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Using the EXOplanet Transit Interpretation Code (EXOTIC), we reduced 52 sets of images of WASP-104 b, a Hot Jupiter-class exoplanet orbiting WASP-104, in order to obtain an updated mid-transit time (ephemeris) and orbital period for the planet. We performed this reduction on images taken with a 6-inch telescope of the Center for Astrophysics | Harvard & Smithsonian MicroObservatory. Of the reduced light curves, 13 were of sufficient accuracy to be used in updating the ephemerides for WASP-104b, meeting or exceeding the three-sigma standard for determining a significant detection. Our final mid-transit value was 2457805.170208 ± 0.000036 BJD_TBD and the final period value was 1.75540644 ± 0.00000016 days. The true significance of our results is in their derivation from image sets gathered over time by a small, ground-based telescope as part of the Exoplanet Watch citizen science initiative, and their competitive results to an ephemeris generated from data gathered by the TESS telescope. We use these results to further show how such techniques can be employed by amateur astronomers and citizen scientists to maximize the efficacy of larger telescopes by reducing the use of expensive observation time. The work done in the paper was accomplished as part of the first fully online Course-Based Undergraduate Research Experience (CURE) for astronomy majors in the only online Bachelor of Science program in Astronomical and Planetary Sciences.
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14 New Light Curves and an Updated Ephemeris for the Hot Jupiter HAT-P-54 b
Here we present an analysis of 14 transit light curves of the hot Jupiter HAT-P-54 b. Thirteen of our datasets were obtained with the 6-inch MicroObservatory telescope, Cecilia, and one was measured with the 61-inch Kuiper Telescope. We used the EXOplanet Transit Interpretation Code (EXOTIC) to reduce 49 datasets in order to update the planet’s ephemeris to a mid-transit time of 2460216.95257 ± 0.00022 BJD_TBD and an updated orbital period of 3.79985363 ± 0.00000037 days. These results improve the mid-transit uncertainty by 70.27% from the most recent ephemeris update. The updated mid-transit time can help to ensure the efficient use of expensive, large ground- and space-based telescope missions in the future. This result demonstrates that amateur astronomers and citizen scientists can provide meaningful, cost-efficient, crowd-sourcing observations using ground-based telescopes to further refine current mid-transit times and orbital periods.
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- Award ID(s):
- 2121225
- PAR ID:
- 10543528
- Publisher / Repository:
- JAAVSO
- Date Published:
- Journal Name:
- The journal of the American Association of Variable Star Observers
- Volume:
- 52
- Issue:
- 2
- ISSN:
- 2380-3606
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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