Astronomy

December offers some of the richest meteor showers of the year, highlighted by the reliable Geminids and the more modest Ursids. Unlike sporadic meteors, these showers result fr...

As of today, no major planet in our solar system is in retrograde motion relative to Earth. Mercury, Venus, Mars, Jupiter, and Saturn are currently direct (eastward against the...

Sunset with the moon pairs two reliable celestial events into a quiet, repeatable experience you can plan around the world. Unlike one-off eclipses or rare conjunctions, this pa...

The full moon of March 2019 occurred on Sunday, March 24, at 11:43 UTC (6:43 a.m. EDT). At that moment the Moon was opposite the Sun in ecliptic longitude, fully illuminated as...

In early November the evening sky often shows a waxing crescent or quarter moon in the western sky after sunset, while by late November the brighter gibbous and full moon rise e...

If you are wondering about the Moon, Venus, and Jupiter tonight, this guide explains how to determine visibility for your specific location and time. Planetary visibility depend...

The Leonid meteor shower peaks around November 17 to 18 each year, with activity typically rising a few nights before and after the peak. It is best seen after midnight local ti...

The smiley face moon appears when craters and lunar features create a curved smile and dots for eyes in our perception. This effect is a form of pareidolia, where the brain reco...

A so-called drunk star is not a formal astrophysical category but a descriptive way to refer to a star whose observed motion appears notably irregular, directionally confused, o...

We see the Moon phases because the Moon orbits Earth while Earth orbits the Sun, and only the side of the Moon lit by the Sun is bright enough for us to see from our viewpoint....

Venus is the second planet from the Sun and the third-brightest natural object in Earth’s sky after the Sun and Moon. It appears as the brightest planet and is often called th...

The star that appears closest to the Moon tonight is not fixed, because the Moon moves about 12 degrees east relative to the stars each day and completes an orbit roughly every...

The Geminid meteor shower stands out for its consistency, strong peak rates, and bright, slow-moving meteors. Unlike many showers affected by moonlight or weather variability, t...

Stars without makeup means seeing stars as they are: distant suns revealed only by their light reaching Earth unaided. This guide explains when and how stars become visible to t...

Tonight’s Leonid meteor shower activity depends on timing, sky conditions, and light pollution. The Leonids are an annual shower produced by debris from comet 55P/Tempel–Tut...

The next total lunar eclipse visible from the United States occurs on Wednesday, March 14, 2025. It is the first of two total lunar eclipses in 2025, with a second total eclipse...

The Blood Wolf Moon on January 20–21, 2019, was a total lunar eclipse that coincided with a supermoon and the full wolf moon, creating a reddish appearance visible from much o...

The Moon rises in the east, climbs highest near your local meridian, and sets in the west over the course of a night. Tonight its position depends on your timezone, latitude, an...

The star that appears nearest the Moon tonight depends on the date, time, and your location, because the Moon moves about 12 degrees eastward against the stars each day and the...

You can often see Jupiter and Venus together in the evening or morning sky, but whether they are both visible tonight depends on your time zone, local horizon conditions, and th...

A supermoon occurs when a full moon coincides with or is very close to lunar perigee, the point in the Moon’s orbit nearest to Earth. This alignment makes the Moon appear slig...

An eclipse season is a roughly 34 to 37 day period during which the Sun is close enough to one of the Moon’s nodal points for an eclipse to occur if the geometry aligns. Eclip...

A new moon happens when the Moon sits between Earth and the Sun, with its unilluminated side facing us. From our perspective, the Moon is mostly invisible in the night sky for o...

When the Moon is described as in retrograde, it refers to an apparent westward motion against the background stars as observed from Earth, not a physical reversal of orbit. This...

Jupiter retrograde occurs when the planet appears to move backward in the sky from Earth’s perspective, an apparent shift caused by the relative orbits of Earth and Jupiter. T...

The 2019 vernal equinox was the moment Earth’s rotational axis was tilted neither away from nor toward the Sun, marking the astronomical start of spring in the Northern Hemisp...

The new moon in May 2026 occurs when the Moon aligns closely with the Sun, rendering the lunar disk essentially invisible from Earth. During this phase, the Moon rises and sets...

Cancer is a faint zodiac constellation located between Gemini to the west and Leo to the east. It represents the crab that helped hinder Hercules in Greek mythology and is one o...

The Question Mark Galaxy is an informal name for a distinctive interacting system whose tidal tails and merging components resemble a punctuation mark in long-exposure images. T...

Jupiter is visible tonight from most dark and many suburban skies when it is above the horizon, appearing as a bright, steady silvery star that does not twinkle like a true star...

The new moon occurs when the Moon sits between Earth and the Sun, with its unilluminated side facing us. This phase is invisible to the naked eye in the night sky, yet it plays...

Uranus is technically always above the horizon somewhere on Earth on any given night, but it is usually very difficult to see with the unaided eye. Whether it is visible right n...

The Leonids are an annual meteor shower produced by debris shed by Comet Tempel-Tuttle. Each November, Earth crosses the stream left by the comet, producing meteors that appear...

Galactic donuts are ring-shaped structures found in galaxies and cosmological simulations, influencing star formation and galactic morphology. This guide explains their defining...

The Flower Moon 2018 is a widely used name for the full Moon that falls in May 2018. It follows the tradition of seasonal full Moon names used by many cultures to track months b...

The Strawberry Full Moon is the full moon that falls in June in the Northern Hemisphere. It is named for the short strawberry harvesting season in North America, not for the col...

Venus is the brightest planet in our sky and appears near the Sun, so it rises and sets with the Sun. When it is east of the Sun, it appears after sunset; when it is west of the...

The Flower Moon is the full moon that typically occurs in May. It is one of the traditional names for full moons tied to months, rooted in Native American, Colonial American, an...

A blue moon is the name for a second full moon occurring within the same calendar month or the third full moon in a season that normally has four. It is not a visual color but a...

A meteor shower on December 14 typically refers to the ongoing activity of a named shower that peaks near this date. During the peak, observers may see multiple meteors per hour...

The winter solstice is the moment when one of Earth’s poles reaches its maximum tilt away from the Sun, resulting in the shortest day and longest night of the year. For the he...

Meteor showers occur when Earth passes through streams of debris left by comets or asteroids, producing predictable increases in shooting stars. The 2023 sky offers several reli...

Think of the night sky as a great dome overhead, with stars fixed to its inside surface. A star chart is a two-dimensional map of that dome, projected so you can compare it to w...

A blue moon is the name given to a second full moon that occurs within the same calendar month. This event is predictable using the Gregorian calendar and does not refer to a li...

The full moon occurs when the Moon is opposite the Sun in ecliptic longitude, fully illuminating its Earth-facing side. In February 2026, this lunar phase carries long-standing...

The Strawberry Moon is the traditional name for the full Moon that falls closest to the summer solstice in the Northern Hemisphere. It usually appears in June, though in some ye...

The Leonid meteor shower is an annual event caused by Earth passing through the dust trail of Comet Tempel-Tuttle. When these particles enter the atmosphere at tens of kilometer...

The next full moon in May occurs on a specific date determined by the Moon's orbit, typically around mid-May, though the exact day shifts slightly each year due to the lunar mon...

In astronomy, retrograde describes the apparent backward motion of a planet or celestial body as observed from Earth. This is not a change in the body’s orbit but an optical e...

The Draconids are a reliable annual meteor shower produced by debris from Comet 21P/Giacobini–Zinner. Unlike many showers, the Draconids peak in the evening rather than after...

The April 25 smiley face in the sky refers to a recognizable pattern of celestial objects visible around April 25, often resembling a smiling face. This pattern is not a formal...

This guide profiles notable stars whose names begin with the letter C, focusing on clarity, context, and what observers can expect. Rather than a simple list, we explain how mod...

The Lyrids are a reliable annual meteor shower produced by Earth passing through the dusty debris trail of comet C/1861 G1 Thatcher. In 2025, the shower peaks around mid‑April...

The 9-1-1 meteor shower is a modest, periodic shower of likely sporadic or minor origin that can appear near the date range around September 1 to early October, with a radiant l...

Trappist‑1 is an ultracool dwarf star about 40 light‑years away in the constellation Aquarius that hosts a system of seven rocky planets, three to four of which orbit within...

Trappist‑1 is an ultracool dwarf star located about 40 light‑years away in the constellation Aquarius, known for hosting a rich family of seven confirmed rocky planets. Disc...

The Trappist system refers to two installations: TRAPPIST, a robotic telescope at La Silla Observatory, and TRAPPIST-South, an exoplanet and comet watcher in the Southern Hemisp...

After new moon twilight, the sky darkens fully, and the first slim lunar crescent becomes visible in the west after sunset. New moon occurs when the Moon is between Earth and th...

Stars that start with R span well-known objects such as Rigel, Regulus, and Rasalhague, alongside red dwarfs and variable stars whose designations begin with this letter. This g...

Trappist-1 is an ultracool dwarf star located about 40 light-years away in the constellation Aquarius, orbited by seven rocky planets discovered between 2015 and 2017. Three of...

The Trappist solar system refers to the exoplanetary system around the ultracool dwarf star TRAPPIST-1, located about 40 light-years away in the constellation Aquarius. It is be...

A globular cluster is a densely packed, roughly spherical group of hundreds of thousands to millions of stars that are gravitationally bound. These older stellar systems orbit g...

Trappist-1e is a rocky exoplanet just larger than Earth, orbiting within the conservative habitable zone of the ultracool dwarf star TRAPPIST-1, approximately 40 light-years awa...

The Flower Moon is the traditional name for the full moon that occurs in May in many Northern Hemisphere calendars. It is one of the monthly full-moon names rooted in seasonal c...

The Lyrids are one of the oldest recorded meteor showers, with activity typically spanning late April. The main Lyrid meteor shower dates each year fall between about April 16 a...

The phrase Wednesday star most often describes a distinct star (or sometimes a small asterism) that appears near the waning crescent Moon in the early dawn sky on or around Wedn...

The astronomer scandal emerged when a prominent professional astronomer was found guilty of research misconduct, including data fabrication, duplicate publication, and improperl...

Trappist-1 is an ultracool dwarf star just 40 light-years away whose seven transiting planets are among the most thoroughly studied worlds beyond the Solar System. Discovered be...

The Lyrids are a reliable annual shower produced by dust from Comet Thatcher (C/1861 G1). In 2026, the shower’s peak falls near a waning crescent Moon, reducing moonlight inte...

Trappist-1 is an ultracool dwarf star , specifically a very late M-type main-sequence star with a cool surface temperature around 2,516 Kelvin, roughly 40 light-years away in th...