The Nassau Station Robotic Telescope Reference

How does an observing queue work?

So you've gone and submitted a well thought out proposal to the Nassau Station Robotic Telescope. What happens to it now? What's this "queue" thing? Let us explain.

I submitted a proposal....

When you submit a proposal to the telescope all of the information in that proposal is saved to a database containing everyone else's proposals. In short, all of the proposals that are in the database awaiting processing are the queue. It is from this database of proposals that we build the observing list for the telescope for a given night. So how do we pick which proposals to observe? That's a good question.

Life in the queue.

The life of a proposal in the queue is like that of a girl (or boy to be politically correct) waiting to be asked to dance at a party. All the proposals sit off together and wait and hope that the scheduling program will pick them to "dance" with tonight. The job of the scheduling program is to pick out which proposals are observed on the telescope on a particular night. There are several criteria that the scheduling program uses to pick "dance partners" for the telescope. Here's a short list of the most imporant qualities the scheduler considers:

1. If it is physically possible for the telescope to observe this proposal tonight.
2. Priority group of the user who submitted the proposal.
3. Amount of telescope time the proposal will take to complete.
4. How long the proposal has been waiting in the queue.

The first quality is the most important. The telescope obviously can not complete a proposal if the object to observe does not get above the horizon on that night or if the proposal calls for use of the spectrograph and the spectrograph is not available on that night. If there is a chance your proposal may become impossible to do in a few weeks, this may be considered as well to finish it before it becomes impossible to complete.

Second it is important to consider the priority group of the user who submitted the proposal. Preference is given in the order of Warner and Swasey Staff, Privileged Users, CWRU Astronomy Students, Hands on Universe Users, other CWRU students and staff, and the General Public. The proposals are generally approached to dance in that order. However we want to be fair so every night a minimum amount of time will be allotted to each priority group. For example about 10% of the time every night will be guaranteed for use by users classified as General Public, not to say General Public users could not take up even more time under certain circumstances.

The estimated amount of time it will take to complete the proposal plays a roll in scheduling when there may not be enough free time in one night to complete a proposal. This is important to consider when submitting a proposal. Generally proposals that require less time from the telescope will be given a better chance to be completed quicker because if you can get squeezed in edge-wise, we'll do it. For the General Public we suggest that proposals be kept under fifteen to twenty minutes in length at most and optimally under five or ten minutes in length in order to get your proposal done in a quick and timely fashion.

As said earlier, we want to be fair to everyone, so the final tie breaker for the scheduler is to consider who has been waiting in the queue the longest. It seems only fair if we have two proposals equal in everything else that the one who has been waiting to be asked to dance the longest should be given their dance first.

Tips for Cinderellas wanting to fill out their dance card.

The simple philosophy here is that every proposal gets a "dance" with the telescope eventually. How long a proposal has to wait in the queue before it gets it's chance is dependant on some factors under the control of the user making the proposal and others that are not.

Here are some general tips to consider when putting a proposal in the queue:

1. Check the physical feasibility of doing the proposal yourself before making a submission. The proposal forms will give automatic warnings if some parts of your proposal are impossible to do but they won't tell you if you will have to wait a month for your object to come out from behind the sun. Also keep an eye out for any notices that might be posted about the availiblity of instruments on a given night.
2. In particular for observations of solar-system objects (planets, asteroids, etc.) be aware of the feasibility of the telescope observing that object within a reasonable number of nights. A request for Venus might get queued, but you might end up waiting three months or more to get it done.
3. Submit several short (time-wise) proposals in place of one long proposal when ever possible. Only schedule long squences of exposures when it is absolutely necessary that the exposures all be made on the same night.
4. Be prompt and think ahead. The queue can in some instances boil down to first come, first serve so don't dawdle with getting those proposals submitted.
5. Be patient. Remember everyone gets a chance to dance.

Pumpkins at midnight?

Be calm. Be patient. Don't get discouraged. No one is turning into a pumpkin at midnight here so no worries. In some instances it may take some time to complete your proposal but we are working our hardest to get it done in a fair and efficent manner. The whole reason for scheduling from the queue is it allows us to use our telescope more efficiently than if we had a human running it and deciding what to observe. This is especially true of those short little snap-shots you may want of your favorite star cluster or planet. In a normal human run observing program you would almost never get a short proposal like that wedged in edgewise, humans are just too inefficient. So remember those tips we gave you and good luck.

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