2MASS J17554042 6551277
18.03.2022

2MASS J17554042+6551277 doesn't exactly roll off the tongue but that's the name, a coordinate-based catalog designation, of the star centered in this sharp field of view. Fans of the distant universe should get used to its spiky appearance though.

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.

LP 944-20: A Failed Star Flares
13.07.2000

The tiny spot circled on the right actually represents a big astronomical discovery -- the first detected flare from a failed star. Failed stars, termed brown dwarfs in astronomers' parlance, are too low in mass to ignite nuclear hydrogen burning in their cores, yet

Active Regions, CMEs, and X Class Flares
8.06.2000

Space Weather forcasters are predicting major storm conditions over the next few days as the active Sun has produced at least three strong flares and a large coronal mass ejection (CME) since Tuesday, June 6th.

Why Stars Twinkle
25.07.2000

This is what a star really looks like from the surface of the Earth. To the best the human eye can see, stars are so far away they appear the same as would infinitesimal points of light.

The 25 Brightest Stars in the Night Sky
17.12.2022

Do you know the names of some of the brightest stars? It's likely that you do, even though some bright stars have names so old they date back to near the beginning of written language.

Sunspot 875 Flares
2.05.2006

An unusually active sunspot region is now crossing the Sun. The region, numbered 875, is larger than the Earth and has produced several solar flares over the past week. It should take a few more days for Sunspot 875 to finish crossing the solar disk.

Solar Flares Cause Sun Quakes
1.06.1998

An 11th magnitude quake has been recorded on the Sun, immediately following a moderate solar flare. The quake was the first ever recorded on the Sun, but only because astronomers have only recently figured out when and how to find them using the orbiting SOHO spacecraft.

Small Star
5.06.1997

A dim double star system cataloged as Gliese 623 lies 25 light-years from Earth, in the constellation of Hercules. The individual stars of this binary system were distinguished for the first time when the Hubble Space Telescope's Faint Object Camera recorded this image in June 1994.

Neutron Star Earth
16.06.1995

If the Earth could somehow be transformed to the ultra-high density of a neutron star , it might appear as it does in the above computer generated figure. Due to the very strong gravitational field, the neutron star distorts light from the background sky greatly. If you look closely, two