# Where does the Solar System end? > Three answers to where the Solar System ends: the last planet, the heliopause and the Oort cloud. With Voyager 1's live distance past the edge. HTML: https://www.theuniversecounts.com/solar-system/the-edge/where-does-the-solar-system-end Numbers as of 2026-11-04 16:50 UTC. Live ones keep changing on the HTML page. It depends on what you mean by the edge. The planets stop at Neptune, 30.0690 AU from the Sun. The Sun's wind stops at the heliopause, roughly 120 AU out, where both Voyagers crossed into interstellar space. The Sun's gravity still holds the Oort cloud, which may reach 100,000 AU. Right now Voyager 1 is 25.8 billion kilometres from the Sun, past the heliopause and still moving out. - Time since Voyager 1 went interstellar: 14y 71d 4h - Time since Voyager 2 went interstellar: 7y 364d 22h - Voyager 2's distance from Earth: 21,642,416,333 km - Time for light from Earth to reach Voyager 1: 23h 58m 09s ## Three edges, not one What the edge means The Solar System is the Sun and everything it holds on to: eight planets, their moons, and countless smaller icy and rocky bodies. Asking where it ends is like asking where a town ends. There is the last house, the edge of the streetlights, and the line on the map, and they are in different places. The first edge is the last planet. Beyond Neptune lies the Kuiper belt, a ring of icy worlds that thins out around 50 AU. The second edge is where the Sun's wind gives way to the gas between the stars. The third is where the Sun's gravity stops being the strongest pull around. NASA uses the second edge when it says the Voyagers reached interstellar space. Yet NASA also calls the Oort cloud the most distant region of our Solar System. Both are true. They answer different questions. ## The bubble we live in The heliosphere The Sun blows a constant wind of charged particles in every direction. It leaves at hundreds of kilometres per second and carries the Sun's magnetic field with it. That wind inflates a huge bubble around us called the heliosphere. Far out, the wind meets the thin gas between the stars. First it slows sharply at a boundary called the termination shock. Then, at the heliopause, it stops pushing outward at all. The heliopause is roughly 120 AU from the Sun. Sunlight takes about 17 hours to get there. The bubble is not round. The Sun moves through the galaxy, so the bubble is squeezed on one side, like a boat's bow wave. How long its tail is, and whether it has one at all, is still debated. ## Two crossings, six years apart 25 August 2012 · 5 November 2018 Voyager 1 reached the termination shock on 16 December 2004, at 94.0 AU from the Sun. Voyager 2 reached it on 30 August 2007, at 83.7 AU. Voyager 2 met it much closer to the Sun, the first clear sign that the bubble is lopsided. Voyager 1 crossed the heliopause on 25 August 2012, at 121.6 AU. Voyager 2 followed on 5 November 2018. On that day its instruments counted far fewer of the low-energy particles that come from the Sun, and more cosmic rays from the rest of the Milky Way. The Sun's wind was behind it. ## How far the Sun's gravity reaches The Oort cloud Past the heliopause, the Sun's gravity still rules. Far beyond it, astronomers think a vast, thin shell of icy bodies surrounds us: the Oort cloud. No one has seen it directly. We infer it from the long, steep orbits of comets that fall in from it. NASA puts its inner edge somewhere between between 2,000 and 5,000 AU from the Sun. The outer edge may lie as far as 100,000 AU, though NASA gives a wide range. Out there, the pull of nearby stars and of the galaxy itself starts to match the Sun's. That fuzzy line is the widest answer to our question, and nobody knows exactly where it falls. New Horizons, heading the same way more slowly, is still inside the bubble. ## A very long trip Voyager 1, from here on Voyager 1 moves away from the Sun at about 16.92 kilometres per second. Even so, it will need roughly about 300 years just to reach the inner edge of the Oort cloud. Crossing the whole cloud would take it something like about 30,000 years. So by the widest answer, nothing we have built has left the Solar System yet. By NASA's interstellar answer, two have. Both spacecraft keep sending data from beyond the heliopause. ## The shield around us Why the bubble matters The heliosphere is more than a border on a map. Its magnetic field turns many cosmic rays away, the fast particles flung out by exploding stars across the galaxy. The Voyagers saw this when they crossed. The number of cosmic rays they counted jumped once they were outside. Earth's own magnetic field and air do the rest. We live inside two shields, one of them about 120 AU wide on its near side. Every planet, every life on Earth, has always sat within the Sun's bubble. Comparisons are computed live on the HTML page. ## FAQ ### At what point does the Solar System end? There is no single line. The planets end at Neptune, the Sun's wind ends at the heliopause about 120 AU out, and the Sun's gravity reaches into the Oort cloud, perhaps as far as 100,000 AU. ### What is the edge of a solar system called? For the Sun's wind, the edge is the heliopause, the outer wall of the bubble called the heliosphere. Inside it is the termination shock, where the wind first slows. For gravity, there is no special name; the outer edge of the Oort cloud is the usual answer. ### What did NASA find at the edge of the Solar System? When each Voyager crossed the heliopause, particles from the Sun dropped away and cosmic rays from the galaxy rose. Voyager 2 met the termination shock 83.7 AU from the Sun, closer than Voyager 1 did, which showed that the bubble is lopsided. ### Is the Oort cloud the edge of the Solar System? By the gravity answer, yes. NASA calls it the most distant region of our Solar System, with its inner edge between between 2,000 and 5,000 AU. It is still a theory, inferred from comets, not seen directly. ### Can we ever realistically leave the Solar System? Voyager 1 has left the Sun's bubble, but at its speed it needs about 30,000 years to pass the Oort cloud. Leaving by the widest definition would take any craft we can build today many thousands of years. ## Related - [The solar wind](https://www.theuniversecounts.com/solar-system/space-weather/solar-wind.md) - [Voyager 1](https://www.theuniversecounts.com/solar-system/spacecraft/voyager-1.md) - [Voyager 2](https://www.theuniversecounts.com/solar-system/spacecraft/voyager-2.md) - [The edge](https://www.theuniversecounts.com/solar-system/the-edge.md) Everything you have ever known has happened inside the Sun's bubble. What would you want to know about the space just beyond it? ## Sources - 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) - Distance from the Sun to the heliopause, where the Voyagers crossed it (Estimated): [American Geophysical Union: Voyager Observations of the Heliospheric Interface (AGU Fall Meeting 2014 abstract)](https://studio.m-anage.com/agu/fm14/webprogram/Paper4456.html); [Nature Astronomy: Magnetic field and particle measurements made by Voyager 2 at and near the heliopause (Burlaga et al. 2019, Nature Astronomy)](https://doi.org/10.1038/s41550-019-0920-y); [NASA: Voyager Interstellar Mission](https://science.nasa.gov/mission/voyager/interstellar-mission/) - Distance from the Sun to the inner edge of the Oort cloud (Debated): [NASA: Oort Cloud: Facts](https://science.nasa.gov/solar-system/oort-cloud/facts/) - Distance from the Sun to the outer edge of the main Kuiper belt (Estimated): [NASA: Kuiper Belt: Facts](https://science.nasa.gov/solar-system/kuiper-belt/facts/) - Distance from the Sun to the outer edge of the Oort cloud (Debated): [NASA: Oort Cloud: Facts](https://science.nasa.gov/solar-system/oort-cloud/facts/) - 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 (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) - 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 a light-year (Measured): [NASA JPL Solar System Dynamics: Astrodynamic Parameters](https://ssd.jpl.nasa.gov/astro_par.html) - Length of Neptune's orbit around the Sun (Measured): [NASA NSSDCA: Neptune Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/neptunefact.html) - Neptune's average distance from the Sun (Measured): [NASA NSSDCA: Neptune Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/neptunefact.html) - Speed of light in a vacuum (Measured): [BIPM: SI defining constants](https://www.bipm.org/en/measurement-units/si-defining-constants) - 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 mean diameter (Measured): [NASA NSSDCA: Moon Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html) - The Sun's mean diameter (Measured, with error): [NASA NSSDCA: Sun Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html); [International Astronomical Union / The Astronomical Journal: Prša et al. 2016, IAU 2015 Resolution B3 on Recommended Nominal Conversion Constants for Selected Solar and Planetary Properties](https://arxiv.org/abs/1510.07674) - Time for light from Earth to reach Voyager 1 (Measured): [NASA JPL: Horizons API documentation](https://ssd-api.jpl.nasa.gov/doc/horizons.html) - Time for Voyager 1 to pass beyond the Oort cloud (Estimated): [NASA: Voyager Frequently Asked Questions](https://science.nasa.gov/mission/voyager/frequently-asked-questions/) - Time for Voyager 1 to reach the inner edge of the Oort cloud (Estimated): [NASA: Voyager Frequently Asked Questions](https://science.nasa.gov/mission/voyager/frequently-asked-questions/) - Time since Voyager 1 went interstellar (Measured): [NASA: Voyager Interstellar Mission](https://science.nasa.gov/mission/voyager/interstellar-mission/); [American Geophysical Union: Voyager Observations of the Heliospheric Interface (AGU Fall Meeting 2014 abstract)](https://studio.m-anage.com/agu/fm14/webprogram/Paper4456.html) - Time since Voyager 2 flew past Neptune (Measured): [NASA: Voyager Fact Sheet](https://science.nasa.gov/mission/voyager/fact-sheet/) - Time since Voyager 2's launch (Measured): [NASA: Voyager 2](https://science.nasa.gov/mission/voyager/voyager-2/); [NASA NSSDCA: Voyager 2 (NSSDCA/COSPAR ID 1977-076A)](https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1977-076A) - Time since Voyager 2 went interstellar (Measured): [Nature Astronomy: Magnetic field and particle measurements made by Voyager 2 at and near the heliopause (Burlaga et al. 2019, Nature Astronomy)](https://doi.org/10.1038/s41550-019-0920-y); [Nature Astronomy: Voyager 2 plasma observations of the heliopause and interstellar medium (Richardson et al. 2019, Nature Astronomy)](https://doi.org/10.1038/s41550-019-0929-2); [NASA: Voyager Interstellar Mission](https://science.nasa.gov/mission/voyager/interstellar-mission/) - 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) - Voyager 1's distance from the Sun (Measured): [NASA JPL: JPL Horizons API, Voyager 1 heliocentric vectors (geometric)](https://ssd.jpl.nasa.gov/api/horizons.api?format=text&COMMAND='-31'&OBJ_DATA='NO'&MAKE_EPHEM='YES'&EPHEM_TYPE='VECTORS'&CENTER='500@10'&START_TIME='2026-10-18'&STOP_TIME='2026-10-19'&STEP_SIZE='1d'&VEC_TABLE='3'&VEC_CORR='NONE'&OUT_UNITS='KM-S'&TIME_TYPE='UT') - Voyager 1's distance from the Sun when it crossed the heliopause (Measured): [American Geophysical Union: Voyager Observations of the Heliospheric Interface (AGU Fall Meeting 2014 abstract)](https://studio.m-anage.com/agu/fm14/webprogram/Paper4456.html); [NASA: Voyager Interstellar Mission](https://science.nasa.gov/mission/voyager/interstellar-mission/) - Voyager 1's distance from the Sun when it crossed the termination shock (Measured, with error): [NASA: Voyager 1](https://science.nasa.gov/mission/voyager/voyager-1/) - Voyager 1's speed relative to the Sun (Measured): [NASA: Voyager 1: What Is a Light-Day?](https://science.nasa.gov/mission/voyager/voyager-1/voyager-1-what-is-a-light-day/) - Voyager 2's distance from Earth (Measured): [NASA JPL: JPL Horizons API, Voyager 2 geocentric vectors (geometric)](https://ssd.jpl.nasa.gov/api/horizons.api?format=text&COMMAND='-32'&OBJ_DATA='NO'&MAKE_EPHEM='YES'&EPHEM_TYPE='VECTORS'&CENTER='500@399'&START_TIME='2026-10-18'&STOP_TIME='2026-10-19'&STEP_SIZE='1d'&VEC_TABLE='3'&VEC_CORR='NONE'&OUT_UNITS='KM-S'&TIME_TYPE='UT') - Voyager 2's distance from the Sun when it crossed the heliopause (Measured): [Nature Astronomy: Magnetic field and particle measurements made by Voyager 2 at and near the heliopause (Burlaga et al. 2019, Nature Astronomy)](https://doi.org/10.1038/s41550-019-0920-y); [Nature Astronomy: Cosmic ray measurements from Voyager 2 as it crossed into interstellar space (Stone et al. 2019, Nature Astronomy)](https://doi.org/10.1038/s41550-019-0928-3); [NASA JPL: Voyager 2 Illuminates Boundary of Interstellar Space](https://www.jpl.nasa.gov/news/voyager-2-illuminates-boundary-of-interstellar-space) - Voyager 2's distance from the Sun when it crossed the termination shock (Measured, with error): [Nature: An asymmetric solar wind termination shock (Nature 454, issue summary)](https://doi.org/10.1038/nature07022); [NASA: Voyager 2](https://science.nasa.gov/mission/voyager/voyager-2/)