The Bullet Cluster, the aftermath of a galaxy cluster collision that occurred 3.8 billion years ago in a region of space located ~3.7 billion light-years away, represents very strong evidence for the existence of dark matter. The separation of the...
In 1977, NASA’s Voyager 1 and 2 spacecraft began their pioneering journey across the Solar System to visit the giant outer planets. Now, the Voyagers are hurtling through unexplored territory on their road trip beyond our Solar System. Along the...
This photo shows the bright, naked-eye star, Albireo. To the naked eye, it appears as just a single point of light. However, a binocular or telescope view shows that it’s actually two very different colored stars separated by a substantial...
At the start of the hot Big Bang, the Universe was rapidly expanding and filled with high-energy, very densely packed, ultra-relativistic quanta. An early stage of radiation domination gave way to several later stages where radiation was sub-dominant, but still...
All across the world, fireworks displays mark a variety of holidays and celebrations, with many of the most spectacular displays occurring annually on July 4th in the United States. Although there’s a lot of science involved in putting on a...
What do planets outside our solar system, or exoplanets, look like? A variety of possibilities are shown in this illustration. Scientists discovered the first exoplanets in the 1990s. As of 2024, the tally stands at over 5,000 confirmed exoplanets. None...
In 1896, Einstein was admitted into Zurich Polytechnic Institute, where he would graduate in 1900 4th in his graduating class of 5. Although he was held in low esteem by the most famed and prestigious of his professors, he would...
This remarkable three-panel image showcases the same region of space: the Pillars of Creation. On the left, the 1995 Hubble view is shown. At center, the follow-up 2014 Hubble image, with an upgraded instrument suite, is presented. At right, the...
This panorama of three different sunrises: during Summer solstice (left), equinox (middle), and Winter solstice (right). Note not only the difference in the Sun’s location, but also the shape of its rising path, between the three cases. (Credit: LynceanEducation/Wikimedia Commons)Sure,...
By examining this strobe image of a bouncing ball, you cannot tell for certain whether the ball is moving towards the right and losing energy with each bounce, or whether it’s moving towards the left and getting an energetic kick...
