Instrument Availability and Target Accessibility: 2005A

The tables below indicate the current best estimates of instrument availability and corresponding target (RA, dec) accessibility for 2005A. Typically several observations or programs are rejected at the ITAC each semester because of target accessibility so please read carefully the following notes:

For each given declination, the table shows the target RA that has two hours above airmass = 2 at the start of the night early in the semester ("minimum" RA) and the target RA that has two hours above airmass = 2 at the end of the night late in the semester ("maximum" RA).

For some high and low declinations (noted *), an airmass limit of 2.5 is used.
If best image quality is desired, typically achieved at smaller zenith distance, the RA range should be reduced appropriately.

The comments column indicates whether all RAs are potentially observable.

"no restriction" means that all RAs are potentially observable.
"restricted" means that only RAs between the "minimum" and "maximum" can be accepted for observation in this semester. Targets with RA less than the "minimum" will set too early in the night and cannot be observed; targets with RA greater than the "maximum" will rise too late in the night and cannot be observed.

At the extrema of the RA range, shown by the early- and late-semester values, targets may not be observable in practice due to detailed instrument and engineering schedules and other constraining factors (e.g. lunar phase). Moreover, the time for which the target (RA, dec) is accessible may be very limited and applicants should bear this in mind for faint targets. The likelihood of execution is greatly increased if extreme RAs are avoided.
In some cases, an instrument or instrument mode is foreseen to be available for only part of the semester. Such instances are listed after the main table.

Gemini North

Instrument(s)	declination (deg)	RA range (hh mm)
Instrument(s)	declination (deg)	Comments	"minimum" RA (early semester)	"maximum" RA (late semester)
NIRI (including Altair) GMOS North Michelle	80 *	no restriction	2h 10m	2h 40m
	70	restricted	2h 40m	2h 10m
	60	no restriction	2h 10m	2h 40m
	50	no restriction	2h 00m	2h 50m
	40	no restriction	2h 00m	3h 00m
	30	no restriction	2h 00m	2h 50m
	20	no restriction	2h 10m	2h 50m
	10	no restriction	2h 20m	2h 30m
	0	restricted	2h 35m	2h 20m
	-10	restricted	2h 55m	2h 00m
	-20	restricted	3h 25m	1h 30m
	-30	restricted	4h 05m	0h 50m
	-40 *	restricted	4h 25m	0h 30m
HIRES (on Keck)	all	restricted	Available for 2 nights in March and 3 nights in June (Precise dates TBD)

Gemini South

Instrument(s)	declination (deg)	RA range (hh mm)
Instrument(s)	declination (deg)	Comments	"minimum" RA (early semester)	"maximum" RA (late semester)
GMOS South T-ReCS Phoenix Acquisition Camera	30 *	restricted	5h 35m	1h 40m
	20	restricted	5h 15m	2h 00m
	10	restricted	4h 25m	2h 50m
	0	restricted	3h 55m	3h 20m
	-10	no restriction	3h 30m	3h 45m
	-20	no restriction	3h 10m	4h 05m
	-30	no restriction	2h 55m	4h 25m
	-40	no restriction	2h 40m	4h 35m
	-50	no restriction	2h 25m	4h 50m
	-60	no restriction	2h 15m	5h 05m
	-70	no restriction	2h 00m	5h 15m
	-80	no restriction	1h 55m	5h 20m
GNIRS (only available until end April)	30 *	restricted	5h 35m	19h 20m
	20	restricted	5h 15m	19h 40m
	10	restricted	4h 25m	20h 30m
	0	restricted	3h 55m	21h 00m
	-10	restricted	3h 30m	21h 25m
	-20	restricted	3h 10m	21h 45m
	-30	restricted	2h 55m	22h 05m
	-40	restricted	2h 40m	22h 15m
	-50	restricted	2h 25m	22h 30m
	-60	restricted	2h 15m	22h 45m
	-70	restricted	2h 00m	22h 55m
	-80	restricted	1h 55m	23h 00m

Last update August 25, 2004; Phil Puxley