Observing from Afar
by Louise Good
Remote observing on the NASA IRTF accounts for over half of all observations. On-site telescope operators (pictured here) assist remote observers. The telescope is visible in the background. Photos by Karen Teramura.
At a time when air travel is becoming more expensive and unpleasant, astronomers are increasingly turning to the Internet as a way to observe without traveling. "Remote observing," as it is called, means that with the help of a telescope operator (TO) who is at the observatory, an astronomer at a distant site is able to control a telescope and its instruments over the Internet.
There are many advantages to remote observing, especially when the telescope is on a high mountain such as Mauna Kea. There is no need to acclimatize to the altitude, and no jet lag from a long trip to Hawaii. If you observe from your home institution, you can go home afterward and sleep in your own bed. Those observing from Europe can even observe during their daytime.
The fallout from 9/11 was a major impetus for the development of remote observing. Since all planes in the United States were grounded for several days, no one who was not already on Hawaii could reach Mauna Kea, so several of the observatories experimented with remote observing and found it could work.
The NASA Infrared Telescope Facility (IRTF), which is managed by IfA, has offered remote observing to all IRTF observers regularly since 2004. About 60 percent of the observing is now done remotely. While novice observers usually go to the summit to work directly with their IRTF support astronomer and to become familiar with telescope and instrument operations, experienced observers have the option of working from IfA offices in Hilo and Manoa, or from their own offices or homes on the mainland or elsewhere. In some cases, one member of an observing team will go to the telescope while the others observe from their home institution.
IRTF Support Astronomer John Rayner demonstrated remote observing on the NASA IRTF at an IfA Manoa open house.
Those who want to observe remotely on the IRTF must have the necessary hardware and software, and must arrange a test of their setup at least a month before their observing run. The observers control the instrument mounted on the telescope via a graphical user interface (GUI) and also see their data (images, spectra, or both). They can also use a GUI to make small adjustments to the telescope pointing, but larger telescope movements are done by the TO, who is responsible for the overall safety of the telescope and personnel at the summit during observing. The observer communicates with the TO using a Web-based audio-visual system such as Netmeeting (Windows) or iChat (Macintosh), but even a good audio connection, such as Skype, which enables free phone calls over the Internet, works well. Many institutions have more sophisticated teleconferencing systems, such as a PolyCom ViewStation, and these are used, too. Regular telephone connections are used only to sort out Internet connection difficulties.
Other observatories on Mauna Kea also use remote observing extensively. Most of the astronomers who use the two Keck telescopes do so from a remote control room at Keck headquarters in Kamuela. Observers on the UH 2.2-meter telescope often spend the night in the remote observing room at IfA Manoa. The Faulkes and Pan-STARRS-1 telescopes on Haleakala have been designed to be used remotely rather than by an observer present at the observatory.
There is also another mode of observing called "queued observing" (also known as "service observing") in which observatory personnel take the data for the scientists who proposed the project and send it to them, just as is done by space observatories such as the Hubble Space Telescope. Some observatories on Mauna Kea, notably the Canada-France-Hawaii Telescope, now use queued observing for a significant portion of their observing time because it makes for highly efficient use of the telescope. With queued observing, authors of highly rated telescope proposals--those near the beginning of the queue--no longer have to worry about not receiving their data because of cloudy conditions on their designated nights. Instead, the observatory personnel take the data for the next observing program in the queue on the next clear night. Queued observing also works well for projects that require a short period of time each night for many nights.