What is the spectral type and luminosity class of the sun?

Since our Sun is a star, we can classify it according to its spectral and luminosity classes. The Sun is an example of a main sequence star, of spectroscopic type G2. Therefore, the combined color and luminosity class for the Sun is G2V (the same as alpha Centauri).

What luminosity class is the Sun in?

G2 V

The full classification for our Sun is G2 V. The G2 spectral type means it is yellow-white in color and the luminosity class V means it a hydrogen-burning, main-sequence star.

What kind of spectral class is the Sun?

class G star

The Sun is a class G star; these are yellow, with surface temperatures of 5,000–6,000 K. Class K stars are yellow to orange, at about 3,500–5,000 K, and M stars are red, at about 3,000 K, with titanium oxide prominent in their spectra.

What spectral and luminosity type is assigned to the Sun?

Ionized metals provide the most conspicuous lines in stars with temperatures from 6000 to 7500 K (spectral type F). In the coolest M stars (below 3500 K), absorption bands of titanium oxide and other molecules are very strong. By the way, the spectral class assigned to the Sun is G2.

What is the luminosity class?

A classification of stars according to their luminosity, which can vary widely for a given spectral type. Luminosity class indicates, for example, whether a star is a supergiant, a giant, or a dwarf.

What is the spectral class and luminosity class of red giant stars?

Red supergiants (RSGs) are stars with a supergiant luminosity class (Yerkes class I) of spectral type K or M. They are the largest stars in the universe in terms of volume, although they are not the most massive or luminous.
Properties.

What is luminosity of star?

Astronomers also measure luminosity — the amount of energy (light) that a star emits from its surface. Measuring star brightness is an ancient idea, but today astronomers use more precise tools to obtain the calculation.

How do you find the luminosity of the sun?

How do we determine the luminosity of the Sun? Another way to look at this is to measure the amount of energy in sunlight falling on a unit surface area, then multiply by the number of unit areas on the surface of a sphere with a radius of 1 `AU’.

What is luminosity physics?

Luminosity is an absolute measure of radiant power; that is, its value is independent of an observer’s distance from an object. Astronomers usually refer to the luminosity of an object in terms of solar luminosities, with one solar luminosity being equal to the luminosity of the Sun.

Does luminosity determine the classification of stars?

The most widely used system of star classification divides stars of a given spectral class into six categories called luminosity classes. These luminosity classes are denoted by Roman numbers as follows: Ia: Brightest supergiants. Ib: Less luminous supergiants.

Do stars of the same spectral type have the same luminosity?

Main sequence stars are luminosity class “V” whereas giant stars are luminosity class “II”. In this instance, the two stars have the same temperatures because they are in the same spectral class, but a luminosity class II star is larger and has a greater luminosity than a much smaller main sequence star.

What spectral class is the Sun quizlet?

So, for example, our Sun is a G2 V, where G2 is the spectral class (indicating that the Sun is a yellow-white star) and V is the luminosity class (telling us that the Sun is a main-sequence star).

How are stars classified by spectral type?

Stars are classified by their spectra (the elements that they absorb) and their temperature. There are seven main types of stars. In order of decreasing temperature, O, B, A, F, G, K, and M. O and B stars are uncommon but very bright; M stars are common but dim..

What two factors determine luminosity?

If they know the star’s brightness and the distance to the star, they can calculate the star’s luminosity: [luminosity = brightness x 12.57 x (distance)²]. Luminosity is also related to a star’s size. The larger a star is, the more energy it puts out and the more luminous it is.

What are the 7 spectral classes of stars?

The stars are divided into 7 classes designated by the letters O, B, A, F, G, K, and M; the hottest stars (O and B) are blue-white in color, while the coolest (M) are red.

What are the spectral type temperature and luminosity of star A?

The star A is of spectral type B, having temperature in the range of 17000 K −18000 K . The star A has absolute magnitude of 0 to (−1) and luminosity of star A is 100 solar units.