David N. Schramm 1945-1997

1997-12-22

David N. Schramm effectively combined the very big with the very small. Among his many scientific achievements, Schramm and collaborators successfully used Big Bang cosmology to predict that only three families of elementary particles exist in ...

A Winter Solstice

1997-12-21

Today is the Winter Solstice, the shortest day of the year in the Northern Hemisphere. The yearly cycle of Seasons on planet Earth once again finds the Sun at its lowest point in the Northern Sky. The Sun's own 11 year cycle of activity is ...

Apollo 16: Exploring Plum Crater

1997-12-20

Apollo 16 spent three days on Earth's Moon in April 1972. The fifth lunar landing mission out of six, Apollo 16 was famous for deploying and using an ultraviolet telescope as the first lunar observatory, and for collecting rocks and data on the ...

NGC 6826: The Blinking Eye

1997-12-19

The colorful planetary nebula phase of a sun-like star's life is brief. Almost in the "blink of an eye" - cosmically speaking - the star's outer layers are cast off, forming an expanding emission nebula. This nebula lasts perhaps 10 thousand ...

Gamma-Ray Burster

1997-12-18

Gamma-ray bursts seem to be the most powerful explosions in the Universe. Yet their sources continue to elude researchers who stand in awe and frustration at the bursts' transient, enigmatic behavior. The blinking gif above illustrates the latest ...

Stonehenge: Ancient Monument to the Sun

1997-12-17 Clive Ruggles

Stonehenge consists of large carved stones assembled about 4000 years ago. Long before modern England was established, ancient inhabitants somehow moved 25 ton rocks nearly 20 miles to complete it. From similar constructs of the era, people ...

Night Lightning on Jupiter

1997-12-16

Why is there lightning on Jupiter? Lightning is a sudden rush of electrically charged particles from one location to another. To create lightning, charges must first separate inside a cloud. On Earth, drafts of colliding ice and water droplets ...

A Farewell to Tails

1997-12-15 W. Pacholka

As 1997 fades, so does the Great Comet of 1997: Comet Hale-Bopp. Discovered even before the Great Comet of 1996, Comet Hale-Bopp became the brightest comet since 1976. Many will remember Comet Hale-Bopp as a comet with a coma so bright it could ...

The Radio Sky: Tuned to 408MHz

1997-12-14

Tune your radio telescope to 408MHz (408 million cycles per second) and check out the Radio Sky! You should find that frequency on your dial somewhere between US broadcast television channels 13 and 14. In the 1970s large dish antennas at three ...

The Coma Cluster of Galaxies

1997-12-13

Almost every object in the above photograph is a galaxy. The Coma Cluster of Galaxies pictured is one of the densest clusters known - it contains thousands of galaxies. Each of these galaxies house billions of stars - just as our own Milky Way ...