown dwarf companion. The X-ray emission from stars is highly variable, so it would be extremely difficult to deduce motion from changes in the spectra.

Such an effect of showing an asymmetric mass distribution around the star would be very small. The only hope would be to use variations in the spectrum, as discussed above.

Overlap obstruction would also have a very small effect. For a Jupiter sized source around the nearest star, any obstructing effect would be a thousand times smaller than Chandra could detect.