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Course: American Museum of Natural History > Unit 2
Lesson 4: Universe- The Universe
- The Known Universe
- Exploring the Dark Universe: Dark matter
- Will Dark Energy Please Come to Light?
- Exploring the Dark Universe: Dark energy
- The Cosmic Microwave Background
- The Cosmic Microwave Background: A New View From the South Pole
- Our Expanding Universe
- Universe Glossary
- Quiz: Universe
- Exploration Questions: Universe
- Answers to Exploration Questions: Universe
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The Known Universe
The known Universe takes viewers from the Himalayas through our atmosphere and the inky black of space to the afterglow of the Big Bang. Every star, planet, and quasar seen in the film is possible because of the world's most complete four-dimensional map of the universe, the Digital Universe Atlas that is maintained and updated by astrophysicists at the American Museum of Natural History. Created by American Museum of Natural History.
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What's beyond the universe? An infinite range of darkness? Does the universe even ever end? An infinite range of whiteness? What's beyond that infinite range of black or white?(2 votes)
Short answer: We don't know.
We are not even sure if this universe is infinite or not.
Space is curved, so if the Universe has an end you're more likely to eventually come back to your starting point than to drop out of the Universe. Then again you have the idea of an multiverse - an infinite number of coexisting universes in different dimensions.
If the Universe is infinite, then maybe we'll get infinite darkness (no stars - no light - darkness), or maybe the darkness will be punctuated by an infinite number of Big Bangs...
Sooo, yeah. We don't know.(2 votes)
how do planets keep almost the same orbit all the time(1 vote)
This is because of the sun spinning & the gravity on the sun causes us to orbit & so we stay on the same track of orbit cause of our earth spinning as well & the earth sonly spinning cause of revolution.(3 votes)
How do you know the universe is so big?(1 vote)
What is The Unknown Universe?(1 vote)
How did the big bang happen?(1 vote)- What all quality should we have to become a astronaut(1 vote)
Engineering or scientific training, piloting experience, luck(1 vote)
- If e=mc² and light has no mass and we try to measure the energy within light we get...e=0xmc². The answer is that light has no energy.But we know this is wrong, and since einstien was the one who described the photovoltaic effect he also knew this was wrong...If light has energy and light also has mass then how does it travel the speed of light since nothing with mass can reach the speed of light as explained by einstien based on the logic of a closed a closed universe? This equation seems highly flawed and inadequate considering nearly everything we know about the universe is based upon observations of light. Do physicists actually still use this equation and why?(1 vote)
That is actually only part of the equation and just the part that deals with rest mass. The full equation is: E = mc²+pc
In this equation, m = rest mass. For light, you are correct that it equals 0. So, the equation simplifies to E=pc, where p = momentum.
From there, we can see that p = mv, where v is velocity and, while m is also mass, it is actually relative mass, or I'll abbreviate m(rel).
Since we know that v for light equals c, Einsteins equation further simplifies now to E = pc = m(rel)vc = m(rel)c². Thus light, via its momentum, has a relative mass directly proportional to its energy.(1 vote)
My mind exploded! someone call a neurosurgeon!(1 vote)
It's weird because we have only explored two sides of our expanding, creating, exploding, shrinking universe.(1 vote)- Is the universe going to explode(1 vote)
- Measurements to determine whether Dark Energy is strong enough to drive a Big Rip in billions of years are ongoing. So far they are inconclusive, with the increasingly accurate answers hovering right on the edge.(1 vote)