First introduced in 2014, the Celestron Rowe-Ackermann Schmidt Astrographic (RASA) telescope has an 11″ aperture and a fast f/2.2 system. This very popular instrument offers astrophotographers a way of obtaining wide-field imaging in a fraction of the time, even without the use of an autoguider.
Celestron has now announced a bigger brother to the 11″ model – the RASA 36 – a 14″/36cm aperture version. Designed and introduced as cost-effective optical system for space surveillance, Space Situational Awareness (SSA;) advanced wide field astroimaging, and other scientific applications, it offers unprecedented value in aperture, speed, field of view, and optical performance. The RASA design has a convenient external prime-focus image capture location with a flat focal plane, providing small spot sizes to the edge of a wide field. The result is images free of optical defects like field curvature, off-axis coma, and astigmatism.
The 36 cm aperture version is the largest RASA that Celestron manufactures. This astrograph is the biggest and fastest (f/2.2) optical instrument of its kind available “off-the-shelf.” Unlike most telescopes, which only focus visible light (400-700 nm), the RASA 36 cm focuses an extended spectral range (400-900 nm), allowing a brighter signal to be detected by a camera sensor. The RASA 36 cm also features a redesigned focus system, which ensures easy and stable focusing.
The RASA 36 cm’s ample back-focus distance (77.5 mm) accommodates a wide variety of imaging sensors. A custom camera adaptor can be added for a field of view up to 4.4 degrees.
Since the USSR launched the Sputnik satellite in 1957, we have relied on earth-orbiting satellites to play an ever-increasing role in global communications. Today, thousands of satellites and hundreds of thousands of pieces of “space junk” now orbit our planet Earth.
It is a sobering thought that just one day, one stray piece of space junk could damage crucial satellites and disrupt communications on a worldwide scale. The field of Space Situational Awareness (SSA) is devoted to monitoring the space environment and protecting our satellites from debris by detecting and mapping space junk in orbit. In no small way, SSA makes our globally connected way of life possible.
In 2015, SSA professionals announced that Celestron’s original 11″ Rowe-Ackermann Schmidt Astrograph (RASA) is an ideal instrument for SSA applications. Its fast focal ratio and wide field of view allow it to detect even small pieces of space junk traveling at extraordinarily high rates of speed. Currently, there are dozens of RASA telescopes in use around the world every night scanning the skies to protect our artificial satellites at a fraction of the cost of other systems.
Celestron’s team approached SSA experts to collaborate on an even better telescope to meet this important need. The result is the RASA 36. Assembled at our Torrance, California, headquarters from start to finish, this ultra-precise optical instrument can detect individual pieces of debris measuring less than 1 metre in size.
Our in-house team of optical experts has worked round-the-clock for months to produce RASA 36 telescopes to meet overwhelming demand from SSA organizations.
Now, we’re prepared to make this incredible telescope available for another application: advanced astroimaging – from imaging large nebulae, comets, exo-planet searches, wide-field surveys and much more.
|Optical Design||Rowe-Ackermann Schmidt Astrograph|
|Focal Length||790mm (31.1″)|
|Central obstruction diameter||158mm (6.22″)(44% of aperture diameter)|
|Light Gathering Power (Compared to human eye)||2581X|
|Resolution (Rayleigh)||0.39 arc seconds|
|Resolution (Dawes)||0.36 arc seconds|
|Image circle||60.1mm (2.36″) Ø, 4.4°|
|Usable field||70mm (2.75″) Ø, 5.1°, only minimal performance loss at edge of FOV|
|Wavelength range||400 – 900 nm|
|Spot size||< 6.3 μm RMS across FOV|
|Optical coatings||Enhanced aluminium, XLT multi-coatings used throughout|
|Off-axis Illumination||83% at 30mm (1.18″) off-axis|
|Optical window||104mm (4.09″) Ø|
|Back focus with included camera adapter||55mm (2.16″)|
|Back focus from top of threaded collar||77.5mm (3.05″)|
|Optical Tube Length||1079.5mm (42.5″)|
|Optical Tube Diameter||106.4mm (16″)|
|Focuser||New focuser design, minimises focus shift|
|Optical Tube Weight||75 lbs (34.02 kg)|
|Other features||Ventilation fan, dual dovetail mounting bars|
|Included items||48mm (1.89″) camera adaptor, fan battery pack|