Choose the correct statements concerning spectral classes of stars. (Give ALL correct answers, i.e., B, AC, BCD...) A) Neutral hydrogen lines dominate the spectrum for stars with temperatures around 10,000 K because a lot of the hydrogen is in the n=2 level.   B) Hydrogen lines are weak in type O-stars because most of it is completely ionized.   C) Oh Be A Fine Guy/Girl Kiss Me, is a mnemonic for remembering spectral classes.   D) The spectral sequence has recently been expanded to include L, T, and Y classes.   E) K-stars are dominated by lines from ionized helium because they are so hot.   F) The spectral types of stars arise primarily as a result of differences in temperature.

Q: Choose the correct statements from the following list referring to white dwarfs. (Give ALL correct…

A: Answer: A,B,D,E,F Summary: Star collapses inward on itself after running out of the fuel. White…

Q: Record the wavelength (in nm) in the data table. Calculate the frequency (in Hz, or 1/s) and the C…

A: Disclaimer: “Since you have asked posted a question with multiple sub-parts, we will solve the first…

Q: d²p GMp %3D dt2 (a² + p2)3/2* 2. Suppose that p < a, that is, the star is deep inside the cluster.…

A:

Q: The star 58 Eridani is a feint but naked-eye star similar to the Sun. Suppose that you are observing…

A: To calculate the number of photons per second that arrive at the retina, we need to know the star's…

Q: What are the approximate spectral type, temperature, absolute magnitude number, and luminosity of…

A: Required :  Spectral type, absolute magnitude, temperature and luminosity of star E.

Q: Find the speed for a star in which this line appears at wavelength 122.5 nmnm.

A: Given wavelength = 122.5 nm Hydrogen transition wavelength = 121.6 nm Speed of light is c = 3×108…

Q: (d) You now know the sum of the two masses, and their ratio as well: two equations for two…

A: Given,

Q: *IMPORTANT NOTE: DO NOT make any stars' masses or stage of life answer. reference as a reason to the…

A: Given that both stars have roughly the same surface temperature, and also considering the typical…

Q: Our Sun is considered an "average" star. What is the average star really like? Explain. Could you go…

A: We can define an average star as:  An average star, or more properly, an intermediate-mass star,…

Q: Suppose you observe a tight eclipsing binary with orbital period of 3 days, and radial velocity…

A: 1. Suppose you observe a tight eclipsing binary with orbital period of 3 days, and radial velocity…

Q: a) What is a binary star system? (b) describe briefly two methods for showing that a system is a…

A: (a) A binary star system is a system of two stars orbiting each other around a common center. Binary…

Q: You see two variable stars. One has a period of half a day and the other has a period of 100 days.…

A: There are two main types of variable stars – Cepheid and RR Lyrae. The Cepheid stars typically vary…

Q: A planetary nebula is visible due to ____.

A: The nebula is the bright area in the sky, which can be cloud of stars or gas.

Q: Consider two stars with temperatures of 10,000 and 25,000 Kelvin. 3. Calculate the ratio of atoms in…

A: Given: In this question, the given details are, Consider two stars with temperatures of 10,000 and…

Q: . Imagine a giant sphere with a radius of 1 AU surrounding the Sun. What is the surface area of this…

A: "Since you have posted a question with multiple sub-parts, we will solve the first three subparts…

Q: From its spectral type, the surface temperature of a main sequence star is measured to be about…

A: Using the 1r2 rule method, we can find out the star's distance by measuring the intrinsic brightness…

Q: Star A has a temperature of 5,000 K and Star B has temperature of 6,000 K. At what wavelengths (in…

A: Temperature of star A = 5000 k temperature of star B = 6000 k

Q: subject: astronomy) 1. When do you say a star is very hot compared to the red. 2. are stars of equal…

A: Answer (1) A blue star will always be hotter than the red star. It is independent of the relative…

Q: The total luminosity of the Sun is 4e26 Watts. a) What is the mass (in kg) that the Sun loses each…

A:

Q: Stellar Classification and H-R Diagram Placement (40 points available). a. Where is your star…

A: ..

Q: A bright red star is moving towards Earth. Which of the choices best completes the following…

A: Answer : - option D is correct. Explanation It is absorption because it is continuous spectrum,…

Q: a) Sketch a generic HR diagram, including labels for the axes. (Take a picture or scan your work and…

A: a) HR diagram is,

Q: Based on what you know about main-sequence stars, select all of the correct statements from the…

A: Required : Correct statements .

Q: Based on what you learned about stellar evolution, select all of the correct statements from the…

A: 1. Correct: From the studies, it has been found that the period of some Cepheid variables actually…

Q: What are the on the axes of a Hertzsprung-Russell diagram? (b) Name one thing you can tell about a…

A: Hertzsprung-Russell Diagram plots the temperature of the start against their luminosity (or) colour…

Q: What do these three nebulae have in common? NOTE: There are multiple correct answers. Select all…

A: (1) As we know that Nebulae are made of dust and gases mostly hydrogen and helium. (2) The dust and…

Stellar evolution

We may see thousands of stars in the dark sky. Our universe consists of billions of stars. Stars may appear tiny to us but they are huge balls of gasses. Sun is a star of average size. Some stars are even a thousand times larger than the sun. The stars do not exist forever they have a certain lifetime. The life span of the sun is about 10 billion years. The star undergoes various changes during its lifetime, this process is called stellar evolution. The structure of the sun-like star is shown below.

Red Shift

It is an astronomical phenomenon. In this phenomenon, increase in wavelength with corresponding decrease in photon energy and frequency of radiation of light. It is the displacement of spectrum of any kind of astronomical object to the longer wavelengths (red) side.