G9V Star System Generated (Seed: 1766272541)
Star Details
Spectral Class: G0V
Temperature: 5,920 K
Mass: 1.08 sol
Luminosity: 1.31 lux
Habitable Zone (HZ)
Inner Boundary: 1.09 AU
Outer Boundary: 1.57 AU
Physical Limits
Snow Line: 5.49 AU
Max System Radius: 20.8 AU
Planetary System (9 Planets)
Planet 1 - Terrestrial
Semi-Major Axis: 0.57 AU
Status: Inner (Hot)
Composition: Rocky (Silicates/Metals)
Physical Data
Mass: 1
Radius: 1
Gravity: 1 G
Time & Orbit
Eccentricity (e): 0.106
Orbit Range: 0.51 AU - 0.63 AU
Year: 151 Days
Day: 45.1 Hours
Environment
Temp: 184 °C
Axial Tilt: 34.8 °
Atmosphere: Dense COâ‚‚
Biome: Volcanic/Barren
Satellites (1)
Outer Limit: 45,176,432 km
- M1: 302,038 km (0.104 R)
Planet 2 - Terrestrial
Semi-Major Axis: 0.62 AU
Status: Inner (Hot)
Composition: Rocky (Silicates/Metals)
Physical Data
Mass: 2.65
Radius: 1.48
Gravity: 1.21 G
Time & Orbit
Eccentricity (e): 0.068
Orbit Range: 0.58 AU - 0.66 AU
Year: 172 Days
Day: 32.5 Hours
Environment
Temp: 180 °C
Axial Tilt: 41.5 °
Atmosphere: Dense COâ‚‚
Biome: Volcanic/Barren
Satellites (2)
Outer Limit: 45,176,432 km
- M1: 121,324 km (0.106 R)
- M2: 225,594 km (0.115 R)
Planet 3 - Terrestrial
Semi-Major Axis: 1.01 AU
Status: Inner (Hot)
Composition: Rocky (Silicates/Metals)
Physical Data
Mass: 0.33
Radius: 0.64
Gravity: 0.81 G
Time & Orbit
Eccentricity (e): 0.12
Orbit Range: 0.89 AU - 1.13 AU
Year: 357 Days
Day: 28.2 Hours
Environment
Temp: 132 °C
Axial Tilt: 47.7 °
Atmosphere: Dense COâ‚‚
Biome: Volcanic/Barren
Planet 4 - Terrestrial
Semi-Major Axis: 4.48 AU
Status: Outer (Cold)
Composition: Rocky (Silicates/Metals)
Physical Data
Mass: 1.35
Radius: 1.13
Gravity: 1.06 G
Time & Orbit
Eccentricity (e): 0.071
Orbit Range: 4.16 AU - 4.8 AU
Year: 3333 Days
Day: 26.4 Hours
Environment
Temp: -132 °C
Axial Tilt: 78.8 °
Atmosphere: Thin Nâ‚‚/CHâ‚„
Biome: Ice Cap/Desert
Planet 5 - Gas Giant
Semi-Major Axis: 5.88 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 378
Radius: 13.4
Gravity: 2.11 G
Time & Orbit
Eccentricity (e): 0.095
Orbit Range: 5.32 AU - 6.44 AU
Year: 5011 Days
Day: 15 Hours
Environment
Temp: -135 °C
Axial Tilt: 45.2 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (73)
Outer Limit: 45,176,432 km
- M1: 203,154 km (0.107 R)
- M2: 294,708 km (0.112 R)
- M3: 394,041 km (0.086 R)
- M4: 501,901 km (0.102 R)
- M5: 593,904 km (0.098 R)
- M6: 809,773 km (0.109 R)
- M7: 1,065,436 km (0.032 R)
- M8: 1,375,253 km (0.108 R)
- M9: 1,626,727 km (0.036 R)
- M10: 1,802,954 km (0.097 R)
- M11: 2,271,943 km (0.106 R)
- M12: 2,453,405 km (0.115 R)
- M13: 3,099,668 km (0.112 R)
- M14: 3,227,873 km (0.109 R)
- M15: 3,414,123 km (0.116 R)
- M16: 3,565,815 km (0.095 R)
- M17: 4,296,301 km (0.047 R)
- M18: 4,647,557 km (0.084 R)
- M19: 4,837,247 km (0.077 R)
- M20: 5,181,023 km (0.076 R)
- M21: 5,466,306 km (0.12 R)
- M22: 6,144,284 km (0.088 R)
- M23: 6,236,735 km (0.071 R)
- M24: 6,399,647 km (0.078 R)
- M25: 6,801,168 km (0.106 R)
- M26: 6,896,761 km (0.042 R)
- M27: 7,529,859 km (0.115 R)
- M28: 7,703,393 km (0.069 R)
- M29: 7,828,307 km (0.055 R)
- M30: 8,054,798 km (0.106 R)
- M31: 8,156,076 km (0.06 R)
- M32: 8,669,197 km (0.114 R)
- M33: 8,903,616 km (0.116 R)
- M34: 9,325,482 km (0.115 R)
- M35: 9,834,863 km (0.101 R)
- M36: 10,025,002 km (0.065 R)
- M37: 10,161,435 km (0.062 R)
- M38: 10,491,448 km (0.103 R)
- M39: 10,993,349 km (0.095 R)
- M40: 11,303,765 km (0.108 R)
- M41: 11,389,035 km (0.111 R)
- M42: 11,789,509 km (0.104 R)
- M43: 12,311,157 km (0.105 R)
- M44: 13,407,111 km (0.044 R)
- M45: 13,618,044 km (0.056 R)
- M46: 13,799,656 km (0.06 R)
- M47: 13,982,165 km (0.104 R)
- M48: 15,187,475 km (0.111 R)
- M49: 15,313,137 km (0.087 R)
- M50: 15,628,340 km (0.106 R)
- M51: 15,882,208 km (0.042 R)
- M52: 16,041,529 km (0.034 R)
- M53: 16,201,449 km (0.084 R)
- M54: 16,393,982 km (0.076 R)
- M55: 16,684,202 km (0.066 R)
- M56: 17,565,184 km (0.082 R)
- M57: 17,796,013 km (0.087 R)
- M58: 18,027,890 km (0.118 R)
- M59: 18,662,484 km (0.114 R)
- M60: 18,898,101 km (0.107 R)
- M61: 18,999,378 km (0.118 R)
- M62: 19,304,259 km (0.08 R)
- M63: 19,645,043 km (0.062 R)
- M64: 19,884,699 km (0.092 R)
- M65: 20,090,844 km (0.105 R)
- M66: 20,540,236 km (0.06 R)
- M67: 20,644,357 km (0.068 R)
- M68: 20,853,195 km (0.069 R)
- M69: 21,837,100 km (0.057 R)
- M70: 22,192,096 km (0.105 R)
- M71: 23,088,038 km (0.099 R)
- M72: 23,304,955 km (0.055 R)
- M73: 24,215,557 km (0.034 R)
Planet 6 - Gas Giant
Semi-Major Axis: 6.26 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 56
Radius: 12.7
Gravity: 0.35 G
Time & Orbit
Eccentricity (e): 0.023
Orbit Range: 6.12 AU - 6.4 AU
Year: 5505 Days
Day: 12.6 Hours
Environment
Temp: -143 °C
Axial Tilt: 23.6 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (58)
Outer Limit: 45,176,432 km
- M1: 159,172 km (0.096 R)
- M2: 331,359 km (0.108 R)
- M3: 562,488 km (0.112 R)
- M4: 675,734 km (0.049 R)
- M5: 881,580 km (0.099 R)
- M6: 1,320,201 km (0.116 R)
- M7: 1,701,676 km (0.099 R)
- M8: 1,802,654 km (0.118 R)
- M9: 2,021,217 km (0.051 R)
- M10: 2,161,091 km (0.114 R)
- M11: 2,293,186 km (0.073 R)
- M12: 2,462,082 km (0.026 R)
- M13: 2,588,791 km (0.119 R)
- M14: 2,729,413 km (0.071 R)
- M15: 2,836,675 km (0.1 R)
- M16: 3,067,654 km (0.106 R)
- M17: 3,191,820 km (0.05 R)
- M18: 3,509,716 km (0.059 R)
- M19: 3,692,375 km (0.049 R)
- M20: 4,039,741 km (0.1 R)
- M21: 4,969,192 km (0.062 R)
- M22: 5,086,328 km (0.109 R)
- M23: 5,579,253 km (0.094 R)
- M24: 5,716,284 km (0.11 R)
- M25: 5,870,071 km (0.119 R)
- M26: 6,371,074 km (0.056 R)
- M27: 6,466,667 km (0.036 R)
- M28: 6,626,886 km (0.1 R)
- M29: 6,772,296 km (0.097 R)
- M30: 6,853,378 km (0.038 R)
- M31: 6,967,670 km (0.106 R)
- M32: 7,148,534 km (0.099 R)
- M33: 7,887,548 km (0.07 R)
- M34: 8,024,579 km (0.085 R)
- M35: 8,335,743 km (0.063 R)
- M36: 8,440,461 km (0.113 R)
- M37: 8,527,976 km (0.103 R)
- M38: 8,810,118 km (0.097 R)
- M39: 8,898,829 km (0.116 R)
- M40: 9,077,300 km (0.108 R)
- M41: 9,202,962 km (0.084 R)
- M42: 9,401,628 km (0.055 R)
- M43: 9,510,685 km (0.12 R)
- M44: 10,453,750 km (0.118 R)
- M45: 10,984,373 km (0.078 R)
- M46: 11,156,710 km (0.104 R)
- M47: 11,291,498 km (0.101 R)
- M48: 11,407,436 km (0.105 R)
- M49: 11,620,912 km (0.11 R)
- M50: 11,718,450 km (0.084 R)
- M51: 11,914,274 km (0.106 R)
- M52: 12,229,776 km (0.115 R)
- M53: 12,628,155 km (0.087 R)
- M54: 12,869,306 km (0.098 R)
- M55: 13,010,676 km (0.083 R)
- M56: 13,132,299 km (0.098 R)
- M57: 13,417,433 km (0.095 R)
- M58: 13,766,445 km (0.115 R)
Planet 7 - Gas Giant
Semi-Major Axis: 8.13 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 417.7
Radius: 10.7
Gravity: 3.65 G
Time & Orbit
Eccentricity (e): 0.2
Orbit Range: 6.5 AU - 9.76 AU
Year: 8147 Days
Day: 12 Hours
Environment
Temp: -151 °C
Axial Tilt: 12.3 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (79)
Outer Limit: 45,176,432 km
- M1: 211,382 km (0.117 R)
- M2: 325,824 km (0.081 R)
- M3: 576,401 km (0.107 R)
- M4: 745,745 km (0.069 R)
- M5: 1,070,971 km (0.065 R)
- M6: 1,216,829 km (0.075 R)
- M7: 1,675,496 km (0.101 R)
- M8: 1,846,487 km (0.047 R)
- M9: 2,652,819 km (0.114 R)
- M10: 2,763,521 km (0.076 R)
- M11: 2,898,309 km (0.058 R)
- M12: 3,128,091 km (0.066 R)
- M13: 3,340,072 km (0.111 R)
- M14: 3,411,729 km (0.081 R)
- M15: 3,581,074 km (0.069 R)
- M16: 3,728,577 km (0.092 R)
- M17: 3,827,910 km (0.106 R)
- M18: 3,903,008 km (0.071 R)
- M19: 4,182,906 km (0.118 R)
- M20: 4,469,236 km (0.059 R)
- M21: 4,654,887 km (0.096 R)
- M22: 4,789,077 km (0.095 R)
- M23: 4,897,385 km (0.065 R)
- M24: 5,199,424 km (0.076 R)
- M25: 5,338,699 km (0.09 R)
- M26: 5,908,368 km (0.105 R)
- M27: 6,497,484 km (0.083 R)
- M28: 6,587,393 km (0.097 R)
- M29: 6,708,118 km (0.043 R)
- M30: 7,012,849 km (0.1 R)
- M31: 7,384,749 km (0.11 R)
- M32: 7,731,218 km (0.12 R)
- M33: 8,180,012 km (0.104 R)
- M34: 9,237,519 km (0.11 R)
- M35: 9,782,205 km (0.062 R)
- M36: 10,938,746 km (0.097 R)
- M37: 11,081,911 km (0.052 R)
- M38: 11,514,997 km (0.114 R)
- M39: 11,587,701 km (0.117 R)
- M40: 12,435,024 km (0.102 R)
- M41: 13,416,984 km (0.11 R)
- M42: 15,454,507 km (0.053 R)
- M43: 15,574,934 km (0.048 R)
- M44: 17,461,213 km (0.119 R)
- M45: 18,176,440 km (0.098 R)
- M46: 18,388,720 km (0.097 R)
- M47: 18,516,476 km (0.091 R)
- M48: 18,644,383 km (0.113 R)
- M49: 20,291,156 km (0.044 R)
- M50: 21,803,740 km (0.098 R)
- M51: 22,255,526 km (0.11 R)
- M52: 23,444,679 km (0.112 R)
- M53: 23,629,432 km (0.103 R)
- M54: 24,140,010 km (0.061 R)
- M55: 24,233,209 km (0.111 R)
- M56: 24,842,222 km (0.1 R)
- M57: 24,983,443 km (0.03 R)
- M58: 25,551,017 km (0.101 R)
- M59: 25,693,584 km (0.051 R)
- M60: 26,266,544 km (0.061 R)
- M61: 26,458,478 km (0.097 R)
- M62: 26,843,692 km (0.111 R)
- M63: 27,182,382 km (0.078 R)
- M64: 27,473,799 km (0.086 R)
- M65: 27,766,113 km (0.114 R)
- M66: 27,912,719 km (0.107 R)
- M67: 29,243,691 km (0.119 R)
- M68: 29,592,104 km (0.118 R)
- M69: 30,696,137 km (0.068 R)
- M70: 30,797,115 km (0.051 R)
- M71: 30,898,243 km (0.096 R)
- M72: 31,100,949 km (0.035 R)
- M73: 31,354,816 km (0.076 R)
- M74: 32,171,920 km (0.111 R)
- M75: 32,377,318 km (0.087 R)
- M76: 34,036,059 km (0.032 R)
- M77: 34,875,602 km (0.106 R)
- M78: 35,245,109 km (0.081 R)
- M79: 35,351,024 km (0.096 R)
Planet 8 - Gas Giant
Semi-Major Axis: 10.02 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 792.8
Radius: 9.3
Gravity: 9.17 G
Time & Orbit
Eccentricity (e): 0.186
Orbit Range: 8.16 AU - 11.88 AU
Year: 11148 Days
Day: 13.7 Hours
Environment
Temp: -178 °C
Axial Tilt: 38.4 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (92)
Outer Limit: 45,176,432 km
- M1: 257,009 km (0.052 R)
- M2: 316,399 km (0.118 R)
- M3: 531,521 km (0.063 R)
- M4: 929,003 km (0.064 R)
- M5: 1,137,093 km (0.105 R)
- M6: 1,291,778 km (0.082 R)
- M7: 1,549,236 km (0.113 R)
- M8: 1,646,923 km (0.12 R)
- M9: 2,005,359 km (0.112 R)
- M10: 2,444,728 km (0.064 R)
- M11: 2,617,215 km (0.076 R)
- M12: 3,571,051 km (0.039 R)
- M13: 3,966,887 km (0.077 R)
- M14: 4,034,355 km (0.096 R)
- M15: 4,481,653 km (0.066 R)
- M16: 4,693,334 km (0.118 R)
- M17: 4,944,658 km (0.076 R)
- M18: 5,053,715 km (0.104 R)
- M19: 6,463,526 km (0.12 R)
- M20: 6,904,989 km (0.093 R)
- M21: 7,191,020 km (0.117 R)
- M22: 7,564,416 km (0.044 R)
- M23: 8,286,974 km (0.094 R)
- M24: 8,810,267 km (0.109 R)
- M25: 9,524,747 km (0.098 R)
- M26: 9,751,836 km (0.111 R)
- M27: 11,728,922 km (0.118 R)
- M28: 12,119,372 km (0.106 R)
- M29: 14,186,067 km (0.088 R)
- M30: 14,289,589 km (0.11 R)
- M31: 14,863,895 km (0.079 R)
- M32: 16,305,121 km (0.065 R)
- M33: 16,468,033 km (0.115 R)
- M34: 16,795,353 km (0.092 R)
- M35: 17,679,028 km (0.08 R)
- M36: 18,070,376 km (0.108 R)
- M37: 20,302,376 km (0.055 R)
- M38: 20,947,591 km (0.085 R)
- M39: 21,065,624 km (0.103 R)
- M40: 21,957,826 km (0.091 R)
- M41: 22,077,803 km (0.063 R)
- M42: 22,378,495 km (0.093 R)
- M43: 22,438,783 km (0.069 R)
- M44: 22,801,707 km (0.115 R)
- M45: 22,923,181 km (0.068 R)
- M46: 23,779,180 km (0.096 R)
- M47: 24,025,568 km (0.109 R)
- M48: 24,770,266 km (0.039 R)
- M49: 25,901,226 km (0.08 R)
- M50: 25,964,506 km (0.079 R)
- M51: 26,600,745 km (0.04 R)
- M52: 27,823,409 km (0.034 R)
- M53: 28,213,410 km (0.111 R)
- M54: 28,539,683 km (0.077 R)
- M55: 29,196,119 km (0.057 R)
- M56: 29,857,641 km (0.055 R)
- M57: 30,323,488 km (0.119 R)
- M58: 31,397,452 km (0.105 R)
- M59: 32,007,063 km (0.109 R)
- M60: 33,169,139 km (0.111 R)
- M61: 33,444,698 km (0.091 R)
- M62: 33,720,856 km (0.039 R)
- M63: 37,022,631 km (0.099 R)
- M64: 38,025,834 km (0.111 R)
- M65: 38,530,876 km (0.1 R)
- M66: 38,675,538 km (0.109 R)
- M67: 39,256,127 km (0.116 R)
- M68: 39,401,686 km (0.104 R)
- M69: 39,547,394 km (0.061 R)
- M70: 40,059,019 km (0.059 R)
- M71: 40,646,489 km (0.057 R)
- M72: 41,088,850 km (0.074 R)
- M73: 41,310,704 km (0.087 R)
- M74: 42,799,502 km (0.095 R)
- M75: 43,324,890 km (0.05 R)
- M76: 43,475,236 km (0.111 R)
- M77: 43,550,633 km (0.112 R)
- M78: 44,078,863 km (0.112 R)
- M79: 44,381,799 km (0.095 R)
- M80: 44,609,337 km (0.067 R)
- M81: 44,685,333 km (0.076 R)
- M82: 45,753,162 km (0.065 R)
- M83: 47,836,163 km (0.077 R)
- M84: 48,225,267 km (0.099 R)
- M85: 48,303,208 km (0.069 R)
- M86: 48,693,509 km (0.081 R)
- M87: 50,978,466 km (0.094 R)
- M88: 51,296,362 km (0.102 R)
- M89: 51,854,212 km (0.069 R)
- M90: 52,333,973 km (0.107 R)
- M91: 52,494,342 km (0.091 R)
- M92: 52,976,047 km (0.108 R)
Planet 9 - Gas Giant
Semi-Major Axis: 11.89 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 276.2
Radius: 11.5
Gravity: 2.09 G
Time & Orbit
Eccentricity (e): 0.196
Orbit Range: 9.56 AU - 14.22 AU
Year: 14410 Days
Day: 8.4 Hours
Environment
Temp: -179 °C
Axial Tilt: 10.2 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (85)
Outer Limit: 45,176,432 km
- M1: 169,345 km (0.047 R)
- M2: 300,093 km (0.102 R)
- M3: 437,873 km (0.117 R)
- M4: 646,562 km (0.101 R)
- M5: 788,381 km (0.033 R)
- M6: 1,105,229 km (0.06 R)
- M7: 1,318,556 km (0.108 R)
- M8: 1,545,795 km (0.108 R)
- M9: 1,631,664 km (0.12 R)
- M10: 1,922,183 km (0.096 R)
- M11: 2,109,330 km (0.096 R)
- M12: 2,603,901 km (0.119 R)
- M13: 2,971,313 km (0.096 R)
- M14: 3,133,926 km (0.036 R)
- M15: 5,273,175 km (0.12 R)
- M16: 5,637,596 km (0.091 R)
- M17: 5,873,811 km (0.085 R)
- M18: 6,010,244 km (0.068 R)
- M19: 6,637,358 km (0.114 R)
- M20: 6,886,888 km (0.094 R)
- M21: 6,958,695 km (0.086 R)
- M22: 7,067,003 km (0.104 R)
- M23: 7,579,825 km (0.077 R)
- M24: 8,256,755 km (0.086 R)
- M25: 8,333,200 km (0.093 R)
- M26: 8,409,794 km (0.074 R)
- M27: 8,641,222 km (0.077 R)
- M28: 9,748,844 km (0.11 R)
- M29: 9,992,091 km (0.119 R)
- M30: 10,237,281 km (0.066 R)
- M31: 10,484,417 km (0.081 R)
- M32: 10,567,294 km (0.113 R)
- M33: 10,817,123 km (0.09 R)
- M34: 11,706,931 km (0.117 R)
- M35: 12,226,036 km (0.085 R)
- M36: 13,152,346 km (0.037 R)
- M37: 15,306,705 km (0.108 R)
- M38: 15,447,775 km (0.037 R)
- M39: 15,921,701 km (0.062 R)
- M40: 16,400,265 km (0.098 R)
- M41: 17,617,393 km (0.11 R)
- M42: 17,913,896 km (0.109 R)
- M43: 18,913,958 km (0.119 R)
- M44: 19,369,932 km (0.117 R)
- M45: 19,778,334 km (0.057 R)
- M46: 20,034,895 km (0.052 R)
- M47: 21,439,918 km (0.113 R)
- M48: 22,074,662 km (0.028 R)
- M49: 22,287,540 km (0.075 R)
- M50: 22,394,352 km (0.049 R)
- M51: 22,661,833 km (0.068 R)
- M52: 23,470,859 km (0.105 R)
- M53: 23,579,467 km (0.089 R)
- M54: 24,070,148 km (0.076 R)
- M55: 24,619,322 km (0.115 R)
- M56: 25,061,682 km (0.084 R)
- M57: 25,730,086 km (0.058 R)
- M58: 26,010,432 km (0.1 R)
- M59: 26,630,515 km (0.11 R)
- M60: 27,426,825 km (0.106 R)
- M61: 28,115,573 km (0.079 R)
- M62: 28,288,658 km (0.042 R)
- M63: 28,751,963 km (0.081 R)
- M64: 30,215,928 km (0.112 R)
- M65: 30,570,774 km (0.097 R)
- M66: 31,584,000 km (0.095 R)
- M67: 32,124,946 km (0.111 R)
- M68: 32,608,297 km (0.107 R)
- M69: 33,337,885 km (0.115 R)
- M70: 33,643,364 km (0.087 R)
- M71: 34,257,314 km (0.104 R)
- M72: 34,565,635 km (0.079 R)
- M73: 35,371,669 km (0.08 R)
- M74: 35,620,899 km (0.057 R)
- M75: 36,246,666 km (0.066 R)
- M76: 38,401,175 km (0.047 R)
- M77: 38,978,324 km (0.081 R)
- M78: 39,235,782 km (0.074 R)
- M79: 39,493,838 km (0.04 R)
- M80: 40,076,522 km (0.057 R)
- M81: 42,105,069 km (0.114 R)
- M82: 42,303,286 km (0.08 R)
- M83: 42,435,530 km (0.099 R)
- M84: 43,165,269 km (0.092 R)
- M85: 45,108,844 km (0.068 R)
Kuiper Belt
Range: 31.2 - 48.2 AU
Composition
Type: Dwarf Planets/TNOs (Ices)
Reservoir of dwarf planets and volatile ices.
Outer System
Oort Cloud
Range: 331 - 15,464 AU
Composition
Type: Cometary Reservoir
System's final boundary, containing trillions of icy planetesimals.