SUNSET: 
This Week's Sky at a Glance, January 27 – February 5
Comet ZTF is at its best this week — but every night moonlight encroaches on the scene until a later and later hour. Along the way, the Moon occults Mars for the southern U.S. and again forms isosceles triangles with naked-eyestars.
Tiny Asteroid 2023 BU to Miss Earth
A recently discovered asteroid will pass exceptionally close to Earth on January 26th. Here's how to see it. Also, Comet ZTF (C/2022 E3) is brightening nicely, with three tails visible in binos.
New Observations Reveal Galaxies Near and Far
Astronomers at this month's big winter conference explored intriguing small galaxies at various points in cosmic history.
Hubble and Webb Image Galaxies’ Lost Stars
Deep images of galaxy clusters reveals the light of wandering stars. What set these stars free from their hosts?
JWST Investigates an Exoplanet "Corgi"
The James Webb Space Telescope has found the tiny tail of a close-in exoplanet that's losing its atmosphere.
Light Pollution Is Increasing Even Faster Than We Realized
The average brightness of the night sky is increasing by 10% every year, making the stars less visible.
This Week's Sky at a Glance, January 20 – 29
Venus and Saturn have a close conjunction in twilight. Comet ZTF heads into its best week. And Betelgeuse overtakes Sirius ever earlier in the night.
See a Giant Sunspot!
If you have a solar filter, check out the sunspot group AR 3190 that's crossing the solar disk this week.
Moons of the Solar System
Not so long ago, astronomers thought only a few dozen moons orbited the planets of our solar system. Today, the total count tops 400!
Amateur Astronomers Find Glowing Gas Arc Near Andromeda
An arc that glows green thanks to doubly ionized oxygen appears near the Andromeda Galaxy in a photo obtained by amateur astronomers.
Familiar Fluffy Triangulum Galaxy Has Hidden, Two-Armed Pattern
Astronomers have discovered that one of the Milky Way’s nearest galactic neighbors has dramatically changed its looks in the recent past.
Webb Telescope Confirms Earth-size Exoplanet, Tries to Sniff Its Air
The James Webb Space Telescope has confirmed its first exoplanet, a rocky Earth-size planet, and attempted to take the measure of its atmosphere.
White Dwarf Survived 850-year-old Supernova
A supernova that skywatchers in the Far East observed almost 850 years ago has produced the most unusual remnant astronomers have ever found
This Week's Sky at a Glance, January 13 – 21
Saturn starts the week well above bright Venus in twilight. Watch them close in on each other toward their conjunction on the 22nd. Jupiter and fading Mars shine high. Sirius sparkles below Orion, and binocular Comet ZTF enters its best three weeks.
Astronomers Spot A Tiny Binary System
A tiny binary system is not only small but also ancient, billions of years older than other such systems, which raises questions about its origins.
A 3D Magnetic Map of the Local Bubble
Astronomers have mapped the magnetic field along the "bubble" of gas 1,000 light-years wide around the Sun.
Astronomers Discover Giant Blinking Star
A red giant star thousands of light-years away "blinked," dimming significantly for seven long years, before returning to normal.
Meet Mirfak, the Supergiant of Perseus
Mirfak, the brightest star in the constellation Perseus, is a yellow supergiant star with an uncertain fate.
The James Webb Space Telescope Is Finding Too Many Early Galaxies
Images and spectra from the James Webb Space Telescope suggest that the first galaxies in the universe are too many or too bright compared to what astronomers expected.
Solar and Lunar Eclipses in 2023
Although no total lunar eclipses occur this year, skywatchers can look forward to two “central” solar eclipses — including an annular event in October whose path runs from Oregon through Texas.
