Cepheid variable Star whose luminosity varies in a characteristic way, with a rapid rise in brightness followed by a slower decline.
The glimmer that galvanized the PLANET and GMAN teams began with a sharp spike around 19 June, followed by a slow rise in brightness and--by some accounts--a strange, double-humped peak around 24 July before a final dimming.
By precisely measuring the drop in brightness of a star as it is occulted by the Moon (or the rise in brightness when it reappears), the star's angular diameter can be computed.
But other comets have very discontinuous light curves that make them totally unpredictable, such as comet C/1989 X1 (Austin), which first rose steeply in brightness and then leveled off to finish several magnitudes fainter than expected; and numerous comets such as the recent C/1999 S4 (LINEAR) break apart and fade from view (as C/1999 S4 did in July and August 2000).
Though observations of other FELTs are needed to confirm this conclusion, the unusually rapid rise and fall in brightness appears to be a signature of stars that belch out shells of matter in mini-eruptions before exploding entirely.
By comparison, C/1995 O1 (Hale-Bopp) has evidently made numerous trips through the inner solar system, every few thousand years, and there was reason to think that it would rise more rapidly in brightness than did Kohoutek.
Khatami tried several scenarios to explain the rise and fall in brightness, such as the explosion of a white dwarf star, or a binary merger followed by a supernova, but none could reproduce the observations except the collision of ejecta with an envelope of gas shed earlier by the star.
As the black holes and their attendant disks swing around each other at high speeds, the light from the disk that is coming toward us receives a boost from relativistic effects — a so-called Doppler boost — the way a siren grows louder and more high-pitched as it approaches, giving rise to a periodic increase in brightness every five years.
But Glasgow wants to go further and has programmed them to increase in brightness if noise levels rise - for example if there is a disturbance in the area.
"Their innards and entrails gushed to the desert floor, and as those around them turned to run, they too were slain, their blood pooling and rising in the unforgiving brightness of God".
The type V class was coined for SN 1961V in NGC 1058, an unusual faint supernova or supernova imposter with a slow rise to brightness, a maximum lasting many months, and an unusual emission spectrum.
