G3V Star System Generated (Seed: 1767369141)
Star Details
Spectral Class: G5V
Temperature: 5,600 K
Mass: 1 sol
Luminosity: 1 lux
Habitable Zone (HZ)
Inner Boundary: 0.95 AU
Outer Boundary: 1.37 AU
Physical Limits
Snow Line: 4.8 AU
Max System Radius: 20 AU
Planetary System (8 Planets)
Planet 1 - Terrestrial
Semi-Major Axis: 0.75 AU
Status: Inner (Hot)
Composition: Rocky (Silicates/Metals)
Physical Data
Mass: 2.03
Radius: 1.33
Gravity: 1.15 G
Time & Orbit
Eccentricity (e): 0.175
Orbit Range: 0.62 AU - 0.88 AU
Year: 237 Days
Day: 43 Hours
Environment
Temp: 104 °C
Axial Tilt: 2.7 °
Atmosphere: Dense COâ‚‚
Biome: Volcanic/Barren
Planet 2 - Terrestrial
Semi-Major Axis: 2.15 AU
Status: Outer (Cold)
Composition: Rocky (Silicates/Metals)
Physical Data
Mass: 2.15
Radius: 1.36
Gravity: 1.16 G
Time & Orbit
Eccentricity (e): 0.195
Orbit Range: 1.73 AU - 2.57 AU
Year: 1151 Days
Day: 19.6 Hours
Environment
Temp: -82 °C
Axial Tilt: 25.6 °
Atmosphere: Thin Nâ‚‚/CHâ‚„
Biome: Ice Cap/Desert
Planet 3 - Terrestrial
Semi-Major Axis: 4.62 AU
Status: Outer (Cold)
Composition: Rocky (Silicates/Metals)
Physical Data
Mass: 1.27
Radius: 1.1
Gravity: 1.05 G
Time & Orbit
Eccentricity (e): 0.006
Orbit Range: 4.59 AU - 4.65 AU
Year: 3627 Days
Day: 29.5 Hours
Environment
Temp: -142 °C
Axial Tilt: 10.8 °
Atmosphere: Thin Nâ‚‚/CHâ‚„
Biome: Ice Cap/Desert
Satellites (1)
Outer Limit: 51,137,252 km
- M1: 603,927 km (0.112 R)
Planet 4 - Gas Giant
Semi-Major Axis: 5.52 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 459.4
Radius: 10.7
Gravity: 4.01 G
Time & Orbit
Eccentricity (e): 0.098
Orbit Range: 4.98 AU - 6.06 AU
Year: 4737 Days
Day: 7.1 Hours
Environment
Temp: -150 °C
Axial Tilt: 38.2 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (77)
Outer Limit: 51,137,252 km
- M1: 141,968 km (0.031 R)
- M2: 227,389 km (0.104 R)
- M3: 313,557 km (0.077 R)
- M4: 425,157 km (0.049 R)
- M5: 717,771 km (0.117 R)
- M6: 829,371 km (0.025 R)
- M7: 996,023 km (0.105 R)
- M8: 1,070,971 km (0.052 R)
- M9: 1,174,194 km (0.105 R)
- M10: 1,335,610 km (0.08 R)
- M11: 1,562,550 km (0.12 R)
- M12: 1,833,023 km (0.095 R)
- M13: 2,005,808 km (0.091 R)
- M14: 2,608,837 km (0.085 R)
- M15: 2,967,274 km (0.103 R)
- M16: 3,077,827 km (0.107 R)
- M17: 3,360,567 km (0.089 R)
- M18: 3,651,834 km (0.111 R)
- M19: 3,810,557 km (0.071 R)
- M20: 4,032,560 km (0.052 R)
- M21: 4,745,693 km (0.1 R)
- M22: 4,875,694 km (0.085 R)
- M23: 5,161,276 km (0.066 R)
- M24: 5,339,746 km (0.101 R)
- M25: 5,543,050 km (0.096 R)
- M26: 5,611,416 km (0.112 R)
- M27: 5,771,935 km (0.083 R)
- M28: 6,027,298 km (0.109 R)
- M29: 6,333,974 km (0.118 R)
- M30: 6,573,480 km (0.067 R)
- M31: 7,234,703 km (0.065 R)
- M32: 7,409,583 km (0.054 R)
- M33: 7,763,681 km (0.056 R)
- M34: 8,020,091 km (0.079 R)
- M35: 8,227,135 km (0.049 R)
- M36: 8,305,225 km (0.061 R)
- M37: 8,462,303 km (0.035 R)
- M38: 8,620,278 km (0.092 R)
- M39: 9,046,333 km (0.087 R)
- M40: 9,126,966 km (0.056 R)
- M41: 9,424,815 km (0.064 R)
- M42: 9,863,736 km (0.101 R)
- M43: 10,225,314 km (0.053 R)
- M44: 10,619,654 km (0.052 R)
- M45: 10,704,775 km (0.054 R)
- M46: 10,847,192 km (0.061 R)
- M47: 11,510,359 km (0.091 R)
- M48: 12,305,622 km (0.12 R)
- M49: 12,815,601 km (0.084 R)
- M50: 13,118,686 km (0.101 R)
- M51: 13,271,126 km (0.071 R)
- M52: 14,323,547 km (0.088 R)
- M53: 14,669,866 km (0.079 R)
- M54: 14,796,426 km (0.074 R)
- M55: 15,146,336 km (0.118 R)
- M56: 15,274,391 km (0.116 R)
- M57: 16,180,057 km (0.117 R)
- M58: 16,804,628 km (0.113 R)
- M59: 16,903,961 km (0.103 R)
- M60: 17,571,168 km (0.104 R)
- M61: 17,874,253 km (0.036 R)
- M62: 18,965,868 km (0.104 R)
- M63: 19,034,833 km (0.092 R)
- M64: 19,207,469 km (0.117 R)
- M65: 19,554,536 km (0.079 R)
- M66: 19,728,818 km (0.117 R)
- M67: 19,973,709 km (0.089 R)
- M68: 20,466,485 km (0.066 R)
- M69: 20,856,486 km (0.04 R)
- M70: 22,041,152 km (0.112 R)
- M71: 22,295,319 km (0.037 R)
- M72: 22,586,885 km (0.071 R)
- M73: 22,806,345 km (0.11 R)
- M74: 24,550,507 km (0.098 R)
- M75: 24,813,948 km (0.032 R)
- M76: 25,002,741 km (0.111 R)
- M77: 25,191,982 km (0.112 R)
Planet 5 - Gas Giant
Semi-Major Axis: 5.54 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 994.8
Radius: 13.7
Gravity: 5.3 G
Time & Orbit
Eccentricity (e): 0.154
Orbit Range: 4.69 AU - 6.39 AU
Year: 4763 Days
Day: 5.5 Hours
Environment
Temp: -150 °C
Axial Tilt: 48.6 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (81)
Outer Limit: 51,137,252 km
- M1: 189,690 km (0.101 R)
- M2: 324,627 km (0.093 R)
- M3: 516,711 km (0.067 R)
- M4: 654,341 km (0.114 R)
- M5: 874,100 km (0.107 R)
- M6: 1,059,602 km (0.113 R)
- M7: 1,591,123 km (0.115 R)
- M8: 1,731,895 km (0.055 R)
- M9: 1,970,054 km (0.1 R)
- M10: 2,317,720 km (0.103 R)
- M11: 2,458,491 km (0.107 R)
- M12: 2,984,478 km (0.101 R)
- M13: 3,339,772 km (0.067 R)
- M14: 3,522,581 km (0.076 R)
- M15: 3,708,830 km (0.092 R)
- M16: 3,826,863 km (0.07 R)
- M17: 4,311,859 km (0.102 R)
- M18: 4,411,192 km (0.062 R)
- M19: 4,511,423 km (0.107 R)
- M20: 4,688,547 km (0.095 R)
- M21: 4,893,945 km (0.114 R)
- M22: 5,447,307 km (0.08 R)
- M23: 5,555,018 km (0.05 R)
- M24: 6,413,710 km (0.027 R)
- M25: 6,498,980 km (0.061 R)
- M26: 7,048,304 km (0.116 R)
- M27: 7,612,587 km (0.064 R)
- M28: 8,068,561 km (0.119 R)
- M29: 9,230,937 km (0.119 R)
- M30: 9,424,367 km (0.074 R)
- M31: 9,619,143 km (0.062 R)
- M32: 9,815,415 km (0.115 R)
- M33: 10,411,862 km (0.092 R)
- M34: 10,647,030 km (0.065 R)
- M35: 10,850,034 km (0.099 R)
- M36: 11,432,120 km (0.087 R)
- M37: 11,640,061 km (0.085 R)
- M38: 11,779,336 km (0.08 R)
- M39: 12,059,683 km (0.039 R)
- M40: 12,913,737 km (0.082 R)
- M41: 13,130,355 km (0.109 R)
- M42: 13,457,525 km (0.054 R)
- M43: 14,157,194 km (0.07 R)
- M44: 14,417,794 km (0.094 R)
- M45: 14,567,541 km (0.1 R)
- M46: 16,365,259 km (0.088 R)
- M47: 17,270,326 km (0.113 R)
- M48: 17,389,556 km (0.12 R)
- M49: 17,509,084 km (0.038 R)
- M50: 18,110,767 km (0.084 R)
- M51: 18,312,874 km (0.085 R)
- M52: 18,556,419 km (0.063 R)
- M53: 19,128,781 km (0.118 R)
- M54: 19,293,488 km (0.106 R)
- M55: 19,707,126 km (0.114 R)
- M56: 20,923,057 km (0.061 R)
- M57: 21,050,365 km (0.109 R)
- M58: 21,561,691 km (0.083 R)
- M59: 22,033,971 km (0.079 R)
- M60: 22,163,373 km (0.086 R)
- M61: 23,076,369 km (0.07 R)
- M62: 23,691,815 km (0.067 R)
- M63: 23,780,227 km (0.119 R)
- M64: 24,001,632 km (0.092 R)
- M65: 24,268,215 km (0.088 R)
- M66: 25,164,007 km (0.105 R)
- M67: 26,253,230 km (0.101 R)
- M68: 27,543,362 km (0.098 R)
- M69: 27,636,262 km (0.077 R)
- M70: 27,869,186 km (0.054 R)
- M71: 28,102,708 km (0.119 R)
- M72: 28,289,855 km (0.075 R)
- M73: 28,383,653 km (0.1 R)
- M74: 29,898,331 km (0.115 R)
- M75: 30,185,260 km (0.089 R)
- M76: 30,377,044 km (0.062 R)
- M77: 31,003,112 km (0.066 R)
- M78: 31,148,221 km (0.1 R)
- M79: 32,121,356 km (0.028 R)
- M80: 32,759,091 km (0.087 R)
- M81: 33,104,363 km (0.111 R)
Planet 6 - Gas Giant
Semi-Major Axis: 9.25 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 469.1
Radius: 13
Gravity: 2.78 G
Time & Orbit
Eccentricity (e): 0.197
Orbit Range: 7.43 AU - 11.07 AU
Year: 10275 Days
Day: 5.1 Hours
Environment
Temp: -165 °C
Axial Tilt: 34.3 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (72)
Outer Limit: 51,137,252 km
- M1: 256,710 km (0.053 R)
- M2: 351,854 km (0.082 R)
- M3: 543,788 km (0.056 R)
- M4: 791,522 km (0.073 R)
- M5: 1,205,160 km (0.079 R)
- M6: 1,377,198 km (0.104 R)
- M7: 1,537,417 km (0.116 R)
- M8: 2,503,820 km (0.11 R)
- M9: 3,599,774 km (0.103 R)
- M10: 4,345,369 km (0.12 R)
- M11: 4,584,427 km (0.07 R)
- M12: 5,075,557 km (0.032 R)
- M13: 5,264,199 km (0.091 R)
- M14: 5,519,264 km (0.118 R)
- M15: 6,717,244 km (0.07 R)
- M16: 6,924,586 km (0.101 R)
- M17: 8,509,426 km (0.085 R)
- M18: 8,696,423 km (0.08 R)
- M19: 10,201,677 km (0.098 R)
- M20: 11,167,631 km (0.078 R)
- M21: 11,578,875 km (0.119 R)
- M22: 11,911,431 km (0.091 R)
- M23: 13,708,401 km (0.108 R)
- M24: 13,971,992 km (0.116 R)
- M25: 14,060,255 km (0.094 R)
- M26: 15,043,263 km (0.083 R)
- M27: 16,839,933 km (0.072 R)
- M28: 17,311,466 km (0.108 R)
- M29: 18,315,866 km (0.111 R)
- M30: 18,654,854 km (0.101 R)
- M31: 19,290,047 km (0.104 R)
- M32: 20,081,420 km (0.114 R)
- M33: 20,984,542 km (0.06 R)
- M34: 21,849,667 km (0.098 R)
- M35: 22,003,603 km (0.073 R)
- M36: 22,157,838 km (0.076 R)
- M37: 23,509,605 km (0.083 R)
- M38: 24,142,404 km (0.088 R)
- M39: 24,620,818 km (0.086 R)
- M40: 24,727,481 km (0.088 R)
- M41: 24,995,111 km (0.056 R)
- M42: 25,317,345 km (0.04 R)
- M43: 26,729,699 km (0.085 R)
- M44: 27,224,568 km (0.095 R)
- M45: 27,390,323 km (0.116 R)
- M46: 27,611,578 km (0.095 R)
- M47: 28,335,183 km (0.111 R)
- M48: 28,503,032 km (0.091 R)
- M49: 29,290,814 km (0.114 R)
- M50: 29,801,093 km (0.1 R)
- M51: 30,371,360 km (0.108 R)
- M52: 30,485,802 km (0.077 R)
- M53: 31,118,152 km (0.111 R)
- M54: 31,349,281 km (0.075 R)
- M55: 32,982,291 km (0.074 R)
- M56: 33,453,973 km (0.082 R)
- M57: 33,631,397 km (0.103 R)
- M58: 33,809,119 km (0.071 R)
- M59: 34,822,495 km (0.117 R)
- M60: 34,942,323 km (0.07 R)
- M61: 35,423,130 km (0.072 R)
- M62: 35,906,182 km (0.089 R)
- M63: 37,000,939 km (0.111 R)
- M64: 37,798,445 km (0.07 R)
- M65: 38,849,969 km (0.074 R)
- M66: 39,347,980 km (0.094 R)
- M67: 39,785,703 km (0.116 R)
- M68: 39,910,917 km (0.075 R)
- M69: 41,806,621 km (0.081 R)
- M70: 41,934,078 km (0.072 R)
- M71: 42,317,049 km (0.082 R)
- M72: 42,508,983 km (0.03 R)
Planet 7 - Gas Giant
Semi-Major Axis: 11.46 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 772
Radius: 14.6
Gravity: 3.62 G
Time & Orbit
Eccentricity (e): 0.132
Orbit Range: 9.95 AU - 12.97 AU
Year: 14170 Days
Day: 5.6 Hours
Environment
Temp: -173 °C
Axial Tilt: 28.2 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (87)
Outer Limit: 51,137,252 km
- M1: 183,557 km (0.088 R)
- M2: 444,605 km (0.096 R)
- M3: 800,648 km (0.047 R)
- M4: 1,548,488 km (0.112 R)
- M5: 2,533,440 km (0.075 R)
- M6: 2,628,584 km (0.063 R)
- M7: 2,725,075 km (0.091 R)
- M8: 3,021,428 km (0.026 R)
- M9: 3,328,702 km (0.108 R)
- M10: 3,610,395 km (0.059 R)
- M11: 3,826,863 km (0.108 R)
- M12: 4,122,319 km (0.114 R)
- M13: 4,348,960 km (0.071 R)
- M14: 5,668,114 km (0.119 R)
- M15: 5,878,299 km (0.098 R)
- M16: 6,480,729 km (0.112 R)
- M17: 8,072,152 km (0.071 R)
- M18: 8,789,922 km (0.114 R)
- M19: 9,528,337 km (0.047 R)
- M20: 9,678,384 km (0.115 R)
- M21: 10,543,658 km (0.087 R)
- M22: 10,751,001 km (0.068 R)
- M23: 11,116,917 km (0.092 R)
- M24: 11,275,042 km (0.116 R)
- M25: 13,285,787 km (0.118 R)
- M26: 13,622,382 km (0.108 R)
- M27: 14,018,517 km (0.105 R)
- M28: 14,132,361 km (0.062 R)
- M29: 14,361,096 km (0.088 R)
- M30: 14,996,289 km (0.041 R)
- M31: 15,936,811 km (0.088 R)
- M32: 16,294,350 km (0.094 R)
- M33: 16,414,178 km (0.098 R)
- M34: 17,261,051 km (0.12 R)
- M35: 17,383,123 km (0.09 R)
- M36: 17,998,120 km (0.069 R)
- M37: 18,871,173 km (0.11 R)
- M38: 21,572,462 km (0.097 R)
- M39: 22,299,807 km (0.117 R)
- M40: 23,642,747 km (0.119 R)
- M41: 23,914,566 km (0.11 R)
- M42: 24,119,066 km (0.061 R)
- M43: 24,598,378 km (0.061 R)
- M44: 24,942,752 km (0.109 R)
- M45: 25,080,981 km (0.059 R)
- M46: 25,288,772 km (0.115 R)
- M47: 26,688,559 km (0.116 R)
- M48: 29,271,217 km (0.073 R)
- M49: 31,185,621 km (0.107 R)
- M50: 32,007,811 km (0.061 R)
- M51: 32,912,728 km (0.093 R)
- M52: 33,216,262 km (0.102 R)
- M53: 34,670,803 km (0.086 R)
- M54: 36,302,466 km (0.119 R)
- M55: 36,616,024 km (0.098 R)
- M56: 36,851,939 km (0.079 R)
- M57: 38,197,722 km (0.059 R)
- M58: 38,357,193 km (0.072 R)
- M59: 38,596,699 km (0.096 R)
- M60: 40,044,208 km (0.099 R)
- M61: 41,182,349 km (0.057 R)
- M62: 42,166,254 km (0.105 R)
- M63: 43,906,825 km (0.101 R)
- M64: 44,324,802 km (0.101 R)
- M65: 44,743,975 km (0.098 R)
- M66: 45,248,718 km (0.111 R)
- M67: 45,840,079 km (0.119 R)
- M68: 46,179,068 km (0.075 R)
- M69: 47,030,429 km (0.091 R)
- M70: 47,715,138 km (0.05 R)
- M71: 48,316,971 km (0.062 R)
- M72: 49,615,181 km (0.078 R)
- M73: 50,487,037 km (0.055 R)
- M74: 51,100,389 km (0.082 R)
- M75: 51,980,772 km (0.112 R)
- M76: 52,866,242 km (0.08 R)
- M77: 53,578,178 km (0.1 R)
- M78: 54,382,865 km (0.074 R)
- M79: 55,011,625 km (0.114 R)
- M80: 55,552,421 km (0.111 R)
- M81: 57,550,301 km (0.079 R)
- M82: 58,191,029 km (0.053 R)
- M83: 59,110,307 km (0.116 R)
- M84: 61,149,626 km (0.086 R)
- M85: 61,242,825 km (0.11 R)
- M86: 62,459,355 km (0.092 R)
- M87: 62,741,347 km (0.062 R)
Planet 8 - Gas Giant
Semi-Major Axis: 12.34 AU
Status: Outer (Cold)
Composition: Hydrogen/Helium Atmosphere
Physical Data
Mass: 331.8
Radius: 9.6
Gravity: 3.6 G
Time & Orbit
Eccentricity (e): 0.242
Orbit Range: 9.35 AU - 15.33 AU
Year: 15833 Days
Day: 8.8 Hours
Environment
Temp: -180 °C
Axial Tilt: 12.1 °
Atmosphere: Hâ‚‚, CHâ‚„
Biome: None
Satellites (84)
Outer Limit: 51,137,252 km
- M1: 137,480 km (0.077 R)
- M2: 497,263 km (0.098 R)
- M3: 590,313 km (0.112 R)
- M4: 672,742 km (0.112 R)
- M5: 813,663 km (0.045 R)
- M6: 1,064,239 km (0.09 R)
- M7: 1,295,518 km (0.113 R)
- M8: 1,757,027 km (0.098 R)
- M9: 2,240,228 km (0.104 R)
- M10: 2,455,799 km (0.101 R)
- M11: 2,936,307 km (0.066 R)
- M12: 3,695,367 km (0.119 R)
- M13: 4,244,989 km (0.054 R)
- M14: 4,512,470 km (0.054 R)
- M15: 5,528,090 km (0.05 R)
- M16: 6,844,103 km (0.118 R)
- M17: 7,396,568 km (0.084 R)
- M18: 8,210,829 km (0.104 R)
- M19: 8,628,506 km (0.114 R)
- M20: 9,096,149 km (0.099 R)
- M21: 9,571,870 km (0.109 R)
- M22: 9,923,126 km (0.036 R)
- M23: 10,100,250 km (0.081 R)
- M24: 10,592,876 km (0.1 R)
- M25: 10,819,367 km (0.102 R)
- M26: 11,601,614 km (0.079 R)
- M27: 11,835,136 km (0.099 R)
- M28: 12,259,396 km (0.071 R)
- M29: 12,354,391 km (0.106 R)
- M30: 12,497,257 km (0.103 R)
- M31: 13,660,230 km (0.069 R)
- M32: 15,315,232 km (0.091 R)
- M33: 15,777,489 km (0.099 R)
- M34: 16,348,803 km (0.068 R)
- M35: 16,505,731 km (0.029 R)
- M36: 16,821,233 km (0.049 R)
- M37: 17,351,408 km (0.053 R)
- M38: 17,725,702 km (0.103 R)
- M39: 18,156,993 km (0.097 R)
- M40: 19,637,563 km (0.085 R)
- M41: 19,748,714 km (0.069 R)
- M42: 20,083,664 km (0.12 R)
- M43: 21,499,159 km (0.089 R)
- M44: 22,771,339 km (0.102 R)
- M45: 25,025,779 km (0.106 R)
- M46: 25,086,067 km (0.088 R)
- M47: 25,935,035 km (0.075 R)
- M48: 26,179,328 km (0.105 R)
- M49: 26,547,189 km (0.076 R)
- M50: 26,793,427 km (0.119 R)
- M51: 27,598,862 km (0.072 R)
- M52: 28,727,279 km (0.07 R)
- M53: 29,615,292 km (0.111 R)
- M54: 29,870,656 km (0.056 R)
- M55: 29,998,562 km (0.104 R)
- M56: 30,255,122 km (0.101 R)
- M57: 31,093,618 km (0.064 R)
- M58: 31,809,145 km (0.117 R)
- M59: 32,793,648 km (0.101 R)
- M60: 32,859,621 km (0.036 R)
- M61: 32,991,716 km (0.115 R)
- M62: 33,588,312 km (0.095 R)
- M63: 34,188,649 km (0.076 R)
- M64: 34,792,426 km (0.083 R)
- M65: 35,535,179 km (0.11 R)
- M66: 36,010,451 km (0.099 R)
- M67: 36,283,168 km (0.043 R)
- M68: 36,624,850 km (0.104 R)
- M69: 36,830,397 km (0.106 R)
- M70: 37,656,327 km (0.114 R)
- M71: 38,836,954 km (0.052 R)
- M72: 38,906,666 km (0.079 R)
- M73: 40,807,756 km (0.104 R)
- M74: 43,172,001 km (0.12 R)
- M75: 43,316,662 km (0.075 R)
- M76: 43,606,583 km (0.053 R)
- M77: 43,897,251 km (0.066 R)
- M78: 44,553,238 km (0.104 R)
- M79: 45,801,482 km (0.106 R)
- M80: 46,244,741 km (0.114 R)
- M81: 46,318,792 km (0.041 R)
- M82: 48,708,020 km (0.084 R)
- M83: 50,145,655 km (0.059 R)
- M84: 50,221,651 km (0.106 R)
Kuiper Belt
Range: 30 - 59 AU
Composition
Type: Dwarf Planets/TNOs (Ices)
Reservoir of dwarf planets and volatile ices.
Outer System
Oort Cloud
Range: 248 - 14,441 AU
Composition
Type: Cometary Reservoir
System's final boundary, containing trillions of icy planetesimals.