Predictions of stellar occultations by the main planetary satellites
Short Name:
voccdb.epn_core
Date:
19 Apr 2024 14:16:01
Publisher:
Paris Astronomical Data Centre
Description:
The VOccDB database provides prediction and parameters of stellar
occultations by the main planetary satellites. Observations of a
stellar occultations help to better determine the size and the shape
of the occulting body, as well as its astrometric position at the
milli-arcsecond level precision. Only the main moons of giant planets
Jupiter, Saturn, Uranus and Neptune are considered in the event
prediction database. Predictions are provided over period 2023-2032,
up to visual magnitude 12 for the biggest satellites, and magnitude 14
for other satellites. For each stellar occultation event prediction,
the database provides circumstances and observational data, date and
timing of the occultation, star position and magnitude, excepted
duration, etc.
"The growth of the Tharsis volcanic complex on Mars during
Noachian/Hesperian era induced a reorientation of the spin axis of the
planet (true polar wander). This service gives access to a map of Mars
topography before Tharsis formation (Early Noachian) and a map of Mars
topography before true polar wander (Late Noachian/Early Esperian),
from the model described in Bouley, S., Baratoux, D., Matsuyama, I. et
al. Late Tharsis formation and implications for early Mars. Nature
531, 344â347 (2016). https://doi.org/10.1038/nature17171 ."
The database contains profiles of atmospheric CO2 density and
temperature derived thereof, and ozone concentration profiles, all
derived from the first year(s) of SPICAM UV stellar occultation
observations (Forget et al. 2009, Lebonnois et al. 2006). The database
also includes the full dataset of four Martian years of aerosol
extinction profiles from SPICAM UV solar occultations (Määttänen et
al. 2013).
Since 1973, the 18-cm lines of the OH radical have been
systematically observed in a number of comets with the Nançay radio
telescope. This allowed an evaluation of the cometary water production
rates and their evolution with time, as well as a study of several
physical processes: the excitation mechanisms of the OH radio lines,
the expansion of the cometary atmospheres, their anisotropy in
relation with non-gravitational forces, the Zeeman effect in relation
with the cometary magnetic field. The Nançay observations of 53
cometary apparitions between 1982 and 2009 are now organized in this
database.
*** USET sunspot drawing *** The Uccle Solar Equatorial Table (USET)
facility at the Royal Observatory of Belgium has gathered an
uninterrupted series of sunspot drawings since year 1941. This
collection continues to be updated when weather permits. This table
provides information about these drawings.
*** USET Groups *** Values in the USET sunspot group catalog are
derived from the solar drawings obtained by the Uccle Solar Equatorial
Table (USET) facility that is located at the Royal Observatory of
Belgium. The USET sunspot group catalog covers 82 years of
observations in 2021, and is updated every day. A home-made software
(DigiSun) written in Python is used to derive quantities such as
location and areas from the sunspot drawings.