Technical Specs
The table below provides the current specifications for the ATLAS system. The final specifications will depend on too many factors to include here but include funding availability, time requirements, site considerations, etc.| Initial number of observatories/sites: | 2 |
|---|---|
| Location: | TBD - probably Hawaii or Arizona. Depends on where we can get easy permission and good power and Internet access |
| Site separation: | ~100 km |
| Number of telescopes per observatory: | 4 |
| Telescope type: | Takahashi Epsilon-250 Astrographs |
| Telescope diameter: | 25 cm |
| Total equivalent telescope diameter: | 0.5 m |
| Telescope Mount: | Astro-Physics 3600 GTO or Software Bisque Paramount ME |
| Focal length: | 0.7 m (f/2.8) |
| Individual Camera FOV: | 20 deg² |
| Total FOV: | 40 deg² |
| Survey coverage/night: | 20,000 deg² twice/night |
| Time between revisits each night: | About an hour |
| Effective PSF FWHM: | 3.8" |
| CCD: | Two Lincoln Laboratory CCID20 2k x 4k /camera |
| Pixel size: | 15 µm |
| Pixel scale: | 4.4" |
| CCD Operating Temperature: | -60 C |
| Filters: Bandpasses are designed to provide same S/N for a solar spectrum at same exposure time. |
'red' ~ SDSS g+r 'blue' ~ SDSS r+i |
| Exposure time: | 30 s |
| Readout time: | 5 s |
| Readout noise: | 10 e‾ |
| Total number of images/night: (=2 sites x 4 cameras/site x 1000 images/camera/night) |
8000 |
| Total data rate: | 80 GB/night/site (compressed) |
| Computing requirements: | 20,000 core-cycles/pixel or about four 2.2GHz 4-core computers/site |
| Saturation magnitude: | 'red' @ V~13 'blue' @ V~12.5 |
| Limiting magnitude (at SNR=5): Stationary objects Assuming solar spectrum. |
Single telescope: V=19.1 Co-added pair from one site: V=19.5 Co-added pairs from 2 sites: V=19.9 |
| Photometric accuracy: | 0.01 mag @ V~16 0.02 mag @ V~17 0.04 mag @ V~18 |
| Astrometric accuracy: | 2"/SNR, where SNR ~ 10^(8.5-0.4*mag) |
| Number of asteroid detections/night: | Up to 70,000 (i.e. 35,000 asteroids) |
| Number of detected impactors/year: | 1 |
| Impactor detection efficiency: | >60% for objects larger than about 50 meters diameter. Most of the remaining 40% are approaching from the direction of the Sun and can not be seen in the night sky. |
| Impact Warning Time: | About a week for 50 meter diameter impactor About a month for a 140m diameter impactor |
| Maximum asteroid detection distance: (assuming 0.1 albedo) |
1 meter diameter - 10 meter diameter - 100 meter diameter - |
| Construction and development cost: | About US$3M |
| Construction and development time: | About 3 years. I.e. we expect to begin surveying less than 3 years after start of funding. |
| Annual operationscost: | About US$0.5M |
| Each additional observatory/site: | About US$1M |