How The San Diego Astronomy Association Is Able To Explore the Cosmos From Anywhere
The San Diego Astronomy Association is dedicated to exploring the skies. With a click of a mouse they're able to download images from the far reaches of the galaxy without ever leaving their offices or home. In fact, they rarely have to actually visit the observatory - it's solar-powered, 100% autonomous, and can be completely controlled via the Internet. It's also located in the middle of the desert to avoid light pollution, but that means that while attempting to capture images of objects trillions of miles away it's constantly exposed to some of the country's most extreme weather conditions.
The observatory's location is designated as high desert, with an elevation of 3800 feet, so it experiences extreme temperature fluctuations. Summer daytime temperatures typically exceed 100 degrees Fahrenheit and, in the winter, evening lows often fall well below freezing. It is also exposed to everything from mountain thunderstorms to snowstorms and plenty of dust. Not exactly the definition of a hospitable environment for computer equipment.
When most people picture an observatory, the image in their minds is of a large building with a domed roof - much like the iconic Caltech Mt. Palomar Observatory located in north San Diego County. While some domed observatories are still being built, the modern design is a box structure with a roll off roof. This design change is for two key reasons - the first being that's extremely cost effective compared with a dome, but the second is that a large portion of today's active observatories are operated fully remotely which is supported by this new design.
The Pad 70 Observatory in Tierra Del Sol, California reflects the current thinking in observatory design and is fully robotic and remote controlled. It's located in rural San Diego county, midway between the cities of San Diego and Calexico, and just a few hundred yards from the international border. The observatory is one of a collection of small observatories built on a ten-acre compound owned and managed by the San Diego Astronomy Association (SDAA).
The Observatory's frame and panels are made up of uninsulated aluminum. Keeping the inside temperature the same as the outside temperature reduces dew formation on the instruments and allows rapid cooling of the camera sensors for image noise reduction, but it also means every piece of equipment inside is exposed to the extreme temperature swings of the surrounding desert.
A Computer That Can Take The Heat (And Cold)
Given the extreme conditions, all of the components used in the observatory are carefully chosen for reliability in addition to capabilities. John Downing is a member of the SDAA and operates the Pad 70 Observatory. He was responsible for selecting and configuring the equipment for the telescope and it's array of supporting systems.
“The observatory computing environment is quite complex with a number of subsystems that must be monitored and managed. The on-site computer must also be capable of compute intensive image processing. It's a lot to ask.”- John Downing, Pad 70 Observatory Operator for the SDAA
When John says the SDAA was asking a lot of the computer that would be installed in the observatory, he specifically means that the system had to feature:
- Fanless cooling and an ability to operate in a high dust environment.
- A wide operating temperature range.
- Core i7 computing power for complex image processing.
- Capacity for removable multi terabyte solid state storage.
- Support for USB 3.0 ( or better ) connections. The observatory uses three imaging cameras for astrophotography. One is a 35 megapixel camera with a cooled sensor. Each image is 72 megabytes and the telescope generates several hundred images each night, so rapid transmission from the camera to the PC is essential.
- A 1Gb LAN connection
- Wireless connectivity for remote operation.
- An HDMI connection for a local display.
- Support for the current version of Windows 10 Professional.
- Domestic technical support.
- And, ideally, the computer would also be domestically produced.
In the end, the OnLogic ML600G-52 Industrial Fanless Intel i7 PC fit the bill exactly. It combined the fanless and ventless reliability that the SDAA was looking for, was manufactured and supported here in the US, and it had all of the features they needed to power the observatory and supporting equipment. Because the observatory can capture as much as 5 GB of data in a single evening, they also use the ML600G-52 for on-site image processing, allowing operators to download only the desired finished images. Due to its remote location, the observatory uses the ML600's built-in Extrovert cellular LTE modem with 4G to connect to the internet and transmit image data. According to John, following installation in 2017, the ML600 has been running flawlessly non-stop.
“The right PC hardware is critical to proper operation of the observatory. After an extensive search, we chose OnLogic as our hardware vendor. Even though this was a small order from a new customer, we were treated as if we were OnLogic's largest and most important customer. That’s a great company culture!”- John Downing, Pad 70 Observatory Operator for the SDAA