The deadline for the submission of proposals for Spanish CAT night observing time for semester 2017A is Tuesday, 4 October 2016, at 17 h Canarian local time. The call for collaborative proposals between Spanish and Mexican astronomers at the GTC (Spanish/Mex Time, see below) is also open, with the same deadline.

We recall that every proposal within the Spanish CAT scheme must be led by a principal  investigator (PI) affiliated to a Spanish Institution. GTC Spanish/Mex proposals can have either a Spanish or Mexican PI, and must include co-Investigators (co-Is) from both communities (see below).
The start and end of the semester change with telescope as illustrated next:
WHT, INT, Mercator, Stella:   February – July.
NOT, TNG:   April – September.
GTC:   March – August.
Liverpool (LT):   January – August (a two-month overlap period is adopted at the start and end of each semester, when proposals from both semesters may be observed in order to reduce problems with under-filled observations queues).
Large programs are not accepted for GTC in semester 2017A. Large program proposals extending over two semesters (2017A and 2017B) are accepted for WHT and INT (see below for details). Large program proposals extending up to four semesters (2017A through 2018B) with TNG, NOT, LT, Mercator, and/or Stella can be submitted. See below.
Please, read carefully the following information and recommendations made for each telescope and for large programs. There are changes with respect to previous calls for proposals.