A large comet is approaching the Earth and is getting brighter

For the past 3 million years, comet C/2017 K2 (PanSTARRS) has been approaching the Sun, making a long, slow journey from the outer Solar system. Finally, she's here. 

Michael Jaeger photographed her on June 25 from Martinsberg, Austria.

"It's a 22-minute exposure with my 16-inch telescope," says Yeager. "The comet was about the 9th magnitude."

"Comet K2" made a splash when it was discovered in 2017. At first it seemed to be one of the largest comets in modern history, with a core 160 km wide. Subsequently, observations of the Hubble Space Telescope made it possible to reduce the comet to 18 km. This is still a large size (typical sizes of cometary nuclei are 1-3 km), but not a record holder.

The comet will make its closest approach to Earth (at a distance of 1.8 AU) on July 14 and will become brighter to the 7th or 8th magnitude. It's too dim to see with the naked eye, but it's an easy target for yard telescopes. Comet K2 can be found high in the midnight sky in the constellation of Ophiuchus.