Horizon Limits

The CTIO 4m telescope, also known as Blanco telescope, has an equatorial mounting. Due to this the telescope cannot point everywhere. 

The next figure shows the area of the sky visible to Blanco telescope (grey area) and the area of the sky that can not be observed (red grid).

The Blanco operational range is delimited by the following values of hour angle (HA) and declination (Dec):

HA [hh:mm:ss] Dec [deg]  
   00:00:00 37
+/-01:06:00 35
+/-02:03:36 30
+/-02:38:24 25
+/-03:04:48 20
+/-03:25:48 15
+/-03:43:12 10
+/-03:58:48 5
+/-04:12:36 0
+/-04:25:12 -5
+/-04:36:36 -10
+/-04:47:24 -15
+/-04:57:36 -20
+/-05:07:12 -25
+/-05:15:00 -30
+/-05:15:00 -35
+/-05:15:00 -40
+/-05:15:00 -45
+/-05:15:00 -50
+/-05:15:00 -55
+/-05:15:00 -60
+/-05:15:00 -65
+/-05:15:00 -70
+/-05:15:00 -75
+/-05:15:00 -80
+/-05:15:00 -85
+/-05:15:00 -89

However, it is recommended not to point to:

  • Dec=-88d59m59s 

or

  • Dec=+38d59m59s 

due to the risk of the mount crossing -89d or +39d (respectively) while tracking due to small perturbations.

Detailed information may be found here.