Henrietta Leavitt Calibrates the Stars
27.10.1998

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.

A Prominent Solar Prominence
27.01.1997

One of the most spectacular solar sights is a prominence. A solar prominence is a cloud of solar gas held above the Sun's surface by the Sun's magnetic field. The Earth would easily fit under one of the loops of the prominence shown in the above picture.

Dusty Galaxy Centaurus A
30.03.1997

One of the most unusual galaxies known, Centaurus A, is pictured above. Cen A is marked by dramatic dust lanes that run across the galaxy's center. These dust lanes are so thick they almost completely obscure the galaxy's center in visible light.

Dusty Galaxy Centaurus A
28.08.1995

One of the most unusual galaxies known, Centaurus A, is pictured above. Cen A is marked by dramatic dust lanes that run across the galaxy's center. These dust lanes are so thick they almost completely obscure the galaxy's center in visible light.

Infrared Trifid
28.08.1997

The Trifid nebula (M20) is a bright star forming region in Sagittarius, 5000 light years from Earth. In visible light, the interstellar gas cloud is crossed by dark, obscuring dust lanes which roughly divide the glowing emission nebula into three major parts.

M13: The Great Globular Cluster in Hercules
19.08.1998

M13 is one of the most prominent and best known globular clusters. Visible with binoculars in the constellation of Hercules, M13 is frequently one of the first steps beyond the ordinary visible to the casual sky gazer.

Unusual M82: The Cigar Galaxy
15.03.1998

Something strange happened to this galaxy, but what? M82 is a nearby galaxy in the group of galaxies dominated by itself, M81, and NGC 3077. M82 is thought by some to be limping away from a close encounter with M81.

Galaxy in a Crystal Ball
22.06.2018

A small crystal ball seems to hold a whole galaxy in this creative snapshot. Of course, the galaxy is our own Milky Way. Its luminous central bulge marked by rifts of interstellar dust spans thousands of light-years. On this long southern hemisphere night it filled dark Chilean skies over Paranal Observatory.

Unusual M82: The Cigar Galaxy
18.11.1996

Something strange happened to this galaxy, but what? M82 is a nearby galaxy in the group of galaxies dominated by itself, M81, and NGC 3077. M82 is thought by some to be limping away from a close encounter with M81.

Pillar at Sunset
6.03.2010

Reddened light from the setting Sun illuminates the cloud banks hugging this snowy, rugged terrain. Inspiring a moment of quiet contemplation, the sunset scene included a remarkable pillar of light that seemed to connect the clouds in the sky with the mountains below.