|
Astronomy Picture Of the Day (APOD)
IC 418: The Spirograph Nebula
7.09.2000
What is creating the strange texture of IC 418? Dubbed the Spirograph Nebula for its resemblance to drawings from a cyclical drawing tool, planetary nebula IC 418 shows patterns that are not well understood. Perhaps they are related to chaotic winds from the variable central star, which changes brightness unpredictably in just a few hours.
Emerging Planetary Nebula CRL 618
6.09.2000
CRL 618 may look to some like an Olympian declaring victory. Only a few hundred years ago, however, CRL 618 appeared as a relatively modest red giant star. Since then it has run out of core material to fuse and so has started to become a planetary nebula.
CFHT Star Trails
5.09.2000
High atop a dormant volcano in Hawaii, an eye 3.6-meters wide stares at a faint light on the night sky. Unlike a human eye, which collects light for only a fraction of a second at a time, a telescope such as the Canada-France-Hawaii Telescope (CFHT) can collect light for hours.
Aurora Persei
4.09.2000
Last month, skywatchers were treated to an unexpected coincidence: bright aurorae occurred during the Perseid Meteor Shower. The above picture was taken August 12 and captures eerie looking aurorae and a faint Perseid meteor above Cross Lake in Wisconsin, USA. The near future holds promise for both more aurorae and a better meteor shower.
Henrietta Leavitt Calibrates the Stars
3.09.2000
Humanity's understanding of the relative brightness and variability of stars was revolutionized by the work of Henrietta Swan Leavitt (1868-1921). Working at Harvard College Observatory, Leavitt precisely calibrated the photographic magnitudes of 47 stars to which all other stars could be compared.
X Ray Moon
2.09.2000
This x-ray image of the Moon was made by the orbiting ROSAT (Röntgensatellit) Observatory in 1990. In this digital picture, pixel brightness corresponds to x-ray intensity. Consider the image in three parts: the bright hemisphere of the x-ray moon, the darker half of the moon, and the x-ray sky background.
SOHO Sungrazer
1.09.2000
SOHO, the space-based SOlar and Heliospheric Observatory, has become by far the reigning champion facility for discovering comets, its total having recently reached 200. As might be expected of a solar observatory, most of the SOHO discovered comets are sungrazers, destined to dive within a mere 50 thousand kilometers or so of the solar photosphere.
Full Throttle For Deep Space 1
31.08.2000
At full throttle the Deep Space 1 spacecraft's innovative ion drive produces about 1/50th of a pound of thrust ... a force so great that it would just about hold up a piece of paper on planet Earth! Still, powered by solar arrays ion propulsion systems can run continuously.
The Brown Dwarfs of Orions Trapezium
30.08.2000
The bright stars above are well known as heart of the Trapezium, an open cluster of stars in the center of the Orion Nebula. The many dim objects, however, are not well known, and have come to attention only on recent images in infrared light.
The Regolith of Asteroid Eros
29.08.2000
From fifty kilometers above asteroid Eros, the surface inside one of its largest craters appears covered with an unusual substance: regolith. The thickness and composition of the surface dust that is regolith remains a topic of much research.
|
January February March April May June July August September October November December |
|||||||||||||||||||||||||||||||||||||||||||||||||