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LED+ Dusk to Dawn bulb is up all night, so you can rest. With a built-in light sensor, this long lasting and energy efficient bulb automatically illuminates to brighten the night. Add to any outdoor fixture for an easy sense of security.

  • Upgrade Your Home With Led Light Bulbs: The LED+ dusk to dawn light sensor bulbs are up all night, so you can rest. These LED light bulbs automatically illuminate to brighten the night with cool, bluish white daylight
  • Energy Efficient Led Light Bulbs: The A21 LED light bulb with a dusk to dawn sensor perfectly replaces your damp-rated outdoor 100-Watt light bulbs and uses only 13 watts, extending the life of your LED lights and reducing your energy costs
  • Automatic Dusk To Dawn Led Outdoor Lighting: These LED+ damp-rated outdoor light bulbs feature a simple, built-in sensor that detects ambient light to calculate when to power on and off with no scheduling required
  • Damp-Rated Outdoor Led Light Bulbs 100-Watt Equivalent: Get the efficiency of low wattage light bulbs. The LED+ damp-rated outdoor A21 LED light bulbs are the easiest way to cut costs without sacrificing brightness or automated functionality
  • 100 Watt replacement using only 13 Watts (1600 lumens)
  • A21 shape and size with frosted finish
  • Medium base (E26)

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LED Dusk-to-Dawn Outdoor Lights | Buy Commercial Dusk to Dawn Flood Lights & Fixtures

When you need lights for nighttime operation, check out our dusk-to-dawn outdoor lights to get the results you expect. There are many advantages to using dusk-to-dawn flood lights over more traditional options. The main feature is a built-in sensor that enables the light to turn itself on at dusk and back off as soon as the sun comes up. Along with being an ideal outdoor security lighting application, dusk-to-dawn lights are a great solution for energy saving. Also, the durable construction of our LED dusk-to-dawn outdoor lights provides an outstanding level of reliability in any situation, making them perfect for exterior use. With resistance to weather and debris, they will function for years, giving you the light you need to guide the way when the sun sets. Trust Warehouse-Lighting.com for the best dusk-to-dawn outdoor flood lights.

10 products

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WareLight LED Dusk to Dawn, 65W, 5000K, Silver Gray or Dark Bronze Housing, 120-277V, Arm Included

  • Brand: WareLight
  • Wattage: 65
  • Voltage: 120-277
  • Multi-volt Photo Cell Included
  • Lumens: 8800
  • CCT: 5000K
  • CRI: 80
  • L70 Life: 50,000 hours
  • Listings: cULus, Wet Location Listed
  • Finish: Silver Gray or Bronze
  • Wall Mount with or without Included Mounting Arm 
  • 5 year warranty


Regular price$148. 70


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WareLight LED Dusk to Dawn, 90W, 5000K, Silver Gray or Dark Bronze Housing, 120-277V, Arm Included

  • Brand: WareLight
  • Wattage: 90
  • Voltage: 120-277
  • Multi-volt Photo Cell Included
  • Lumens: 12200
  • CCT: 5000K
  • CRI: 80
  • L70 Life: 50,000 hours
  • Listings: cULus, Wet Location Listed
  • Finish: Silver Gray or Bronze
  • Wall Mount with or without Included Mounting Arm 
  • 5 year warranty


Regular price$149.98


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Dusk to Dawn Light with Photocell, 45W, 65W or 90W, 4000K or 5000K, 120-277V, Silver Finish

  • Brand: GKOLED
  • Wattage: 45W / 65W / 90W
  • Lumens: 6200 / 8800 / 12400
  • CCT: 4000K or 5000K
  • Voltage: 120-277
  • Finish: Silver 
  • Included twist lock photocell
  • Optional mounting arm available
  • Listings: DLC, UL Listed for wet locations
  • 5 year warranty


Regular price$111. 82


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Dusk to Dawn Light with Photocell, 45W, 65W or 90W, 4000K or 5000K, 120-277V, Dark Bronze Finish

  • Brand: GKOLED
  • Wattage: 45W / 65W / 90W
  • Lumens: 6200 / 8800 / 12400
  • CCT: 4000K or 5000K
  • Voltage: 120-277
  • Finish: Dark Bronze
  • Included twist lock photocell
  • Optional mounting arm available
  • Listings: DLC, UL Listed for wet locations
  • 5 year warranty


Regular price$111.82


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Led Area Dusk to Dawn Light with Photocell, 7,800 Lumens, 36W/42W/60W Selectable, 120-277V, CCT Selectable 3000K/4000K/5000K, Grey Finish

  • Brand: Westgate Manufacturing
  • Finish: Grey
  • Wattage Selectable / Lumens:
    • 36W / 4,680LM
    • 42W / 5,460LM
    • 60W / 7800LM
  • CCT Selectable: 3000K/4000K/5000K
  • Mounting Strap Included
  • DC Button Photocell Included
  • Dimming: 0-10V Dimming
  • CRI: > 80
  • Rated life: 70,000 Hrs
  • Listings: UL, IP65, Wet Locations
  • 7 Year Warranty


Regular price$131. 99


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Area Barn Dusk to Dawn w/ Photocell, 40W or 60W, Silver or Bronze Finish

  • Brand: Envision
  • Wattage: 40W or 60W
  • Voltage: 120-277
  • CCT: 3000K/4000K/5000K
  • CRI: >80
  • Rated Lifetime: 50,000 hours
  • Dimming: 0-10V
  • Lumens:
    • 40W = 6200
    • 50W = 9300
  • Listings: IP 67, DLC Premium, UL
  • Includes Photocell
  • 5 year warranty


Regular price$141.70


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Led Area Dusk to Dawn Light, 6,800 Lumens, 20W/30W/40W/50W Selectable, 120-277V, CCT Selectable 3000K/4000K/5000K/5700K, Dark Bronze Finish

  • Brand: Westgate Manufacturing
  • Finish: Dark Bronze
  • Wattage Selectable: 20W/30W/40W/50W
  • CCT Selectable: 3000K/4000K/5000K/5700K
  • Lumens: 2950-6800LM (See spec for details)
  • Dimming: 0-10V Dimming
  • CRI: > 70
  • Rated life: 70,000 Hrs
  • Listings: UL, DLC, IP44, Wet Locations
  • 7 Year Warranty


Regular price$197. 99


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LED Dusk to Dawn Barnlight, 60W, 7800 Lumens, Wattage and CCT Selectable, 120-277V

  • Brand: Maxlite
  • Voltage: 120-277V
  • Selectable CCT: 3000/4000/5000K
  • Selectable Wattage: 34 / 48 /60
  • Lumens: 7130-7850
  • CRI: 80+
  • Dimming: 0-10V
  • Operating Temperature: -40° – 122°F 
  • Distribution Type: Type V
  • Includes c-Max photocell
  • Listings: DLC Premium, IP65, UL listed for Wet Locations, Outdoor
  • Warranty: 5 years


Regular price$260.38


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Led Area Dusk to Dawn Light with Photocell, 15,600 Lumens, 72W/96W/120W Selectable, 120-277V, CCT Selectable 3000K/4000K/5000K, Grey Finish

  • Brand: Westgate Manufacturing
  • Finish: Grey
  • Wattage Selectable / Lumens:
    • 72W / 9,360LM
    • 96W / 12,480LM
    • 120W / 15,600LM
  • CCT Selectable: 3000K/4000K/5000K
  • Mounting Strap Included
  • NEMA Twist-Lock Photocell Included
  • Dimming: 0-10V Dimming
  • CRI: > 80
  • Rated life: 70,000 Hrs
  • Listings: UL, IP65, Wet Locations
  • 7 Year Warranty


Regular price$263. 99


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Led Dusk to Dawn Area Light, 17,000 Lumens, 50W/60W/100W/120W Selectable, 120-277V, CCT Selectable 3000K/4000K/5000K/5700K, Dark Bronze Finish

  • Brand: Westgate Manufacturing
  • Finish: Dark Bronze
  • Wattage Selectable: 50W/80W/100W/120W
  • CCT Selectable: 3000K/4000K/5000K/5700K
  • Lumens: 7,800-17,000LM (See spec for details)
  • Dimming: 0-10V Dimming
  • CRI: > 70
  • Rated life: 70,000 Hrs
  • Listings: UL, DLC, IP44, Wet Locations
  • 7 Year Warranty


Regular price$431.99


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The Benefits of Dusk-to-Dawn Lights

Dusk-to-dawn flood lights can be used in a range of commercial applications to ensure your business stays adequately illuminated during the night. There are many advantages to installing this type of lighting on your property. Following are some of the best reasons for choosing dusk-to-dawn lights.

Reduce Crime

Businesses use dusk-to-dawn fixtures because they make ideal security lights and help to deter crime. Intruders will think twice about breaking into a well-illuminated property because there is a better chance their actions will be witnessed by passersby and captured on security cameras. For this same reason, dusk-to-dawn lights are also an excellent application for residential yard lights .

Provide Safe Passage for Workers and Visitors

Whether you need to light your building’s perimeter, parking lot or walkway, commercial dusk-to-dawn outdoor lights are the solution. Anyone who needs to access your property after dark has to use lighted walkways to get where they’re going without tripping, stumbling into something or otherwise injuring themselves. For this reason, you also need outdoor garage lights – dusk-to-dawn – to illuminate the exterior of your garage. In fact, every building on your property should be well-lit. By installing outdoor barn lights, dusk-to-dawn illumination of your buildings is assured.

Ensure Compliance

Local zoning laws typically specify the type and placement required for commercial dusk-to-dawn outdoor lights. At Warehouse-Lighting.com, we’re well-versed in outdoor lighting requirements, so you can be assured the dusk-to-dawn flood lights you choose will comply with required safety standards.

Perform Even in Bad Weather

Commercial dusk-to-dawn outdoor lights are intended for exterior use and therefore are manufactured to meet specific criteria. For example, dusk-to-dawn lights are water-resistant to withstand wet conditions. They are also made with durable housings and lenses to further ensure longevity and performance for years to come.

Why LED Dusk-to-Dawn Outdoor Lights Are the Best Option

If you choose LED dusk-to-dawn outdoor lights, you’ll enjoy these added benefits:

  • More Efficient: LED dusk-to-dawn lights have a very long life and are more efficient than other lighting options, which is crucial because they are used every day and turned on for long periods of time.
  • Cost Effective: Without requiring frequent replacement, using LED lamps cuts down on maintenance costs and time. Everyone loves hearing about ways to save energy with lighting.
  • Easy on Fixtures: LED lights are a low-to-no heat option, which helps to extend the life of the fixture’s driver.
  • No Flickering: LED dusk-to-dawn outdoor lights are instant-on when powered up – they don’t flicker or need to warm up.
  • Even Illumination: The light from LEDs is uniform and tends not to degrade over time.

Frequently Asked Questions About Dusk-to-Dawn Outdoor Lights

Hopefully, answering these questions about dusk-to-dawn lights will help you choose the right lighting for your property. If you have additional questions, please let us know.

How Do Dusk-to-Dawn Lights Work?

Dusk-to-dawn lighting has certain characteristics that are essential to its primary function. One of them is a photocell/sensor that automatically turns the light on or off depending on the presence of daylight. Another characteristic is its mounting options. They are usually mounted outdoors to a wall or a pole to provide a wide distribution of light.

What Types of Dusk-to-Dawn Flood Lights Do You Have?

We have a wide selection of LED dusk-to-dawn outdoor lights from brands like WareLight, MaxLite and GKO. A service road, a construction area, the perimeter of a building, a driveway or a large parking lot could all benefit from the security provided by lighting that lasts all night. Our models come with extended arms for easy installation anywhere you need, so you can get a light in the perfect location without extra hardware.

What Certifications Come With Commercial Dusk-to-Dawn Outdoor Lights?

Dusk-to-dawn outdoor wall lights are certified for wet locations, and with a highly-durable housing, every fixture has been specifically designed to provide many years of outdoor service. Take advantage of our highly efficient and long-lasting fixtures and enjoy powerful illumination every night without hassle.

Where Are Dusk-to-Dawn Lights Used?

Dusk-to-dawn lighting can be found on barns, retail businesses, grocery stores, alleys, construction areas, parking lots, driveways and service roads. Below are some examples of ideal locations for dusk-to-dawn lights:

Find the Best Dusk-to-Dawn Outdoor Lights at Warehouse-Lighting.com

At Warehouse-Lighting. com, you can choose from many options of dusk-to-dawn flood lights, including various wattages and designs that will match your specifications. And if you need outdoor lighting with motion sensor lights, we can help you there, too. You don’t need to suffer the darkness ever again – our fixtures are highly affordable and the best quality available. If you need assistance finding the best dusk-to-dawn outdoor flood lights with the right level of illumination and performance, feel free to contact us. We are always happy to help!

Articles Related to Dusk-to-Dawn Outdoor Lights

Astronomical, navigational and civil twilight | Twilight is when | When is the golden hour

In this article, we talk in detail about twilight and related concepts – sunset and dawn, golden hour, regime time, complete darkness. You will learn how these concepts differ, what types are divided into and learn how to determine their exact time for your location. Let’s deal with these terms once and for all!


  • What is twilight?
    • Types of twilight
    • Civil Twilight
    • Navigation twilight
    • Astronomical twilight
    • Twilight is when?
    • How long does twilight last?
  • What is sunrise and sunset?
    • Difference between sunrise and sunset
    • Is twilight the same as sunrise and sunset?
  • What is golden hour and blue hour?
    • What is the golden hour?
    • When is the golden hour?
    • What is blue hour?
    • Blue hour – when is this?
  • What is total darkness?
  • What is light pollution?

Take a look at our infographic that clearly explains what dusk, sunset, dawn and light pollution are.

When does dusk come? What types are they? What is golden hour? Our infographic will answer these questions and more.

View infographic

What is twilight?

Twilight is the interval of time during which the Sun has already disappeared behind the horizon line, but still partially illuminates the sky. Twilight is due to the fact that the Earth has an atmosphere in which the light is partially scattered and illuminates our planet even when the Sun is no longer visible.

Types of twilight

There are three types of twilight – civil, nautical and astronomical. They come in succession; twilight is divided into different types depending on the location of the geometric center of the Sun under the horizon:

  • Civil twilight : 0-6°
  • Nautical twilight : 6-12°
  • Astronomical twilight : 12–18°

The period when the Sun falls below 18° is called night.

Civil twilight

This is the brightest phase; most people have her in mind when it comes to twilight. Civil twilight occurs just before sunrise or after sunset. At this time, the horizon line is clearly visible, and only the brightest stars and planets are visible in the sky. In many countries, the law requires that street lights and dipped headlights on cars be turned on at this time.

Immediately after sunset, the sky is still very bright and shimmers with many different colors. To capture the different shades in the sky, it is best to catch the very beginning of civil evening twilight.

Nautical twilight

This is the second stage when the horizon line is no longer so easy to see. The concept itself came to us from the past, when sailors used the stars to navigate. During nautical twilight, you can already see many more stars and determine your location according to their position.

At this time, artificial lighting is already fully illuminating cities, so nautical twilight is well suited for urban photography. If we talk about astrophotography, then you have a chance to catch the full moon on the horizon. This way you can photograph dark silhouettes against the background of the moon.

Astronomical twilight

When it is almost completely dark outside, and the horizon is almost indistinguishable, astronomical twilight sets in. The Milky Way begins to appear in the sky, and even dim stars and planets can now be seen with the naked eye (of course, if the Moon does not illuminate the sky). However, galaxies, nebulae and star clusters are still best observed during complete darkness, when the Sun has already dropped below 18 ° below the horizon.

This is a great time for photographs and observations of celestial bodies. If you can see the Milky Way at your location (check Ephemeris for the time), try photographing this incredible galaxy.

Twilight is when?

The duration of twilight differs in different parts of the planet, so there is no single time for the beginning of twilight. How, then, to determine when astronomical twilight occurs? Use an app or website.


  • Sky Tonight is an advanced astronomy application. In the “Sky” tab in the calendar, you will find detailed graphs with the time of twilight, daylight hours and total darkness for your location.
  • Ephemeris is a handy tool for planning outdoor photos. It shows the exact time of civil, nautical and astronomical twilight, calculates the time and duration of the golden hour and regime time, contains detailed information about the visibility of the Milky Way and much more.
  • PhotoPills is a tool for (mostly) landscape photography that allows you to plan outdoor shots. In addition, there are dozens of articles on their website that will be useful to novice astrophotographers.
  • Sun Surveyor is an application that shows the trajectories of the Sun and Moon in augmented reality. Good for visualizing future photos.
  • Photographer’s Ephemeris is a map application containing calculations of the paths of the Sun, Moon and Milky Way. It will help to plan a photo shoot in nature, taking into account natural light.


  • Time and Date – On this site you will find detailed sunset and sunrise information for your location.
  • Sun Today – Shows all information related to the Sun (sunrise, sunset, twilight, noon, and more).

How long is twilight?

The duration of twilight depends on latitude, time of year and weather conditions. The shortest twilight can be observed near the equator, where darkness sets in 24 minutes after sunset; the longest twilight can last about six weeks near the poles.

What is sunrise and sunset?

Dawn (dawn) and sunset (dusk) are certain moments depending on the position of the Sun relative to the horizon . It is customary to distinguish three types of sunrise and sunset. They are determined by dipping the center of the Sun under the horizon line:

  • Civil sunset / dawn : 6°
  • Nautical sunset / dawn : 12°
  • Astronomical sunset / sunrise : 18°

The difference between sunrise and sunset

So what is the difference between sunrise and sunset? They belong to different periods. Sunset occurs in the evening when the sun sets below the horizon and the sky gradually darkens. Dawn comes in the morning, with the sunrise, when it begins to get light.

Is twilight the same as sunrise and sunset?

There is often confusion between dusk, dawn and sunset. In fact, they are completely different events. Sunset and dawn are moments when the center of the Sun is at a certain point below the horizon; twilight is the time interval between these points. For example, when the Sun is 18° below the horizon, this is called astronomical sunset (or dawn), but the interval from 12 to 18° is already astronomical twilight.

What is the golden hour and the blue hour?

There are two more terms closely related to twilight – golden hour and regime time. Let’s look into them.

What is the golden hour?

Photographers use the concept of the golden hour to define the period of day around sunrise and sunset, when daylight takes on a reddish tinge and becomes softer than when the Sun is high in the sky . Golden hour is perfect for filming:

  • Silhouettes;
  • Natural scenery;
  • Cityscapes;
  • full moon;
  • Portraits.

When is the golden hour?

Different sources define the beginning and end of the golden hour in different ways. For example, the PhotoPills website says that golden hour occurs when the Sun is between 6° above the horizon and 4° below it. Our [Ephemeris app] uses the same boundaries. But the Photo Ephemeris blog defines golden hour as the period when the Sun is between 0° and 6° above the horizon. The actual boundaries of the golden hour depend on the desired shots, the amount and characteristics of sunlight on them.

What is blue hour?

The blue hour (blue hour) is the period of the day when the Sun has already set below the horizon and the remaining visible sunlight takes on a blue tint . This time is good for those who want to take unique pictures:

  • Cities;
  • Nature;
  • moons;
  • Wild animals;
  • Architectural structures.

When is the blue hour?

The beginning and end of the regime time may differ in different sources. The Time and Date website defines regime time as partially covering civil and nautical twilight and occurs when the Sun is between 4° and 8° below the horizon. Other sources, like PhotoPills or the Ephemeris app, define duty time as the period when the Sun is 4° to 6° below the horizon (i.e. civil twilight only). As with the golden hour, each photographer determines the exact period of regime time for himself, depending on the lighting that he wants to get.

What is complete darkness?

We’ve dealt with what happens during twilight, but what comes after of them? The most interesting time for those who like to watch the night sky is total darkness. This is a colloquial term that means the period after the end of the evening astronomical twilight and before the beginning of the morning, when the moon does not light up the sky.

Total darkness is great for observing cosmic objects, especially dim objects like distant galaxies or star clusters.

Use the Sky Tonight app to find out when it’s completely dark in your location. Launch the application, click on the calendar icon at the bottom of the screen and select the “Sky” tab. Sky Tonight will show you the beginning and end of complete darkness and its duration.

What is light pollution?

But even the exact time of total darkness won’t help you see dim stars if you live in a city with heavy light pollution. In a general sense, light pollution (or glare) is excessive or unwanted artificial lighting . The most common examples are:

  • Street lamps;
  • Automobile headlights;
  • Skyscrapers;
  • Billboards.

Exposure has many harmful effects; within the framework of astronomical observations, one of these consequences is a decrease in the visibility of celestial objects. In the city center, even the brightest stars are barely visible, not to mention the constellations and planets. Excessive light is currently preventing approximately one-third of humanity from seeing the Milky Way in the night sky!

Therefore, articles about stargazing advise you to go as far as possible from the city – the average sky in the city is illuminated 10 times more than usual.

Lighting in the night sky is due to lighting devices that direct light upwards into the sky . Such light is scattered and reflected in the atmosphere, then returns to Earth and blinds us, thereby reducing the visibility of the night sky. This effect operates not only at the lighting device itself – it can be felt even far from the original source.

Read our article to learn more about light pollution and its effects on human and animal health.

Summing up : civil twilight is not good for observing the night sky, but during nautical twilight many more stars can already be seen. The best time to look for stars and planets is during astronomical twilight, and for deep sky objects at night when total darkness begins. By knowing the time of complete darkness, you will get the best time for observing when the moon does not light up the sky. And don’t forget to stay away from city lights, otherwise you’ll only see the Moon and the brightest stars at best.

Our apps will help you in observing the night sky, so download the app that best suits your needs in advance. And don’t forget to turn on the night mode – it will save your night vision!

We wish you clear skies and good observations!

Dawn, dusk and twilight | Meanings and dates


How to calculate the exact moment of sunrise or sunset?

When is sunrise and sunset?

We all know that sunrise or dawn is when the sun rises, and sunset or dusk is when it sets.

But what if we need a more precise time to call?

For example, astronomers at the Royal Greenwich Observatory find it useful to know exactly where the Sun is in the sky when it comes to whether an astronomical event will be visible.

super moon astrology 2016

In cases like this, we need to understand a little more clearly what we mean by sunrise and sunset.

images of Queen Elizabeth 1

Sunrise and sunset times: an astronomical explanation

Published times of sunrise and sunset refer to the time when The upper limb of the Sun , subject to the influence of refraction, is at the observer’s true horizon at sea level.

This occurs when the center of the Sun 50 arc minutes below the true horizon, the upper limb is then 34 arc minutes (slightly more than the apparent diameter of the Sun) below the true horizon.

What is twilight?

There are three different definitions of twilight:

Civil twilight

This is when the Sun’s center is 6° below the horizon, which roughly corresponds to the ignition time.

Turn-on time is the time during the day or evening when the law states that vehicles must have their headlights on. In the UK, this is 30 to 60 minutes after sunset.

During civil twilight, the brightest stars are visible, and the horizon is clearly defined on the sea.

chinese new year 2021 calendar

Nautical twilight

This is when the center of the Sun is 12° below the horizon, and is in fact the time when it is dark. It is known as nautical twilight because this is the time when sailors can use the positions of known stars in relation to the horizon to navigate.

Astronomical twilight

This is when the center of the Sun is 18° below the horizon. It’s really dark now, and no remnants of the solar afterglow are visible. The faintest stars can be seen from above.

Why not the earliest sunrise on the longest day of the year?

The longest and shortest days of the year are the days with the most and least amount of daylight. They occur around solstice around June 21st and December 21st in the UK and much of the northern hemisphere.

Many people notice that sunrise continues to come later after the winter solstice. The reason for this lies in the slight variation in the length of “natural” days throughout the year (the longest natural day is about 51 seconds longer than the shortest).

edward vii queen victoria

In order for the clock to work, all measured days must have a fixed, equal length. Thus, one fixes on the average length of a natural day (hence the ‘mean’ time GMT). By averaging the length of each day in this way, the time on the clock at which the sun reaches its highest point slowly shifts back and forth as the months pass.

Sunrise and sunset times have a linear effect. The earliest sunrise occurs a few days before the longest day, and the latest a few days after the shortest.

Discover gifts from the house of time

Keep track of the time with the Royal Observatory Greenwich clock and our famous Shepherd Gate clock reproduced on your wall of the house.

John Harrison h5 style gold pocket watch shop at Royal Observatory Greenwich £150. Stunningly crafted gold-plated Half Double Hunter pocket watch inspired by John Harrison’s world-changing chronometer…buy nowShop Greenwich Shepherd Gate Wall Clock 45cm, 24-Hour Analog Dial £150. Buy the Shepherd Gate 45 cm watch, which is sold exclusively in the GMT department. A stylish 24-hour analog clock with a bold monochrome dial and matte black metal case that will grace any wall…buy nowShop About Time Too: Collection of Time from the Royal Observatory Greenwich £12.99 How old is the Earth? How fast do you think? How long is a light year and how many femtoseconds? What does Greenwich Mean Time mean? Can you tell the time with colors? When did time begin? This hilarious illustrated collection from the Royal Observatory Greenwich answers some of these questions, as well as a host of other amazing facts and figures that show the impact of time on our daily lives.