Preparing for Observations at Paranal Night Falls at Paranal —
Preparing for the Observations KUEYEN is tilted towards the
horizontal position during a test exposure sequence. (Photo
obtained on March 23, 2000). Astronomical observations begin
soon after sunset at Paranal. Normally, they start with a series
of test and calibration exposures that serve to determine the
exact status of the various instruments, e.g., in terms of
sensitivity at different wavelengths. Some of these exposures
are performed on a white target on the inside of the telescope
enclosure, others are made on the sky, as it gets progressively
darker. If they are included in a programme, observations of
comparatively bright objects may be carried out while the sky is
still relatively bright. However, those of the faintest objects
must wait until the period of "astronomical twilight" is over,
i.e., when the Sun is at least 18° below the horizon. About the
Image |Release date:||16 June 2000| |Size:||7370 x 8856 px|
About the Object |Name:||Ver