GJ 436 Extrasolar Planet Transit Campaign
Abstract:
Observations of the extrasolar planetary system around GJ 436 are requested to help explain anomalous changes in the transiting properties of a 'hot Neptune' type planet (GJ 436b). These perturbations manifest themselves in changes in the larger planet's transit properties. Specifically, the transit time, duration and amplitude may be affected. So far, only transit timing variations (changes in the transit midpoint) may have been detected. A recent paper published to ArXiv by Ribas, Font-Ribera and Beaulieu suggests that a previously undetected 5-Earth mass planet may exist elsewhere in the GJ 436 system and that its gravity may be the cause of the anomalies. If the smaller planet does exist, it would be the smallest planet yet detected in a solar system around a main sequence star. However, that is still a big if as there are possibly other astrophysical explanations as well. The theory is provocative enough that it should be checked. The key will be to get large amounts of quality data to confirm or negate this dual planet hypothesis.
Justification:
To explain anomalous changes in the transiting properties of the 'hot Neptune' type planet GJ 436b, and to confirm or negate the existence of a previously undetected 5-Earth mass planet in the GJ 436 system.
Requested Data Types:
Photometry
Targets
| Name | Magnitude | Variability Type | Photometry Notes | Spectroscopy Notes |
|---|---|---|---|---|
| GJ 436 | 10.62 | EP |
Cadence: Not Specified Precision: 100 |
Not Requested |
Spectroscopy Lines:
No spectroscopy lines provided
Photometry Filters:
No photometry filters provided
Comparison Stars:
No comparison stars provided
Co-Authorship
Observers are not eligible for co-authorship.
Additional Observer Input:
Not provided
Additional Submission Location:
Not provided
Forum URL
N/A
Notes:
Principal Investigator: Dr. Greg Laughlin; Imported Campaign (Alert Notice #370)