Proxima Centauria. When was it discovered? 1915b. Why is it important? Because it is the closest star to our sun.c. How large is it? d. How far away is it? 4.22 light years away from the sun, and 4.243 light years away from the earthe. What type of star is it? The mass of this star is 0.1 times the Sun, and its radius is probably about 1/2 that of the Sun or so.f. Is it a threat to life on Earth? The star itself wont approach close.However, our Oort cloud extends some distance from the Sun, and the centauries probably have a cloud of their own. As these are quite some way from the sun, it might be possible for their orbits to be affected.g. Anything else you find interesting about it? The star can be found in the Centaurus constellation, a centaur is a Greek mythological half man half horse creature, proxima is Latin for next or nearest.

The Crab Pulsara. When was it discovered? Widely observed on Earth in the year 1054. Discovered in 1968.b. Why is it important? It emits more than 100 giga-electron volts of gamma rays, 100 billion times more energetic than visible light.c. How large is it? The pulsars diameter is about 20 kilometres, but its mass is many times larger than that of our sun.d. How far away is it? about7000 light yearsaway in the constellatione. What type of star is it? Is asupernova remnantandpulsar wind nebulain theconstellationofTaurus.f. Is it a threat to life on Earth? The pulsar emits gamma radiation in certain directions as an indirect consequence of its strong magnetic field the exact mechanism is unclear. Because the pulsar rotates thirty times a second, we on the earth measure the radiation as light pulses with the corresponding periodicity.g. Anything else you find interesting about it? In the summer of 1967, U.S. Air Force officer Charles Schisler was on radar duty at Clear Air Force Base in Alaska when he noticed a fluctuating radio source. The source appeared over the course of several days, and Schisler noticed that its position coincided with the Crab Nebula. However, the findings weren't published by the Air Force at the time, and the discovery went unrealized until 2007.

Eta Carinae:a. When was it discovered? Discovered in 1677b. Why is it important? Important because several x-ray and gamma-ray sources.c. How large is it? Size: 32.6R0d. How far away is it? 7,500 light-years from the Sune. What type of star is it? Luminous blue variable.f. Is it a threat to life on Earth?g. Anything else you find interesting about it?

Betelgeuse:a. When was it discovered? Discovered in 1836b. Why is it important? Ninth brightest star in the night sky and second brightest in the constellation of Orionc. How large is it? 950~1200 R0

d. How far away is it? 180 lights years from the sune. What type of star is it? II supernovaf. Is it a threat to life on Earth?g. Anything else you find interesting about it?

Cygnus X-11. When was it discovered? Discovered 1964, 1. Why is it important? Strong Black hole candidate1. How large is it? Radius: 20-22 Solar radius1. How far away is it? 6100 light years1. What type of star is it? X-ray source / potential black hole1. Is it a threat to life on Earth? Black hoes full potential is yet to be known so it could be.Anything else you find interesting about it? There was a bet between Stephen Hawking and Kip Thorne on if it was a black hole or not.

51 Pegasi1. When was it discovered? October 6 19951. Why is it important? First sun like star with a planet around it.1. How large is it? 1.237 solar radii1. How far away is it? 50.9 light years away1. What type of star is it? Same as our star.1. Is it a threat to life on Earth? No.1. Anything else you find interesting about it? Visible with the naked eye.

Alpha Ursae Minoris1. When was it discovered? ~1601. Why is it important? Used a lot for sea travel because it pointed to compass north.1. How large is it? 46 Solar radii1. How far away is it? 375 light year1. What type of star is it? It is made up off multiple stars, the main one being a supergiant.1. Is it a threat to life on Earth? No.1. Anything else you find interesting about it? 45th brightest star in the sky, brightest star of Ursa Minor constellation.