Astronomers have discovered that a Neptune-sized exoplanet – HAT-P-11b – has an even larger helium atmosphere than first thought. The atmosphere is literally inflated like a massive balloon.
Artist’s concept of the exoplanet HAT-P-11b with its extended helium atmosphere blown being out into space by stellar radiation from the star. Image via Denis Bajram.
Comet 46P/Wirtanen is making one of the 10 closest comet flybys of Earth in 70 years today. Whether you glimpse it with the eye – or see it online – don’t miss this comet! Charts, tips and other info here.
Greg Hogan in Kathleen, Georgia caught Comet Wirtanen on February 26, 2018. He wrote: "This comet was FINALLY over my tree line of my neighborhood. Here is a shot I got with my 85mm lens on a Canon 7D. I was able to find it quickly with just a quick shot pointed in the right direction. Taken 9:30pm EST." Canon 7D, 85mm, 5-sec exposure, ISO 6400, f2.8.
Sun pillars, or light pillars, are shafts of light extending from the sun or other bright light source. They’re caused by ice crystals drifting in Earth’s air.
Michael Busch captured this pair of photos on December 12, 2018 and wrote: "Incredible sun pillar above and then below the sun. Fire Island, New York."
December solstice 2018 arrives on December 21 at 22:23 UTC. High summer for the Southern Hemisphere. For the Northern Hemisphere, the return of more sunlight!