Found 4 talks width keyword photometers

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Friday November 6, 2020
IAC

Abstract

An original method for measuring the atmospheric turbulence is described, capable of even measuring the tip-tilt, which normally requires a dedicated natural star and nowadays defines the practical limit of the adaptive optics technique. The method is based in the illumination of a wide area of the Sodium Layer, and to use their inhomogeneities as a reference. Sevaral analysis and simulation results will be presented.

Zoom link:
https://rediris.zoom.us/j/87053930312

Enlace youtube: https://youtu.be/c1TCdt_-S_o


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Thursday February 21, 2019
Severo Ochoa senior researcher

Abstract

TBD


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Tuesday February 19, 2019
Deutsches SOFIA Institut, Univ. of Stuttgart, Germany (retired)

Abstract

 

SOFIA, short for Stratospheric Observatory for Infrared Astronomy,
is a 2.7m telescope flying on a Boeing 747SP at altitudes of 12-14km,
to detect and study mid- and far-infrared radiation that is blocked
by water vapor in the earth's atmosphere and cannot reach the
ground. It is the successor to the Kuiper Airborne Observatory (1974-1995)
and currently the only access to and platform for astronomical observations
in the far-infrared (30-300 microns), except for balloon-borne telescopes.
 
SOFIA normally flies out of California, but once a year also
deploys to the Southern Hemisphere (usually to Christchurch,
New Zealand), benefitting from the excellent wintertime
stratospheric conditions to study the rich southern skies.
Although a bilateral project (80:20)
between USA (NASA/USRA) and Germany (DLR/DSI), it is open for
proposals from the world-wide astronomical community at large.
It addresses many science questions that ESA's successful but
now extinct Herschel Observatory has left unanswered and
offers observational opportunities similar to and beyond Herschel.
SOFIA also has many synergies with ALMA and APEX, as well as IRAM
and other submm and radio telescopes.

In part I of this SOFIA lecture, I will introduce the observatory 
in general, the plane, the telescope, the mode of operation, and 
in particular the current and future instrumentation.

In part II (later this week),  I will present a glimpse of SOFIA science
highlights and discoveries in its first 6 years of operation
(since 2012), including the most recent astrophysical and astrochemical 
results. I will also address its future ISM and star formation potential.  

SOFIA is a unique observatory, different from ground-based and
space platforms, which will serve the mid- and far-infrared 
astronomical community for many years to come.
 
It is a fascinating experience to fly on SOFIA! 


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Thursday April 8, 2010
Université de Sherbrooke, Canada

Abstract

Measuring the Aerosol Optical Depth (AOD) is of particular importance in monitoring aerosol contributions to global radiative forcing and air quality. Most measuring methods are based on direct or indirect observation of sunlight and thus are only available for use during daylight hours. Attempts have been made to measure AOD behavior at night from star photometry, and more recently moon photometry. Star photometry method uses spectrally calibrated stars as reference targets this provides somewhat more flexibility than a sun photometer but there are low-signal and calibration issues which can make these measurements problematic. Moon photometry is only possible when the moon is present in the sky. We suggest a complementary method, based on the observation of artificial sky glow generated by light pollution. The methodology requires (1) the implementation of an heterogeneous 3D light pollution model and (2) the design of an automated light pollution spectrometer which will be presented here. The instrument designated as the Spectrometer for Aerosol Night Detection (SAND) is now in its third version. Basically, SAND-3 is an automated CCD based, long-slit spectrometer protected from inclement weather by an acrylic dome. SAND have been used successfully in many astronomical sites along with some urban sites. Our first day/night (continuity) AOD measurements comparisons with AERONET/AEROCAN sunphotometer data will be shown for Sherbrooke university (Quebec, Canada) atmospheric optical observatory.

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