Star System Generated (Seed: 1768495228)
Star Details
Spectral Class: M1V
Temperature: 3,483 K
Mass: 0.32 sol
Luminosity: 0.02 lux
Habitable Zone (HZ)
Inner Boundary: 0.13 AU
Outer Boundary: 0.19 AU
Physical Limits
Snow Line: 0.68 AU
Max System Radius: 11.3 AU
Planetary System (9 Planets)
Planet 1 - Terrestrial
Semi-Major Axis: 0.51 AU
Status: Outer (Cold)
Composition: Rocky (Silicates/Metals)
Physical Data
Mass: 4.44
Radius: 1.82
Gravity: 1.34 G
Time & Orbit
Eccentricity (e): 0.198
Orbit Range: 0.41 AU - 0.61 AU
Year: 235 Days
Day: 43.4 Hours
Environment
Temp: -116 °C
Axial Tilt: 9.3 °
Atmosphere: Thin Nâ‚‚/CHâ‚„
Biome: Ice Cap/Desert
Satellites (2)
Outer Limit: 33,849,878 km
- M1: 574,456 km (0.078 R)
- M2: 618,886 km (0.103 R)
Planet 2 - Terrestrial
Semi-Major Axis: 0.53 AU
Status: Outer (Cold)
Composition: Rocky (Silicates/Metals)
Physical Data
Mass: 1.9
Radius: 1.29
Gravity: 1.14 G
Time & Orbit
Eccentricity (e): 0.196
Orbit Range: 0.43 AU - 0.63 AU
Year: 249 Days
Day: 28.5 Hours
Environment
Temp: -111 °C
Axial Tilt: 8.1 °
Atmosphere: Thin Nâ‚‚/CHâ‚„
Biome: Ice Cap/Desert
Planet 3 - Gas Giant
Semi-Major Axis: 1.14 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 10.3
Radius: 9.3
Gravity: 0.12 G
Time & Orbit
Eccentricity (e): 0.042
Orbit Range: 1.09 AU - 1.19 AU
Year: 786 Days
Day: 6.1 Hours
Environment
Temp: -156 °C
Axial Tilt: 37.1 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (24)
Outer Limit: 33,849,878 km
- M1: 141,370 km (0.113 R)
- M2: 210,933 km (0.07 R)
- M3: 288,574 km (0.116 R)
- M4: 346,768 km (0.061 R)
- M5: 416,929 km (0.093 R)
- M6: 499,956 km (0.115 R)
- M7: 572,511 km (0.116 R)
- M8: 639,381 km (0.073 R)
- M9: 723,605 km (0.071 R)
- M10: 788,381 km (0.105 R)
- M11: 883,974 km (0.102 R)
- M12: 974,481 km (0.068 R)
- M13: 1,063,641 km (0.073 R)
- M14: 1,131,110 km (0.089 R)
- M15: 1,217,577 km (0.119 R)
- M16: 1,275,621 km (0.109 R)
- M17: 1,408,015 km (0.067 R)
- M18: 1,523,206 km (0.09 R)
- M19: 1,597,107 km (0.089 R)
- M20: 1,757,476 km (0.107 R)
- M21: 1,841,101 km (0.077 R)
- M22: 1,911,412 km (0.12 R)
- M23: 2,030,492 km (0.036 R)
- M24: 2,170,665 km (0.107 R)
Planet 4 - Gas Giant
Semi-Major Axis: 1.43 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 503.5
Radius: 8.3
Gravity: 7.31 G
Time & Orbit
Eccentricity (e): 0.153
Orbit Range: 1.21 AU - 1.65 AU
Year: 1104 Days
Day: 5.7 Hours
Environment
Temp: -173 °C
Axial Tilt: 8.6 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (45)
Outer Limit: 33,849,878 km
- M1: 104,868 km (0.116 R)
- M2: 182,061 km (0.08 R)
- M3: 244,443 km (0.107 R)
- M4: 338,839 km (0.064 R)
- M5: 457,769 km (0.081 R)
- M6: 575,802 km (0.09 R)
- M7: 658,530 km (0.098 R)
- M8: 763,548 km (0.104 R)
- M9: 945,159 km (0.096 R)
- M10: 1,010,982 km (0.096 R)
- M11: 1,147,715 km (0.084 R)
- M12: 1,247,197 km (0.112 R)
- M13: 1,500,915 km (0.102 R)
- M14: 1,602,343 km (0.104 R)
- M15: 1,861,746 km (0.044 R)
- M16: 2,117,109 km (0.074 R)
- M17: 2,275,832 km (0.09 R)
- M18: 2,502,922 km (0.103 R)
- M19: 2,567,847 km (0.118 R)
- M20: 2,737,342 km (0.091 R)
- M21: 3,018,137 km (0.042 R)
- M22: 3,298,184 km (0.075 R)
- M23: 3,472,316 km (0.091 R)
- M24: 3,808,463 km (0.099 R)
- M25: 4,432,884 km (0.111 R)
- M26: 4,489,133 km (0.101 R)
- M27: 4,557,050 km (0.072 R)
- M28: 4,889,906 km (0.103 R)
- M29: 5,242,657 km (0.113 R)
- M30: 5,518,815 km (0.078 R)
- M31: 5,591,520 km (0.035 R)
- M32: 6,097,609 km (0.036 R)
- M33: 6,210,705 km (0.113 R)
- M34: 6,477,139 km (0.102 R)
- M35: 6,682,836 km (0.088 R)
- M36: 6,890,478 km (0.109 R)
- M37: 7,153,321 km (0.102 R)
- M38: 7,486,326 km (0.115 R)
- M39: 7,892,634 km (0.113 R)
- M40: 7,947,387 km (0.098 R)
- M41: 8,306,123 km (0.049 R)
- M42: 8,741,004 km (0.107 R)
- M43: 9,255,171 km (0.088 R)
- M44: 9,443,216 km (0.119 R)
- M45: 9,588,775 km (0.113 R)
Planet 5 - Gas Giant
Semi-Major Axis: 1.5 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 518.7
Radius: 11.7
Gravity: 3.79 G
Time & Orbit
Eccentricity (e): 0.1
Orbit Range: 1.35 AU - 1.65 AU
Year: 1186 Days
Day: 7.8 Hours
Environment
Temp: -174 °C
Axial Tilt: 2.7 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (60)
Outer Limit: 33,849,878 km
- M1: 149,149 km (0.111 R)
- M2: 276,008 km (0.094 R)
- M3: 394,190 km (0.107 R)
- M4: 504,444 km (0.107 R)
- M5: 610,659 km (0.04 R)
- M6: 798,853 km (0.03 R)
- M7: 874,549 km (0.037 R)
- M8: 973,134 km (0.112 R)
- M9: 1,125,126 km (0.094 R)
- M10: 1,233,584 km (0.086 R)
- M11: 1,368,521 km (0.075 R)
- M12: 1,508,695 km (0.109 R)
- M13: 1,914,853 km (0.094 R)
- M14: 1,993,242 km (0.118 R)
- M15: 2,081,654 km (0.039 R)
- M16: 2,207,765 km (0.107 R)
- M17: 2,280,919 km (0.084 R)
- M18: 2,373,669 km (0.056 R)
- M19: 2,698,446 km (0.047 R)
- M20: 2,836,376 km (0.116 R)
- M21: 2,926,434 km (0.09 R)
- M22: 3,140,059 km (0.116 R)
- M23: 3,306,412 km (0.084 R)
- M24: 3,433,122 km (0.112 R)
- M25: 3,507,771 km (0.112 R)
- M26: 3,593,939 km (0.026 R)
- M27: 3,812,053 km (0.096 R)
- M28: 3,967,485 km (0.116 R)
- M29: 4,068,464 km (0.113 R)
- M30: 4,158,970 km (0.09 R)
- M31: 4,261,744 km (0.089 R)
- M32: 4,574,852 km (0.12 R)
- M33: 4,704,554 km (0.057 R)
- M34: 4,931,643 km (0.096 R)
- M35: 5,137,789 km (0.08 R)
- M36: 5,297,410 km (0.097 R)
- M37: 5,672,153 km (0.116 R)
- M38: 5,786,296 km (0.06 R)
- M39: 6,159,244 km (0.072 R)
- M40: 6,580,062 km (0.11 R)
- M41: 6,673,262 km (0.036 R)
- M42: 6,861,157 km (0.032 R)
- M43: 6,982,929 km (0.114 R)
- M44: 7,173,816 km (0.103 R)
- M45: 7,311,147 km (0.116 R)
- M46: 7,463,288 km (0.107 R)
- M47: 7,546,614 km (0.082 R)
- M48: 7,658,364 km (0.102 R)
- M49: 7,756,500 km (0.065 R)
- M50: 7,925,845 km (0.107 R)
- M51: 8,571,808 km (0.11 R)
- M52: 9,071,166 km (0.056 R)
- M53: 9,384,424 km (0.096 R)
- M54: 9,474,482 km (0.041 R)
- M55: 9,564,989 km (0.106 R)
- M56: 9,670,754 km (0.097 R)
- M57: 9,868,373 km (0.043 R)
- M58: 10,252,241 km (0.09 R)
- M59: 10,329,733 km (0.044 R)
- M60: 10,485,016 km (0.11 R)
Planet 6 - Gas Giant
Semi-Major Axis: 3.64 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 138.8
Radius: 9
Gravity: 1.71 G
Time & Orbit
Eccentricity (e): 0.24
Orbit Range: 2.77 AU - 4.51 AU
Year: 4484 Days
Day: 7.5 Hours
Environment
Temp: -200 °C
Axial Tilt: 3.1 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (61)
Outer Limit: 33,849,878 km
- M1: 112,498 km (0.104 R)
- M2: 258,056 km (0.069 R)
- M3: 364,869 km (0.116 R)
- M4: 468,840 km (0.104 R)
- M5: 599,139 km (0.067 R)
- M6: 685,308 km (0.038 R)
- M7: 801,396 km (0.089 R)
- M8: 1,111,512 km (0.061 R)
- M9: 1,373,308 km (0.098 R)
- M10: 1,599,201 km (0.115 R)
- M11: 1,733,690 km (0.113 R)
- M12: 1,860,250 km (0.096 R)
- M13: 2,086,292 km (0.072 R)
- M14: 2,208,962 km (0.039 R)
- M15: 2,346,592 km (0.083 R)
- M16: 2,551,990 km (0.109 R)
- M17: 2,630,679 km (0.102 R)
- M18: 2,925,686 km (0.09 R)
- M19: 3,008,114 km (0.109 R)
- M20: 3,474,859 km (0.089 R)
- M21: 3,635,527 km (0.075 R)
- M22: 4,055,748 km (0.102 R)
- M23: 4,225,093 km (0.082 R)
- M24: 4,475,669 km (0.111 R)
- M25: 4,634,692 km (0.105 R)
- M26: 4,827,972 km (0.061 R)
- M27: 5,289,631 km (0.115 R)
- M28: 5,542,601 km (0.117 R)
- M29: 6,219,232 km (0.11 R)
- M30: 6,450,511 km (0.1 R)
- M31: 6,540,269 km (0.111 R)
- M32: 7,087,498 km (0.106 R)
- M33: 7,273,149 km (0.116 R)
- M34: 7,385,348 km (0.08 R)
- M35: 7,441,596 km (0.101 R)
- M36: 7,668,387 km (0.084 R)
- M37: 7,839,826 km (0.064 R)
- M38: 8,070,506 km (0.113 R)
- M39: 8,264,534 km (0.07 R)
- M40: 8,577,942 km (0.111 R)
- M41: 8,657,079 km (0.063 R)
- M42: 8,815,803 km (0.114 R)
- M43: 9,953,644 km (0.076 R)
- M44: 10,245,360 km (0.114 R)
- M45: 10,371,321 km (0.091 R)
- M46: 11,094,328 km (0.034 R)
- M47: 11,353,431 km (0.104 R)
- M48: 12,098,279 km (0.113 R)
- M49: 12,476,762 km (0.075 R)
- M50: 12,633,690 km (0.113 R)
- M51: 13,040,147 km (0.074 R)
- M52: 13,336,501 km (0.095 R)
- M53: 13,635,098 km (0.111 R)
- M54: 13,704,362 km (0.07 R)
- M55: 13,889,414 km (0.091 R)
- M56: 14,238,875 km (0.109 R)
- M57: 14,496,931 km (0.066 R)
- M58: 15,089,189 km (0.095 R)
- M59: 15,280,375 km (0.112 R)
- M60: 15,955,810 km (0.098 R)
- M61: 16,053,198 km (0.085 R)
Planet 7 - Gas Giant
Semi-Major Axis: 3.71 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 635.9
Radius: 14.7
Gravity: 2.94 G
Time & Orbit
Eccentricity (e): 0.071
Orbit Range: 3.45 AU - 3.97 AU
Year: 4614 Days
Day: 12.3 Hours
Environment
Temp: -214 °C
Axial Tilt: 16.2 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (68)
Outer Limit: 33,849,878 km
- M1: 192,682 km (0.119 R)
- M2: 388,206 km (0.025 R)
- M3: 610,958 km (0.067 R)
- M4: 775,515 km (0.094 R)
- M5: 1,236,426 km (0.085 R)
- M6: 2,144,186 km (0.059 R)
- M7: 2,407,778 km (0.07 R)
- M8: 2,833,084 km (0.049 R)
- M9: 3,123,454 km (0.08 R)
- M10: 3,505,377 km (0.036 R)
- M11: 3,733,514 km (0.069 R)
- M12: 4,095,840 km (0.109 R)
- M13: 4,226,589 km (0.107 R)
- M14: 4,492,125 km (0.071 R)
- M15: 4,717,718 km (0.115 R)
- M16: 5,274,522 km (0.111 R)
- M17: 5,828,034 km (0.108 R)
- M18: 6,099,404 km (0.078 R)
- M19: 6,603,400 km (0.101 R)
- M20: 6,705,874 km (0.1 R)
- M21: 6,886,439 km (0.049 R)
- M22: 7,278,984 km (0.112 R)
- M23: 7,384,899 km (0.036 R)
- M24: 7,867,801 km (0.063 R)
- M25: 8,305,973 km (0.092 R)
- M26: 9,378,141 km (0.061 R)
- M27: 9,609,419 km (0.084 R)
- M28: 10,285,153 km (0.105 R)
- M29: 10,583,601 km (0.119 R)
- M30: 10,703,877 km (0.067 R)
- M31: 10,945,777 km (0.05 R)
- M32: 11,158,954 km (0.095 R)
- M33: 11,404,145 km (0.118 R)
- M34: 11,931,328 km (0.096 R)
- M35: 12,056,541 km (0.117 R)
- M36: 12,498,154 km (0.105 R)
- M37: 12,721,055 km (0.08 R)
- M38: 12,977,316 km (0.101 R)
- M39: 13,235,372 km (0.095 R)
- M40: 13,527,687 km (0.096 R)
- M41: 13,723,809 km (0.036 R)
- M42: 13,822,245 km (0.095 R)
- M43: 13,986,803 km (0.03 R)
- M44: 14,384,284 km (0.068 R)
- M45: 14,684,976 km (0.055 R)
- M46: 15,428,477 km (0.033 R)
- M47: 15,839,273 km (0.106 R)
- M48: 16,011,610 km (0.107 R)
- M49: 17,022,891 km (0.096 R)
- M50: 17,270,027 km (0.084 R)
- M51: 17,803,792 km (0.081 R)
- M52: 18,343,093 km (0.093 R)
- M53: 18,560,159 km (0.111 R)
- M54: 19,955,608 km (0.084 R)
- M55: 20,104,458 km (0.119 R)
- M56: 20,515,702 km (0.107 R)
- M57: 20,892,091 km (0.062 R)
- M58: 21,270,573 km (0.106 R)
- M59: 22,188,506 km (0.116 R)
- M60: 23,080,259 km (0.118 R)
- M61: 23,589,639 km (0.115 R)
- M62: 24,380,264 km (0.11 R)
- M63: 24,619,172 km (0.041 R)
- M64: 25,542,340 km (0.104 R)
- M65: 25,906,611 km (0.115 R)
- M66: 26,313,368 km (0.059 R)
- M67: 27,753,846 km (0.118 R)
- M68: 27,878,461 km (0.106 R)
Planet 8 - Gas Giant
Semi-Major Axis: 4.34 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 51.8
Radius: 14.3
Gravity: 0.25 G
Time & Orbit
Eccentricity (e): 0.171
Orbit Range: 3.6 AU - 5.08 AU
Year: 5838 Days
Day: 6.3 Hours
Environment
Temp: -222 °C
Axial Tilt: 11.9 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (41)
Outer Limit: 33,849,878 km
- M1: 181,313 km (0.1 R)
- M2: 343,626 km (0.08 R)
- M3: 453,581 km (0.077 R)
- M4: 593,754 km (0.083 R)
- M5: 701,913 km (0.111 R)
- M6: 871,258 km (0.104 R)
- M7: 1,072,617 km (0.112 R)
- M8: 1,418,936 km (0.045 R)
- M9: 1,552,228 km (0.093 R)
- M10: 1,650,065 km (0.037 R)
- M11: 1,852,470 km (0.094 R)
- M12: 2,626,041 km (0.117 R)
- M13: 2,876,468 km (0.067 R)
- M14: 3,172,522 km (0.118 R)
- M15: 3,661,707 km (0.106 R)
- M16: 3,754,458 km (0.088 R)
- M17: 3,956,116 km (0.114 R)
- M18: 4,092,399 km (0.041 R)
- M19: 4,230,478 km (0.077 R)
- M20: 4,426,302 km (0.073 R)
- M21: 4,568,121 km (0.114 R)
- M22: 4,682,563 km (0.084 R)
- M23: 4,841,585 km (0.083 R)
- M24: 4,958,421 km (0.102 R)
- M25: 5,091,115 km (0.091 R)
- M26: 5,329,723 km (0.111 R)
- M27: 5,480,817 km (0.065 R)
- M28: 5,617,998 km (0.05 R)
- M29: 6,115,262 km (0.106 R)
- M30: 6,626,737 km (0.116 R)
- M31: 7,913,727 km (0.055 R)
- M32: 8,086,513 km (0.071 R)
- M33: 8,790,371 km (0.116 R)
- M34: 9,077,449 km (0.109 R)
- M35: 9,458,924 km (0.074 R)
- M36: 9,957,234 km (0.069 R)
- M37: 10,521,069 km (0.025 R)
- M38: 12,015,252 km (0.058 R)
- M39: 12,174,424 km (0.069 R)
- M40: 13,245,844 km (0.072 R)
- M41: 13,348,468 km (0.084 R)
Planet 9 - Ice Giant
Semi-Major Axis: 6.09 AU
Status: Outer (Cold)
Composition: Methane/Ammonia Ices
Physical Data
Mass: 256.2
Radius: 4.5
Gravity: 12.65 G
Time & Orbit
Eccentricity (e): 0.126
Orbit Range: 5.32 AU - 6.86 AU
Year: 9704 Days
Day: 22 Hours
Environment
Temp: -225 °C
Axial Tilt: 29.8 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (90)
Outer Limit: 33,849,878 km
- M1: 64,477 km (0.039 R)
- M2: 111,899 km (0.109 R)
- M3: 422,464 km (0.058 R)
- M4: 491,878 km (0.043 R)
- M5: 722,558 km (0.091 R)
- M6: 1,014,423 km (0.108 R)
- M7: 1,391,111 km (0.117 R)
- M8: 1,460,823 km (0.11 R)
- M9: 1,549,385 km (0.097 R)
- M10: 1,658,292 km (0.116 R)
- M11: 1,788,443 km (0.117 R)
- M12: 1,864,289 km (0.04 R)
- M13: 1,921,884 km (0.099 R)
- M14: 2,078,363 km (0.096 R)
- M15: 2,118,156 km (0.058 R)
- M16: 2,218,836 km (0.112 R)
- M17: 2,362,300 km (0.104 R)
- M18: 2,551,242 km (0.075 R)
- M19: 2,744,971 km (0.098 R)
- M20: 3,124,052 km (0.109 R)
- M21: 3,261,682 km (0.046 R)
- M22: 3,401,407 km (0.036 R)
- M23: 3,472,017 km (0.075 R)
- M24: 3,881,167 km (0.051 R)
- M25: 4,254,863 km (0.077 R)
- M26: 4,823,484 km (0.053 R)
- M27: 5,062,990 km (0.055 R)
- M28: 5,333,613 km (0.046 R)
- M29: 5,832,522 km (0.091 R)
- M30: 5,888,771 km (0.053 R)
- M31: 6,520,672 km (0.09 R)
- M32: 6,755,690 km (0.097 R)
- M33: 6,933,861 km (0.087 R)
- M34: 7,385,946 km (0.04 R)
- M35: 7,446,832 km (0.064 R)
- M36: 7,754,406 km (0.061 R)
- M37: 7,785,372 km (0.086 R)
- M38: 8,509,276 km (0.078 R)
- M39: 8,733,823 km (0.072 R)
- M40: 9,684,667 km (0.103 R)
- M41: 10,020,215 km (0.054 R)
- M42: 11,329,346 km (0.065 R)
- M43: 11,399,807 km (0.068 R)
- M44: 11,611,787 km (0.067 R)
- M45: 11,718,300 km (0.092 R)
- M46: 11,789,509 km (0.119 R)
- M47: 12,327,912 km (0.107 R)
- M48: 12,545,577 km (0.119 R)
- M49: 13,169,101 km (0.091 R)
- M50: 13,206,051 km (0.113 R)
- M51: 13,840,197 km (0.11 R)
- M52: 14,179,933 km (0.098 R)
- M53: 14,637,104 km (0.068 R)
- M54: 15,683,542 km (0.083 R)
- M55: 15,879,964 km (0.102 R)
- M56: 16,275,201 km (0.093 R)
- M57: 16,394,431 km (0.07 R)
- M58: 16,753,765 km (0.104 R)
- M59: 16,874,041 km (0.117 R)
- M60: 17,970,295 km (0.108 R)
- M61: 18,093,563 km (0.099 R)
- M62: 18,216,982 km (0.076 R)
- M63: 18,672,208 km (0.104 R)
- M64: 18,838,710 km (0.117 R)
- M65: 18,880,448 km (0.057 R)
- M66: 19,593,880 km (0.093 R)
- M67: 19,720,739 km (0.096 R)
- M68: 20,017,691 km (0.085 R)
- M69: 20,701,952 km (0.044 R)
- M70: 21,003,840 km (0.064 R)
- M71: 21,307,075 km (0.082 R)
- M72: 21,350,608 km (0.096 R)
- M73: 21,481,057 km (0.106 R)
- M74: 23,335,772 km (0.074 R)
- M75: 23,604,898 km (0.119 R)
- M76: 24,418,561 km (0.11 R)
- M77: 24,509,517 km (0.075 R)
- M78: 24,874,386 km (0.083 R)
- M79: 25,103,420 km (0.06 R)
- M80: 25,333,203 km (0.092 R)
- M81: 25,794,712 km (0.085 R)
- M82: 26,119,489 km (0.044 R)
- M83: 26,305,589 km (0.058 R)
- M84: 26,772,933 km (0.11 R)
- M85: 27,810,693 km (0.092 R)
- M86: 28,717,555 km (0.116 R)
- M87: 31,149,867 km (0.093 R)
- M88: 32,790,956 km (0.06 R)
- M89: 33,546,126 km (0.085 R)
- M90: 33,849,809 km (0.113 R)
Kuiper Belt
Range: 30 - 48 AU
Composition
Type: Dwarf Planets/TNOs (Ices)
Reservoir of dwarf planets and volatile ices.
Outer System
Oort Cloud
Range: 182 - 10,616 AU
Composition
Type: Cometary Reservoir
System's final boundary, containing trillions of icy planetesimals.