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Astronomy/Dark matter and Dark energy


Hello. I am doing a project on dark matter and dark energy for astronomy nine and I was wondering if you could be of any help. A lot of the websites I have visited have been rather vague.  Could you do me a big favour and tell me what are some important and/or interesting facts about dark matter and dark energy? Thank-you in advance.

Dark matter and dark energy make up 95% of the Universe.  Even though the have the same name, they are not related.  

Dark matter is some sort of mass that makes up most of the mass of galaxies, causing galaxies to spin faster than predicted with standard physics.  The leading theory is a WIMP, a Weakly Interactive Massive Particle - a subatomic particle that doesn't interact with light but is very heavy.  Experiments such as the Large Hadron Collider (LHC) at CERN in Switzerland are trying to find it.

Dark energy on the other hand is causing the Universe to accelerate in its expansion.  There are many theories on what it could be.  It could be the inherent energy of empty space, vacuum energy, causing the Universe to expand.  Another theory is a new force or energy, that changes with time.

The really cool thing is that the Universe actually slowed down in its growth before it sped up.  This is because gravity slowed down the growth of the Universe, but as it still was expanding, the strength of dark energy overcame the strength of gravity and caused the Universe to start speeding up.  Eventually dark energy will cause the Universe to end, in either the Big Rip or the Big Freeze.  


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Brad Tucker


I'm happy to answer any general questions about Astronomy, Astrophysics, and Cosmology. I'm also happy to take general, specific, and detailed questions related to supernovae, Baryonic Acoustic Oscillations, the Cosmic Microwave Background, dark matter, dark energy, and the Big Bang Theory. I'm also happy to chat about Astronomy/Astrophysics education and careers, and philosophy and science.


I am a professional research astronomer/astrophysicist/cosmologist. My research focuses on studying supernovae and using them to measure the properties of the Universe, such as how fast it is growing and what it is made of. I also frequently give talks to school groups and the public, and am a regular guest on various radio stations.

Current Research Fellow at Mt. Stromlo Observatory, the Australian National University, and in the Department of Astronomy, University of California, Berkeley.

Lots of journals, including the Astrophysical Journal, the Astronomical Journal, and Nature. I am currently in the middle of writing my first popular book.

B.A. Philosophy, University of Notre Dame, Notre Dame, IN USA B.A. Theology, University of Notre Dame, Notre Dame, IN USA B.Sc. Physics, University of Notre Dame, Notre Dame, IN USA Ph.D. Astrophysics, Mt. Stromlo Observatory, the Australian National University, Canberra, ACT, Australia

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