A FLYING TELESCOPE
Since one has to travel to occultations rather than wait for them to arrive at the front door, it is important to have a system that can travel well. Many of my flights take place on small aircraft such as Continental Airlines Embraer regional jets which have little room underneath the seats as well as the overhead compartment. A design was needed that would work within the current aircraft limitations both for weight, size and number of allowable pieces as well as be accommodating to airport security.
In 2005 I requested Kurt Maurer of League City, Texas to design a modification to my portable occultation gear so that it would be more portable and provide greater ease in setup and stability. The design described below for the mount and finder is Kurt’s creation. I use a Meade 2045D telescope which is no longer being manufactured. This is a 4-inch aperture scope that, when coupled with a video camera and image intensifier, is capable of recording asteorid occultations of 12th magnitude stars depending on the sky conditions.
Kurt used wood in order to create a lightweight folded base that could be set up and aligned to most common latitudes. In addition he modified a right angle 9×60 AstroSystems finder scope to replace the horrible standard straight through view finder that came with my Meade 2045D. Then, the steel legs were replaced with hollow aluminum legs that were lighter and stronger. The design is illustrated in detail below.
In order to complete the setup, occultations are actually recorded using a camcorder, image instensifer and camera as described elsewhere on this site. The biggest weak point continues to be batteries. I use Supercircuits 12V rechargeable batteries but unfortunately there is no way to tell when the battery is discharged. Hence I have to carry more than one. The Meade 2045D is also run from this battery and uses a special connector that is different from that which powers the video camera (also needs a 12V source). These batteries are rather heavy and are often inspected by TSA.
The finder telescope is a crucial component. Not only does it allow more rapid polar alignment, but it permits better flexibility in finding the occultation target star. It fits inside this bracket which is hinged so that it can fold flat for packing. Note the plastic thumb screws to minimize damage to the finder tube when boresighting the finder to the scope.
In the image below you also see the dark surface of the telescope base. The hole in the center is unused. A smaller hole just below center is for the 12V battery. Just below that is the switch that permits the scope to track in either the northern or southern hemipshere.