EarthSky

Look for Cassiopeia and the Big Dipper

Watch the celestial clock and its 2 great big hour hands – Cassiopeia and the Big Dipper – as they swing around the North Star every night!

A graphic showing global average temperatures from 1850 to 1919.

2010 to 2019 was the hottest decade on record

According to the UK’s Met Office, each decade from the 1980s has been successively warmer than all the decades that came before. 2019 concludes the warmest ‘cardinal’ decade (those spanning years ending 0-9) in records that stretch back to the mid-19th century.

An image of Betelgeuse taken at sub-millimeter wavelengths taken by the Atacama Large Millimeter/submillimeter Array (ALMA).

How far is Betelgeuse?

Recent speculation that Betelgeuse might be on the verge of going supernova prompted many to ask: how far away is it? But getting a distance measurement for this star has been no easy task.

Bright moon in front of Winter Circle loop of stars.

Identify stars in the Winter Circle

Go outside, and look for the waxing gibbous moon tonight. Then notice the stars nearby. Tonight’s moon is within the Winter Circle stars.

Contemplate the apex of the sun’s way

Our sun moves around the center of the galaxy, toward the star Vega. Astronomers call this motion the apex of the sun’s way. One circuit – about 230 million years – is called a cosmic year.

This satellite image was collected by NOAA-NASA's Suomi NPP satellite using the VIIRS (Visible Infrared Imaging Radiometer Suite) instrument on Jan. 01, 2020. Actively burning fires, detected by thermal bands, are shown as red points. Lynn Jenner with information from New South Wales Rural Fire website and the Bushfires and Natural Hazards CRC website. Via NASA Worldview, Earth Observing System Data and Information System (EOSDIS).

Ferocious fires in Australia intensified this week

The outlook for the bushfire situation in Australia continues to be grim. This post is an update via NASA, containing NOAA-NASA satellite images of actively burning fires and the resultant billowing smoke.

January’s birthstone is the garnet

Happy birthday, January babies!  Your birthstone is the garnet.

Top 10 tips for meteor-watchers

How to watch a meteor shower. Tips for beginners.

A crowded starfield located toward the center of our Milky Way galaxy.

An ancient starburst in the Milky Way’s center

New observations reveal that – about a billion years ago – the center of our Milky Way galaxy underwent a period of intense star formation, resulting in over 100,000 supernovae.

Wavelike clouds at twilight, above a mountain landscape.

Clouds that look like ocean waves

They’re called Kelvin-Helmholtz clouds, aka billow clouds or shear-gravity clouds, and they look like breaking ocean waves.