Exo-planets don't emit light on their own, which makes it very difficult to detect them directly. Instead we search indirectly for them by looking at the physical effect the planets have on their parent stars.
We search for exo-planets by monitoring the periodical brightness variations of the visible stars with time. When a planet passes in front of its parent star, it blocks part of the emitted starlight, which results in a dimming of the stellar brightness. The dimming can be as little as less than 1% so accurate measurements are needed. Once detected and analysed this dimming can hopefully be an exo-planet transit signal.
The Atik cameras tested in the lab.
MASCARA monitors locally the whole night sky at high cadence to search to exo-planets around the brightest stars in the sky. To do so, a MASCARA station is equipped with 5 cameras.
Each camera has a field of view of 40° x 70° on the sky. With five cameras we cover the entire sky down to airmass 2 (30°) and partially down to airmass 3.
|Atik 11000M interline||Canon wide-field lens|
|24 x 36 mm, 9 µm pixels||24 mm, f# 1.4|
The station is composed of two independent frames. The inner frame supports the cameras and the camera-enclosure. The computers for MASCARA, both the control computer and the camera computers, are placed on a platform within the inner frame. The roof and the motors actioning the roof are fixed on the outer frame.
With this configuration, MASCARA remains quite compact while minimizing vibrations due to the motion of the roof, or wind burst.
We have a timelapse movie of the integration of the MASCARA station in La Palma in October 2014.