Proposal #506

This is an amendment to Proposal 504 -- an exoplanet transit proposal to observe the HIP 41738 f. This amendment has updated information based on a "Special SG1 Observing Campaign Request" sent by Karen Collins. The goal is to collect preliminary information for a JWST proposal. There are several potential periods to examine, so as many three-hour periods of observation time over the times below will help meet the goals of this call. I will put in the details of the call in the text below. Should this proposal be accepted, I will volunteer to do the analyses of the transit data using AstroimageJ following the TFOP SG1 guidelines. I will submit the data to EXOFOP since and/or the AAVSO Exoplanet Database.

The nominal observational period (i.e., TOI 4304.55) has an ingress, midpoint, and egress at UTC 01:48, 10:48, and 19:48, respectively, on 05/08/2024. There is a 6-hour baseline uncertainty.

--Copy of SG1 Request sent by Karen Collins--

Hi SG1 northern and southern hemisphere observers,

We have a special request from Zoë de Beurs and team for observations of known planet HIP 41378​ f, which has orbital period P = 542 days. The next transit event is coming up in 2-3 days. The main goal with these observations is to prepare for a JWST proposal that would investigate this planet. Anyone who contributes useful data will be invited to join the JWST proposal and would be invited as coauthor on any resulting paper.

The target Dec is + 10, so it is observable from most observatory locations in the north and south.
RA = 08:26:27.849
Dec = +10:04:49.34

The target star is bright at V = 8.93 and the depth is 5 ppt, so most SG1 observatories can probably detect the event.

Use a red (r', R, i', I, z, Y, CBB) filter that gives the best photometric precision for your instrumentation.

Given the bright target star, you may want to offset your field to catch other bright comparison stars.

The transit duration is 19 hours, so we are hoping to detected ingress and egress independently from different observatory locations.

The timing uncertainty is +/- 6 hours due to TTVs. Since the TTF currently triggers only on nominal ingress and egress times, there are 5 different ephemerides on the TTF, each shifted by 3 hours over the +/- 6 hour range. The five ephemerides are named:

TIC 366443426.53 (TOI-4304.53) - 6 hours early ephemeris
TIC 366443426.54 (TOI-4304.54) - 3 hours early ephemeris
TIC 366443426.55 (TOI-4304.55) - nominal ephemeris
TIC 366443426.56 (TOI-4304.56) - 3 hours late ephemeris
TIC 366443426.57 (TOI-4304.57) - 6 hours late ephemeris

Three or more hours of observations over the time range below might be useful to detect or rule out an ingress or egress:
UTC 2024-05-08 04:00 through 2024-05-09 15:00