Our Sun is one star among billions of stars in the Milky Way. However, it is difficult to determinethe exact number of stars. By observing the nearby stars around us, you find that the local den-sity of stars is 0.05 stars/(light-year)3. For simplicity, assume that the Milky Way has a cylindricalshape with a diameter of 100,000 light-years and a thickness of 1,000 light-years.Use this information to estimate the total number of stars in the Milky Way

how many stars are in the galaxy

Our galaxy contains ________ stars. *1 pointtwo hundred billiontwo hundred trillion starstwo hundred million starsan unknown number of starsThe galaxy(ies) that we can see from New Jersey with the naked eye is*1 pointLarge Magellanic cloudSmall Magellanic cloudAndromedaOuter edges of galaxies containing individual stars, gas, and dust is called *1 pointThe discThe haloThe bulgeThe armsThree main galaxy shapes include ... *1 pointSphericalEllipticalSpiralPinwheelIrregularPeculiarGalaxies contain hot, bright stars that live shorter lives which appear ______ in color and cool dim stars that live longer lives that appear _______ in color.*1 pointyellow, bluered, blueblue, redyellow, redblue, yellowLarger elliptical galaxies can be _________ of lightyears across*1 point1,000's10,000's100,000's1,000,000'sMost galaxies are named ...*1 pointCreatively like "andromeda" or "milky way"By a cataloguing system with letters and numbersAfter the person who discovered themRandomlyElliptical galaxies range from being very spherical, ______, to being very elongated, _____. *1 pointE0, E7E1, E6S, ESome spiral galaxies have a bar in the middle and are called *1 pointBlocked spiralsBarred spiralsBig spiralsBulky spiralsObserved Irregular galaxies are *1 pointYoungMiddle agedOldSpirals like the milky way are... *1 pointYoungMiddle ageOldSupermassive black holes are commonly found in *1 pointThe older galaxiesThe edges of galaxiesThe centers of galaxiesThe galaxy arms

If each galaxy contains 1 hundred billion stars, and there are 1 hundred billion galaxies, and 89% of all stars are low mass like the Sun, and 1 in 5 low mass stars like the Sun have planets like Earth in the habitable zone, what is the number of planets that exist in the Universe that are in the habitable zones of their low mass stars? (hint: use your favorite, dimensional analysis! try this on paper!)  Start with 1 Universe, then convert to galaxies and so on. (For 89% use this conversion factor: 89 low mass stars /100 stars)*1 point4.88 x 10^28 planets2.99 x 10^18 planets8.93 x 10^15 planets1.78 x 10^21 planets

Deneb, one of the most luminous stars as viewed from Earth, has a solar mass of 20 and solar radii of 250Which of the following accurately describes the star Deneb?Deneb is 250 times farther away than the Sun.Deneb has 250 times the mass of the Sun.Deneb is 20 times the mass of the Sun.Deneb has 20 times the volume of the Sun.

Scientists have developed a basic model for the Milky Way to describe the density distribution ofstars ρ(r) at distance r from the center by evaluating the three regions A, B, C:ρ(r) = Ψ ·[exp(ΩA − rRA)+ exp(ΩB − rRB)+ exp(ΩC − rRC)]The model parameters have the values below:Ψ = 10−4 stars/(light-year)3RA = 20 light-yearsRB = 12 · 103 light-yearsRC = 5 · 104 light-yearsΩA = 21, ΩB = −3, ΩC = −8(b) Create a double logarithmic plot of the density distribution ρ(r) with respect to r.(c) Using this model, calculate the number of stars in the Milky Way (r ≤ 130,000 light-years).Note: Assume that the Milky Way has a constant thickness of 1,000 light-years