Specifications

102 AUTOSTAR CCD PHOTOMETRY
Eruptive Variables
The eruptive variables tend to produce sudden, unpredictable
outbursts of energy. Examples are Flare stars (Cataclysmic
Variables), Novae, and Supernova types. Amateurs have done
yeoman duty in coordinating ground-based observations with
professionals, as sort of an “early warning” network to help
schedule space satellite observatories.
Extrinsic Variables
These stars exhibit light variations caused by external reasons, e.g.,
such as another object (a star, an extrasolar planet, or a
protoplanetary disk) passing in front of them. These are typically
noted as eclipsing binaries. But while they may be studied as
eclipsing binary stars, the systems may actually contain more
than two stars and may also have intrinsic and eruptive variables
within the system. Using standard UBVRI photometric filters,
additional information can be obtained. HPO is monitoring
Epsilon Aurigae, an interesting eclipsing star with a very long
(27.1 years) period.
Nova and Supernova Photometry
While photometric studies of Novae (in our own galaxy) and
Supernovae (SNe) are certainly important, it is rare that amateurs
have the opportunity to follow them. Faint SNe occur frequently in
other galaxies, but detecting them is usually beyond the means of
most amateurs. Photometry of active Seyfert galaxies may be
within the limits of amateur equipment.
Asteroid Photometry
Asteroid photometry is challenging, as they are usually fast
moving and relatively faint, but white light curves can be acquired
without specialized filters. Asteroid light curves are of strong
interest, as rotation rates, sizes, and surface colors (compositions)
can be investigated. The light curves also aid in modeling radar
observations to map the shapes. Amateurs can perform important
work by quickly responding with observations of fast-moving
Earth-crossing objects. Information can be obtained to confirm the
size and trajectory of potentially hazardous asteroids. Some of
these are being confirmed as binary objects, some with satellites.