NGC 6357: Cathedral to Massive StarsHow massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, making it one of the most massive stars known. This star is the brightest object located in the central cavity near the…Read More

Equinox at SaturnOn Saturn, the rings tell you the season. On Earth, today marks an equinox, the time when the Earth’s equator tilts directly toward the Sun. Since Saturn’s grand rings orbit along the planet’s equator, these rings appear most prominent — from the direction of the Sun — when the spin axis of Saturn points toward the Sun.…Read More

Equinox SunsetDoes the Sun set in the same direction every day? No, the direction of sunset depends on the time of the year. Although the Sun always sets approximately toward the west, on an equinox like today the Sun sets directly toward the west. After tomorrow’s September equinox, the Sun will set increasingly toward the southwest, reaching its…Read More

Gibbous vs Crescentrly risers around planet Earth have enjoyed a shining crescent Moon near brilliant Venus, close to the eastern horizon in recent morning twilight skies. And yesterday, on September 19, skygazers watching from some locations in Earth’s northern hemisphere were also able to witness Venus, in the inner planet’s waxing gibbous…Read More

The NGC 6914 ComplexA study in contrasts, this colorful cosmic skyscape features stars, dust, and glowing gas in the vicinity of NGC 6914. The interstellar complex of nebulae lies some 6,000 light-years away, toward the high-flying northern constellation Cygnus and the plane of our Milky Way Galaxy. Obscuring interstellar dust clouds appear in…Read More