Exoplanets from the Arctic: The First Wide-Field Survey at 80 Degrees North

TL;DR

This study demonstrates that deploying wide-field cameras in the Arctic's continuous winter darkness enables effective detection of transiting exoplanets around bright stars, leveraging unique polar observing conditions.

Contribution

First implementation of a wide-field exoplanet survey at 80° North, showcasing novel data reduction pipelines and photometric techniques in extreme Arctic conditions.

Findings

Achieved 1-2% photometric precision in 10s exposures.

Demonstrated stable 2-3 mmag photometry over 10-minute bins.

Estimated capability to discover several transiting exoplanets during full arctic winter.

Abstract

Located within 10 degrees of the North Pole, northern Ellesmere Island offers continuous darkness in the winter months. This capability can greatly enhance the detection efficiency of planetary transit surveys and other time domain astronomy programs. We deployed two wide-field cameras at 80 degrees North, near Eureka, Nunavut, for a 152-hour observing campaign in February 2012. The 16-megapixel-camera systems were based on commercial f/1.2 lenses with 70mm and 42mm apertures, and they continuously imaged 504 and 1,295 square degrees respectively. In total, the cameras took over 44,000 images and produced better-than-1% precision light curves for approximately 10,000 stars. We describe a new high-speed astrometric and photometric data reduction pipeline designed for the systems, test several methods for the precision flat-fielding of images from very-wide-angle cameras, and evaluate the cameras' image qualities. We achieved a scintillation-limited photometric precision of 1-2% in each 10s exposure. Binning the short exposures into 10-min chunks provided a photometric stability of 2-3 millimagnitudes, sufficient for the detection of transiting exoplanets around the bright stars targeted by our survey. We estimate that the cameras, when operated over the full arctic winter, will be capable of discovering several transiting exoplanets around bright (V<9) stars.