Articles About Astronomy (139)
![Illustration image](https://c.tadst.com/gfx/150x84/four-seasons.jpg?1)
Defining Seasons
When do seasons begin and end in the two hemispheres?
![Illustration image](https://c.tadst.com/gfx/150x84/twilight-dubai.jpg?1)
Twilight, dawn, & dusk
Learn more about different kinds of twilight, dawn and dusk.
![Inquisitive Palomino horse with a white blaze standing in a field at sunset. The mountains and sky glow red from the setting sun.](https://c.tadst.com/gfx/150x84/horse-mountains-full-moon.jpg?1)
Full Moon Names
Ancient cultures gave names to the Full Moon. These names are still in use today.
![Zoomed in image of the Full Moon with its surface of craters and mountains.](https://c.tadst.com/gfx/150x84/full-moon-phase2.jpg?1)
The Full Moon
The third primary phase of the Moon is the Full Moon.
![Illustration image](https://c.tadst.com/gfx/150x84/total-lunareclipse1.jpg?1)
What's a Blood Moon?
A total lunar eclipse is often called a Blood Moon because of the red glow the eclipsed Moon gets. The term is also used for four total lunar eclipses that occur in a row.
![Illustration of night sky with stars and a crescent moon.](https://c.tadst.com/gfx/150x84/promo-card-calendar.png?1)
Astronomical Events 2024
When, where, and how to see things happening in the sky and space.
![Full Moon rising behind a line of dark trees.](https://c.tadst.com/gfx/150x84/supermoon-rise.jpg?1)
What Is a Supermoon?
When the Full Moon or occurs near the Moon's closest approach to Earth, its perigee, it is often called a supermoon.
![December solstice illustration December solstice illustration](https://c.tadst.com/gfx/150x84/december-solstice-dark.png?1)
December Solstice
December solstice marks the shortest day north of the equator and the longest day in the south.
![Frozen lake and snowy forest](https://c.tadst.com/gfx/150x84/winter-lake.jpg?1)
When Does Winter Start?
The first day of winter in the Northern Hemisphere is in December; south of the equator, it is in June. Find out exactly when the winter season starts.
![New Moon Phase Illustration of the Moon's position in space in relation to Earth and the Sun at New Moon.](https://c.tadst.com/gfx/150x84/new-moon-phase.png?1)
The New Moon
When is the next New Moon? New Moon is when the Sun and Moon are aligned, with the Sun and Earth on opposite sides of the Moon.
![A tree changing through the four seasons. A tree changing through the four seasons.](https://c.tadst.com/gfx/150x84/four-seasons-causes.jpg?1)
What Causes Seasons on Earth?
Seasons change because Earth's rotational axis tilts away or towards the Sun during the course of a year.
![September equinox illustration illustration of Earth's position in relation to the Sun's rays at the September equinox](https://c.tadst.com/gfx/150x84/september-equinox-dark.png?1)
September Equinox
The Sun shines directly on the Equator on the September equinox and the length of day and night is nearly equal, but not quite.
![Full Moon peeking through branches. Blue and foggy background.](https://c.tadst.com/gfx/150x84/full-moon-peeking-tree-branches-fog.jpg?1)
What Is a Blue Moon?
“Once in a blue moon” suggests something is very rare. But just how rare is a Blue Moon?
![June solstice illustration Earth's position in relation to the Sun's rays at the June solstice.](https://c.tadst.com/gfx/150x84/june-solstice-dark.png?1)
June Solstice 2024
The June solstice is the longest day of the year in the Northern Hemisphere and the shortest day in the Southern Hemisphere.
![2 kids watching seagulls at low tide on a beach](https://c.tadst.com/gfx/150x84/istock-512273677.jpg?1)
What Causes Tides?
The gravitational pull of the Moon and the Sun makes the water in the oceans bulge, causing a continuous change between high and low tide.
![Illustration image](https://c.tadst.com/gfx/150x84/golden-hour-retriever.jpg?1)
The Golden Hour – When Sunlight Turns Magical
When the Sun is close to the horizon, its light appears warmer and softer. Explore the definition of the golden hour, along with helpful photography tips.
![Eclipse History](https://c.tadst.com/gfx/150x84/eclipse-traditions.jpg?1)
Solar and Lunar Eclipses
Solar and lunar eclipses, why they occur, when the next eclipse is, and from where you can see them.
![Illustration image](https://c.tadst.com/gfx/150x84/compass-navigation.jpg?1)
Magnetic Declination
A compass needle doesn't point to the geographical North Pole but to magnetic north. Did you know that it usually doesn't point to the magnetic North Pole either?
![March equinox illustration March equinox illustration](https://c.tadst.com/gfx/150x84/march-equinox-dark.png?1)
March Equinox
At the March equinox, the Sun crosses the equator from south to north. Explanation and 2025 equinox date.
![Illustration image](https://c.tadst.com/gfx/150x84/chicago-twilight.jpg?1)
Civil Twilight – Civil Dawn & Dusk
Civil twilight is the brightest of the twilight phases. How is it defined and when does it start and end? What are civil dawn and civil dusk?
![Underside of an airplane visible in front of a half Moon during the day with a blue sky in the background.](https://c.tadst.com/gfx/150x84/plane-front-of-half-moon.jpg?1)
First Quarter Moon
The 1st Quarter Moon is a primary Moon phase when we can see exactly half of the Moon's surface lit up. Which half depends on where you are on Earth.
![Illustration image](https://c.tadst.com/gfx/150x84/autumn-lake.jpg?1)
When Does Fall Start?
North of the equator, fall begins in September. Find out the exact dates for both hemispheres.
![A total solar eclipse, as seen from San José de Jáchal, Argentina, July 2019.](https://c.tadst.com/gfx/150x84/totality-corona.jpg?1)
Total Solar Eclipse
Total solar eclipses occur when the New Moon comes between the Sun and Earth and casts the darkest part of its shadow, the umbra, on Earth.
![A Waxing Gibbous Moon against a black sky. A Waxing Gibbous Moon against a black sky.](https://c.tadst.com/gfx/150x84/waxing-gibbous-moon.jpg?1)
Waxing Gibbous Moon
The Waxing Gibbous Moon is an intermediate Moon phase that starts after the First Quarter Moon and lasts until the Full Moon.
![Illustration image](https://c.tadst.com/gfx/150x84/aurora.jpg?1)
Northern and Southern Lights
What causes these colorful and dramatic light displays in the sky, and when and from where can you see them?
![Looking up at the Sun framed by buildings.](https://c.tadst.com/gfx/150x84/city-sun.jpg?1)
What Is Solar Noon?
Noon is at 12 o'clock but solar noon can be at a different time. What's the difference between the two?
![Illustration image](https://c.tadst.com/gfx/150x84/nautical-twilight-lake.jpg?1)
Nautical Twilight – Nautical Dawn & Dusk
Nautical twilight is the second twilight phase. How is it defined and when does it start and end? What are nautical dawn and nautical dusk?
![Illustrative comparison of a Supermoon and Micromoon.](https://c.tadst.com/gfx/150x84/supermoon-micromoon.png?1)
What Is Lunar Perigee and Apogee?
The Moon's orbit around Earth is elliptical. The point of the orbit closest to Earth is called perigee, while the point farthest from Earth is known as apogee.
![A Last Quarter Moon is sometimes called a Half Moon. A Last Quarter Moon, also called Half Moon, where the left half of the Moon is lit up.](https://c.tadst.com/gfx/150x84/third-quarter-moon-half.jpg?1)
Third Quarter Moon
The Third or Last Quarter Moon is when the opposite half of the Moon is illuminated compared to the First Quarter.
![Red, eclipsed moon during total lunar eclipse on the dark sky with stars, partially covered by tree branches.](https://c.tadst.com/gfx/150x84/og-image-total-lunar-eclipse.png?1)
Total Lunar Eclipse
What happens when the Earth’s dark, reddish shadow covers the Moon completely?
![Spring: Flowering fruit tree in garden](https://c.tadst.com/gfx/150x84/spring-blossom.jpg?1)
When Does Spring Start?
The first day of spring is at the vernal equinox, when day and night are equal. Find out the exact time and date.
![An image of the Sun in the sky](https://c.tadst.com/gfx/150x84/sun-sky.jpg?1)
Equation of Time
The difference between the time measured by the Sun and the time measured by our clocks is known as the equation of time.
![Illustration image](https://c.tadst.com/gfx/150x84/nashville-twilight.jpg?1)
Astronomical Twilight – Astronomical Dawn & Dusk
Astronomical twilight is the darkest of the twilight phases. How is it defined and when does it start and end? What are astronomical dawn and astronomical dusk?
![Illustration image](https://c.tadst.com/gfx/150x84/waning-gibbous-moon.jpg?1)
Waning Gibbous Moon
An intermediate Moon phase that starts after the Full Moon and lasts until half of the Moon's face remains lit up at the Third Quarter Moon.
![Sun peeking through trees with snow on the leaves and branches and snow on the ground.](https://c.tadst.com/gfx/150x84/december-solstice-winter.jpg?1)
10 Facts about the December Solstice
Here are 10 things about the December solstice you might not know.
![Illustration of a partial, annular, and a total solar eclipse.](https://c.tadst.com/gfx/150x84/types-of-solar-eclipses.png?1)
What Is a Solar Eclipse?
Solar eclipses happen when the Moon moves between Sun and Earth, blocking the Sun's rays and casting a shadow on Earth.
![Diagram showing the distance between the Sun and Earth at different times of the year (perihelion and aphelion).](https://c.tadst.com/gfx/150x84/sun-distances-card.png?1)
Earth's Perihelion
Earth's closest approach to the Sun is two weeks after the December solstice is a coincidence and has no special significance.
![Sun setting in the background with cloudy sky and trees in the foreground.](https://c.tadst.com/gfx/150x84/sunset-in-valley.jpg?1)
Equinox: Equal Day & Night?
Equinoxes don't have exactly 12 hours of day and night all over the world, like many believe. Such days, called equilux, do occur, but depend on your location.
![Image of Full Moon red in color due to refraction with dark sky in the background.](https://c.tadst.com/gfx/150x84/red-full-moon.jpg?1)
Lunar Eclipse: Red Moon
Find out why a totally eclipsed Moon turns a shade of red.
![Vector illustration of thick book and a pencil](https://c.tadst.com/gfx/150x84/astronomical-glossary.png?1)
Astronomical Glossary - Terms & Definitions
What do astronomers really mean when they use those technical terms?
![Illustration image](https://c.tadst.com/gfx/150x84/waxing-crescent-moon.jpg?1)
Waxing Crescent Moon
The Waxing Crescent Moon phase starts after New Moon and lasts until half of the Waxing Moon's surface is illuminated at First Quarter Moon.
![Hindu God Rahu, known for swallowing the sun and causing eclipses. The Hindu deity Rahu.](https://c.tadst.com/gfx/150x84/hindu-god-rahu.jpg?1)
Solar Eclipse Myths
The solar eclipse has inspired many mythical stories and influenced human behavior. Even today, eclipses of the Sun are considered bad omens in many cultures.
![Full Moon and branches against a dark sky.](https://c.tadst.com/gfx/150x84/micromoon.jpg?1)
What Is a Micromoon?
A Micromoon is the name given to a Full or New Moon when the Moon is farthest from Earth.
![Radio telescopes of the Very Large Array in New Mexico, USA.](https://c.tadst.com/gfx/150x84/very-large-array.jpg?1)
What Is Universal Time?
Universal Time is a solar time standard used in astronomy and to define time on Earth. How is it measured? What's the difference between UT, UT0, UT1, UT2, and UTC?
![Star trails over an observatory. Star trails over an observatory.](https://c.tadst.com/gfx/150x84/star-trails-length-day.jpg?1)
How Long Is a Day on Earth?
In terms of solar time, most days are a little longer than 24 hours. Exact day length for today and yesterday.
![Illustration showing Earth's axis drawn as a red line.](https://c.tadst.com/gfx/150x84/axial-tilt.png?1)
Earth Is Tilted
When an object the size of Mars crashed into the newly formed planet Earth around 4.5 billion years ago, it knocked it over and left it tilted at an angle.
![Dark New Moon night with the star filled sky in the background and fir trees in the foreground.](https://c.tadst.com/gfx/150x84/starry-night-sky-forest.jpg?1)
What Is a Black Moon?
A Black Moon can be the third New Moon in a season with four New Moons or the second New Moon in the same calendar month, or even no New Moon at all.
![Illustration image](https://c.tadst.com/gfx/150x84/summer-dog.jpg?1)
When Does Summer Start?
When is the summer solstice 2024 in the southern and northern hemispheres?
![Black background with rays extending out from a circle and a bright light from the top of the circle.](https://c.tadst.com/gfx/150x84/totality-great-american-total-solar-eclipse.jpg?1)
How Often Do Solar Eclipses Happen?
There are between 2 and 5 solar eclipses every year, each one visible only in a limited area.
![A close-up of the thin sliver of a yellow waning crescent moon.](https://c.tadst.com/gfx/150x84/waning-crescent-moon-yellow.jpg?1)
Waning Crescent Moon
During the Waning Crescent Moon phase, the lit-up part of the Waning Moon shrinks from the Third Quarter Moon until it disappears from view at New Moon.
![A sundial with the Sun casting a shadow. A sundial with the Sun casting a shadow.](https://c.tadst.com/gfx/150x84/sundial-local-mean-time.jpg?1)
What Is Local Mean Time?
Use a sundial to determine the time of day and you will probably be off by a few minutes. That's where LMT comes into play. How is it measured and what is it used for?
![Dark blue sky in the background with a glowing ring around the Sun. The center of the sun is dark.](https://c.tadst.com/gfx/150x84/annular-eclipse-new-mexico-2012.jpg?1)
Annular Solar Eclipse
An annular solar eclipse is when the Moon moves in front of the Sun but leaves the outer edge of the Sun visible as a ring of fire.
![Image of a waterfall at night with one bright moon bow and a faint moon bow above it. Dark skies and city lights in the background.](https://c.tadst.com/gfx/150x84/double-moonbow-over-yosemite.jpg?1)
What Are Moonbows?
Moonbows occur when the Moon’s light is reflected and refracted off water droplets in the air.
![Illustration image](https://c.tadst.com/gfx/150x84/total-solar-eclipse-com.png?1)
What Is the Umbra?
The umbra is the dark center portion of a shadow. The Moon's umbra causes total solar eclipses, and the Earth's umbra is involved in total and partial lunar eclipses.
![Meteor showers are easy to view. All you need is some patience, a dark viewing spot, and our Interactive Meteor Shower Sky Map. A man's silhouette with the milky way and a meteor in the backdrop.](https://c.tadst.com/gfx/150x84/viewing-meteor-shower.jpg?1)
Meteors: How to See
Tips on how and where to see shooting stars.
![Illustration image](https://c.tadst.com/gfx/150x84/dusk-kyoto.jpg?1)
What Is Dusk?
Dusk generally refers to the transition from day to night. However, the scientific definition is more specific and consists of three stages of dusk.
![Image of a faint eclipsed Moon behind a brightly it castle.](https://c.tadst.com/gfx/150x84/lunar-eclipse-siena.jpg?1)
Watching Lunar Eclipses
A lunar eclipse can be seen with the naked eye, unlike solar eclipses, which have special safety requirements.
![Picture with fields in the foreground and a crescent shaped Sun with Moon in front of it. Cloudy skies in the background.](https://c.tadst.com/gfx/150x84/partial-solar-eclipse-arkansas.jpg?1)
Partial Solar Eclipse
A partial solar eclipse happens when the Moon only partially covers the Sun.
![Illustration image](https://c.tadst.com/gfx/150x84/santorini-dawn.jpg?1)
What Is Dawn?
Dawn generally refers to the transition from night to day. However, the scientific definition refers to three separate and definable stages of dawn.
![Illustration of altitude and azimuth in the celestial sphere.](https://c.tadst.com/gfx/150x84/horizontal-coordinate-system.png?1)
Altitude & Azimuth: The Horizontal Coordinate System
Learn how to use altitude (elevation) and azimuth angles to locate any object in the sky, such as stars, planets, satellites, the Sun, or the Moon.
![A pathway in a park during fall (autumn). A pathway in a park during fall (autumn).](https://c.tadst.com/gfx/150x84/september-equinox-facts.jpg?1)
10 Facts about the September Equinox
10 things you may not know about the September equinox.
![Illustration image](https://c.tadst.com/gfx/150x84/tell-time-with-stars.png?1)
Timekeeping by Stars
Out and about at night without a watch or a smartphone readily available? If you are in the Northern Hemisphere use the Big Dipper and the North Star to tell the time.
![Partial lunar eclipse on the dark, starry night with Earth's shadow marked on the sky.](https://c.tadst.com/gfx/150x84/shadows-lunar-eclipses.png?1)
Shadow Science
There are three kinds of shadows that produce eclipses.
![The full moon can look larger on the horizon than when higher up in the sky. Full moon on the horizon at the end of a dock.](https://c.tadst.com/gfx/150x84/moon-illusion.jpg?1)
The Moon Illusion
Some days, the Full Moon at the horizon looks larger than a normal Full Moon. Does the Moon really change size or is this an illusion?
![Illustration showing all the different Moon phases next to one another](https://c.tadst.com/gfx/150x84/moon-phases-together.jpg?1)
What Is a Lunar Month?
A lunar month is the time it takes the Moon to pass through all of the Moon phases, usually measured from a New Moon the next New Moon.
![Illustration image](https://c.tadst.com/gfx/150x84/asteroid-10-things.jpg?1)
What Are Asteroids?
Learn more about these space rocks orbiting the Sun.
![Eclipse History](https://c.tadst.com/gfx/150x84/eclipse-traditions1.jpg?1)
Solar Eclipses in History
Solar eclipses were historically seen as omens that bring about death and destruction. People in many ancient civilizations tried their best to understand them.
![The village of Mararola, Italy, during the blue hour.](https://c.tadst.com/gfx/150x84/blue-hour-cinque-terre.jpg?1)
The Blue Hour
The blue hour in the morning and evening is a favorite with photographers. When does it start & end? Explanation with times, degrees & photography tips.
![Illustration image](https://c.tadst.com/gfx/150x84/sunhalo.jpg?1)
Halos, Sundogs and Light Pillars
These are atmospheric phenomena created by the reflection and refraction of light by ice crystals in the atmosphere.
![Illustration of partial lunar eclipse](https://c.tadst.com/gfx/150x84/og-image-partial-lunar-eclipse.png?1)
Partial Lunar Eclipse
What happens when the Earth’s dark shadow covers part of the Moon’s face?
![Lunar Eclipse Penumbral Penumbral lunar eclipse illustration with positions of Sun, Earth, and Moon in space](https://c.tadst.com/gfx/150x84/totallunareclipsepenumbral.png?1)
What Is the Penumbra?
The penumbra is the lighter outer part of a shadow. The Moon's penumbra causes partial solar eclipses, and the Earth's penumbra is involved in penumbral lunar eclipses.
![Illustration image](https://c.tadst.com/gfx/150x84/mercury-transit.png?1)
Mercury Transit
When Mercury transits the Sun, you can see it as a tiny black dot silhouetted against the Sun's disk.
![Illustration image](https://c.tadst.com/gfx/150x84/measuring-sky-with-hand.png?1)
How to measure the sky
Measure the sky and find out distances between celestial objects using your hands and fingers.
![Photo of people on a cliff looking at the midnight Sun in Nordkapp, Norway.](https://c.tadst.com/gfx/150x84/midnight-sun.jpg?1)
Midnight Sun
The Midnight Sun is where the Sun never sets over a period of 24 hours or more. It occurs in polar regions during summer.
![Sun peeking through trees with snow on the leaves and branches and snow on the ground.](https://c.tadst.com/gfx/150x84/december-solstice-winter.jpg?1)
December Solstice Customs
Learn more about the customs, traditions and events surrounding the December solstice.
![Nordlys over en nordnorsk fjord i mørketiden. Nordlys over en nordnorsk fjord i mørketiden.](https://c.tadst.com/gfx/150x84/nordlys-morketid.jpg?1)
What Are Polar Nights?
A Polar Night is a night that lasts for at least 24 hours. It's the opposite of Midnight Sun / Polar Day.
![Vector illustration of a pin.](https://c.tadst.com/gfx/150x84/og-pinhole-projector.png?1)
Make a Pinhole Projector
Make a simple pinhole projector using 2 pieces of card or paper to safely watch a projection of a solar eclipse.
![Illustration of a comet](https://c.tadst.com/gfx/150x84/comet-illustration.jpg?1)
What Are Comets?
Icy leftovers from the birth of the solar system.
![Annular solar eclipse illustration with positions of Earth, Moon, and Sun in space](https://c.tadst.com/gfx/150x84/annular-solar-eclipse.png?1)
What Is the Antumbra?
The antumbra is the lighter part of a shadow that forms at a certain distance from the object casting the shadow. It is involved in annular solar eclipses and planet transits.
![Illustration image](https://c.tadst.com/gfx/150x84/tropical-year-illustration.png?1)
A Year Is Never 365 Days
A tropical year, also known as a solar year, is the time it takes for the seasons to repeat, approximately 365.242189 days.
![Vector illustration of eclipsed moon during penumbral eclipse.](https://c.tadst.com/gfx/150x84/og-penumbral-lunar-eclipse.png?1)
Penumbral Lunar Eclipse
What happens when the Earth’s lighter, outer shadow covers the Moon?
![Parents playing with their young daughter in the evening sun](https://c.tadst.com/gfx/150x84/evening-family.jpg?1)
10 Facts about the June Solstice
10 things you may not know about the June solstice.
![Position of Sun, Moon, and Earth during a hybrid solar eclipse.](https://c.tadst.com/gfx/150x84/hybrid-solar-eclipse.png?1)
Hybrid Solar Eclipse
A hybrid solar eclipse or annular/total eclipse starts as a total solar eclipse but changes into an annular solar eclipse. Why is that so? When is the next hybrid eclipse?
![Illustration of a solar analemma figure-of-eight above a city skyline](https://c.tadst.com/gfx/150x84/solar-analemma-ill.jpg?1)
Solar Analemma
A Solar Analemma is a graph showing the position of the Sun in the sky above a single location at the same time of the day throughout the course of a year.
![An illustration of the Sun and blue light scattering through the atmosphere to a figure of a woman on Earth and a text explaining, "Daytime, blue light scatters easily in the atmosphere. On the left side is a male figure receiving red and orange scattered](https://c.tadst.com/gfx/150x84/rayleigh-scattering-illustration.png?1)
Rayleigh Scattering
Why does the sky turn red during sunrise and sunset?
![Vector illustration of partial solar eclipse and a blue sky.](https://c.tadst.com/gfx/150x84/og-magnitude-of-eclipses.png?1)
Eclipse Magnitude
Learn more about the number that tells us how deep an eclipse will be.
![Vector illustration of blue eclipse glasses.](https://c.tadst.com/gfx/150x84/og-eyes-protection.png?1)
Protect Your Eyes!
Never look directly at the Sun without proper protection.
![Close-up of the far side of the Moon with partial Earth in the background.](https://c.tadst.com/gfx/150x84/far-side-moon-image-nasa.jpg?1)
The Moon's Far Side
Contrary to popular belief, there is no "dark side of the Moon." When there is a New Moon from Earth's perspective, the far side of the Moon is lit up.
![Snowdrops growing up trough the snow.](https://c.tadst.com/gfx/150x84/snowdrops-snow-spring.jpg?1)
10 Facts about the March Equinox
On this date, day and night are of almost equal duration around the world.
![Vector illustration of an open box.](https://c.tadst.com/gfx/150x84/og-box-pinhole-projector.png?1)
Make a Box Pinhole Projector
You’ll need a cardboard box, plus a few other household items.
![Vector illustration of green binoculars.](https://c.tadst.com/gfx/150x84/og-eclipse-projector.png?1)
Make a Solar Eclipse Projector
Make a Sun projector a pair of binoculars or a telescope to safely watch solar eclipses or a planet transit.
![Illustration image](https://c.tadst.com/gfx/150x84/stonehenge-june-solstice.jpg?1)
June Solstice Traditions
In many Northern Hemisphere cultures, the June solstice is associated with holidays, feasts and celebrations.
![Crescent Moon with dark blue sky in the background. The unlit part of the Moon has a dim glow. Bright star shines to the left of the Moon.](https://c.tadst.com/gfx/150x84/earthshine.jpg?1)
What Is Earthshine?
Earthshine is a dull glow that occurs when the Sun’s light reflects off the Earth's surface and illuminates the unlit portion of the Moon.
![Illustration image](https://c.tadst.com/gfx/150x84/venus-transit.jpg?1)
Transit of Venus: June 5-6, 2012
The 2012 Venus transit was the last chance to see this phenomenon for over 100 years. Mercury transits happen more often, the next one in 2032.
![A partially red Moon rising from behind mountains.](https://c.tadst.com/gfx/150x84/blood-moon-mountain.jpg?2)
Lunar Eclipse Photography
Planning to take pictures of a lunar eclipse? Follow our guide for amazing eclipse photos! We tell you what kind of equipment you need and how to use it.
![Two meteor trails against a starry background in the night sky.](https://c.tadst.com/gfx/150x84/meteors.jpg?1)
What Is a Meteor Shower?
Shooting stars produced when Earth travels through debris from a comet or asteroid.
![Starry night sky in the background with desert in the foreground. White truck on the side and a triangular glow of zodiacal lights in the sky.](https://c.tadst.com/gfx/150x84/starry-night-zodiacal-lights-morocco-desert.jpg?1)
Zodiacal Light
Also known as false dawn, zodiacal light is a rare optical phenomena that occur around sunset and sunrise in early spring and late fall.
![Eclipse glasses held up towards a solar eclipse.](https://c.tadst.com/gfx/150x84/iphone-eclipse-photo-2.jpg?1)
Solar Eclipse Photography
Take that perfect solar eclipse photo with your camera and some extra equipment, or capture it with your mobile phone.
![Illustration image](https://c.tadst.com/gfx/150x84/tropical-year-lengths.png?1)
Length of Tropical Years 1900–2100
Exact length down to the second of tropical years ranging from 1900 to 2100. It is also known as a solar year, astronomical year, or equinoctial year.
![Close-up image of the Full Moon.](https://c.tadst.com/gfx/150x84/not-blue-moon.jpg?1)
Is a Blue Moon Blue?
A Blue Moon is a type of a Full Moon. It can also be a rare Moon that looks blue due to atmospheric dust particles.
![Illustration image](https://c.tadst.com/gfx/150x84/lovejoy.jpg?1)
All about Comet Lovejoy
Comet Lovejoy (C/2013 R1) is one of 3 comets that will grace the skies in November, 2013.
![Illustration image](https://c.tadst.com/gfx/150x84/mars-venus-jupiter-27oct.png?1)
Jupiter and Venus Closest Conjunction of 2015
From time to time, some of the planets in our solar system are in conjunction and become visible together in the sky.
![Illustration image](https://c.tadst.com/gfx/150x84/ison.jpg?1)
All about Comet ISON
Everything you need to know about Comet ISON or C/2012 S1.
![Illustration image](https://c.tadst.com/gfx/150x84/asteroid-2004bl86.jpg?1)
Asteroid 2004 BL86 to Fly By Earth
On Monday, January 26, 2015 asteroid 2004 BL86 flew by at only 3 times the distance of the Moon from the Earth.
![Illustration image](https://c.tadst.com/gfx/150x84/comet.jpg?1)
2013: Year of comets
2013 is going to be a good year for comet watchers, with at least 3 comets that may be visible without the aid of sophisticated equipment.
![Baily’s Beads seen from Madras, Oregon during the total solar eclipse of August 2017.](https://c.tadst.com/gfx/150x84/bailys-beads-august-2017.jpg?1)
Sunlight through valleys
Read more about Baily’s beads.
![The diamond ring effect, as seen from San José de Jáchal, Argentina, July 2019.](https://c.tadst.com/gfx/150x84/totality-july-2019.jpg?1)
A jewel in the sky
Read more about the diamond ring.
![timeanddate’s Anne Buckle checks her eclipse glasses ahead of the July 2019 total solar eclipse in San José de Jáchal, Argentina.](https://c.tadst.com/gfx/150x84/eclipse-glasses.jpg?1)
How to Make the Best Use of Solar Eclipse Glasses
Learn the four basic rules for using eclipse glasses to make the most of viewing a solar eclipse while maintaining your eye safety.
![An eclipsed Moon, framed between two buildings](https://c.tadst.com/gfx/150x84/total-lunar-eclipse-framed.jpg?1)
Eclipse Seasons
Roughly speaking, there are two eclipse seasons per year. Each season contains different kinds of eclipses to the last one.
![Map of Partial Lunar Eclipse on November 18–19, 2021](https://c.tadst.com/gfx/150x84/november-1819-lunar-eclipse.jpg?1)
Why Does a Lunar Eclipse Have Two Dates?
The date of a lunar eclipse depends on where you are in the world. At timeanddate, we normally use two numbers to give the date of a lunar eclipse.
![Machu Picchu at sunrise.](https://c.tadst.com/gfx/150x84/machu-picchu.jpg?1)
A Once-In-A-Thousand-Years Eclipse
The partial lunar eclipse on November 19, 2021, was the longest since the 15th century, around the time Machu Picchu was being built.
![Families flying kites from the rooftops of their old brick buildings in the old city of Jaipur. This is a popular sport of Makar Sankranti and Independence Day.](https://c.tadst.com/gfx/150x84/kites-rooftops-sunset.jpg?2)
Holidays Connected to Astronomic Events
People worldwide mark the movement of celestial bodies with a wide variety of celebrations and rituals. We list the most important astronomical holidays.
![An image of the solar system showing the alignment of the Earth, Jupiter, and Saturn for the Great Conjunction of 2020.](https://c.tadst.com/gfx/150x84/great-conjunction-2020.png?1)
What Is a Conjunction?
Two astronomical bodies appear to meet in the sky—but it’s an illusion.
![A sundial casting a shadow.](https://c.tadst.com/gfx/150x84/sun-dial-time-equation.jpg?1)
Equation of Time
Why doesn't the year's earliest sunset occur on the winter solstice, even though it is the shortest day of the year in terms of daylight?
![A view from our Night Sky Map of totality over the US city of Dallas at 13:42 (local time) on April 8, 2024.](https://c.tadst.com/gfx/150x84/dallas-max-eclipse-april-2024.jpg?1)
What Is the Ecliptic?
The ecliptic is the name given to the path the Sun follows through the stars and constellations over the course of a year.
![The Earth in space, as seen by the crew of Apollo 11.](https://c.tadst.com/gfx/150x84/1599earth762.jpg?1)
Equinoxes and Solstices
Equinoxes and solstices are a result of Earth’s tilt and its orbit around the Sun.
![A happy couple running through the waves on a sunlit beach.](https://c.tadst.com/gfx/150x84/sunset-photography.jpg?1)
Sunset and Sunrise Photography
The secrets of how to use your cellphone to take impressive pictures during sunrise and sunset.
![The Moon (just after Full Moon).](https://c.tadst.com/gfx/150x84/503735796.jpg?1)
The Moon: Our Satellite
Our Moon is the 5th-largest of the more than 200 moons in the solar system.
![Silhouette of a woman against a large full Moon in the background.](https://c.tadst.com/gfx/150x84/moon-human.jpg?1)
The Moon Effect
Does the Moon really affect our sleep, behavior, and personality?
![A woman hiker taking a picture of the Crescent Moon over three pointy mountains: Tre Cime in the Dolomites , Italy.](https://c.tadst.com/gfx/150x84/hiker-mountains-picture-moon.jpg?1)
Take a Good Picture of the Moon
You can take great pictures of the Moon with a bit of planning.
![Illustration of Moon Phases](https://c.tadst.com/gfx/150x84/og-moon-phases-new.png?1)
The Moon Phases
The Moon has four primary phases and four intermediate phases during a lunar month. Here's all you need to know about each phase.
![A screenshot from timeanddate's Moon phases video, showing the Moon and Sun moving across the sky](https://c.tadst.com/gfx/150x84/wide-angle.jpg?1)
Seven Ways We Simplified Our Moon Phases Video
Seven of the biggest simplifications we made in our video about Moon phases.
![See 46P/Wirtanen zoom across the sky with the Night Sky Map. Screenshot of the Night Sky Map showing Comet Wirtanen's path.](https://c.tadst.com/gfx/150x84/comet-46p-wirtanen-night-sky-map.png?1)
Brightest Comet of 2018
Comet 46P/Wirtanen will grace the night sky in December 2018. Find when, how, and where to see the brightest comet of the year with your naked eyes.
![Comet in the dark sky over a mountain with a setting/rising Sun in the background.](https://c.tadst.com/gfx/150x84/neowise-above-mountain-slovakia.jpg?1)
Brightest Comet of 2020
Comet C/2020 F3 NEOWISE will grace the night sky in July 2020. Find when, how, and where to see the brightest comet of the year with your naked eyes.
![Screenshot of timeanddate.com's Night Sky Map for December 21, 2020, shortly after sunset in the northern hemisphere.](https://c.tadst.com/gfx/150x84/night-sky-map-great-conjunction.jpg?1)
Great Conjunction 2020
In December 2020, Jupiter and Saturn met in the sky in a rare Great Conjunction.
![An image from our Night Sky Map showing all five naked-eye planets](https://c.tadst.com/gfx/150x84/six-planets-labels.png?1)
What Is a Planet?
A celestial body needs to pass three tests to be called a planet.
![NASA technicians work on the New Horizons spacecraft at the Kennedy Space Center in November 2005.](https://c.tadst.com/gfx/150x84/new-horizons.jpg?1)
The Solar System
Everything that orbits the Sun is part of the solar system.
![Telescope view of the Sun from Earth.](https://c.tadst.com/gfx/150x84/istock-936863548.jpg?1)
The Sun: Our Home Star
Energy from the Sun reaches Earth in the form of solar radiation, or sunlight.
![A view of the planet Mars.](https://c.tadst.com/gfx/150x84/mars.jpg?1)
Mars: The Red Planet
Mars is the outermost of the Solar System’s small inner planets.
![Venus captured by NASA's Mariner 10 spacecraft](https://c.tadst.com/gfx/150x84/4319.jpg?1)
Venus: Our Twin Planet
There is much that is similar—and much that is different—between Venus and Earth.
![A view of the Earth in space.](https://c.tadst.com/gfx/150x84/gibbous-earth.jpg?1)
Earth: The Living Planet
Earth is the largest of the Solar System’s rocky inner planets.
![A mosaic of Saturn made up of images taken by the Cassini spacecraft in October 2016.](https://c.tadst.com/gfx/150x84/saturn-rings-cassini.jpg?1)
Saturn: The Ringed Planet
Saturn is easily visible with the naked eye, although a small telescope is required to see its rings.
![A close-up of Uranus, taken by the Voyager 2 spacecraft in January 1986.](https://c.tadst.com/gfx/150x84/uranus.jpg?1)
Uranus: The Sideways Planet
Uranus is the seventh planet from the Sun. It was the first “new” planet to be discovered.
![A mosaic of images of Mercury taken by NASA's MESSENGER spacecraft.](https://c.tadst.com/gfx/150x84/mercury.jpg?1)
Mercury: The Iron Planet
Mercury, which is made mostly of iron, is the smallest planet, and the closest to the Sun.
![Jupiter and its moon Europa, as seen by the Hubble Space Telescope on August 25, 2020](https://c.tadst.com/gfx/150x84/jupiter.jpg?1)
Jupiter: The Massive Planet
Jupiter is fifth in line from the Sun, and the largest planet in the solar system.
![Image of Neptune against a black background.](https://c.tadst.com/gfx/150x84/neptune.jpg?1)
Neptune: The Farthest Planet
Neptune is too far away to be seen with the naked eye, but a good pair of binoculars can capture it.
![Illustration image](https://c.tadst.com/gfx/150x84/day-night-map.png?1)
99% of Earthlings See Sunlight on July 8 (And on Other Dates, Too)
Our Sun data confirm an internet meme claiming 99% of the world’s population gets sunlight at 11:15 UTC on July 8. But does it happen on other dates, too?
![sunlight across the globe](https://c.tadst.com/gfx/150x84/sunlight-fact-check-article.png?1)
99% Of Us See Daylight at This Moment (Or Do We?)
Is it really true that 99% of the world's population see daylight at 11:15 UTC on July 8?
![World map showing day, night, and twilight at 19:56 UTC on December 6.](https://c.tadst.com/gfx/150x84/day-night-dec-6.png?1)
Dec 6: Minute of Global Darkness
There's a moment each year when almost 9 in 10 people worldwide experience night.