Alert Notice 571: Observations Requested of Exoplanet Proxima Centauri b

March 16, 2017: Dr. Karen Collins (Vanderbilt University) has requested ground-based, follow-up observations of recently discovered exoplanet Proxima Centauri b. This exoplanet is a suspected Earth-size planet orbiting in the habitable zone of our nearest stellar neighbor, Proxima Centauri (V645 Cen). There exists a rough ephemeris of this target based on radial velocity measurements, so the predicted mid-transit times can vary +/- 6 hours. Therefore, it is requested that observations be as long as possible. The expected duration of the transit is less than two hours long. The transit depth is expected to be 5 mmag. However, because Proxima Centauri itself is a flare star, there may be large variations in the light curve.

These observations are most suitable for those with prior experience conducting exoplanet observing.

The Southern hemisphere target Proxima Centauri has a magnitude range of 11.1 - 11.3 V.

Please contact Dennis Conti, AAVSO’s Exoplanet Section Chair, at if you are interested in participating in such observations and would like the predicted transit times, or if you have any further questions.

Coordinates for Proxima Centauri (V645 Cen): R.A. 14 29 42.95  Dec. -62 40 46.2  (2000.0)

Charts: Charts with a comparison star sequence for Proxima Centauri may be created using the AAVSO Variable Star Plotter (VSP).

This campaign is being monitored on the AAVSO Observing Campaigns webpage.

This AAVSO Alert Notice was compiled by Elizabeth O. Waagen from material supplied by Dr. Dennis Conti.



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