# How long does sunlight take to reach Earth? > Sunlight takes about 8 minutes and 20 seconds to reach Earth. Live from NASA JPL: today's light time, why it changes in the year, and the Sun you see. HTML: https://www.theuniversecounts.com/solar-system/the-sun/sunlight-to-earth Numbers as of 2026-10-31 03:44 UTC. Live ones keep changing on the HTML page. Right now sunlight takes 8 m 15 s to reach Earth. In that time it crosses 149 million kilometres of space, moving at the speed of light, the fastest anything can go. So the Sun you see is never quite the Sun as it is. It is the Sun as it was a little over eight minutes ago. And the energy in that light is far older still: it spent thousands of years working its way out of the Sun before it set off. - Time sunlight takes to reach Earth, at today's Earth–Sun distance: 8 m 15 s - The Sun's distance from Earth: 148,535,526 km - Time until Earth's next perihelion (closest to the Sun): 63 d 22 h 48 m 27 s - Solar wind speed measured upstream of Earth: 350 km/s ## A short trip, for light The speed of light The Sun is a star, a huge ball of hot gas held together by its own gravity. Deep in its core, hydrogen fuses into helium, and that is where the energy in sunlight begins. What leaves the Sun's surface is light, and light is the fastest thing there is. It moves at 299,792.458 kilometres every second. At that speed it could circle Earth's equator in 0.13 seconds, and reach the Moon in 1.3 seconds. Even so, the gap to the Sun takes minutes to cross. The light warming your face left the Sun's surface 8 m 15 s ago. It was already on its way when you started reading this page. ## Nearer in January, farther in July Earth's orbit Earth's path round the Sun is not a perfect circle. It is a slightly stretched loop, so our distance changes through the year. We pass closest in early January, at about 147 million kilometres, and farthest in early July, at about 152 million. The next close pass is on 3 January 2027, and the next far one on 5 July 2027. So sunlight arrives a little sooner in January than in July. At the closest point it takes about 8.2 minutes, at the farthest about 8.5 minutes. That is not why we have seasons. In early January, when Earth is nearest the Sun, it is winter in the north. The seasons come from Earth's tilted axis, which turns each half of the planet towards the Sun for part of the year. Compared with how far away the Sun is, the change in distance makes little difference to our weather. ## The Sun you see is the past Looking back in time Because light takes time, every look at the sky is a look back. The Sun in your sky is the Sun of a few minutes ago. If something changed on its face, we would not see it for 8 m 15 s. What if the Sun vanished altogether? We would keep seeing it for those same minutes. Earth would also keep circling it for those minutes, because a change in gravity travels at the speed of light too. In 2017, gravitational waves and light from the same collision of two neutron stars reached Earth less than two seconds apart, after a trip of about 130 million years. Then the sky would go dark and Earth would carry straight on into space. The same is true for everything else up there, only more so. The light of Proxima Centauri, the nearest star after the Sun, left it about 4.2 years ago. ## A much longer journey, inside the Sun From the core to the surface The eight minutes are only the end of the trip. The energy in sunlight is made in the Sun's core, where hydrogen fuses into helium. Getting out of the Sun is the slow part. In the dense radiative zone the energy is absorbed and given off again countless times, a step at a time in a random direction. Higher up, in the convection zone, rising bubbles of hot gas carry it to the surface. How long it all takes is not known well. Careful calculations with models of the Sun's interior give answers between 10,000 and 170,000 years. Older textbooks print much bigger numbers, from rough sums that treat the Sun as the same density all the way through. Even the low end is longer than all of recorded history, about 5,200 years. When the energy in today's sunlight set out from the core, people like us were already alive: our species is about 320,000 years old. ## From the Sun to the other planets Across the solar system Sunlight reaches Mercury in about 3.2 minutes, Mars in about 13 minutes and Jupiter in about 43 minutes. Out at Neptune it arrives after about 4.2 hours. Out there it is also faint. Light spreads out as it travels. Above Earth's air, each square metre facing the Sun gets 1,361 watts of sunlight. At Neptune the same square metre gets 1.508 watts. Comparisons are computed live on the HTML page. ## FAQ ### How long does sunlight take to reach Earth? Right now 8 m 15 s. Over the year it runs from about 8.2 minutes in early January to about 8.5 minutes in early July, because Earth's distance from the Sun changes. At the average distance it is 8 m 19 s. ### How far is the Sun from Earth? Right now 149 million kilometres. On average it is about 150 million kilometres, the distance astronomers call one astronomical unit. ### Is Earth closer to the Sun in summer? No, not in the north. Earth is closest to the Sun in early January, in the northern winter, and farthest in early July. The seasons come from the tilt of Earth's axis, not from the distance. ### If the Sun went out, how long until we would notice? About 8 m 15 s. The last light it gave off would keep arriving for that long. Earth would keep orbiting for the same few minutes too, because changes in gravity also travel at the speed of light. ### How long does sunlight take to reach Mars and Pluto? About 13 minutes to reach Mars and about 5.5 hours to reach Pluto, at their average distances from the Sun. ### How old is the light from the Sun? The light itself left the Sun's surface about eight minutes ago. The energy it carries is far older: it took between 10,000 and 170,000 years to work its way out from the core. ## Related - [What is the Sun doing right now?](https://www.theuniversecounts.com/solar-system/the-sun/what-is-the-sun-doing-now.md) - [Geomagnetic storms](https://www.theuniversecounts.com/solar-system/space-weather/geomagnetic-storms.md) - [Where are the planets right now?](https://www.theuniversecounts.com/solar-system/planets/where-are-the-planets.md) - [Voyager 1](https://www.theuniversecounts.com/solar-system/spacecraft/voyager-1.md) The next time sunlight touches your skin, it will have been travelling for eight minutes, and inside the Sun for far longer than people have been writing things down. What would you do with eight minutes' notice? ## Sources - Age of our species, Homo sapiens, from the oldest known fossils (Estimated): [Nature: The age of the hominin fossils from Jebel Irhoud, Morocco, and the origins of the Middle Stone Age (Richter et al. 2017, Nature 546, 293)](https://www.nature.com/articles/nature22335) - Diameter of a grain of sand (Estimated): [USGS: USGS Open-File Report 2006-1195: Nomenclature](https://pubs.usgs.gov/of/2006/1195/htmldocs/nomenclature.htm) - Diameter of a regulation football (size 5) (Measured, with error): [The IFAB: Laws of the Game, Law 2 – The Ball](https://www.theifab.com/laws/latest/the-ball/) - Distance to Proxima Centauri (Measured, with error): [Astronomy & Astrophysics: Gaia Data Release 3: Summary of the content and survey properties (Gaia Collaboration, Vallenari et al. 2023)](https://doi.org/10.1051/0004-6361/202243940); [ESA: Gaia Data License](https://www.cosmos.esa.int/web/gaia-users/license) - Earth's average distance from the Sun in kilometres (Measured): [NASA: Earth: Facts](https://science.nasa.gov/earth/facts/) - Earth's circumference at the equator (Measured): [NASA NSSDCA: Earth Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html) - Earth's diameter at the equator (Measured): [NASA NSSDCA: Earth Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html) - Earth's distance from the Sun at aphelion (farthest) (Measured): [NASA NSSDCA: Earth Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html) - Earth's distance from the Sun at perihelion (closest) (Measured): [NASA NSSDCA: Earth Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html) - Great-circle distance between London and Sydney (Measured, with error): [NASA NSSDCA: Earth Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html) - Height of Mount Everest above sea level (Measured): [Survey Department, Government of Nepal: Measurement of Height of Mt. Sagarmatha (Journal on Geoinformatics, Nepal 20(1), 59–66)](https://doi.org/10.3126/njg.v20i1.39479) - Jupiter's average distance from the Sun (Measured): [NASA NSSDCA: Jupiter Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html) - Jupiter's diameter at the equator (Measured): [NASA NSSDCA: Jupiter Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html) - Length of recorded history, since the first writing (Estimated): [British Museum: How to write cuneiform](https://www.britishmuseum.org/blog/how-write-cuneiform) - Mars's average distance from the Sun (Measured): [NASA NSSDCA: Mars Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html) - Mercury's average distance from the Sun (Measured): [NASA NSSDCA: Mercury Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/mercuryfact.html) - Neptune's average distance from the Sun (Measured): [NASA NSSDCA: Neptune Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/neptunefact.html) - Pluto's average distance from the Sun (Measured): [NASA NSSDCA: Pluto Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/plutofact.html) - Solar wind speed measured upstream of Earth (Measured): [NOAA SWPC: Solar Wind Data and Display Changes (30 June 2026)](https://www.spaceweather.gov/news/solar-wind-data-and-display-changes); [NOAA SWPC: SWPC home-page summary bar script (shows this file as "Solar Wind Speed ... km/sec")](https://www.swpc.noaa.gov/modules/custom/swpc_summary/swpc_summary.js); [The Astrophysical Journal: Extremely Slow (Vsw < 300 km/s) Solar Winds (ESSWs) at 1 au: Causes of Extreme Geomagnetic Quiet at Earth (Tsurutani & Hajra 2022, ApJ 936, 155)](https://doi.org/10.3847/1538-4357/ac7444); [Journal of Geophysical Research: Extremely high speed solar wind: 29-30 October 2003 (Skoug et al. 2004, JGR 109, A09102)](https://doi.org/10.1029/2004JA010494); [Space Weather (AGU): On the Little-Known Consequences of the 4 August 1972 Ultra-Fast Coronal Mass Ejecta (Knipp et al. 2018, Space Weather 16)](https://doi.org/10.1029/2018SW002024) - Speed of light in a vacuum (Measured): [BIPM: SI defining constants](https://www.bipm.org/en/measurement-units/si-defining-constants) - Sunlight power on each square metre at Earth's average distance from the Sun (total solar irradiance) (Measured, with error): [The Astronomical Journal (IAU): Nominal values for selected solar and planetary quantities: IAU 2015 Resolution B3 (Prša et al., AJ 152, 41, 2016; text also at arXiv:1510.07674)](https://doi.org/10.3847/0004-6256/152/2/41); [NASA NSSDCA: Earth Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html) - Sunlight reaching Neptune, per square metre (mean solar irradiance) (Measured): [NASA NSSDCA: Neptune Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/neptunefact.html) - The International Space Station's orbital speed (Measured): [NASA: Station Facts](https://www.nasa.gov/international-space-station/space-station-facts-and-figures/) - The Moon's average distance from Earth (Measured): [NASA: Moon Facts](https://science.nasa.gov/moon/facts/) - The Moon's mean diameter (Measured): [NASA NSSDCA: Moon Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html) - The Sun's distance from Earth (Measured): [NASA NSSDCA: Sun Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html) - Time sunlight takes to reach Earth, at the mean Earth–Sun distance (1 au) (Measured): [International Astronomical Union (hosted by SYRTE, Observatoire de Paris): IAU 2012 Resolution B2 on the re-definition of the astronomical unit of length](https://syrte.obspm.fr/IAU_resolutions/Res_IAU2012_B2.pdf); [BIPM: SI defining constants](https://www.bipm.org/en/measurement-units/si-defining-constants); [NASA NSSDCA: Earth Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html) - Time sunlight takes to reach Earth, at today's Earth–Sun distance (Measured): [NASA JPL: JPL Horizons observer ephemeris of the Sun from Earth (range and one-way light time)](https://ssd.jpl.nasa.gov/api/horizons.api?format=text&COMMAND='10'&CENTER='500@399'&EPHEM_TYPE='OBSERVER'&QUANTITIES='20,21'&START_TIME='2026-10-28%2020:00'&STOP_TIME='2026-10-28%2021:00'&STEP_SIZE='1h') - Time the energy made in the Sun's core takes to reach the surface (Estimated): [NASA Science: Sun: Facts](https://science.nasa.gov/sun/facts/); [NASA Goddard Space Flight Center: Technology Through Time #50: Ancient Sunlight (Sun-Earth Day 2007)](https://spdf.gsfc.nasa.gov/pub/documents/old/websites/sunearthday.nasa.gov/2007/locations/ttt_sunlight.php) - Time until Earth's next aphelion (farthest from the Sun) (Measured): [NASA JPL: JPL Horizons API, Sun geocentric vectors (geometric), one-minute steps around the first date](https://ssd.jpl.nasa.gov/api/horizons.api?format=text&COMMAND='10'&OBJ_DATA='NO'&MAKE_EPHEM='YES'&EPHEM_TYPE='VECTORS'&CENTER='500@399'&START_TIME='2027-07-05%2003%3A36'&STOP_TIME='2027-07-05%2006%3A36'&STEP_SIZE='1m'&VEC_TABLE='3'&VEC_CORR='NONE'&OUT_UNITS='KM-S'&TIME_TYPE='UT'&CSV_FORMAT='YES'); [US Naval Observatory: Earth's Seasons and Apsides, 2027 (USNO Astronomical Applications API)](https://aa.usno.navy.mil/api/seasons?year=2027) - Time until Earth's next perihelion (closest to the Sun) (Measured): [NASA JPL: JPL Horizons API, Sun geocentric vectors (geometric), one-minute steps around the first date](https://ssd.jpl.nasa.gov/api/horizons.api?format=text&COMMAND='10'&OBJ_DATA='NO'&MAKE_EPHEM='YES'&EPHEM_TYPE='VECTORS'&CENTER='500@399'&START_TIME='2027-01-03%2001%3A03'&STOP_TIME='2027-01-03%2004%3A03'&STEP_SIZE='1m'&VEC_TABLE='3'&VEC_CORR='NONE'&OUT_UNITS='KM-S'&TIME_TYPE='UT'&CSV_FORMAT='YES'); [US Naval Observatory: Earth's Seasons and Apsides, 2027 (USNO Astronomical Applications API)](https://aa.usno.navy.mil/api/seasons?year=2027) - Typical muzzle velocity of a rifle bullet (Estimated): [Headquarters, Department of the Army: FM 3-22.9 Rifle Marksmanship: M16A1, M16A2/3, M16A4, and M4 Carbine (April 2003)](https://www.bits.de/NRANEU/others/amd-us-archive/FM3-22.9%2803%29.pdf)