Editing Voyager program (section)

{{Short description|Ongoing NASA interstellar program}}
{{Use American English|date=January 2014}}
{{Use dmy dates|date=September 2019}}

[[File:Voyager probes with the outer worlds.jpg|thumb|250px|A poster of the planets and moons visited during the Voyager program.]]

The '''Voyager program''' is an American scientific program that employs two [[interstellar probe]]s, ''[[Voyager 1]]'' and ''[[Voyager 2]]''. They were launched in 1977 to take advantage of a favorable planetary alignment to explore the two gas giants [[Jupiter]] and [[Saturn]] and potentially also the ice giants, Uranus and Neptune—to [[Flyby (spaceflight)|fly near them]] while collecting data for transmission back to Earth. After ''Voyager 1'' successfully completed its flyby of Saturn and its moon [[Titan (moon)|Titan]], it was decided to send ''Voyager 2'' on flybys of [[Uranus]] and [[Neptune]].<ref name="The Fantastic Voyage of Voyager">{{cite web|title=The Fantastic Voyage of Voyager|url=https://www.theattic.space/home-page-blogs/2020/1/9/the-astonishing-voyage-of-voyager|website=The Attic|date=9 January 2020|access-date=3 March 2020|archive-date=13 April 2020|archive-url=https://web.archive.org/web/20200413080737/https://www.theattic.space/home-page-blogs/2020/1/9/the-astonishing-voyage-of-voyager|url-status=live}}</ref> 

After the planetary flybys were complete, decisions were made to keep the probes in operation to explore [[Outer space|interstellar space]] and the outer regions of the Solar System. On 25 August 2012, data from ''Voyager 1'' indicated that it had entered interstellar space.<ref name="JPL.NASA" /> On 5 November 2019, data from ''Voyager 2'' indicated that it also had entered interstellar space.<ref name="NASA-20181210" /> On 4 November 2019, scientists reported that on 5 November 2018, the ''Voyager 2'' probe had officially reached the [[interstellar medium]] (ISM), a region of [[outer space]] beyond the influence of the [[solar wind]], as did ''Voyager 1'' in 2012.<ref name="EA-20191104">{{cite news |author=University of Iowa |title=Voyager 2 reaches interstellar space – Iowa-led instrument detects plasma density jump, confirming spacecraft has entered the realm of the stars |url=https://www.eurekalert.org/pub_releases/2019-11/uoi-v2r103119.php |date=4 November 2019 |work=[[EurekAlert!]] |access-date=4 November 2019 |author-link=University of Iowa |archive-date=13 April 2020 |archive-url=https://web.archive.org/web/20200413080722/https://www.eurekalert.org/pub_releases/2019-11/uoi-v2r103119.php |url-status=live }}</ref><ref name="NYT-20191104">{{cite news |last=Chang |first=Kenneth |title=Voyager 2's Discoveries From Interstellar Space – In its journey beyond the boundary of the solar wind's bubble, the probe observed some notable differences from its twin, Voyager 1. |url=https://www.nytimes.com/2019/11/04/science/voyager-2-interstellar-solar-wind.html |date=4 November 2019 |work=[[The New York Times]] |access-date=5 November 2019 |archive-date=13 April 2020 |archive-url=https://web.archive.org/web/20200413080724/https://www.nytimes.com/2019/11/04/science/voyager-2-interstellar-solar-wind.html |url-status=live }}</ref><ref name="NASA-Solar-System">{{cite web |url=https://solarsystem.nasa.gov/missions/voyager-1/in-depth/ |title=Solar System Exploration |publisher=JPL-NASA |access-date=19 February 2021 |archive-date=18 April 2019 |archive-url=https://web.archive.org/web/20190418200450/https://solarsystem.nasa.gov/missions/voyager-1/in-depth/ |url-status=live }}</ref> In August 2018, NASA confirmed, based on results by the ''[[New Horizons]]'' spacecraft, the existence of a "[[Heliosphere#Hydrogen wall|hydrogen wall]]" at the outer edges of the Solar System that was first detected in 1992 by the two Voyager spacecraft.<ref name="GRL-20180807">{{cite journal |author=Gladstone, G. Randall|display-authors=etal |title=The Lyman-α Sky Background as Observed by New Horizons
|date=7 August 2018 |journal=[[Geophysical Research Letters]] |volume=45 |issue=16 |pages=8022–8028 |doi=10.1029/2018GL078808 |arxiv=1808.00400 |bibcode=2018GeoRL..45.8022G |s2cid=119395450 }}</ref><ref name="LS-20180809">{{cite web |last=Letzter |first=Rafi |title=NASA Spotted a Vast, Glowing 'Hydrogen Wall' at the Edge of Our Solar System |url=https://www.livescience.com/63297-hydrogen-wall-glowing-interstellar-space.html |date=9 August 2018 |work=[[Live Science]] |access-date=10 August 2018 |archive-date=13 April 2020 |archive-url=https://web.archive.org/web/20200413080736/https://www.livescience.com/63297-hydrogen-wall-glowing-interstellar-space.html |url-status=live }}</ref><ref>{{Cite web|url=https://voyager.jpl.nasa.gov/frequently-asked-questions/fact-sheet/|title=Voyager – Fact Sheet|website=voyager.jpl.nasa.gov|access-date=17 May 2018|archive-date=13 April 2020|archive-url=https://web.archive.org/web/20200413080739/https://voyager.jpl.nasa.gov/frequently-asked-questions/fact-sheet/|url-status=live}}</ref>

{{As of|2024|post=,}} the Voyagers are still in operation beyond the outer boundary of the [[heliosphere]] in [[interstellar space]]. ''Voyager 1'' is moving with a velocity of {{convert|61,198|km/h|sp=us}}, or 17&nbsp;km/s, (10.5 miles/second) relative to the Sun, and is {{convert|24,475,900,000|km|sp=us}} from the Sun<ref name="JPL.Voyager1">{{cite web |url=https://voyager.jpl.nasa.gov/mission/status/#where_are_they_now |title=Voyager Mission Status |publisher=JPL |access-date=10 February 2022 |archive-date=1 January 2018 |archive-url=https://web.archive.org/web/20180101025244/https://voyager.jpl.nasa.gov/mission/status/#where_are_they_now |url-status=live }}</ref> reaching a distance of {{Convert|162|AU|e9km e9mi|sigfig=3|abbr=unit|lk=on}} from Earth as of May 25, 2024.<ref name="voyager">{{cite web |url=https://voyager.jpl.nasa.gov/mission/status/ |title=Voyager – Mission Status |work=[[Jet Propulsion Laboratory]] |publisher=[[National Aeronautics and Space Administration]] |access-date=April 24, 2021 |archive-date=1 January 2018 |archive-url=https://web.archive.org/web/20180101025244/https://voyager.jpl.nasa.gov/mission/status/ |url-status=live }}</ref> {{as of|2024}}, ''Voyager 2'' is moving with a velocity of {{convert|55,347|km/h|sp=us}}, or 15&nbsp;km/s, relative to the Sun, and is {{convert|20,439,100,000|km|sp=us}} from the Sun<ref name="JPL.Voyager2">{{cite web|url=https://solarsystem.nasa.gov/missions/voyager-2/in-depth/|title=In Depth – Voyager 2|publisher=JPL|access-date=10 February 2022|archive-date=20 April 2017|archive-url=https://web.archive.org/web/20170420085656/https://solarsystem.nasa.gov/missions/voyager2/indepth|url-status=live}}</ref> reaching a distance of {{Convert|136.627|AU|e9km e9mi|sigfig=3|abbr=unit|lk=on}} from Earth as of May 25, 2024.<ref name="voyager" /> 

The two Voyagers are the only human-made objects to date that have passed into interstellar space — a record they will hold until at least the 2040s — and ''Voyager 1'' is the farthest human-made object from Earth.<ref name=":0" />