Light curve
In astronomy, a light curve is a graph of light intensity as a function of time. The light is usually in a particular frequency interval or band.
Light Curves and What They Can Tell Us
A light curve is a graph which shows the brightness of an object over a period of time.
Light Curve :
A light curve is graph of the changes in brightness with time of a star, particularly of the variable type. The light curves of different kinds of variable stars differ in the degree of change in magnitude (i.e.
Definition: light curve: A graph showing how the radiation from an object varies over time.
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Modelling Binary Light Curves
Exercise 1: Binary Stars - investigate a spectroscopic binary system
Exercise 2: Eclipsing Binary Stars - simulate light curves for different eclipsing binary systems ...
light curve A plot of the variation in brightness of a star with time.
Light Curve
A plot of magnitude or intensity versus time for a variable star.
Light Cylinder ...
Light Curve
A graph of brightness versus time commonly used in analyzing variable stars and eclipsing binaries.
Light Gathering Power ...
Light Curve - A plot of the brightness of a body versus time
Light-Gathering Power - A number, proportional to the area of the principal lens or mirror of a telescope, ...
[edit] Light curves
The light curves of beta Lyrae variables are quite smooth: eclipses start and end so gradually that the exact moments are impossible to tell.
Light curves for the twelve Cepheid variables in M100 that have been observed with Hubble. The absolute magnitude, M, is determined from the period of the Cepheids. Adapted from Freedman et al. (1994).
Light Curve
A plot showing how the light output of a star (or other variable astronomical object) changes with time.
Light-Year ...
Light curve of a Cepheid from HIPPARCOS
Credit: ESTEC, ESA.
Light curve of an eclipsing binary system
Credit: Swinburne ...
light curve The variation in brightness of a star with time. [More Info] ...
Light Curve: A plot of the amount of light detected from an object (i.e. the apparent magnitude) as a function of time. Light curves provide evidence of eclipsing binaries, variable stars, and track the progress of nova and supernova explosions.
The light curve of QS Virginis as the white dwarf moves in front of the red dwarf. White dwarfs are typically only about the size of a planet like Earth.
The light curves for Type II supernovae are distinguished by the presence of hydrogen Balmer absorption lines in the spectra. These light curves have an average decay rate of 0.
This light curve of a
three-hour x-ray flare
was associated with a
0.2-stellar-radius high
magnetic loop anchored
on Star B (more).
Typical light curve of gravitational microlensing event (OGLE-2005-BLG-006) with its model fitted (red) ...
The B-band light curves of all SNIa look the same. There is an initial very rapid increase in luminosity, where the brightness of the supernova can change by up to 3 magnitudes in 15 days, that ends at maximum light.
A nova whose light curve shows a much more gradual development - i.e., rise time of several days, maximum of several weeks, slower decline, amplitude only about 10 mag. [H76]
Small Magellanic Cloud ...
Vocabulary
light curve eclipsing binary
Formulae
Eclipsing binary: diameter = speed × time of eclipse.
Size from luminosity: star's radius/Sun's radius = (Sun's temperature/star's temperature)2 Sqrt[star's luminosity/Sun's luminosity].
The light curves of the different types of supernovae are shown - note that the Type I supernovae are brighter. Also, the rate at which they brighten and fade away is different. This helps astronomers distinguish the two types.
The top graph shows the visual (V) light curve of Beta Doradus over two cycles, where "phase" is the relative period, which begins with maximum light at 0 and ends with maximum light at 1.
The structure of the BATSE light curves told us much about the physics of these events, and the distribution of gamma ray bursts nearly evenly on the sky strongly suggested a cosmological origin.
Evidence for this was seen in 1987, in the fading light curve of a bright supernova called SN1987A, which for a while was entirely powered by radioactive decay energy, beautifully confirming the theory of what happens during such an explosion.
Type I (population II) supernovae can be recognized (and divided into subgroups a,b, and maybe c) based on their spectra and light curves.
The class to which a variable star belongs is determined by a plot of its light curve, which is a graph of the star's apparent brightness versus time.
The most famous class is the Cepheid variables with the light curves similar to the ones above. Their periods, in the range of a few days to a few months, have a definite relation with the luminosities.
Light curves reveal that the tiny, and thus rapidly eclipsed, accretion spot at the stream-facing pole emits about half the total radiated energy of the system, most of the rest coming from the extended stream, ...
Rotation periods are deduced from periodic brightness variations in the light curves. The (reflectivity), , and radius of an asteroid may be determined by measuring the infrared and visible fluxes at .
An astronomer can record the changing brightness of a Cepheid variable and plot the brightness change over time to create a light curve for the star. The distance to the Cepheid variable is then obtained by measuring the period of the light curve.
Short-period fluctuations in brightness caused by the rotation of an irregularly shaped asteroid or a spherical spotted asteroid (i.e., one with albedo differences) produce a light curve—a graph of brightness versus time— ...
The map, which covers 85% of the planet's surface, confirms that Pluto has a dark equatorial belt and bright polar caps, as inferred from ground-based light curves obtained during the mutual eclipses that occurred between Pluto and its satellite ...
Some critics of big bang have suggested that recent reviews of the proper motion of many quasars has shown that extreme distances are not possible.[2] These reviews, critics contend, cast doubt on the utility of quasar light curves to verify or ...
The light curve of this GRB is the best-sampled to date with over 100 data points.
Laboratory measurements of cosmic-ray effects on the recovered meteorites led to a calculation of the "true mass," which was intermediate between the photometric mass and the dynamic mass. Finally, the light curve (the plot of brightness versus ...
As this virtually never happens, this quantity is calculated from the comet's light curve. Unfortunately, this quantity is far from absolute. It can be different pre- and post-perihelion.
 See also: Light, Time, Energy, Star, Period
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