La Silla Observatory



Re-Engineering Project:

Astronomy Operation


Prepared Olivier Hainaut 2002-03-20
Reviewed Rene Mendez
Released Jorge Melnick 2002-06-12

Revision History

0.1 2002-03-10 first draft, ohainaut
0.2 2002-04-02 2d draft, ohainaut
0.9 2002-05-11 2d includes revision, ohainaut. Includes Review Discussion
2002-05-29 added few comments from 2d round.
2002-06-12 more comments by JMelnick included




This document discusses astronomical aspects of the LSO Science Operation Department. It will eventually become part of a larger document describing the Science Operation Department as a whole.


This document is the result of the discussion that took place on Thu. 2002 Mar. 18 at la Silla and Vitacura. Were present at that meeting, in Vitacura, Emmanuella Pompei, John Pritchard, Leonardo Vanzi, Malvina Billeres, Michael Sterzik, Rene Mendez, and in La Silla, Lisa Germany, Martin Kurster and Olivier Hainaut. Gaspare Lo Curto had sent some written input. Version 0.2 was released to the LaSilla audience for discussion and comments. These comments were edited by R.Mendez.  Contributions are from G. Hau, L. Vanzi, K.Brooks  and R. Mendez. Additional comments were received from J. Melnick, D. Alloin  and J. Breysacher. Comments and discussion are included in v.0.9 of this document.


In this document, "he" and "his" refer to the position described. In practice, these positions can be occupied by people of any gender.



DMD Data Management (and Operation) Division
MPE Max Planck Institute
MTS Medium Term Scheduling
OB Observation Block
OPC Observation Program Committee
OpA Operation Astronomer, aka 80/20 Astronomer
P2PP Phase II Preparation Package
QC Quality Control
QC Quality Control
SM Service Mode
USG User's Support Group
VA Visiting Astronomer
VM Visitor Mode
VisAs Visiting Astronomers Department
WFI Wide Field Imager



In this section, Astronomer refer to all the flavors of astronomers available, i.e. Staff, OpAs, Fellows (described in [1]) and to a certain extent, Students.

The tasks and duties of the La Silla SciOp Astronomers are


It is considered desirable that, in the case of VM, the Phase II (P2PP, strategy, etc) and the night support are provided by the same person, i.e. as done at present. It is considered desirable that, in the case of VM, the Phase II (P2PP, strategy, etc) and the night support are provided by the same person, i.e. as done at present, in order to have continuity and to optimize the communication level. However, it should be noted that some of the Telescope Introduction could possibly be delegated to the TIO (e.g. tour of the telescope). This has to be experimented with.

The Phase II preparation could take place in Vitacura, e.g. in cases where that would permit the support astronomer to come later on the mountain. This was experimented with success at the NTT. It should however remain an exception, the normal mode of operation being Phase II intro at La Silla. Indeed, the astronomer's time at Vitacura is for Science, but it is better to "lose" 2h of science for an introduction than to "lose" 2 days. The hardware and software set-up in Vitacura will need to be improved (i.e. have a "Visitor Computer" with P2PP and up-to-date instrument packages).

It is also stressed that the VAs should do their homeworks before the Phase II preparation, i.e. read the manuals and think about what they want to do. This will have to be made clear to the VAs before they arrive.

Even "experienced" observer will have to go through all the point of the standard introduction. The support astronomer can of course go over some of these points very quickly if the VA is very familiar with them, but the support astronomer has to make sure that nothing is forgotten!

The possibility of (limited) "remote observing" or "remote operation" from Vitacura is also considered. This would permit more flexibility, e.g. in case of trouble-shooting, tests, and even observations. This is to be experimented with.


Obviously, what follows concerns the astronomers after the completion of their training period.


Every astronomer (staff and OpA) should belong to one Instrument Force (cf [2]), and be able to support all instruments in that force (to the level of a good generic introduction), and be specialist (i.e. be able to provide in-depth support and good level of trouble-shooting) of at least one instrument. After some time at La Silla, the Astronomers should also be able to provide basic support on at least one instrument of another Instrument Force.

Most astronomers are likely to be at some point Instrument Scientist (cf [2]) of an instrument.

As stated in [1], it is expected from the Astronomers that they will remain informed while being in Vitacura, by reading emails and replying to urgent emails related to their duties, and perform/complete urgent tasks related to their duties for SciOp. This should take a very small fraction of their research time.

ESO considers that a "support astronomer" should be an "active astronomer". This is the justification of the 20% of the 80/20. Nevertheless, ESO acknowledge that it hard/difficult/impossible to be a world-wide top scientist with only 20% of one's time to do research. As a consequence, the performance appraisal of the OpAs is based only on their functional work, not on their science (as opposed to the 50/50 astronomers). On a case by case bases, OpAs could request to be passed on a 100/0 scheme (i.e. 150n duties, no science).

2.3.2- FELLOWS

Every Fellow should be specialist (to the level of providing in-depth introduction and basic trouble-shooting) of one instrument, and be able to provide generic introduction on at least  another instrument of the same instrument Force.

Most fellows are likely to be at some point Instrument Scientist (cf [2]) of an instrument. Indeed, as La Silla will have 10 instruments and 12 astronomers (inc. Fellows), their role will be crutial.

The contract of the Fellows include 80n of duties on the mountain, and 35 days of duties in Vitacura. These 35d are used to ensure the continuity of their service to SciOp (e.g. read SciOp email, reply to those concerning them directly, complete urgent tasks, etc.), and perform background tasks such as documentation, analysis, etc. The Fellows are not expected to keep detailed track of their time in Vitacura, but experience (+ time record from some template fellows) shows that this does not amount to 35d. The remainder is considered as a compensation for possible over-run of their 80n quota on La Silla (not to be abused, and to be kept at a small level, e.g. no more than 10%), required by emergency situations or schedule impossibilities.


Currently, the ESO Students are not included in the La Silla Operation, although some experienced was gained from Students who volunteered to work for the Teams. Students have no obligation (by contract) to perform duties at the Observatories. It must be noted that the most important goal of the Observatory is to support the observing projects, not train students. It is therefore important that the Observatory should get some return from the resources invested in the students.

The current experience with students showed that involving them in long term projects is a failure: they don't come enough to La Silla, and they are not supposed to work in such project in Vitacura. On the other hand, they proved to provide very efficient help for very well defined tasks that can be completed in very short time (few hours to few days, to be competed before they finish their "turno"), i.e. "here-and-now" projects.

Based on this, it is proposed that the Students will be proposed to volunteer to perform a small amount of duties (of the order of 40n/yr). These duties will be of the "here-and-now" kind, i.e. should be completed at the end of their "turno". These will be decided on a trimester by trimester bases (i.e. each scheduling period). Once accepted (i.e. once the schedule is accepted and published), the Student are committed to perform the scheduled "turnos" and to follow the instructions they are given.

The implementation of this scheme will be negotiated with the relevant instances (Science Division, etc), and the budget to cover their travel and stay expenses will have to be secured for >2002. For 2002, an arrangement has been found between the different parties: Science/Vitacura pais the trips, SciOp pais the stay.



This section is a summary, for information purposes, of the relevant sections of the SciOp Staffing Plan [3].
Currently, the staff of SciOps includes 5 Staff Astronomers (>=105n/yr), 4 OpAs (>=120n/yr, with some variation from contract to contract) and 7 Fellows (=80n/yr). In the long run (>=2004), SciOp will have 4 Staffs, 3 OpAs and 3 Fellows (assuming one of the remaining Fellow position is converted in an OpA, which is the current plan).

This will ensure 980 man-night/yr, i.e. an average of 2.7 astronomer per night. It is therefore not possible to ensure full coverage of 1 astronomer/night/telescope.

In that framework, the Common Control Center will play an important role: one astronomer will be able to support more than one telescope, provided that

The Common Control Center will therefore have to be implemented asap.


Currently, the OpAs have 1-yr "Paid Associate" contracts with no retirement benefits, with a duty level varying between 120 and 135 nights/yr.

The duty level should be uniformized for all new contracts, e.g to 125n/yr, which is the number currently used for scheduling purposes. Also, the OpA contracts should be as much as possible made similar to those of Paranal, i.e. 3yrs with retirement benefits. The implementation of this point will have to be negotiated with the relevant instances (Pers. and Co).


In order to ensure the quality of the support, it will become a necessity to constrain the program schedule as follow

The implementation will have to be negotiated with the relavant instances.


The following is considered as what SciOp can reasonably and efficiently support in terms of Service Observations. Its implementation for P>=70 will be negotiated with the relevant instances  (OPC, VisAs and Co).


Visitor Mode: a Visiting Astronomer to perform his own observations on defined nights.

Flexible Observing: aka "queued observing", aka Q-mode: during some pre-defined nights, observations are selected for execution from a pool of pre-prepared OBs according to the weather conditions, instrument availability, priorities, etc.

Delegated Observing: on pre-defined nights, a specific observing program is executed by SciOp staff. From the scheduling point of view, this is similar to VM.


4.2.1- 3.6m

Currently, ~3-5% of the time is performed in Service Mode, exclusively as Delegated Observing. As the 3.6m does not receive support from DMD/USG for Phase II, QC and data distribution, this should remain at the ~5% level. As there is no instrument flexibility, and as the number of night in SM is very small, Flexible Scheduling is not an option, so the SM should be exclusively performed as Delegated Observing, and strictly be reserved to

In particular, programs of >= 2 nights should not be accepted in Service Mode any more, since there is no justification for this to happen. More specifically, the justification that "an observer from the proposal is not absolutely needed at the telescope" should not be sufficient to grant Service Mode.

4.2.2- NTT

A small fraction of the time, about 5-10%, is performed in Service Mode. Thanks to the fact that, in general, all 3 NTT instruments are available at all times, this SM can be offered in full Q-Mode. Nevertheless, it should be strictly reserved to

The latter two will constitute the "filler" needed for when conditions are not exceptional (i.e. the majority of the time).

Programs of >= 2 nights with no specific constraints should not be accepted in Service Mode any more. More specifically, the justification that "an observer from the proposal is not absolutely needed at the telescope" should not be sufficient to grant Service Mode.

It must be noted that NTT receives no support from DMD for Phase II, MTS, QC, and data distribution. This is fine provided that the fraction of SM time remains <10%.

4.2.3- 2.2m

Three months per yrs (i.e. 25%) belong MPE, 75% to ESO. MPE can use both WFI and FEROS, and agreement with MPE is that 100% of its WFI time in SM. It is expected that about 1/3 of the ESO time will be scheduled with FEROS.