The Long Tails of Comet NEOWISE

This Comet NEOWISE (C/2020 F3) now sweeps through our fair planet’s northern skies. Its long tails stretch across this deep skyview from Suchy Vrch, Czech Republic. Recorded on the night of July 13/14, the composite of untracked foreground and tracked and filtered sky exposures teases out details in the comet’s tail not visible to the unaided eye. Faint structures extend to the top of the frame, over 20 degrees from the comet’s bright coma. Pushed out by the pressure of sunlight itself, the broad curve of the comet’s yellowish dust tail is easy to see by eye. But the fainter, more bluish tail is separate from the reflective comet dust. The fainter tail is an ion tail, formed as ions from the cometary coma are dragged outward by magnetic fields in the solar wind and fluoresce in the sunlight. Outbound NEOWISE is climbing higher in northern evening skies, coming closest to Earth on July 23rd. via wordpress

Wikipedia article of the day for July 16, 2020

Wikipedia article of the day is K-25. Check it out: Summary: K-25 was the Manhattan Project codename for the program that produced enriched uranium for atomic bombs using the gaseous diffusion method at the Clinton Engineer Works in Oak Ridge, Tennessee, in the United States. When the production facility was built in 1944, the four-story gaseous diffusion plant (pictured) was the world’s largest building, with over 152,000 square metres (1,640,000ย sqย ft) of floor space. At the height of construction, over 25,000 workers were employed on the site. Slightly enriched uranium from the S-50 thermal diffusion plant in the form of the highly corrosive uranium hexafluoride was fed into the K-25 gaseous diffusion plant; its product in turn was fed into the Y-12 electromagnetic plant. The enriched uranium was used in the Little Boy atomic bomb used in the atomic bombing of Hiroshima. Production of enriched uranium ended in 1964, gaseous diffusion ceased in 1985, and demolition of the facility was completed in 2017. (Thisย article is part of a featured topic: History of the Manhattan Project.)