The Remarkable Discoveries of Fritz Zwicky

Zwicky was first to discover galaxies form in clusters - small portion of Coma Galaxy Cluster shown here. NASA Image by Hubble.

Fritz Zwicky was the first astronomer to propose the existence of dark matter, supernovas, neutron stars, galactic cosmic rays, gravitational lensing by galaxies, and galaxy clusters. However, he remains virtually unknown to the public to this day.

Henrietta Swan Leavitt: Unsung Female Science Pioneer Lauded On Stage

leavitts law helps us measure the universe

Will an unsung astronomy pioneer, Henrietta Swan Leavitt, finally get the credit she deserves? In 1895 Henrietta Swan Leavitt volunteered as an unpaid assistant at Harvard College Observatory. Her work on Cepheid variable stars led to the discovery of galaxies beyond our Milky Way, the expansion of the universe, and the big bang. Leavitt’s Law […]

The Search for Dark Matter: Largest Survey Ever

Dark-Matter-Galaxy-Clusters1-300x225

An¬†international team of astronomers generated the largest map yet of the most abundant (and most mysterious) form of matter in our universe — dark matter. Results support the view that this invisible substance is the cosmic glue which holds galaxies and clusters of galaxies together. Unseen Matter and the Motion of Galaxies In 1933, Swiss/American […]

Will 2012 Be the Year of the Solar Storm?

Is there a danger from 2012 coronal mass ejections (CME) or solar storms? Image courtesy of NASA/JPL

The Question: Will 2012 be the year of the solar storm? Stories about “Solar Max” and electric gadget-frying-levels of solar flares are running high in the rumor mill. What is the truth about the solar maximum and solar storms in 2012? The short answer is: 2012 is will probably not be the “Year of the […]

Reionization and Satellite Galaxies to the Milky Way

Milky Way is a spiral galaxy: Image by NASA

The Milky Way galaxy has a number of small satellite, or companion, dwarf elliptical galaxies orbiting it. Many astronomers, however, think that the Milky Way should have more satellite galaxies than it does. A theory recently proposed by Pierre Ocvirk and Dominique Aubert of the Strasbourg Observatory in France tries to explain this shortage. They […]

Close Encounter with Asteroid 2005 YU55 November 8, 2011

Trajectory of asteroid 2005 YU55 - Image credit: NASA/JPL-Caltech

On November 8, 2011, the small near-Earth asteroid, 2005 YU55, will pass within about 85% of the distance between Earth and Moon from Earth. At its closest approach, asteroid 2005 YU55will be about 325,000 kilometers (202,000 miles) from Earth’s center. Asteroid 2005 YU55: The Approach This approach is quite close by astronomical standards, but the […]