Guidelines for AAT Observers

Important changes on August 1st, 2018

Support astronomers for most observing progams will no longer be provided. Programs that were awarded time through OPTICON and NOAO and some paid time programs will have a support astronomer.

A "Must-do" Checklist

1. You must use the Visitor form to keep us informed of your plans. (Note: a Data Central account is required to access this form.)
2. All observers must read the Safety Guidelines.
3. If you have a support astronomer, make contact with your support astronomer well in advance of your run.
4. Fill out your Observer's Report Form at the end of your last night.

Support

A night assistant and technical support are always provided at the telescope. A support astronomer (only for certain programs beyond August 1st, 2018) is available to advise on your observations, and will assist at the telescope if required. He or she will usually contact you a month or so before your observing run. If you wish to contact them ahead of time, see the Schedule Notes near the bottom of the schedule for their e-mail address.

Students

The AAT strongly encourages students to attend and participate in observing runs. However, all students must be accompanied throughout by their supervisor, or a suitably-qualified colleague (postdoc-level or above). Under certain circumstances, suitably-experienced graduate students may observe on their own at the AAT, but only with the prior written permission of the SSO Director.

Observing Guidelines

• If you are observing at site, you are strongly encouraged to arrive at the telescope one day prior to your observing run. The trip from Sydney can be a long one, and may not leave sufficient time to set-up for your run if you arrive on the day your run starts.
• If your required set-up changes from that which you originally proposed, it is essential that you contact your support astronomer (see schedule), and the AAT scheduler  to inform them of the change. Significant changes made at the last minute may be difficult, or impossible, for the telescope staff to accommodate.
• 2dF observers should thoroughly familiarise themselves with the documentation available on the 2dF + AAOmega home page, which includes the 2dF Manual, Information for Observers, and a list of Frequently Asked Questions. 2dF is a very complex instrument! We have developed a "FAQ", available from the 2dF + AAOmega WWW page, and which we encourage observers to read. You should liaise with your support astronomer before your run if there is anything which is unclear. Because of the complexity of 2dF set-ups, it is essential you are ready to begin work by 4 hours before dark on the day of your run. For this reason 2dF observers must always arrive at the telescope on the day before. Many problems can be fixed if they are caught the day before observing starts!
• Every observer should fill out an Observer's Report Form towards the end of their last night. The information provided in these forms is vital to the continued improvement in the Observatory's facilities.
• Observers must also pay for their overseas telephone calls. Please settle debts with Adminstration in the AAT Reception before your departure; the AAT accepts Visa, MasterCard and Bankcard. These charges are separate from the accommodation charges payable to the ANU Lodge.

Back-up Program Considerations

All observing at the AAT is currently Classical time, there are no standby programs for bad weather, and it is up to you as the observer to make best use of less than perfect conditions when they happen. There are four weather related phenomena that might restrict or degrade observing but in which observing can continue. Unless you have a program that is unaffected (e.g. many bright targets all over the sky) or the instrument you are using is incapable of observing in the specific degraded conditions (instruments can’t be changed mid-run), you should aim to have a back-up program ready to take advantage of this time.

• Clouds: A weather allowance factor of 1.5 is built into all proposals to use the AAT, this accounts for time that is completely lost. However, it can also happen that there is thin cloud you can observe through. Brighter targets/fields are best for this.
• Poor Seeing: The median nightly seeing at the AAT is 1.6 arcseconds, and 15 % of the time it is actually better than 1.1 arcseconds. However, around 15% of nights are worse than 2.5 arcseconds, and about 1.5% are worse than 4.0 arcseconds, rarely seeing has been known to be worse than 10 arcseconds. In such conditions you may need to observe brighter targets, or avoid targets with only very faint guide stars. Depending on the instrument you might also need to reconsider what is an appropriate aperture size.
• Condensation: A combination of high humidity and low temperatures can cause condensation on the dome and/or telescope, especially if the wind is only light. If condensation builds up on the telescope observing has to stop, but the inside of the dome is air conditioned, so such instances are exceedingly rare. Condensation more easily builds up on the dome however. When this gets bad water can drip from the windscreen into the dome. In this situation, in order to protect the telescope and instrumentation the ZD allowed for observing is restricted: for the 2dF top end the limit is 40 deg, and for the other top ends it is 25 deg; the telescope must point lower in the sky than this. Single target programs are especially vulnerable to losing time in this circumstance and so you should have in mind alternate targets that will be away from the zenith.
• High Wind: Nominally the wind speed limit at the AAT for safe operation is 90 km/h. This is rarely approached, however when it is observing might be restricted to azimuthal angles pointing away from the wind direction. The 2dF top end is more susceptible to high wind than other top ends. Try and have a back-up target or field in mind that is in the opposite hemisphere to your primary.

In addition to weather, observing might also be restricted for technical reasons, such as damage to the windscreen. A good observer prepares for all eventualities. Not being able to observe your primary program can be frustrating, especially if the sky is clear! But it can also be an opportunity. Ideally you’d like to observe a different target for the same science program, but this may not always be possible. In this case test observations might be carried out for a future program, an old program completed, or something more speculative tried. The first QSO observed at the AAT was found in just such an instance! A back-up program also resulted in the first measurement of reflection from a stellar atmosphere. If you plan well, poor conditions might actually give you a great result.

Safety at the AAT

• Dome Safety: The following is excerpt is taken from the AAT Safety Guidelines which every observer will find on their desk when they arrive at the AAT. Observers must follow these guidelines at all times.
  

  Admission to areas of the AAT building above Floor 2 is allowed only with the permission of an observatory staff member. Only the current observers should be at the control room level. No-one (observers included!) may enter the dome at night without the knowledge and approval of the night assistant, whether to check the instrument or the weather etc. Everyone entering the dome at night must collect a torch/flashlight and carry it with them at all times. Anyone unfamiliar with the telescope or dome should ask for a 5 minute orientation tour. Please ensure that your colleagues appreciate these requirements.

• Bushfire Safety: Bushfires (also known as forest fires or wildfires) present a very real risk to the observatory site each summer (November to March). Visiting observers are especially at risk. Please ensure you have read the document describing Fire Procedures during Bushfire Season for Siding Spring Observatory. Bushfires can change quickly and unpredictably and so visitor familiarity with these procedures during the summer months is of paramount importance.

• Travel Safety: Visiting observers will be mentally fatigued after their final night of observing. They must account for this in their travel plans. Visitors are reminded that the Lodge has a checkout time of 2pm for night workers and that they are recommended to book an extra night to recover.

Preprints and Reprints

It is important that we maintain complete records of publications based on AAT and UKST observations. We also request an acknowledgement to the AAO in any publications which result from use of the facilities.

Visitor Instruments

Observers awarded time with a Visitor Instrument are encouraged to examine the Guidelines for Visitor Instruments to ensure their instrument arrives in time for their run to go smoothly.