Bosscha Observatory is the oldest observatory in Indonesia. The observatory is located in Lembang, West Java. Bosscha Observatory was built by the Nederlandsch-Indische Sterrenkundige Vereeniging (NISV) or seemingly the Dutch Indies outer-space geek club. It took 5 years to build, from 1923-1928. 

The Bosscha observatory was built and erected with the important purpose of astronomers in the 20th century, where they realized that the clusters of stars in the sky turned out to form a system of galaxies that are bonded to each other. Well, armed with the desire to understand the structure of galactic networks which is so broad, then they not only reasonably be able to investigate if a large telescope to examine the galaxy is only centered in the northern hemisphere just like Europe and America.

Facilities

Five large telescopes were installed in Bosscha:

1. The Zeiss double refractor

This telescope is mainly used to observe visual binary stars, conduct photometric studies on eclipsing binaries, image lunar craters, observe planets (Mars, Saturn and Jupiter) and to observe comet details and other heavy bodies. The telescope has two objective lenses with a diameter of 60 cm (24 in) each and a focal length of 10.7 m (35 ft).

2. The Schmidt telescope (nicknamed: Bima Sakti telescope)

This telescope is used to study galactic structure, stellar spectra, asteroid studies, supernovae, and to photograph heavy bodies. The main lens diameter is 71.12 cm (28.00 in), the correcting bi-concave and convex lens is 50 cm (20 in) with a focal length of 2.5 m (8.2 ft). It is also equipped with a spectral prism with a prime angle of 6.10 degrees for stellar spectra, a wedge sensitometer and a film recorder.

3. The Bamberg refractor

This telescope is used to determine stellar magnitude, stellar distance, and photometric studies of eclipsing stars, solar imaging, and others. It is equipped with a photoelectric photometer a 37 cm (15 in) lens diameter and a 7 m (23 ft) meter focal length.

4. The Cassegrain GOTO

This was a gift from the Japanese government. This computer controlled telescope can automatically view objects from a database and this was the first digital telescope at Bosscha. The telescope is also equipped with a photometer and spectrometer-spectrograph.

5. The Unitron refractor

This telescope is used for observing hilal, lunar eclipse, solar eclipse and sunspot photography, and also other objects. Lens diameter is 10.2 cm (4.0 in) and a focal length of 150 cm (59 in).

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