View larger. | Fomalhaut is sometimes called lonely because no other bright stars shine near it in the sky. Photo by EarthSky Facebook friend Tony Gieracki. Thank you, Tony!
Meet Fomalhaut, a bright star and one of the easiest stars to find at this time of year. It usually appears solitary, but in 2019 Fomalhaut has company: Jupiter and Saturn. Plus Fomalhaut has a place in astronomical history. Orbiting it is the world's first visible exoplanet. All in all, Fomalhaut is a star you'll want to know. How to see Fomalhaut and contemplate its planet.
We have an equinox coming up on September 23. For us in the Northern Hemisphere, the sun is rising later now, and nightfall comes sooner. At the equinox, days and nights will be approximately equal in length. As we enjoy the cooler days of almost-autumn, spring is about to begin for our friends south of the equator. Here's all you need to know.
Carbon dioxide, CO2, makes up less than one-twentieth of 1% of Earth's atmosphere. How does this relatively scarce gas control Earth's thermostat? An environmental scientist explains.
View larger. | The Hubble Space Telescope’s Wide Field Camera 3 observed Saturn on June 20, 2019. That was shortly before Earth flew between Saturn and the sun on July 9, and thus Saturn was generally at its closest to Earth for this year, at nearly a billion miles (1.36 billion km) away. Image via NASA/ESA/A. Simon/M.H. Wong/Spacetelescope.org. You can see Saturn in the evening sky. Click for EarthSky's September planet guide.
