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MPC 476 Grange Observatory

The Grange Observatory is a private, non-profit scientific institution (established in 1993, and certified with astrometry code MPC 476 in IAU Circular 25095 of May 14th, 1995) located in North-Western Italy 50 km W of Turin (details here), whose coordinates in several geodetic systems are:

ED 1950 MPC to Oct.2011 MPC Google Earth
45° 08' 31.0" N
45° 08' 31.5" N
45° 08' 31.72" N
07° 08' 29.0" E
07° 08' 29.0" E
07° 08' 26.68" E
470.0 m
449.1 m
470.0 m

The observatory with his homemade 300 mm mirror telescope is mainly devoted to astrometry, plus an off-the-shelf 140 mm astrograph at f/5.7 (from 2009), used also for astrometry and for the 0.3-m guidance or for speckle imaging, and collaborated with the International Astronomical Union's Minor Planet Center (MPC) of Cambridge, MA, U.S.A., providing data for the planetary model DE405 et seq. to NASA JPL (ICRS/J2000 standard).
Due to the poor visual seeing of the site (typically 4 arcsec star PSFs with a 30 s exposure due to persistent high altitude winds in the area), the standard photometry became the main scientific outcome of the observatory with its optical instruments, requiring astrometry as well. Currently, the HR photometry is performed with the 300 mm telescope with homemade filters for the increased light pollution level. The NEO observations are in the NEODyS website; for the comets observation instead, see MPC Electronic Circulars.
It is to be noted the observatory on 1995/1996 followed the EROS asteroid for the NEAR spacecraft, see details here

Nowadays the astrometric robotic systems made pointless the role of manned, small astrometric observatories with typically few measures per year, which had great importance in the 90's up to 2000, when the MPC codes were tri-numeral (meaning that no more than 1000 "mostly-analogic" observing centers were envisaged with the technology of that time).
As you can notice, today the MPC codes have become alphanumeric, so the modern, robotic observatories can be spotted in the final part of the MPC observatories list webpage.

The 300 mm Cassegrain telescope is self-pointed, as well as the 140 mm white astrograph, and both instruments are used for a variety of imaging and photo-astrometric programs.
The observatory produced all the used Johnson, GAIA DR2 and Sloan photometric filters.

The Grange Obs. contributes to the italian Susa Astronomy Association (AAS) for the preparation of ephemerides and for documents peer review; the skills of the observatory were important to scientifically direct a public structure on the Susa Castle, granted by the Susa Municipality since 2012 and by the AAS association fees plus 5x1000 italian tax donations. There a robotic 12 inch RC is mounted on a 10 Micron DM2000 electronic mount with a 50" LCD screen on wall showing the field. Star parties were organized there during the AAS meetings on the second Friday of the month, but not in July and August or in Italy holidays (in this case the date is put off to the next Friday), or in other occasions. From March, 2020 due to the pandemic situation, the visits are limited and conducted in accordance with sanitary rules.
Please leave your e-mail address to the AAS website to be informed about sudden virtual meeting events.

The MPC 476 Grange Observatory is not usually open to visits, since it is conceived as a research structure not suited for public's safety. Please enjoy a virtual visit thought this website, or contact AAS


grange 1995 1995 Grange Obs. view with the old "Electrim EDC 1000 HR" mono CCD, 754x488 pixels

grange 1995 1995 closeup view, with the original 80 mm visual guidescope and an Intel 486 DOS computer


© 476 Grange Observatory