A 1766 Benjamin Martin mechanical model, or orrery, on display at the Harvard Collection of Historical Scientific Instruments

Solar System models, especially mechanical models, called orreries, that illustrate the relative positions and motions of the planets and moons in the Solar System have been built for centuries. While they often showed relative sizes, these models were usually not built to scale. The enormous ratio of interplanetary distances to planetary diameters makes constructing a scale model of the Solar System a challenging task. As one example of the difficulty, the distance between the Earth and the Sun is almost 12,000 times the diameter of the Earth.

If the smaller planets are to be easily visible to the naked eye, large outdoor spaces are generally necessary, as is some means for highlighting objects that might otherwise not be noticed from a distance. The Boston Museum of Science had placed bronze models of the planets in major public buildings, all on similar stands with interpretive labels.[1] For example, the model of Jupiter was located in the cavernous South Station waiting area. The properly-scaled, basket-ball-sized model is 1.3 miles (2.14 km) from the model Sun which is located at the museum, graphically illustrating the immense empty space in the Solar System.

The objects in such large models do not move. Traditional orreries often did move, and some used clockworks to display the relative speeds of objects accurately. These can be thought of as being correctly scaled in time, instead of distance.

Permanent true scale models

Many towns and institutions have built outdoor scale models of the Solar System. Here is a table comparing these models with the actual system.

Name Location Scale:
1 : …
Sun dia. Earth dia. Sun–Earth Sun–Pluto Description
Actual Solar System 1 1.392 Gm 12.76 Mm 149.6 Gm 5.914 Tm
Sweden Solar System[2]  Sweden 20,000,000 71 m 65 cm 7,600 m 300 km permanent; country-wide (begun 1998)
Solar System Drive[3][4] Australia Coonabarabran, Australia 38,000,000 37 m 34 cm 4,100 m 205 km permanent; drivable (est. 1997)
Maine Solar System[5][6] United States University of Maine 93,000,000 15 m 13.7 cm 1,600 m 64 km permanent; drivable (est.2003)
Mont Megantic Dark Sky Reserve Great Solar System Canada Parc national du Mont-Mégantic 100,000,000 14 m 12.4 cm 1,450 m 57 km permanent; drivable (est.2018)
Otago Central Interplanetary Cycle Trail[7][8][9] New Zealand Otago Central Rail Trail 100,000,000 13.91 m 12 cm 1,496 m 59.06 km permanent; cyclable (est.2017)
Riverfront Museum Solar System[10][11][12][13] United States Peoria, Illinois 99,000,000 11 m 10.0 cm 1,200 m 47 km permanent; drivable (est. 1992?)
Vienna Solar System Austria Vienna, Austria 163,764,706 8.5 m 7.78 cm 913 m 36 km under construction since 2018. Physical + Augmented Reality
Planet Lofoten Norway Lofoten, Norway 200,000,000 7 m ? ? 30 km under construction
Planet Trek Dane County United States Madison, Wisconsin 200,000,000 7 m 6.6 cm 777 m 38.3 km permanent; fully accessible by foot and bike paths (est. 2009)
Sunspot Solar System Model[14][15][16][17] United States Sunspot, New Mexico 250,000,000 5.6 m 5.1 cm 1.5 m 23.6 km permanent, drivable
Lethbridge Solar System Model Canada Lethbridge, Alberta, Canada 254,000,000 5.5 m 5 cm 500 m 14.7 km (Neptune) permanent, drivable, walkable (est. 2022)
El Sistema Solar de la comarca de Ciudad Rodrigo Spain Ciudad Rodrigo, Spain 290,000,000 4.8 m 4.4 cm 1.2 m 25 km permanent, Walk & Drive
If the Earth were a Ping-Pong ball[citation needed] United Kingdom Westminster, London 318,905,000 4.36 m 4 cm ? ? In construction; Walk & Drive (est. 2018) Centered around Deans Yard, Westminster
Light Speed Planet Walk[18] United States Anchorage, Alaska 350,000,000 ? ? ? 16.6 km permanent; drivable (est. 2005)
Moab's Scale Model of the Solar System[19] United States Moab, Utah 400,000,000 3.6 m 2.4 cm ? 15.3 km permanent; Walk and Drive (est. 2007)
Community Solar System Trail[20][21] United States Boston, Massachusetts 400,000,000 3.5 m 3.2 cm 380 m 15.3 km permanent; drivable (established in 1997, removed in 2015)
The Solar System to Scale Portugal Estremoz, Portugal 414,000,000 3.4 m 3.1 cm 361 m 14.3 km permanent; drivable; bikeable
Solar System Stroll[22] Slovakia Bratislava, Slovakia 464,000,000 3 m 2.7 cm 322 m 13 km permanent; bikeable, drivable; under construction since 2024
Somerset Space Walk United Kingdom Bridgwater Canal, Somerset UK 530,000,000 2.5 m ? ? 11 km permanent; bikeable (est. 1997)
York’s Solar System model United Kingdom York, England 575,872,239 2.4 m 2.2 cm 260 m 10.3 km permanent; bikeable (est. 1999)
Traverse Bay Community Solar System[23] United States Traverse City, Michigan 592,763,356 0.9 m ? 209 m 10.0 km permanent; bikeable (est. 2004)
Michigan Solar System Model[24] United States Coleman, Michigan 608,000,000 2.3 m 2.1 cm 324 m 9.8 km permanent; bike trail Sun and Pls. Spheres (2017)
Solar System Czech Republic Opava, Czech Republic 627,000,000 2.2 m 2.0 cm 239 m 9.42 km permanent; bikeable; walkable; drivable (est. 2006)
Nine Views Croatia Zagreb, Croatia 680,000,000 2.0 m 1.9 cm 225 m 8.7 km permanent; bikeable (est. 2004)
Walk the Solar System Canada Fort St. John, British Columbia, Canada 682,353,000 2.0 m 1.9 cm 219 m 8.6 km under construction
McCarthy Observatory[25] United States New Milford, Connecticut 761,155,000 1.8 m 1.7 cm 195 m 7.1 km permanent; bikeable (est. 2009)
Planet Walk[26] United States Glen Burnie, Maryland. 781,000,000 ? ? 191.5 m 7.56 km Walkable, bikeable (est. 2008). Part of the permanent Baltimore & Annapolis Trail.
Trilho do Sistema Solar Portugal Paredes de Coura, Portugal 831,000,000 1.675 m 1.533 cm 180 m 5.42 km (Neptune) permanent; walkable; bikeable (est. 2016)
Planetenpad Utrecht Netherlands Utrecht, The Netherlands 1,000,000,000 1.3 m 1.3 cm 150 m 7.4 km (Neptune) Leads from Centre Utrecht to Rhijnauwen, on foot, on bike or on kayak
Model of the Solar System Finland Helsinki, Finland 1,000,000,000 1.4 m 1.2 cm 149.6 m 6.1 km permanent; bikeable
Planetenmodell Hagen Germany Hagen, Germany 1,000,000,000 1.4 m 1.3 cm 150 m 5.9 km permanent; bikeable (est. 1959)
Planetenweg Schwarzbach Germany Kriftel, Germany 1,000,000,000 1.4 m 1.3 cm 150 m 5.9 km permanent; bikeable (est. 1998)
Uetliberg Planetenweg Switzerland Zürich, Switzerland 1,000,000,000 1.4 m 1.3 cm 150 m 5.9 km permanent; bikeable
Planetenwanderweg Germany Ehrenfriedersdorf, Germany 1,000,000,000 1.4 m 1.3 cm 150 m 5.9 km permanent; bikeable
Planetary Trail Czech Republic Hradec Králové, Czech Republic 1,000,000,000 1.4 m 1.3 cm 150 m 5.9 km permanent; bikeable (est. 2005)
Planetary Trail Czech Republic Prague, Czech Republic 1,000,000,000 1.4 m 1.3 cm 150 m 13 km (Sedna as discovered)
5.9 km (Pluto)
permanent; bike & walk; all objects above 1000km; (est. 13.5.2018)
Melbourne Solar System[27][28] Australia Melbourne, Australia 1,000,000,000 1.4 m 1.3 cm 150 m 5.9 km (Pluto)
40 140 km (Proxima Centauri)
permanent; bikeable (est. 2008) Proxima Centauri scale distance calculated travelling Melbourne to Melbourne via the Poles.[29]
Scale Model Solar System[30] United States Eugene, Oregon 1,000,000,000 1.4 m 1.2 cm 150 m 5.9 km permanent; bikeable (est. 1997)
Planetstien, Sandnes Norway Sandnes, Norway 1,000,000,000 1.4 m 1.2 cm 150 m 5.9 km permanent; walkable, bikeable (est. 2010)
Planetstien, Lemvig Denmark Lemvig, Denmark 1,000,000,000 1.4 m 1.2 cm 150 m 5.9 km permanent; walkable
Grand Trunk Pathway Solar System Model Canada Terrace, British Columbia 1,000,000,000 1.4 m 1.3 cm 150 m 6 km permanent; walkable/bikeable (est. 2018)
Planet Walk Germany Munich, Germany 1,290,000,000 1.1 m 1.0 cm 116 m 4.6 km permanent; walkable (est. 1995)
Strolling at the speed of light Canada La Malbaie, Quebec, Canada 1,500,000,000 0.9 m 0.8 cm 100 m 3 km (Neptune) permanent; walkable (est. 2009) (temp?)
State of the Solar System[31][32][33] United States Bellingham, Washington 1,826,770,000 0.762 m 0.6858 cm 82 m ? permanent; walkable (est. 2016)
Meteoria Söderfjärden Finland Vaasa, Finland 2,000,000,000 0.7 m ? ? ? permanent; walkable
Planetenweg Göttingen Germany Göttingen, Germany 2,000,000,000 0.70 m 0.65 cm 75 m 3.2 km permanent; walkable/bikeable (est. 2013)
Solar System Walking Tour[34][35][36] United States Gainesville, Georgia 2,000,000,000 0.7 m 0.6 cm 75 m 2.9 km permanent; walkable (est. 2000)
Rymdpromenaden ("Spacewalk") Sweden Gothenburg, Sweden 2,000,000,000 0.7 m 0.6 cm 75 m 3 km permanent; walkable (est. 1978)
Montshire Museum of Science[37] United States Norwich, Vermont 2,200,000,000 0.6 m 0.6 cm 68 m 2.7 km permanent; walkable
Ride to Pluto: Boise's Solar System[38] United States Boise Greenbelt, Boise, Idaho 2,200,000,000 0.5 m ? ? 2.4 km permanent; walkable & bikeable
The Solar walk[39][40] United States Longview, Washington 2,240,000,000 0.6 m 0.6 cm 56.94 m 2.7 km permanent; walkable (est. 2001)
Akaa Solar System Scale Model Finland Akaa, Finland 3,000,000,000 0.46 m 0.4 cm 49.9 m 1.958 km (Pluto)
13 370 km (Proxima Centauri)
permanent; walkable (est. 2017), Proxima Centauri in Yulara, Australia
Elmhurst Scale Model of the Solar System[41][42] United States Elmhurst, Illinois 3,044,620,000 0.5 m 0.4 cm 49.1 m 1.929 km permanent; walk & drive (est. 2013)
Solar System model group of sculptures Hungary Kecskemét, Hungary 3,300,000,000 0.418 m 0.4 cm 45 m 1.8 km permanent; walkable (est. 2002)
Milky Way path Netherlands Westerbork, The Netherlands 3,700,000,000 ? ? ? 2.5 km permanent; walkable
Solar Walk United States Gainesville, Florida 4,000,000,000 0.3 m 0.3 cm 37.4 m 1.5 km permanent; walkable (est. 2002)
Otford Solar System Model [43] United Kingdom Otford, England 4,595,700,000 0.3 m 0.3 cm 32 m 900 m permanent; walkable; Includes: Proxima Centauri in Los Angeles, USA; Barnard’s Star in Port Stanley, Falkland Islands; Sirius in Sydney, Australia; and Ross 154 in Christchurch, New Zealand
Wooster Planet Walk United States Wooster, Ohio 5,000,000,000 0.3 m 0.3 cm 30 m 1.2 km permanent; walkable (est. 2014)
The Sagan Planet Walk United States Ithaca, New York 5,000,000,000 0.3 m 0.3 cm 30 m 1.2 km permanent; walkable (est. 1997)
Delmar Loop Planet Walk United States University City, Missouri 5,000,000,000 0.3 m 0.2 cm 30 m 870 m (Neptune) permanent; walkable (est. 2009)
The Solar Walk United States Cleveland, Ohio 5,280,000,000 0.3 m 0.2 cm 28.4 m 1.1 km permanent; walkable
Solar System Walk

An Exploration of Scale

United States Carlsbad, California 5,280,000,000 ? ? 28 m 1.119 km Located near Lake Calavera
O Sistema Solar no Parque[44] Brazil Natal, Brazil 7,000,000,000 0.2 m 1.8 mm 22 m 875 m permanent; walkable/bikeable (est. June 3rd, 2016)
A True Scale Model of the Solar System[45][46] United States Cookeville, Tennessee 10,000,000,000 0.14 m 0.12 cm 15 m 590 m permanent; walkable (est. 2017)
Voyage National Program United States Boulder, Colorado (2021) Palo Alto, California (2022)[47][48] Broken Arrow, Oklahoma (2022) Ocala, Florida (2022) Calcasieu Parish, Louisiana (2022) Dover, New Hampshire (2023) Spokane, Washington (2022) Memphis, Tennessee (2023) Chalmette, Louisiana (2023) 10,000,000,000 0.1 m 0.1 cm 15 m 600 m permanent; walkable; US national program
Lake Innitou Thousand Yard Interplanetary Walk United States Woburn, Massachusetts 10,000,000,000 0.23 m (bowling ball) N/A (stone plaque) 24 m 932 m (1019 yd) permanent; walkable (est. 2004); along the sidewalk by Horn Pond.
NJ Botanical Garden United States Ringwood, New Jersey 10,000,000,000 0.2 m 2.0 cm 23.8 m 927 m walkable
Colorado Scale Model Solar System United States Fiske Planetarium, Boulder, Colorado 10,000,000,000 0.1 m 0.1 cm 15 m 600 m permanent; walkable (est. 1987)
Anstruther Model Solar System United Kingdom Anstruther, Scotland 10,000,000,000 0.1 m 0.1 cm 15 m 600 m permanent; walkable (est. 2014)
Le Chemin Solaire France La Couyère, Brittany 10,000,000,000 1 m 0.1 cm ? 450 m permanent; walkable (est. 2011)
Solar Walk UofT Scarborough Canada Toronto, Ontario and Eureka, Nunavut 10,000,000,000 0.14 m 0.13 cm 15 m 591 m permanent; walkable/bikeable (est. 2017)
MIT's Infinite Solar System United States Cambridge, Massachusetts 30,000,000,000 4.6 cm 0.43 mm 5.0 m 200 m permanent; walkable (est. 2018); along "Infinite Corridor"
Solar System Lawn Model[49] United States Griffith Observatory, Los Angeles, California 105,000,000,000 1.32 cm 0.12 mm 1.42 m 56 m permanent; walkable; engraved in the front sidewalk

Other models of the Solar System: historic, temporary, virtual, or dual-scale

Name Location Scale Sun dia. Earth dia. Sun-Earth Sun-Pluto Description
Kirkhill model 1776[b] Scotland Scotland 1:778,268,620.8 1.8 m 1.6 cm 197 m - decayed
Planetenpad Utrecht Netherlands Utrecht, Netherlands 1:1,000,000,000 1.3 m 1.3 cm 150 m 7.4 km (Neptune) Leads from Centre Utrecht to Rhijnauwen, on foot, on bike or by kayak
Planet Walk Malta[1] Malta Buġibba, Malta 1:2,956,760,000 (distance) / 695,000,000 (sizes) 2.0 m 1.84 cm 50.60 m 2.0 km (Neptune) Leads from Malta Aquarium west along promenade
Sorghvliet Netherlands The Hague, Netherlands 1:696,000,000 2.0 m 1.8 cm 215 m 6.5 km (Neptune) (temporary)
Sol Chicago[50][51] United States Illinois, Chicago 1:73,660,000 19 m 17.3 cm 2,050 m 61 km (Neptune) (temporary) proposed
Le Chemin des planètes Switzerland Saint-Luc, Switzerland 1:1,000,000,000 1.4 m 1.3 cm 150 m 5.9 km uses two different scales for distance and size
The Madison Planet Stroll[52] United States Madison, Wisconsin 1:4,000,000,000 0.3 m 0.3 cm 37 m 1.5 km (virtual)
Solar System Stroll Australia Perth, Western Australia 1:5,000,000,000 0.3 m 0.3 cm 30 m 1.2 km permanent; walkable (est. 2016)
The Thousand-Yard Model[53][54] (virtual) 1:6,336,000,000 0.2 m 0.2 cm 25 m 1 km The scale of the planets is the same as the scale between them, and the planets are represented by everyday objects; the Earth is a peppercorn, Jupiter is a walnut, and Neptune is a coffee bean.
(dismantled) Canada Saint-Louis-du-Ha! Ha!, Quebec 1:10,000,000,000 0.1 m 0.1 cm 15 m 0.6 km (dismantled) (est. 1985)
Lafayette Walk United States Detroit, Michigan 1:6,336,000,000 23 cm 0.2 cm 25 m 983 m A walking demonstration of (un)imaginable distances. "It's nowhere near Graham's Number."
Planets on the Path United States Chicago, Illinois 1:2,195,000,000 457 m 13.5 miles (2015, temporary)
The Solar System, to scale, for a school yard PDF for printing 1:11,945,400,000 11.6 cm 0.1 cm 12.5 m 492 m PDFs, A4 and 8½″×11″, to be printed, affixed to cards which are affixed to sticks; then to be held by children standing in a school yard. Includes major moons and asteroids.
Naas Virtual Solar System Republic of Ireland Naas, County Kildare 1 : 154,557,330 9 m 82 mm 968 m 29 km (Neptune) In Ireland, this instantly recognisable roadside spherical sculpture is well known, and is used as the model for the Sun. The website[55] maps out the planetary orbits and shows everyday objects to scale the planets (e.g. a golf ball for Mars)
Saskatoon Solar Walk Saskatoon, Saskatchewan 1 : 1,275,600,000 109 cm 1 cm 110 m 4,500 m Personal and public art installation.

Several sets of geocaching caches have been laid out as Solar System models.

See also

References

  1. ^ Power & Light District to Union Station
  2. ^ Possibly the first accurate scale model after the measurement of the astronomical unit in 1769.
  1. ^ "Boston Community Solar System" at Waymarking.com.
  2. ^ "Sweden Solar System |" (in Swedish). Retrieved 2022-09-15.
  3. ^ "Worlds Largest Virtual Solar System Drive". www.visitnsw.com. Retrieved 2022-09-15.
  4. ^ "Coonabarabran: The world's largest solar system drive". www.playingintheworldgame.com. 5 November 2012. Retrieved 2024-02-19.
  5. ^ Bayly, Julia (2021-08-18). "Here's how you can visit the solar system in Maine, no rocket ship required". Bangor Daily News. Retrieved 2022-09-15.
  6. ^ "Maine Solar System Model". Maine Solar System Model. Retrieved 2022-09-15.
  7. ^ Jones, Pam (2017-03-16). "Solar system to scale on Rail Trail". Otago Daily Times Online News. Retrieved 2022-09-15.
  8. ^ Williams, Katarina (2016-11-12). "Otago Central rail trail to become 100 million to one model replica of the Solar System". Stuff. Retrieved 2022-09-15.
  9. ^ "An Interplanetary Ride". Otago Central Rail Trail. Retrieved 2022-09-15.
  10. ^ "Community Solar System Scale Model | Museum & Informal Education Alliance". informal.jpl.nasa.gov. Retrieved 2022-09-15.
  11. ^ Schoenheider, Jon (26 March 2022). "Interplanetary 5K takes runners across the solar system". www.25newsnow.com. Retrieved 2022-09-15.
  12. ^ "Community Solar System". www.peoriariverfrontmuseum.org/. Retrieved 2024-02-19.
  13. ^ "Peoria Scale Model of the Solar System". atlasobscura.com. Retrieved 2024-02-19.
  14. ^ "Sunspot Solar System Model". informal.jpl.nasa.gov. Retrieved 2024-02-19.
  15. ^ "Sunspot Solar System Model". Archived from the original on 2017-04-11. Retrieved 2024-02-19.
  16. ^ "VISITING THE SUNSPOT OBSERVATORY". sunspot.solar. 19 December 2022. Retrieved 2024-02-19.
  17. ^ "An Overview of Sunspot". sunspot.nmsu.edu. Retrieved 2024-02-19.
  18. ^ "Where to start your Planet Walk". anchorageplanetwalk.org. Retrieved 2024-02-19.
  19. ^ "Moab Scale Model Solar System". slideplayer.com. Retrieved 2024-02-19.
  20. ^ "Greater Boston used to have a scale model of the Solar System". medium.com. 15 August 2021. Retrieved 2024-02-19.
  21. ^ "Museum of Science Boston Community Solar System". foursquare.com. Retrieved 2024-02-19.
  22. ^ "Solar System Stroll website". Retrieved 2024-02-28.
  23. ^ "Solar System". traversetrails.org. Retrieved 2024-02-20.
  24. ^ "SOLAR SYSTEM SCULPTURE INSTALLMENT". midlandcountymi.gov. Retrieved 2024-02-20.
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  27. ^ museumoflost (2018-04-05). "The St Kilda Solar System". The Museum of Lost Things. Retrieved 2022-09-15.
  28. ^ "Nick visits the Melbourne Solar System trail, finds six planets, loses Neptune and takes a surprise trip to Proxima Centauri". Observations. Retrieved 2022-09-15.
  29. ^ https://stkildamelbourne.com.au/wp-content/uploads/2015/11/Solar_System_Self_Guided_Trail_web_friendly.pdf
  30. ^ "Outer Planet Map". members.efn.org/. Retrieved 2024-02-19.
  31. ^ "STATE OF THE SOLAR SYSTEM". stateofthesolarsystembham.wordpress.com/. 5 October 2016. Retrieved 2024-02-19.
  32. ^ "State of the Solar System Poster" (PDF). cob.org/. Retrieved 2024-02-19.
  33. ^ "What's the Deal With: The downtown solar system?". www.cascadiadaily.com/. 25 May 2022. Retrieved 2024-02-19.
  34. ^ "WALKING TOUR OF OUR SOLAR SYSTEM". www.exploregeorgia.org. Retrieved 2024-02-19.
  35. ^ "Solar System Walking Tour" (PDF). www.exploregainesville.org. Retrieved 2024-02-19.
  36. ^ "Solar System Walking Tour". www.gainesville.org. Retrieved 2024-02-19.
  37. ^ "Planet Walk (3.0 miles roundtrip)". www.montshire.org/. Retrieved 2024-02-19.
  38. ^ "Greenbelt's little-known Planet Walk shows solar system's scale". www.idahostatesman.com/. Retrieved 2024-02-19.
  39. ^ "Solar System Walk". www.mylongview.com/. Retrieved 2024-02-19.
  40. ^ "SOLAR SYSTEM MAP". www.friendsofgalileo.com/. Retrieved 2024-02-19.
  41. ^ "Elmhurst Residents Can Boldly Go Where No One Has Gone Before". patch.com. 20 November 2013. Retrieved 2024-02-20.
  42. ^ "ELMHURST SOLAR SYSTEM MODEL". Archived from the original on 2016-03-05. Retrieved 2024-02-20.
  43. ^ "UNESCO Astronomy and World Heritage Webportal - Places connected to the Sky".
  44. ^ "O Sistema Solar no Parque" (in Portuguese). Archived from the original on 2023-12-03. Retrieved 2024-02-19.
  45. ^ "A True Scale Model of the Solar System". www2.tntech.edu. Retrieved 2024-02-20.
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  48. ^ Bennett, J. (2020-01-01). "Voyage Mark II — Scale Model Solar Systems at Moderate Prices". American Astronomical Society Meeting Abstracts #235. 235: 239.06. Bibcode:2020AAS...23523906B.
  49. ^ "Solar System Lawn Model". griffithobservatory.org. Retrieved 2023-05-29.
  50. ^ "Sol Chicago". Archived from the original on 2011-06-25. Retrieved 2024-02-19.
  51. ^ "Sol Chicago". youtube.com/. Retrieved 2024-02-19.
  52. ^ "Welcome to The Madison Planet Stroll". www.idahostatesman.com/. Retrieved 2024-02-19.
  53. ^ "The Thousand-Yard Model, or, The Earth as a Peppercorn". www.universalworkshop.com. Retrieved 2023-05-29.
  54. ^ "The Thousand-Yard Model, or, The Earth as a Peppercorn". noirlab.edu. Retrieved 2023-05-29.
  55. ^ "Naas Solar System". Retrieved 2023-07-27.