Information for Observers

  • GEOGRAPHIC COORDINATES:

    The geographic coordinates at the base of the "Jorge Sahade" telescope are: 4h37m12s West Longitude (W 69o18' 12" ); -31o47' 57" Latitude; altitude above sea level 2552 m.

    The geographic coordinates at the base of the "Helen Sawyer Hogg" telescope are: 4h37m13.5s West Longitude (W 69° 18' 23.16''); -31°47' 14.46" Latitude; altitude above sea level 2591 m.

  • PHASES OF THE MOON:

    Click here to see the phases of the Moon for one year.

  • RISE, SET, CULMINATION AND TWILIGHT TIMES:

    This page of the U.S.N.O. provides information about sunrise/sunset, moonrise/moonset, twilight times, etc. for any location.

  • SKY MAP:

    Images of any part of the sky may be extracted from the Digital Sky Survey in either FITS or GIF format.

  • ON-LINA AEROSOLS DATA:

    In this page you have aerosols data at CASLEO provided by AERONET. Please search the list for CASLEO station.

  • ON-LINE WEATHER DATA:

    Metereological information from the station set up at Burek Mountain are available here.

  • ON-LINE ASH CLOUD DETECTOR:

    Click here to view data from the ASH Cloud Detector installed at Burek Mountain, as well as some other climate data also provided by such detector.

  • SATELLITE METEREOLOGICAL INFORMATION:

    Metereological satellite map on ESO webpage showing CASLEO’s location.

  • NIGHT SKY IMAGE:

    Night sky image from El Leoncito in real time.

  • NIGHT SKY BRIGHTNESS:

    It was measured by Clariá and Bica (1990, private communication), who obtained the following values:

    Bandmag/asec2
    U 22.1
    B 23.3
    V 22.7

    To see the values in real time for the night sky at El Leoncito click here.

  • MEAN EXTINCTION COEFFICIENTS:

    These coefficients were determined by Minniti, Clariá, and Gómez (1989, Astroph. and Space Science, 158, 9) for the UBVRI and DDO systems.

    Users can apply the method described by Massey and Davis ("A User's Guide to Stellar CCD Photometry with IRAF") to resolve transformation equations separately for each band (without using mean extinction coefficients).

    UBVRI

    Mag / color1st order2nd order
    U-B 0.20 +/- 0.02 0.01 +/- 0.01
    B-V 0.11 +/- 0.01 -0.02 +/- 0.01
    V-R 0.05 0.00
    R-I 0.04 0.00
    V 0.17 +/- 0.01 0.00 +/- 0.01


    Recently, the technical staff of CASLEO has obtained new mean extinction coefficients using the current filter set and the CCD Roper 1300B. The values obtained are:

    JUNE 2010:

    Mag / color1st order2nd order
    U-B 0.18 +/- 0.01 0.00
    B-V 0.12 +/- 0.01 -0.05 +/- 0.02
    V-R 0.05 +/- 0.01 0.00
    R-I 0.06 +/- 0.01 0.00
    V 0.14 +/- 0.01 0.00 +/- 0.01

    MARCH 2011:

    Mag / color1st order2nd order
    U-B 0.26 +/- 0.01 0.00
    B-V 0.11 +/- 0.01 -0.03 +/- 0.01
    V-R 0.04 +/- 0.01 0.00
    R-I 0.05 +/- 0.01 0.00
    V 0.13 +/- 0.01 0.00 +/- 0.01

    DECEMBER 2014 (see Fernández-Lajús et al. BAAA 58, 2016):

    Mag / color1st order2nd order
    U-B 0.34 +/- 0.03 -0.01 +/- 0.03
    B-V 0.19 +/- 0.02 -0.01 +/- 0.02
    V-R 0.01 +/- 0.02 -0.05 +/- 0.02
    R-I -0.01 +/- 0.03 0.10 +/- 0.03
    V 0.16 +/- 0.01 0.01 +/- 0.01

    JANUARY 2015:

    Mag / color1st order2nd order
    U-B 0.26 +/- 0.01 0.00
    B-V 0.12 +/- 0.01 0.00
    V-R 0.04 +/- 0.01 0.00
    R-I 0.02 +/- 0.01 0.00
    V 0.23 +/- 0.01 0.00

    DDO

    Mag / color1st order
    41-42 0.02 +/- 0.01
    42-45 0.05 +/- 0.02
    45-48 0.04 +/- 0.01
    48 0.21 +/- 0.01