Supernovaes

Dark energy makes up most of our universe. Every object out in space is bound to interact with it at one point or another because it is claimed to be the cause of the expansion of the universe. The dark energy pushes objects further apart in space and making astronomers want to learn more and more about this mysterious dark energy. Astrophysicists first discovered cosmic acceleration by examining the apparent brightness of tens of distant Type Ia supernovae, exploding stars that briefly become as bright as an entire galaxy of billions of stars. There is a Dark Energy Survey that will continue to examine this further by finding and making detailed measurements of several thousand supernovae. To determine the distances to these stars, cosmologists use the fact that Type Ia supernovae are nearly "standard candles": exploding stars of this type all have nearly the same absolute brightness or luminosity when they reach their brightest phase. By comparing the apparent brightness of two supernovae, we can then determine their relative distances. What is causing this distance is the dark energy pushing them further and further apart.   
                                                
                                               http://www.darkenergysurvey.org/images/sn94d-1.jpg

                                                

 http://i1-news.softpedia-static.com/images/news2/Understanding-the-Origin-of-Type-Ia-Supernovae-2.jpg

References:

1.       "What is Dark Energy?", Nola Taylor Redd, http://www.space.com/20929-dark-energy.html

2.       “Big Bang: How Did the Universe Begin?”, Yuki D. Takahashi, Spring 2000, http://www.ugcs.caltech.edu/~yukimoon/BigBang/BigBang.htm

3.         “Dark Energy, Dark Matter”, NASA Official: Ruth Netting, April 30, 2013, science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/