Astronomy and Astrophysics – Astrophysics
Scientific paper
1998-06-19
Astronomy and Astrophysics
Astrophysics
39 pages, 17 figures
Scientific paper
10.1086/300420
We have observed Proxima Centauri and Barnard's Star with Hubble Space Telescope Fine Guidance Sensor 3. Proxima Centauri exhibits small-amplitude, periodic photometric variations. Once several sources of systematic photometric error are corrected, we obtain 2 milli-magnitude internal photometric precision. We identify two distinct behavior modes over the past four years: higher amplitude, longer period; smaller amplitude, shorter period. Within the errors one period (P ~ 83d) is twice the other. Barnard's Star shows very weak evidence for periodicity on a timescale of approximately 130 days. If we interpret these periodic phenomena as rotational modulation of star spots, we identify three discrete spots on Proxima Cen and possibly one spot on Barnard's Star. We find that the disturbances change significantly on time scales as short as one rotation period.
Altena van Wm.
Benedict George F.
Duncombe Raynor L.
Franz Otto G.
Fredrick Laurence W.
No associations
LandOfFree
Photometry of Proxima Centauri and Barnard's Star Using HST Fine Guidance Sensor 3: A Search for Periodic Variations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Photometry of Proxima Centauri and Barnard's Star Using HST Fine Guidance Sensor 3: A Search for Periodic Variations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photometry of Proxima Centauri and Barnard's Star Using HST Fine Guidance Sensor 3: A Search for Periodic Variations will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-22739