LIDAR
Light detection and ranging
LRGB
Luminance, red, green, blue: A colour image with a luminance frame
LST
Local Sidereal Time: The current time at an observer’s location based
on the transit of astronomical objects across the local meridian
MOS
Multi-object spectrography. A device for taking many spectra at once
Mpc
Megaparsec: 1 million parsecs
MPC
Minor Planet Center: The IAU body responsible for solar system
objects. The MPC holds an extensive database of comets and asteroids
NDF
Neutral density filter: A filter that reduces brightness without affecting
the spectral ratio of the source
NGC
New General Catalogue of Nebulae and Clusters of Stars: A large
astronomical catalogue of nonstellar sources
NOFS
Naval Observatory Flagstaff Station: A large observatory located in
Arizona
NOMAD Naval Observatory Merged Astrometric Dataset: A large astronomical
catalogue produced by, amongst others, the NOFS
pc
Parsec: A unit of astronomical distance equating to approximately
3 Â 10
16 m. The parsec is the distance of an object that would have a 1
arc second parallax
PNe
Planetary nebula: A type of nebula-related formation of a white dwarf
PSF
Point spread function: In photometry, the function that describes how
the light from an object spreads over the frame. It is most often a
Gaussian
QE
Quantum efficiency: The efficiency of a quantum device, for example,
a CCD
RA
Right ascension: The horizontal location of an object on the celestial
sphere
RBI
Residual bulk image: The appearance of a false star in an image caused
by the saturation of a CCD
RGB
Red, green, blue: A colour image
RMS
Root mean square: The square root of the mean of the squares of the
sample
SIMBAD Set of Identifications, Measurements, and Bibliography for
Astronomical Data: an online searchable database of astronomical
objects
SNR
Signal-to-noise ratio: The ratio of the signal to the noise of the system.
A general indication of uncertainty
STScI
Space Telescope Science Institute: The organisation that manages the
day-to-day operation of the Hubble Space Telescope
UGC
Uppsala General Catalogue: A northern hemisphere catalogue of
galaxies
Acronyms
xvii
Light detection and ranging
LRGB
Luminance, red, green, blue: A colour image with a luminance frame
LST
Local Sidereal Time: The current time at an observer’s location based
on the transit of astronomical objects across the local meridian
MOS
Multi-object spectrography. A device for taking many spectra at once
Mpc
Megaparsec: 1 million parsecs
MPC
Minor Planet Center: The IAU body responsible for solar system
objects. The MPC holds an extensive database of comets and asteroids
NDF
Neutral density filter: A filter that reduces brightness without affecting
the spectral ratio of the source
NGC
New General Catalogue of Nebulae and Clusters of Stars: A large
astronomical catalogue of nonstellar sources
NOFS
Naval Observatory Flagstaff Station: A large observatory located in
Arizona
NOMAD Naval Observatory Merged Astrometric Dataset: A large astronomical
catalogue produced by, amongst others, the NOFS
pc
Parsec: A unit of astronomical distance equating to approximately
3 Â 10
16 m. The parsec is the distance of an object that would have a 1
arc second parallax
PNe
Planetary nebula: A type of nebula-related formation of a white dwarf
PSF
Point spread function: In photometry, the function that describes how
the light from an object spreads over the frame. It is most often a
Gaussian
QE
Quantum efficiency: The efficiency of a quantum device, for example,
a CCD
RA
Right ascension: The horizontal location of an object on the celestial
sphere
RBI
Residual bulk image: The appearance of a false star in an image caused
by the saturation of a CCD
RGB
Red, green, blue: A colour image
RMS
Root mean square: The square root of the mean of the squares of the
sample
SIMBAD Set of Identifications, Measurements, and Bibliography for
Astronomical Data: an online searchable database of astronomical
objects
SNR
Signal-to-noise ratio: The ratio of the signal to the noise of the system.
A general indication of uncertainty
STScI
Space Telescope Science Institute: The organisation that manages the
day-to-day operation of the Hubble Space Telescope
UGC
Uppsala General Catalogue: A northern hemisphere catalogue of
galaxies
Acronyms
xvii