Timeline of New Horizons explained

See main article: New Horizons. Timeline for the New Horizons interplanetary space probe lists the significant events of the launch, transition phases as well as subsequent significant operational mission events; by date and brief description.

Preparation phase

• January 8, 2001: Proposal team meets face-to-face for the first time at the Johns Hopkins University Applied Physics Laboratory.^[1]
• February 5, 2001: New Horizons name chosen.^{[1] [2]}
• April 6, 2001: New Horizons proposal submitted to NASA. It was one of five proposals submitted, which were later narrowed to two for Phase A study: POSSE (Pluto and Outer Solar System Explorer) and New Horizons.^[1]
• November 29, 2001: New Horizons proposal selected by NASA. Started Phase B study.^[3]
• March 2002: Budget zeroed by Bush administration, later overridden.^{[4] [5]}
• June 13, 2005: Spacecraft departed Applied Physics Laboratory for final testing. It undergoes final testing at Goddard Space Flight Center (GSFC).^[6]
• September 24, 2005: Spacecraft shipped to Cape Canaveral. It was moved through Andrews Air Force Base aboard a C-17 Globemaster III cargo aircraft.^[7]
• December 17, 2005: Spacecraft ready for in rocket positioning. Transported from Hazardous Servicing Facility to Vertical Integration Facility at Space Launch Complex 41.^[8]
• January 11, 2006: Primary launch window opened. The launch was delayed for further testing.^[9]
• January 16, 2006: Rocket moved onto launch pad. Atlas V launcher, serial number AV-010, rolled out onto pad.^[10]
• January 17, 2006: Launch delayed. First day launch attempts scrubbed because of unacceptable weather conditions (high winds).^{[11] [12]}
• January 18, 2006: Launch delayed again. Second launch attempt scrubbed because of morning power outage at the Applied Physics Laboratory.^[13]

Launch phase

• January 19, 2006: Successful launch at 19:00 UTC after a brief delay due to cloud cover.^{[14] [15]}

Jupiter pre-encounter phase

• April 7, 2006: The probe passed Mars' orbit 1.5 AU from Earth.^{[16] [17]}
• June 13, 2006: Flyby of asteroid 132524 APL. The probe passed closest to the asteroid 132524 APL in the Asteroid Belt at about 101,867 km at 04:05 UTC. Pictures were taken.^[18]
• November 28, 2006: First image of Pluto. The image of Pluto was taken from a great distance.^[19]

Jupiter encounter phase

• January 10, 2007: Navigation exercise near Jupiter. Long-distance observations of Jupiter's outer moon Callirrhoe as a navigation exercise.^[20]
• February 28, 2007: Jupiter flyby. Closest approach occurred at 05:43:40 UTC at 2.305 million km, 21.219 km/s.^[21]

Pluto pre-encounter phase

• June 8, 2008: The probe passed Saturn's orbit 9.5 AU from Earth.^{[21] [22]}
• December 29, 2009: The probe becomes closer to Pluto than to Earth. Pluto was then 32.7 AU from Earth, and the probe was 16.4 AU from Earth.^{[23] [24] [25]}
• February 25, 2010: New Horizons completed 1.48order=flipNaNorder=flip, half the total travel distance of 2.96order=flipNaNorder=flip.^[26]
• March 18, 2011: The probe passes Uranus' orbit. This is the fourth planetary orbit the spacecraft crossed since its start. New Horizons reached Uranus's orbit at 22:00 UTC.^{[27] [28]}
• December 2, 2011: New Horizons draws closer to Pluto than any other spacecraft has ever been. Previously, Voyager 1 held the record for the closest approach. (~10.58 AU)^[29]
• February 11, 2012: New Horizons reaches the distance of 10 AU from the Pluto system, at around 4:55 UTC.^[30]
• July 1, 2013: New Horizons captures its first image of Charon. Charon is clearly separated from Pluto using the Long-Range Reconnaissance Imager (LORRI).^{[31] [32]}
• October 25, 2013: New Horizons reaches the distance of 5 AU from the Pluto system.^[33]
• July 10, 2014: Photos of Neptune and Triton from about 4 billion km away.^[34]
• July 20, 2014: Photos of Pluto and Charon. Images obtained showing both bodies orbiting each other, distance 2.8 AU.^[35]
• August 25, 2014: The probe passes Neptune's orbit. This was the fifth planetary orbit crossed.^[36]
• December 7, 2014: New Horizons awakes from hibernation. NASA's Deep Sky Network station at Tidbinbilla, Australia received a signal confirming that it successfully awoke from hibernation.^{[37] [38] [39]}
• January 2015: Observation of Kuiper belt object . Distant observations from a distance of roughly 75 million km (~0.5 AU)^[40]
• January 15, 2015: Start of Pluto observations. New Horizons is now close enough to Pluto and begins observing the system.^{[41] [42]}
• March 10–11, 2015: New Horizons reaches a distance of 1 AU from the Pluto system.^[43]
• March 20, 2015: NASA invites the general public to suggest names for surface features that may be discovered on Pluto and Charon.^[44]
• May 15, 2015: Images exceed best Hubble Space Telescope resolution.

Pluto science phase

• July 14, 2015: Flyby of the Pluto system: Pluto, Charon, Hydra, Nix, Kerberos and Styx.
  Flyby of Pluto around 11:49:57 UTC at 12,500 km, 13.78 km/s.
  Pluto is 32.9 AU from Sun.
  Flyby of Charon around 12:03:50 UTC at 28,858 km, 13.87 km/s.^[45]
• July 14, 2015 to October 25, 2016: Transmission of collected data sent back to Earth, and ongoing science discovery based on the observations. The bit rate of the downlink is limited to 1–2 kb/s,^[46] so it took until October 25, 2016, to transmit all the data.^{[47] [48] [49] [50]}

Arrokoth pre-encounter phase

• October 22 – November 4, 2015: Trajectory correction maneuver. A course adjustment for the January 2019 flyby of Arrokoth was performed in a series of four thruster firings of 22 minutes each.^{[51] [52]}
• November 2, 2015: Observation of KBO 15810 Arawn. Long-range observations from a distance of 274e6km, the closest ever for any Trans-Neptunian Object other than Pluto and 486958 Arrokoth. More images were taken on April 7–8, 2016, at a range of 179e6km as well.^[53]
• July 13–14, 2016: Observation of KBO 50000 Quaoar. Long-range observations from a distance of 2.1e9km gives mission scientists a different perspective in order to study the light-scattering properties of Quaoar's surface.^[54]
• February 1, 2017: Trajectory correction maneuver. A small course adjustment towards the January 2019 flyby of Arrokoth was performed with a 44-second thruster firing.^[55]
• March 12, 2017: Arrokoth's orbit is deemed to be sufficiently well-resolved that it is formally catalogued as minor planet #486,958 and announced as such via Minor Planet Circular 103886.^[56] From now until its naming in November 2019, the object's official designation is to be .
• 2017–2020: Observations of Kuiper belt objects (KBOs). The probe will have opportunities to perform observations of 10 to 20 KBOs visible from the spacecraft's trajectory after the Pluto system flyby. Heliosphere data collection is expected to begin.^{[57] [58] [59]}
• December 9, 2017: Trajectory correction maneuver. This delays the arrival at Arrokoth by a few hours, optimizing coverage by ground-based radio telescopes.^{[60] [61]}
• December 23, 2017 – June 4, 2018: Final hibernation period before the (KBO) Arrokoth encounter.^[62]
• August 2018 – March 2019: Distant observations of at least a dozen distant KBOs. Recovered by Subaru Telescope in 2014–2017, enabling New Horizons observations^[63]
• August 13, 2018: Switch from spin stabilization to 3-axis stabilization.
• August 16, 2018 – December 24, 2018: Approach phase. Optical navigation, search for hazardous material around Arrokoth
• August 16, 2018: First detection of Kuiper belt object Arrokoth^[64]
• October 4, 2018 – December 2, 2018: Opportunities for trajectory correction maneuvers. Maneuvers scheduled for October 4 and November 20, with backups on October 23 and December 2, respectively

Arrokoth science phase and beyond

• January 1, 2019: Flyby of Arrokoth, then nicknamed Ultima Thule. The flyby occurred at 05:33 UTC, and is the outermost close encounter of any Solar System object.^[65]
• January 9, 2019: Switch from 3-axis stabilization to spin stabilization. This ended the Arrokoth flyby, marking the beginning of the downlink phase.
• 2019–2020: Downlink of data from the Arrokoth flyby. Predicted to take approximately 20 months.
• November 12, 2019: The object previously known by the provisional designation of (later numbered 486958 and nicknamed Ultima Thule) was officially named Arrokoth.^[66]
• April 22–23, 2020: Stellar distance measurements to both Proxima Centauri, and Wolf 359 using stereoscopic images from New Horizons and Earth-based telescopes for usable parallax observation.^[67]
• April 15, 2021: New Horizons reaches 50 AU from the Sun, becoming the fifth spacecraft to reach the milestone.^[68]
• April 30, 2021: End of the first extended mission.
• May 26, 2022: "NASA’s New Horizons mission’s second extended mission proposal was approved." This two-year mission "will make distant observations of Uranus and Neptune[,] map the very faint 'cosmic background' in visible and ultraviolet (UV) light [and use] its instruments to understand the motions of charged particles as they interact with the solar wind, and to understand our heliosphere's large-scale structure."^[69]
• 2020s: The probe may be able to fly by a third KBO. The probe approached Arrokoth along its rotational axis, which simplified trajectory correction maneuvers, saving fuel that could be used to target another KBO.^{[70] [71]} After the flyby, the spacecraft was left with of fuel.^[72]
• Mid to late 2030s: Expected end of the mission, based on RTG decay. Heliosphere data collection expected to be intermittent if instrument power sharing is required.^{[73] [71]}

Post-mission phase

• 2038: New Horizons will be 100 AU from the Sun. If still functioning, the probe will explore the outer heliosphere and interstellar space along with the Voyager spacecraft.^[74]

Notes and References

1. The New Horizons Pluto Kuiper belt Mission: An Overview with Historical Context . Space Science Reviews . 140 . 1–4 . 3–21 . Stern . Alan . 2008 . May 20, 2015 . https://web.archive.org/web/20150923194028/http://www.boulder.swri.edu/pkb/ssr/ssr-intro.pdf . September 23, 2015. live . 2008SSRv..140....3S . 0709.4417 . 10.1007/s11214-007-9295-y . 119197398 .
2. News: New Horizons indeed . The Space Review . S. Alan . Stern . May 9, 2005.
3. Web site: NASA Selects Pluto-Kuiper Belt Mission For Phase B Study . NASA . Savage . D. . November 29, 2001 . January 12, 2011 . https://web.archive.org/web/20110308190424/http://nssdc.gsfc.nasa.gov/planetary/text/pluto_pr_20011129.txt . live . March 8, 2011.
4. Web site: Cuts threaten mission to Pluto . 4 March 2002 . May 13, 2015 . June 7, 2015 . https://web.archive.org/web/20150607020128/http://articles.baltimoresun.com/2002-03-04/news/0203040036_1_study-pluto-pluto-mission-apl . live .
5. Web site: The Planetary Society . May 13, 2015.
6. APL-Built Pluto Spacecraft Begins Launch Preparations . Johns Hopkins University Applied Physics Laboratory . Michael . Buckley . Dwayne . Brown . George . Diller . September 26, 2005 . August 30, 2014 . https://web.archive.org/web/20150115020755/http://www.jhuapl.edu/newscenter/pressreleases/2005/050926.asp . January 15, 2015 . dead .
7. Web site: NASA'S Pluto Space Probe Begins Launch Preparations . SpaceDaily . September 27, 2005 . January 12, 2011 . https://web.archive.org/web/20091231125211/http://www.spacedaily.com/reports/NASAS_Pluto_Space_Probe_Begins_Launch_Preparations.html . December 31, 2009 . dead .
8. News: NASA Met Unprecedented Challenges Sending Spacecraft to Pluto . Granath . Bob . June 30, 2015 . NASA . May 1, 2018 . en.
9. Web site: Leonard . David . New Horizons Pluto Probe Readied For Launch . . September 1, 2005.
10. Web site: Cooper . Ben . New Horizons Rollout . January 2006 . Launch Photography . July 5, 2015 . August 4, 2020 . https://web.archive.org/web/20200804170818/http://www.launchphotography.com/NewHorizonsRollout.html . dead .
11. News: Winds Delay Launching for NASA Mission to Pluto . The New York Times . Warren E. . Leary . January 17, 2006.
12. Web site: Launch of NASA's Pluto Probe Delayed for 24 Hours . Space.com . January 17, 2006 . June 3, 2013.
13. Web site: Malik . Tariq . Power Outage Delays Launch of NASA's Pluto Probe . Space.com . January 18, 2006 . May 12, 2015.
14. Web site: New Horizons Launched on its Way to Pluto . The Planetary Society . Amir . Alexander . January 19, 2006 . https://web.archive.org/web/20120318214956/http://www.planetary.org/news/2006/0119_New_Horizons_Launched_on_its_Way_to.html . March 18, 2012.
15. News: New Horizons launches on voyage to Pluto and beyond . Spaceflight Now . Harwood . William . January 19, 2006 . January 12, 2011 . https://web.archive.org/web/20101130001152/http://spaceflightnow.com/atlas/av010/060119launch.html . November 30, 2010 . live.
16. News: Malik . T. . Pluto-Bound Probe Passes Mars' Orbit . Space.com . April 7, 2006 . January 14, 2011 . https://web.archive.org/web/20111127062040/http://www.space.com/2263-pluto-bound-probe-passes-mars-orbit.html . November 27, 2011 . dead .
17. Web site: mars 7 april 2006 – Wolfram|Alpha. www.wolframalpha.com.
18. The New Horizons Distant Flyby of Asteroid 2002 JF56 . Bulletin of the American Astronomical Society . Catherine B. . Olkin . 38 . 597 . 2006DPS....38.5922O . 4 . Reuter . Lunsford . Binzel . Stern . 2006.
19. Web site: K. Beisser . New Horizons, Not Quite to Jupiter, Makes First Pluto Sighting . JHU/APL . November 28, 2006 . January 13, 2011 . https://web.archive.org/web/20141113224846/http://pluto.jhuapl.edu/news_center/news/112806.php . November 13, 2014 . dead .
20. Web site: New Horizons Jupiter Encounter Timeline . The Planetary Society . October 24, 2014.
21. Web site: Mission Timeline . Johns Hopkins APL . August 1, 2012 . dead . https://web.archive.org/web/20080723174449/http://www.pluto.jhuapl.edu/mission/mission_timeline.php . July 23, 2008.
22. Web site: Distance between Saturn and Earth on June 8, 2008 . March 14, 2011.
23. Web site: Villard . R. . New Horizons Crosses Halfway Point to Pluto . Discovery Communications, LLC. . December 29, 2009 . January 12, 2011 . https://web.archive.org/web/20101225175153/http://news.discovery.com/space/new-horizons-crosses-halfway-point-to-pluto.html . December 25, 2010 . dead .
24. Web site: Distance between Pluto and Earth on December 29, 2009 . March 14, 2011.
25. Web site: New Horizon properties on December 29, 2009 . March 14, 2011.
26. News: Spacecraft Hits Midpoint on Flight to Pluto . Space.com . February 26, 2010 . August 11, 2011.
27. Web site: Space Spin – New Horizons ventures beyond Saturn's orbit . June 9, 2008 . March 14, 2011 . dead . https://web.archive.org/web/20110723084517/http://spacespin.org/article.php/80636-new-horizons-beyond-saturn-orbit . July 23, 2011 .
28. Web site: NASA Pluto Probe Passes Orbit of Uranus . March 18, 2011 . March 19, 2011 . SPACE.com . SPACE.com Staff.
29. Web site: Twitter.com – NewHorizons2015.
30. Web site: New Horizons on Approach: 22 AU Down, Just 10 to Go . JHU/APL . February 10, 2012 . March 22, 2012 . dead . https://web.archive.org/web/20141113224823/http://pluto.jhuapl.edu/news_center/news/20120210.php . November 13, 2014 .
31. News: New Horizons Gets a First Glimpse of Pluto's Moon Charon . Phil . Plait . July 11, 2013 . Slate.
32. Web site: Charon Revealed! New Horizons Camera Spots Pluto's Largest Moon . July 10, 2013 . New Horizons; Headlines . . dead . https://web.archive.org/web/20131208200701/http://pluto.jhuapl.edu/news_center/news/20130710.php . December 8, 2013 .
33. Web site: On the Path to Pluto, 5 AU and Closing . October 25, 2013 . New Horizons; Headlines . . dead . https://web.archive.org/web/20141113224829/http://pluto.jhuapl.edu/news_center/news/20131025.php . November 13, 2014 .
34. Web site: NASA's New Horizons probe crosses orbit of Neptune 25 years after Voyager 2 | collectSPACE.
35. Web site: New Horizons Spies Charon Orbiting Pluto . Johns Hopkins APL . dead . https://web.archive.org/web/20140808090015/http://pluto.jhuapl.edu/news_center/news/20140807.php . August 8, 2014 .
36. Web site: Passing the Planets . Johns Hopkins APL . March 18, 2011 . April 3, 2012 . dead . https://web.archive.org/web/20140714214438/http://pluto.jhuapl.edu/mission/passingplanets/passingPlanets_current.php . July 14, 2014 .
37. Web site: NASA New Horizons (@NASANewHorizons) – Twitter.
38. News: It's Alive! NASA's New Horizons Pluto Probe 'Wakes Up' for Work . NBC News . December 6, 2014.
39. Nally . Jonathan . Ready for a Close Encounter . Australian Sky & Telescope . 83 . 14 . 1832-0457.
40. Web site: NewHorizons2015 . About the Jan 21o5 KBO, It's VNH0004 . August 21, 2012. Web site: Buie . Marc W. . Orbit Fit and Astrometric record for VNH0004 . User pages . Southwest Research Institute Planetary Science Directorate . August 21, 2012.
41. Web site: Brown . Dwayne . Buckley . Michael . Stothoff . Maria . January 15, 2015 Release 15-011 – NASA's New Horizons Spacecraft Begins First Stages of Pluto Encounter . January 15, 2015 . . January 15, 2015 . April 7, 2020 . https://web.archive.org/web/20200407083332/https://www.nasa.gov/press/2015/january/nasa-s-new-horizons-spacecraft-begins-first-stages-of-pluto-encounter . live .
42. Web site: New Frontier News . December 6, 2014 . January 8, 2015 . dead . https://web.archive.org/web/20150108160447/http://discoverynewfrontiers.nasa.gov/news/index.cfml?ID=33 . January 8, 2015 .
43. Web site: New Horizons . jhuapl.edu . July 13, 2015.
44. Web site: pluto-update . ourpluto.org . July 13, 2015 . https://web.archive.org/web/20160423054711/http://www.ourpluto.org/ . April 23, 2016 . dead .
45. Web site: New Horizons Pluto Flyby Press Kit . July 2, 2015 . July 4, 2015.
46. Web site: How exactly does New Horizons send all that data back from Pluto? . The Hub . Johns Hopkins University . Greg . Rienzi . July 17, 2015 . July 17, 2015.
47. News: No More Data From Pluto . . Chang . Kenneth . October 28, 2016 . October 28, 2016 . March 29, 2019 . https://web.archive.org/web/20190329002642/https://www.nytimes.com/2016/10/29/science/pluto-nasa-new-horizons.html . live .
48. News: New Horizons begins massive 'treasure trove' data downlink . Gizmag . David . Szondy . September 7, 2015 . February 28, 2016.
49. Web site: Pretty Pictures: Downlink of the Full New Horizons Data Set Has Begun . The Planetary Society . Emily . Lakdawalla . September 10, 2015 . February 28, 2016.
50. Web site: New Pluto Images from NASA's New Horizons: It's Complicated . . Tricia . Talbert . September 10, 2015 . February 28, 2016.
51. News: How NASA Is Steering New Horizons Toward a Tiny Space Rock in the Kuiper Belt . . Nick . Stockton . November 4, 2015 . May 30, 2017.
52. News: New Horizons prepares for New Year's Day 2019 Kuiper Belt Object encounter . . Chris . Gebhardt . January 3, 2017 . May 30, 2017.
53. Web site: A Distant Close-up: New Horizons' Camera Captures a Wandering Kuiper Belt Object . New Horizons . NASA/JHUAPL . December 4, 2015 . July 23, 2016.
54. Web site: Tricia . Talbert . New Horizons Spies a Kuiper Belt Companion . . en-US . August 31, 2016 . July 16, 2017.
55. Web site: New Horizons Refines Course for Next Flyby . . Tricia . Talbert . February 1, 2017 . May 30, 2017.
56. Web site: Minor Planet Center. Minor Planet Circular 103886. March 12, 2017 .
57. News: New Horizons extended mission target selected . . Lakdawalla . Emily . Emily Lakdawalla . September 1, 2015 . September 22, 2015 . October 18, 2015 . https://web.archive.org/web/20151018200350/http://www.planetary.org/blogs/emily-lakdawalla/2015/09011608-new-horizons-extended-mission-pt1.html . live .
58. Web site: Stern . Alan . Alan Stern . OPAG: We Did It! . . . August 2015 . 32, 35 . September 30, 2015 . September 7, 2015 . https://web.archive.org/web/20150907000920/http://www.lpi.usra.edu/opag/meetings/aug2015/presentations/day-2/13_stern.pdf . live .
59. Web site: Why Go to Pluto? . Johns Hopkins APL . December 5, 2015.
60. Web site: Lakdawalla . Emily . New Horizons prepares for encounter with 2014 MU69 . Planetary Society . January 24, 2018 . January 26, 2018 . February 20, 2018 . https://web.archive.org/web/20180220213605/http://www.planetary.org/blogs/emily-lakdawalla/2018/0124-new-horizons-prepares-for-2014mu69.html . live .
61. Web site: New Horizons Corrects Its Course in the Kuiper Belt . December 9, 2017 .
62. News: New Horizons put in final hibernation before 2019 KBO flyby . Spaceflight Insider . Laurel . Kornfeld . December 24, 2017 . January 11, 2018.
63. Constraints on the Shapes and Rotational States of the Distant New Horizons Kuiper Belt Targets . https://ghostarchive.org/varchive/youtube/20211221/KqOfJ6p1JmQ . 2021-12-21 . live. AGU Fall Meeting. December 11–15, 2017. New Orleans, Louisiana. . Simon . Porter . Anne . Verbiscer . John . Spencer . Harold . Weaver . Marc . Buie . Susan . Benecchi . Catherine . Olkin . Alan . Stern . 1 . 1:22:55–1:36:00 . December 11, 2017 . P13F-07.
64. Web site: Ultima in View: NASA's New Horizons Makes First Detection of Kuiper Belt Flyby Target. August 28, 2018. August 28, 2018. NASA. January 24, 2020. https://web.archive.org/web/20200124212405/https://www.nasa.gov/feature/ultima-in-view-nasa-s-new-horizons-makes-first-detection-of-kuiper-belt-flyby-target/. live.
65. News: Plot thickens as New Horizons moves within year of next flyby . Spaceflight Now . Stephen . Clark . January 6, 2018 . January 11, 2018.
66. Web site: New Horizons Kuiper Belt Flyby Object Officially Named 'Arrokoth' . . pluto.jhuapl.edu . November 12, 2019 . November 14, 2019 . January 2, 2020 . https://web.archive.org/web/20200102130243/http://pluto.jhuapl.edu/News-Center/News-Article.php?page=20191112.
67. Nature Davide Castelvecchi (11 June 2020) Pluto probe offers eye-popping view of neighbouring star Proxima Centauri doi: 10.1038/d41586-020-01699-6
68. Web site: NASA's New Horizons probe reaches rare distance, looks out to farthest Voyager collectSPACE . collectSPACE.com.
69. Web site: Talbert . Tricia . 2022-04-25 . Update: NASA Extends Exploration for 8 Planetary Science Missions . 2022-07-03 . NASA.
70. Web site: Stephen . Clark . Scientists firm up flyby plan for New Horizons's next destination . Spaceflight Now . September 21, 2017.
71. Web site: Wall . Mike . New Horizons May Make Yet Another Flyby After Ultima Thule. . December 21, 2018.
72. https://www.bbc.com/news/science-environment-46699737 New Horizons: Nasa waits for signal from Ultima Thule probe
73. Web site: NASA . New Horizons . NASA Solar System Exploration . National Aeronautics and Space Administration . February 21, 2012 . July 20, 2011 . dead . https://web.archive.org/web/20031026205743/http://sse.jpl.nasa.gov/missions/profile.cfm?Sort=Chron . October 26, 2003 .
74. Web site: New Horizons Salutes Voyager. August 17, 2006. Johns Hopkins APL. https://web.archive.org/web/20141113224847/http://pluto.jhuapl.edu/news_center/news/081706.php. November 13, 2014. dead. November 3, 2009.