Table of Contents
What is an asteroid light curve?
A light curve is the measurement of a celestial body’s brightness at certain intervals and over a given period of time (hours, days, months…).
What can be learned about an asteroid from its light curve?
A more direct reason why asteroid light curves are important is that in the end, it can help determine possible correlations between asteroids rotational period, size, taxonomic class, location in the asteroid belt and even more properties. It can also help determine the shapes and pole orientations of the asteroids.
What is the light curve analysis?
Light curves are graphs that show the brightness of an object over a period of time. In the study of objects which change their brightness over time, such as novae, supernovae, and variable stars, the light curve is a simple but valuable tool to a scientist.
What affects an asteroids brightness?
An asteroid’s apparent brightness depends on both its albedo and its diameter as well as on its distance.
What could you predict about a planet’s size by the depth of its transit?
What could you predict about a planet’s size by the depth of its transit? What predictions could you make about a planet’s distance from its star based on its transit duration? A large planet blocks more light than a small planet. The larger the planet, the greater the decrease in brightness, or transit depth.
Why do variable stars change in brightness?
There are two different categories of variable stars. Intrinsic variables are stars whose luminosity physically changes due to pulsations, eruptions or through swelling and shrinking. Extrinsic variables are stars that change in brightness because of being eclipsed by stellar rotation or by another star or planet.
What is a grid of photometers which simultaneously measure and record photons from celestial objects?
A CCD camera is essentially a grid of photometers, simultaneously measuring and recording the photons coming from all the sources in the field of view.
How do you plot a light curve?
To plot a light curve, determine the magnitudes of your novae on each data frame on which it can be seen. Then plot the brightness of the nova (in magnitudes) on the y-axis, versus time on the horizontal (X) axis.
What are the 3 different types of asteroids?
The three broad composition classes of asteroids are C-, S-, and M-types.
- The C-type (chondrite) asteroids are most common. They probably consist of clay and silicate rocks, and are dark in appearance.
- The S-types (“stony”) are made up of silicate materials and nickel-iron.
- The M-types are metallic (nickel-iron).
What are the two factors that will determine the impact of an asteroid?
A massive asteroid colliding with Earth, as depicted in an artist’s conception. The amount of damage caused by the impact of an object with Earth is determined primarily by two factors: the object’s mass and its relative velocity. These determine the total kinetic energy released.
How does NASA find planets light years away?
While we cannot yet send spacecraft to planets beyond our solar system, scientists can study the light from exoplanets with telescopes. The telescopes they use to observe this light can be either in space, like the Hubble Space Telescope, or from the ground, like the Gemini Observatory telescopes.
What do variable stars tell us?
Research on variable stars is important because it provides information about stellar properties, such as mass, radius, luminosity, temperature, internal and external structure, composition, and evolution. Some of this information would be difficult or impossible to obtain any other way.
What are two types of variable stars?
There are two basic types of variable stars: intrinsic variables, whose luminosity actually changes, and extrinsic variables, whose apparent changes in brightness are due to changes in the amount of their light that can reach Earth. A star could be an intrinsic variable because it periodically swells and shrinks.
What is the difference between photometry and spectrophotometry?
Photometry measures the total brightness as seen by the human eye, but spectrophotometry measures the intensity at each wavelength on the whole range of the electromagnetic spectrum for which the measurements are necessary.
What are the two different types of photometry?
There are two types of photometry – differential and absolute. In differential photometry, the object under study is observed along with one or more nearby comparison stars. The ADU count for both objects are then compared to find the difference, which is then used to derive the difference in brightness.
What is light curve analysis in astronomy?
Light Curve Analysis. A light curve is the measurement of a celestial body’s brightness at certain intervals and over a given period of time (hours, days, months…). Asteroids shine due to the Sun’s light reflecting off their surface, and their brightness might vary due to one or more of the following factors: The asteroid’s distance…
How does the orbit of an asteroid affect the light curve?
If the orbit of an asteroid is well known, the first two effects can be numerically calculated and their contributions removed from the measured light curve. We are then left with a light curve whose changes are due solely to the spinning of the asteroid.
Why are asteroids brighter than other planets?
Asteroids shine due to the Sun’s light reflecting off their surface, and their brightness might vary due to one or more of the following factors: The asteroid’s distance to us is changing (closer objects appear brighter).