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Wikipedia says says:

NEO Surveyorformerly called Near-Earth Object Camera (NEOCam), then NEO Surveillance Mission, is a planned space-based infrared telescope designed to survey the Solar System for potentially hazardous asteroids

and later:

The detector array is 2,048 × 2,048 pixels and will produce 82 gigabits of data per day.31

Mainzer, Amy K. (18 November 2009). NEOCam: The Near-Earth Object Camera (PDF). 2nd Small Bodies Assessment Group Meeting 18–19 November 2009 Boulder, Colorado. Archived from the original (PDF) on 24 June 2016. Retrieved 13 January 2018.

From slide 10:

NEOCam spends all of its time surveying the low elongation regions where hazardous NEOs spend most of their time (Chesley & Spahr 2003)

  • Current survey region: 40 - 125º elongation, ±45º latitude
  • Observation method: step and stare, 182 sec integration time, 30 sec slew/settle time; 4500 sq deg/day
  • 2 visits per “night”; entire search region every ~5 days for maximum efficiency at linking tracks and tracklets
  • On-sky time = >23 hrs/day

Question(s): What will NEO Surveyor do with 82 gigabits of data per day?

  1. How will it process it?
  2. What fraction will be sent to Earth,
  3. How will this data size management compare to the way TESS and GAIA do it?

Further reading:

uhoh
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  • It looks like some important design information is missing from these documents. 82 Gb is a lot more than a 4 MP sensor with a 180s integration time can delivery per day. – asdfex Jul 11 '21 at 11:58
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    @asdfex Ya I see what you mean; 2048 * 2048 * 3600 * 23 / (182+30) / 1E+09 ~1.6 Gbit/day To maintain a good dynamic range sometimes CCDs are read out many times during an exposure. I don't know what they do in this case yet, since they'll be looking for dim objects and don't really care about the bright ones unless the dim one of interest is near something bright. – uhoh Jul 11 '21 at 14:26
  • @asdfex for example the CCD's of TESS are read out every 2 seconds. See Characteristics of the TESS space telescope and scroll down to Data Handling Unit. For the 3.4- and 4.6-micron detectors in WISE it seems that it's every 1.1 seconds. Wide-field Infrared Survey Explorer Launch Presskit 2009. – uhoh Jul 11 '21 at 14:44

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