![leostar 2 leostar 2](http://horizonaarc.com/images/kc2017/kc2017small.jpg)
and consists of an Athena-3 Single Board Computer, an RCC5 module, an FMC-Gen3 192 gigabyte solid state recorder (SSR), a low voltage power supply, and other ancillary components. The DHU is manufactured by SEAKR Engineering, Inc. The TESS Data Handling Unit (DHU) provides the hardware, software, and firmware for camera control, on-board data processing, data storage, spacecraft avionics, and ground communications. TESS CCD mosaic and focal plane electronics with frame store regions covered (right). TESS CCD mosaic in mounting bracket (left). The four TESS cameras are bolted to a common plate such that their FOV's are aligned to form a total simultaneous FOV of 24x96 degrees.
#Leostar 2 serial
The electronics transmit digitized data over a serial LVDS link to the Data Handling Unit. The detector electronics consist of two compact double-sided printed circuit boards seated beneath the CCD focal plane.
![leostar 2 leostar 2](https://cdn.w600.comps.canstockphoto.com/wall-calendar-for-august-2020-year-eps-vectors_csp73489835.jpg)
The detectors are read out at 625 kHz with <10 e- read noise. The four CCDs in each array are separated by 2mm and create an effective 4096 x 4096 pixel detector that is operated at -75 degrees C to reduce dark current. The deep-depletion, frame-transfer CCDs consist of a 2048 x 2048 imaging array and a 2048 x 2048 frame-store region (for rapid shutterless readout 4 ms) with 15 x 15 micron pixels. Each CCD array contains four back-illuminated MIT/Lincoln Laboratory CCID-80 devices. The detector assembly in each camera consists of a focal plane CCD array and associated electronics. Along with an internal stray light baffle, each lens assembly aperture is equipped with a hood to reduce scattered light from the Earth and Moon. This corresponds to 1 detector pixel or 21 arcseconds (approx. Operating at nominal focus and a flight temperature of -75 degrees C, the 50% ensquared-energy half-width is 15 micron averaged over the FOV. The lens assemblies were designed for consistent image spot size across the field-of-view (FOV) and to produce under-sampled images similar to Kepler. Each camera forms a 24x24 un-vignetted image on the detector in its focal plane. All optical elements have antireflection coatings and one element has a long-pass filter coating to enforce a short-wavelength cutoff at 600 nm in the TESS bandpass. The lens assembly has a 10.5 cm diameter entrance pupil and a focal ratio f/1.4. The lens assembly is a custom design housing seven lenses mounted into two separate aluminum barrels that are fastened together. Each camera consists of a CCD detector assembly, a lens assembly, and a lens hood. An overview of the FOV coverage and observing strategy for the mission can be found in the Operations page. TESS is equipped with four identical refractive cameras with a combined field-of-view (FOV) of 24x96 degrees (known as an observing sector). The spacecraft provides power (via two deployable solar arrays), attitude control, data storage, and communications/transmission.Īrtist's conception of the TESS spacecraft and payload. The payload is coupled to the spacecraft, an NGIS LEOStar-2/750 satellite bus. The TESS payload has a single instrument, a camera suite composed of 4 wide field-of-view optical cameras and their associated hoods, mount, sun shield, and Data Handling Unit (DHU). The TESS observatory consists of the spacecraft and the payload.