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Dettagli sul Grange Obs.
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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 current
45° 08' 31.0" N
45° 08' 31.5" N
45° 08' 31.8" N
07° 08' 29.0" E
07° 08' 29.0" E
07° 08' 26.7" E
470.0 m
449.1 m
512.3 m

From August 2023 the new website of the observatory shall be at this address.
The observatory with his homemade 300 mm mirror telescope and an off-the-shelf 140 mm astrograph for 30 years are mainly devoted to astrometry (i.e. the accurate measurement of Solar System's moving celestial bodies, like comets/asteroids) 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 filters for the increased light pollution level, prepared by the Grange Obs. laboratory, or GOlab.
The Grange Obs. astrometric and photometric observations of NEO asteroids are collected in the ESA funded NEODyS website; for the comets observation instead, see MPC Electronic Circulars.
It has to be noted a dedicated study was conducted in 1995-96 for improving the orbital elements of NEO asteroid (433) Eros, since it was the target of the JPL spacecraft NEAR Shoemaker (which successfully entered in orbit around it, and afterwards landed on the asteroid's surface on February 12th, 2001).

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.

After the successful collaboration with JPL, the Grange Obs. has then become a scientific start-up facility and a fundamental astronomy research center.
In particular, contacts with JPL/Caltech increased for the development of a methodology for studying the AMS 02 ISS payload position and pointing accuracy problem.

In the Astronomical Year 2009 an off-the-shelf refractor was purchased (a Vixen 'Petzval' or double-achromat astrograph of 140 mm diameter) mounted on the main instrument, substituting the original 80 mm guidescope, present up to 2015, the International Year of Light promoted by UNESCO, which kindly permitted Grange Obs. to use their logos in this website.
The Grange Obs. current instrumental layout is shown here below:


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 GOlab produced all the used Vilnius, Johnson, GAIA DR2 and Sloan photometric filters. The private observers or astronomical observatories interested to obtain certified photometric filters from the GOlab are encouraged to ask for a quotation.

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 donations. There a robotic VIS 12 inch RC with a 50" LCD screen is mounted on a 10 Micron DM2000 electronic mount. 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



click to enlarge 1995 Grange Obs. view

click to enlarge 1995 closeup view

12 inch blank's deflection: click to enlarge FEM calcs on request:
evaluation of your scope's deflections, stresses, frequencies!


Aldebaran occulted real photo: click to enlarge Ask also for your site astronomical calcs and high precision ephemerides!

Apollo Lunar Rover NASA photo Are you curious about what influences Moon/Mars robotic or human rovers locomotion and other key technologies needed?

Have a look of the Exploration Page


Sun image

Jupiter RGB

Have a look of diffraction-limited Sun imaging in UV wavelengths and RGB planets rendering!

Please click the High Resolution and the Spin-off pages

© 476 Grange Observatory