🌌 Stone's Star System Generator

Asteroid Belt

Center: 0.26 AU

Composition

Type: Inner (Rocky/Metallic)

A dense region of planetesimals and debris.

Boundary

Planet 1 - Terrestrial

Semi-Major Axis: 0.51 AU

Status: Outer (Cold)

Composition: Rocky (Silicates/Metals)

Physical Data

Mass: 4.63

Radius: 1.85

Gravity: 1.35 G

Time & Orbit

Eccentricity (e): 0.142

Orbit Range: 0.44 AU - 0.58 AU

Year: 235 Days

Day: 42.5 Hours

Environment

Temp: -114 °C

Axial Tilt: 20.3 °

Atmosphere: Thin N₂/CH₄

Biome: Ice Cap/Desert

Planet 2 - Gas Giant

Semi-Major Axis: 0.68 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 705.4

Radius: 10

Gravity: 7.05 G

Time & Orbit

Eccentricity (e): 0.075

Orbit Range: 0.63 AU - 0.73 AU

Year: 362 Days

Day: 12.8 Hours

Environment

Temp: -136 °C

Axial Tilt: 34.7 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (44)

Outer Limit: 92,799,883 km

• M1: 126,261 km (0.113 R)
• M2: 194,776 km (0.068 R)
• M3: 305,479 km (0.074 R)
• M4: 369,656 km (0.068 R)
• M5: 449,242 km (0.107 R)
• M6: 512,822 km (0.06 R)
• M7: 590,463 km (0.058 R)
• M8: 661,821 km (0.082 R)
• M9: 736,470 km (0.113 R)
• M10: 826,079 km (0.059 R)
• M11: 903,122 km (0.081 R)
• M12: 965,953 km (0.069 R)
• M13: 1,113,906 km (0.093 R)
• M14: 1,265,149 km (0.026 R)
• M15: 1,472,492 km (0.032 R)
• M16: 1,547,590 km (0.097 R)
• M17: 1,644,529 km (0.097 R)
• M18: 1,733,091 km (0.113 R)
• M19: 1,817,913 km (0.067 R)
• M20: 1,975,290 km (0.117 R)
• M21: 2,041,861 km (0.071 R)
• M22: 2,199,986 km (0.037 R)
• M23: 2,327,144 km (0.098 R)
• M24: 2,397,605 km (0.068 R)
• M25: 2,522,519 km (0.032 R)
• M26: 2,655,961 km (0.117 R)
• M27: 2,779,229 km (0.09 R)
• M28: 3,012,303 km (0.091 R)
• M29: 3,095,778 km (0.099 R)
• M30: 3,212,614 km (0.076 R)
• M31: 3,278,288 km (0.083 R)
• M32: 3,853,791 km (0.114 R)
• M33: 4,099,879 km (0.091 R)
• M34: 4,185,449 km (0.071 R)
• M35: 4,250,076 km (0.085 R)
• M36: 4,365,715 km (0.041 R)
• M37: 4,519,202 km (0.068 R)
• M38: 4,629,905 km (0.078 R)
• M39: 4,748,984 km (0.072 R)
• M40: 4,838,893 km (0.097 R)
• M41: 5,005,395 km (0.104 R)
• M42: 5,104,728 km (0.066 R)
• M43: 5,212,289 km (0.085 R)
• M44: 5,289,631 km (0.031 R)

Planet 3 - Gas Giant

Semi-Major Axis: 1.06 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 410.4

Radius: 13.6

Gravity: 2.22 G

Time & Orbit

Eccentricity (e): 0.191

Orbit Range: 0.86 AU - 1.26 AU

Year: 705 Days

Day: 7.5 Hours

Environment

Temp: -161 °C

Axial Tilt: 2.7 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (40)

Outer Limit: 92,799,883 km

• M1: 169,794 km (0.07 R)
• M2: 401,221 km (0.086 R)
• M3: 487,988 km (0.083 R)
• M4: 632,201 km (0.107 R)
• M5: 770,579 km (0.115 R)
• M6: 867,817 km (0.102 R)
• M7: 979,567 km (0.104 R)
• M8: 1,128,267 km (0.073 R)
• M9: 1,246,599 km (0.077 R)
• M10: 1,363,734 km (0.112 R)
• M11: 1,449,753 km (0.038 R)
• M12: 1,615,657 km (0.1 R)
• M13: 1,756,877 km (0.074 R)
• M14: 1,895,854 km (0.079 R)
• M15: 1,992,943 km (0.109 R)
• M16: 2,078,513 km (0.094 R)
• M17: 2,239,779 km (0.09 R)
• M18: 2,518,181 km (0.045 R)
• M19: 2,727,169 km (0.115 R)
• M20: 2,852,383 km (0.093 R)
• M21: 3,147,240 km (0.038 R)
• M22: 3,310,152 km (0.074 R)
• M23: 3,428,185 km (0.102 R)
• M24: 3,547,714 km (0.092 R)
• M25: 3,660,660 km (0.084 R)
• M26: 3,857,082 km (0.075 R)
• M27: 4,277,452 km (0.099 R)
• M28: 4,536,855 km (0.045 R)
• M29: 4,650,998 km (0.067 R)
• M30: 4,757,063 km (0.046 R)
• M31: 4,890,953 km (0.099 R)
• M32: 5,254,027 km (0.069 R)
• M33: 5,355,454 km (0.111 R)
• M34: 5,448,205 km (0.062 R)
• M35: 5,891,613 km (0.064 R)
• M36: 6,045,250 km (0.105 R)
• M37: 6,151,614 km (0.064 R)
• M38: 6,287,898 km (0.065 R)
• M39: 6,444,975 km (0.049 R)
• M40: 6,843,355 km (0.107 R)

Planet 4 - Gas Giant

Semi-Major Axis: 1.83 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 632.5

Radius: 9.6

Gravity: 6.86 G

Time & Orbit

Eccentricity (e): 0.175

Orbit Range: 1.51 AU - 2.15 AU

Year: 1598 Days

Day: 11.7 Hours

Environment

Temp: -191 °C

Axial Tilt: 16.6 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (67)

Outer Limit: 92,799,883 km

• M1: 121,623 km (0.051 R)
• M2: 249,529 km (0.112 R)
• M3: 334,950 km (0.103 R)
• M4: 457,171 km (0.117 R)
• M5: 531,072 km (0.041 R)
• M6: 650,900 km (0.12 R)
• M7: 840,890 km (0.045 R)
• M8: 991,535 km (0.077 R)
• M9: 1,057,807 km (0.084 R)
• M10: 1,177,485 km (0.116 R)
• M11: 1,329,177 km (0.084 R)
• M12: 1,459,028 km (0.106 R)
• M13: 1,564,195 km (0.092 R)
• M14: 1,741,768 km (0.097 R)
• M15: 1,853,667 km (0.049 R)
• M16: 1,978,432 km (0.115 R)
• M17: 2,181,885 km (0.114 R)
• M18: 2,280,769 km (0.119 R)
• M19: 2,426,178 km (0.074 R)
• M20: 2,597,917 km (0.12 R)
• M21: 2,773,694 km (0.032 R)
• M22: 2,953,361 km (0.105 R)
• M23: 3,063,016 km (0.098 R)
• M24: 3,324,364 km (0.116 R)
• M25: 3,841,973 km (0.067 R)
• M26: 4,164,805 km (0.112 R)
• M27: 4,329,662 km (0.059 R)
• M28: 4,482,551 km (0.044 R)
• M29: 4,693,932 km (0.101 R)
• M30: 4,937,627 km (0.105 R)
• M31: 5,010,033 km (0.081 R)
• M32: 5,126,719 km (0.039 R)
• M33: 5,303,394 km (0.117 R)
• M34: 5,467,204 km (0.082 R)
• M35: 5,602,440 km (0.105 R)
• M36: 5,693,246 km (0.098 R)
• M37: 5,830,427 km (0.107 R)
• M38: 6,030,440 km (0.083 R)
• M39: 6,263,962 km (0.104 R)
• M40: 6,326,793 km (0.104 R)
• M41: 6,453,054 km (0.079 R)
• M42: 6,548,348 km (0.095 R)
• M43: 6,820,765 km (0.111 R)
• M44: 6,966,474 km (0.092 R)
• M45: 7,080,467 km (0.061 R)
• M46: 7,162,447 km (0.093 R)
• M47: 7,744,233 km (0.057 R)
• M48: 8,169,241 km (0.067 R)
• M49: 8,237,906 km (0.057 R)
• M50: 8,410,542 km (0.066 R)
• M51: 8,479,955 km (0.03 R)
• M52: 8,654,237 km (0.04 R)
• M53: 9,202,064 km (0.055 R)
• M54: 9,399,234 km (0.103 R)
• M55: 9,670,306 km (0.048 R)
• M56: 9,998,972 km (0.081 R)
• M57: 10,461,678 km (0.11 R)
• M58: 10,817,871 km (0.095 R)
• M59: 11,273,696 km (0.089 R)
• M60: 11,619,566 km (0.119 R)
• M61: 11,832,743 km (0.107 R)
• M62: 12,027,669 km (0.112 R)
• M63: 12,480,053 km (0.096 R)
• M64: 12,579,087 km (0.096 R)
• M65: 12,817,845 km (0.105 R)
• M66: 13,038,202 km (0.11 R)
• M67: 13,300,148 km (0.082 R)

Planet 5 - Gas Giant

Semi-Major Axis: 2.16 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 155.6

Radius: 14

Gravity: 0.79 G

Time & Orbit

Eccentricity (e): 0.133

Orbit Range: 1.87 AU - 2.45 AU

Year: 2050 Days

Day: 5.1 Hours

Environment

Temp: -186 °C

Axial Tilt: 11 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (38)

Outer Limit: 92,799,883 km

• M1: 200,312 km (0.079 R)
• M2: 289,173 km (0.071 R)
• M3: 430,543 km (0.116 R)
• M4: 523,892 km (0.09 R)
• M5: 714,479 km (0.095 R)
• M6: 843,882 km (0.064 R)
• M7: 943,663 km (0.03 R)
• M8: 1,142,629 km (0.073 R)
• M9: 1,568,384 km (0.081 R)
• M10: 1,702,573 km (0.078 R)
• M11: 1,791,584 km (0.11 R)
• M12: 2,017,028 km (0.072 R)
• M13: 2,423,186 km (0.116 R)
• M14: 3,060,922 km (0.08 R)
• M15: 3,251,211 km (0.064 R)
• M16: 3,696,563 km (0.072 R)
• M17: 3,942,951 km (0.097 R)
• M18: 4,294,805 km (0.064 R)
• M19: 4,737,465 km (0.065 R)
• M20: 4,865,072 km (0.087 R)
• M21: 5,111,759 km (0.095 R)
• M22: 5,302,646 km (0.088 R)
• M23: 5,495,777 km (0.069 R)
• M24: 5,642,233 km (0.074 R)
• M25: 6,127,379 km (0.114 R)
• M26: 6,266,655 km (0.039 R)
• M27: 6,368,531 km (0.114 R)
• M28: 6,458,290 km (0.105 R)
• M29: 6,548,348 km (0.116 R)
• M30: 6,782,019 km (0.107 R)
• M31: 6,992,055 km (0.111 R)
• M32: 7,084,656 km (0.068 R)
• M33: 7,459,099 km (0.11 R)
• M34: 7,730,620 km (0.117 R)
• M35: 8,920,671 km (0.105 R)
• M36: 9,412,548 km (0.102 R)
• M37: 9,559,005 km (0.078 R)
• M38: 9,987,902 km (0.079 R)

Planet 6 - Gas Giant

Semi-Major Axis: 2.99 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 40.1

Radius: 10.5

Gravity: 0.36 G

Time & Orbit

Eccentricity (e): 0.028

Orbit Range: 2.91 AU - 3.07 AU

Year: 3338 Days

Day: 7.4 Hours

Environment

Temp: -199 °C

Axial Tilt: 38.3 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (29)

Outer Limit: 92,799,883 km

• M1: 132,095 km (0.104 R)
• M2: 220,507 km (0.052 R)
• M3: 364,869 km (0.119 R)
• M4: 628,012 km (0.096 R)
• M5: 787,782 km (0.098 R)
• M6: 1,142,479 km (0.078 R)
• M7: 1,788,443 km (0.066 R)
• M8: 2,005,210 km (0.072 R)
• M9: 2,100,803 km (0.067 R)
• M10: 2,575,926 km (0.05 R)
• M11: 2,759,333 km (0.099 R)
• M12: 3,392,431 km (0.063 R)
• M13: 3,701,201 km (0.112 R)
• M14: 4,211,928 km (0.083 R)
• M15: 4,408,051 km (0.113 R)
• M16: 4,533,414 km (0.12 R)
• M17: 5,178,181 km (0.058 R)
• M18: 5,366,076 km (0.11 R)
• M19: 5,920,485 km (0.102 R)
• M20: 6,386,632 km (0.101 R)
• M21: 6,457,691 km (0.095 R)
• M22: 6,612,375 km (0.09 R)
• M23: 6,708,118 km (0.104 R)
• M24: 7,206,279 km (0.048 R)
• M25: 7,817,386 km (0.119 R)
• M26: 8,575,249 km (0.113 R)
• M27: 8,666,803 km (0.114 R)
• M28: 8,798,000 km (0.086 R)
• M29: 8,890,302 km (0.113 R)

Planet 7 - Ice Giant

Semi-Major Axis: 6.76 AU

Status: Outer (Cold)

Composition: Methane/Ammonia Ices

Physical Data

Mass: 682.4

Radius: 4.9

Gravity: 28.42 G

Time & Orbit

Eccentricity (e): 0.196

Orbit Range: 5.44 AU - 8.08 AU

Year: 11348 Days

Day: 17.4 Hours

Environment

Temp: -224 °C

Axial Tilt: 15.1 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (96)

Outer Limit: 92,799,883 km

• M1: 62,532 km (0.092 R)
• M2: 138,079 km (0.04 R)
• M3: 291,716 km (0.109 R)
• M4: 963,111 km (0.096 R)
• M5: 1,304,942 km (0.055 R)
• M6: 1,805,796 km (0.111 R)
• M7: 1,933,104 km (0.065 R)
• M8: 2,037,074 km (0.112 R)
• M9: 2,499,332 km (0.048 R)
• M10: 2,641,450 km (0.112 R)
• M11: 2,756,939 km (0.104 R)
• M12: 2,933,315 km (0.042 R)
• M13: 3,083,212 km (0.107 R)
• M14: 3,174,317 km (0.113 R)
• M15: 3,297,287 km (0.068 R)
• M16: 3,421,752 km (0.108 R)
• M17: 3,484,583 km (0.105 R)
• M18: 3,611,293 km (0.072 R)
• M19: 3,934,873 km (0.063 R)
• M20: 4,369,455 km (0.119 R)
• M21: 4,471,929 km (0.111 R)
• M22: 4,854,301 km (0.067 R)
• M23: 5,283,498 km (0.12 R)
• M24: 5,502,509 km (0.118 R)
• M25: 5,799,311 km (0.12 R)
• M26: 5,911,958 km (0.088 R)
• M27: 5,949,657 km (0.12 R)
• M28: 7,400,158 km (0.118 R)
• M29: 7,934,521 km (0.1 R)
• M30: 7,976,259 km (0.069 R)
• M31: 8,438,816 km (0.068 R)
• M32: 8,566,572 km (0.114 R)
• M33: 8,780,797 km (0.052 R)
• M34: 9,040,199 km (0.115 R)
• M35: 9,127,265 km (0.06 R)
• M36: 9,699,776 km (0.084 R)
• M37: 10,511,494 km (0.088 R)
• M38: 11,018,182 km (0.089 R)
• M39: 11,064,707 km (0.101 R)
• M40: 12,440,260 km (0.068 R)
• M41: 12,634,139 km (0.077 R)
• M42: 13,469,493 km (0.094 R)
• M43: 14,525,804 km (0.031 R)
• M44: 14,627,680 km (0.112 R)
• M45: 14,730,005 km (0.106 R)
• M46: 14,986,565 km (0.118 R)
• M47: 16,503,637 km (0.09 R)
• M48: 18,123,932 km (0.12 R)
• M49: 18,509,146 km (0.111 R)
• M50: 21,454,579 km (0.056 R)
• M51: 22,625,631 km (0.096 R)
• M52: 22,981,075 km (0.064 R)
• M53: 23,457,694 km (0.065 R)
• M54: 23,637,212 km (0.113 R)
• M55: 24,058,030 km (0.037 R)
• M56: 25,642,721 km (0.084 R)
• M57: 25,951,191 km (0.052 R)
• M58: 26,013,125 km (0.052 R)
• M59: 26,696,937 km (0.094 R)
• M60: 26,759,319 km (0.03 R)
• M61: 27,072,278 km (0.094 R)
• M62: 27,386,583 km (0.103 R)
• M63: 27,575,675 km (0.108 R)
• M64: 28,911,434 km (0.077 R)
• M65: 29,039,789 km (0.074 R)
• M66: 29,813,659 km (0.101 R)
• M67: 30,203,212 km (0.086 R)
• M68: 30,659,635 km (0.113 R)
• M69: 32,441,944 km (0.118 R)
• M70: 33,783,538 km (0.095 R)
• M71: 35,006,351 km (0.113 R)
• M72: 35,143,233 km (0.114 R)
• M73: 35,760,922 km (0.042 R)
• M74: 37,006,923 km (0.104 R)
• M75: 37,285,773 km (0.12 R)
• M76: 37,985,891 km (0.118 R)
• M77: 38,267,135 km (0.108 R)
• M78: 39,683,977 km (0.077 R)
• M79: 40,973,510 km (0.082 R)
• M80: 41,623,513 km (0.116 R)
• M81: 41,913,583 km (0.104 R)
• M82: 43,226,604 km (0.046 R)
• M83: 43,593,867 km (0.092 R)
• M84: 44,109,531 km (0.09 R)
• M85: 44,331,235 km (0.117 R)
• M86: 44,627,438 km (0.118 R)
• M87: 45,743,738 km (0.08 R)
• M88: 46,342,728 km (0.045 R)
• M89: 47,548,786 km (0.073 R)
• M90: 47,700,328 km (0.06 R)
• M91: 49,070,794 km (0.097 R)
• M92: 50,531,318 km (0.092 R)
• M93: 50,686,003 km (0.041 R)
• M94: 50,995,670 km (0.06 R)
• M95: 51,461,219 km (0.108 R)
• M96: 51,539,010 km (0.083 R)

Planet 8 - Ice Giant

Semi-Major Axis: 10.78 AU

Status: Outer (Cold)

Composition: Methane/Ammonia Ices

Physical Data

Mass: 951.8

Radius: 5.9

Gravity: 27.34 G

Time & Orbit

Eccentricity (e): 0.006

Orbit Range: 10.72 AU - 10.84 AU

Year: 22853 Days

Day: 23.7 Hours

Environment

Temp: -229 °C

Axial Tilt: 39.5 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (97)

Outer Limit: 92,799,883 km

• M1: 297,251 km (0.068 R)
• M2: 335,698 km (0.078 R)
• M3: 375,939 km (0.105 R)
• M4: 1,335,311 km (0.089 R)
• M5: 2,452,807 km (0.1 R)
• M6: 2,660,897 km (0.118 R)
• M7: 3,410,233 km (0.04 R)
• M8: 3,689,532 km (0.073 R)
• M9: 4,024,781 km (0.098 R)
• M10: 4,122,319 km (0.071 R)
• M11: 7,632,035 km (0.052 R)
• M12: 8,743,098 km (0.051 R)
• M13: 9,576,508 km (0.084 R)
• M14: 10,368,329 km (0.115 R)
• M15: 10,975,697 km (0.078 R)
• M16: 11,943,445 km (0.104 R)
• M17: 12,083,918 km (0.108 R)
• M18: 12,437,567 km (0.119 R)
• M19: 13,445,557 km (0.089 R)
• M20: 14,930,615 km (0.094 R)
• M21: 15,157,855 km (0.099 R)
• M22: 15,692,368 km (0.108 R)
• M23: 16,000,689 km (0.073 R)
• M24: 16,155,523 km (0.108 R)
• M25: 16,466,836 km (0.094 R)
• M26: 17,095,297 km (0.037 R)
• M27: 17,891,905 km (0.099 R)
• M28: 18,133,207 km (0.104 R)
• M29: 18,213,840 km (0.115 R)
• M30: 18,619,101 km (0.084 R)
• M31: 18,700,482 km (0.053 R)
• M32: 18,863,693 km (0.078 R)
• M33: 19,027,204 km (0.036 R)
• M34: 20,353,239 km (0.089 R)
• M35: 21,367,064 km (0.091 R)
• M36: 21,708,596 km (0.107 R)
• M37: 22,483,812 km (0.118 R)
• M38: 22,744,262 km (0.094 R)
• M39: 23,884,347 km (0.096 R)
• M40: 24,238,745 km (0.094 R)
• M41: 25,132,592 km (0.099 R)
• M42: 26,128,315 km (0.1 R)
• M43: 26,310,675 km (0.109 R)
• M44: 26,952,450 km (0.112 R)
• M45: 27,692,211 km (0.109 R)
• M46: 29,951,289 km (0.105 R)
• M47: 31,102,893 km (0.06 R)
• M48: 31,392,964 km (0.081 R)
• M49: 32,857,078 km (0.106 R)
• M50: 36,155,711 km (0.115 R)
• M51: 36,359,014 km (0.06 R)
• M52: 37,689,538 km (0.106 R)
• M53: 38,412,544 km (0.094 R)
• M54: 38,620,037 km (0.112 R)
• M55: 40,187,523 km (0.098 R)
• M56: 41,032,003 km (0.101 R)
• M57: 42,309,719 km (0.117 R)
• M58: 43,276,570 km (0.078 R)
• M59: 44,141,993 km (0.114 R)
• M60: 45,890,044 km (0.097 R)
• M61: 46,883,225 km (0.09 R)
• M62: 48,554,233 km (0.093 R)
• M63: 51,610,966 km (0.057 R)
• M64: 52,298,668 km (0.092 R)
• M65: 53,104,701 km (0.055 R)
• M66: 54,379,724 km (0.025 R)
• M67: 55,196,378 km (0.08 R)
• M68: 55,430,499 km (0.108 R)
• M69: 56,134,656 km (0.08 R)
• M70: 56,959,988 km (0.075 R)
• M71: 61,630,882 km (0.057 R)
• M72: 62,238,549 km (0.108 R)
• M73: 62,604,166 km (0.102 R)
• M74: 64,196,336 km (0.118 R)
• M75: 66,921,261 km (0.113 R)
• M76: 68,926,621 km (0.08 R)
• M77: 70,570,552 km (0.112 R)
• M78: 70,951,727 km (0.083 R)
• M79: 75,578,939 km (0.096 R)
• M80: 77,273,583 km (0.073 R)
• M81: 77,666,577 km (0.113 R)
• M82: 77,928,822 km (0.025 R)
• M83: 79,244,685 km (0.116 R)
• M84: 80,567,878 km (0.092 R)
• M85: 82,833,987 km (0.055 R)
• M86: 83,235,956 km (0.073 R)
• M87: 83,370,145 km (0.1 R)
• M88: 83,907,651 km (0.087 R)
• M89: 84,985,802 km (0.097 R)
• M90: 85,526,748 km (0.093 R)
• M91: 86,068,741 km (0.038 R)
• M92: 86,204,277 km (0.066 R)
• M93: 86,747,766 km (0.118 R)
• M94: 87,019,885 km (0.108 R)
• M95: 88,247,934 km (0.114 R)
• M96: 89,756,778 km (0.103 R)
• M97: 90,997,542 km (0.11 R)

Kuiper Belt

Range: 30 - 50 AU

Composition

Type: Dwarf Planets/TNOs (Ices)

Reservoir of dwarf planets and volatile ices.

Outer System

Oort Cloud

Range: 268 - 19,515 AU

Composition

Type: Cometary Reservoir

System's final boundary, containing trillions of icy planetesimals.

Gravitational Limit