https://padlet.com/0908211/5f0ihqzhrzzu by Zachary Johnson en-us 2020-03-13 14:59:59 UTC 2020-03-14 01:42:46 UTC hello@padlet.com https://padlet.net/icons/png/1f4a5.png 0908211 https://padlet.com/0908211/5f0ihqzhrzzu/wish/460049354 The acceleration of the expansion of the Universe can be explained by a mysterious force dubbed dark energy. Dark energy is a repulsive force that works against gravity, preventing the it from slowing down or even reversing the Universe's expansion

]]> 2020-03-13 15:02:16 UTC https://padlet.com/0908211/5f0ihqzhrzzu/wish/460049354 0908211 https://padlet.com/0908211/5f0ihqzhrzzu/wish/460060394 Albert Einstein first came up with the idea that outer "space" had a special energy which caused the "space" to multiply.  And he theorized that this energy was a natural property of space, so it would continue to spread. It was later presented as "dark energy" in 1998, as a force that repels gravity. Dark energy currently takes up about 69% of the universe, continuing to multiply, and accelerate the expansion of the universe.]]> 2020-03-13 15:13:56 UTC https://padlet.com/0908211/5f0ihqzhrzzu/wish/460060394 0908211 https://padlet.com/0908211/5f0ihqzhrzzu/wish/460393836 We can tell that the expansion of the Universe has sped up over time by observing supernovas different distances away and plotting its speed over time...By examining something as big and bright as a supernova, we can look really far into the past. So if we were to look at a supernova further away from us and compare it to supernovas significantly closer, we can plot to find out if its speed (calculated by red shift) has increased or not over time (calculated by the brightness of it, brighter meaning closer, dimmer meaning further.) Scientists that have plotted this have found that the Universe is expanding faster today than long ago. This proves that the expansion of the Universe is accelerating.]]> 2020-03-14 00:11:42 UTC https://padlet.com/0908211/5f0ihqzhrzzu/wish/460393836 0908211 https://padlet.com/0908211/5f0ihqzhrzzu/wish/460396785 We can calculate the speed of a star or supernova moving away from us by its color. If the star is x% redder than it normally would be at its distance from Earth, it's moving away from us at x% the speed of light. The redder the star/supernova, the faster its moving away from us.]]> 2020-03-14 00:22:27 UTC https://padlet.com/0908211/5f0ihqzhrzzu/wish/460396785 0908211 https://padlet.com/0908211/5f0ihqzhrzzu/wish/460398374 We can calculate a star's or supernova's distance from Earth by it's brightness. Basically, the brighter it is, the closer it is to us. Like the sun, if it were closer, we would be blinded by its light. It's as simple as that. But why does the distance matter other than to calculate the red shifting? Light takes time to reach us, so by calculating the distance of the star/supernova/galaxy, we can tell how far in the past we're seeing. The dimmer it is, the further the distance, and the further in the past we're seeing.]]> 2020-03-14 00:28:35 UTC https://padlet.com/0908211/5f0ihqzhrzzu/wish/460398374 0908211 https://padlet.com/0908211/5f0ihqzhrzzu/wish/460413074 2020-03-14 01:26:01 UTC https://padlet.com/0908211/5f0ihqzhrzzu/wish/460413074 0908211 https://padlet.com/0908211/5f0ihqzhrzzu/wish/460416590 2020-03-14 01:41:00 UTC https://padlet.com/0908211/5f0ihqzhrzzu/wish/460416590