🌌 Stone's Star System Generator

Asteroid Belt

Center: 0.32 AU

Composition

Type: Inner (Rocky/Metallic)

A dense region of planetesimals and debris.

Boundary

Planet 1 - Gas Giant

Semi-Major Axis: 0.63 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 551.7

Radius: 12.8

Gravity: 3.37 G

Time & Orbit

Eccentricity (e): 0.121

Orbit Range: 0.55 AU - 0.71 AU

Year: 339 Days

Day: 6.1 Hours

Environment

Temp: -142 °C

Axial Tilt: 37.7 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (35)

Outer Limit: 33,098,770 km

• M1: 164,408 km (0.114 R)
• M2: 308,321 km (0.092 R)
• M3: 388,057 km (0.064 R)
• M4: 498,161 km (0.025 R)
• M5: 593,604 km (0.111 R)
• M6: 673,340 km (0.036 R)
• M7: 788,830 km (0.095 R)
• M8: 886,068 km (0.107 R)
• M9: 983,905 km (0.101 R)
• M10: 1,073,814 km (0.096 R)
• M11: 1,301,053 km (0.111 R)
• M12: 1,463,067 km (0.117 R)
• M13: 1,581,100 km (0.099 R)
• M14: 1,697,936 km (0.05 R)
• M15: 1,788,592 km (0.101 R)
• M16: 1,935,348 km (0.051 R)
• M17: 2,035,429 km (0.066 R)
• M18: 2,127,132 km (0.083 R)
• M19: 2,267,455 km (0.115 R)
• M20: 2,362,599 km (0.103 R)
• M21: 2,448,468 km (0.116 R)
• M22: 2,562,761 km (0.041 R)
• M23: 2,678,999 km (0.107 R)
• M24: 2,870,933 km (0.076 R)
• M25: 2,974,305 km (0.11 R)
• M26: 3,067,355 km (0.034 R)
• M27: 3,292,350 km (0.079 R)
• M28: 3,431,326 km (0.093 R)
• M29: 3,603,065 km (0.114 R)
• M30: 3,733,813 km (0.07 R)
• M31: 3,828,210 km (0.084 R)
• M32: 3,923,354 km (0.118 R)
• M33: 4,181,111 km (0.106 R)
• M34: 4,431,239 km (0.081 R)
• M35: 4,591,757 km (0.073 R)

Planet 2 - Gas Giant

Semi-Major Axis: 0.64 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 968.2

Radius: 9.1

Gravity: 11.69 G

Time & Orbit

Eccentricity (e): 0.011

Orbit Range: 0.63 AU - 0.65 AU

Year: 347 Days

Day: 6.5 Hours

Environment

Temp: -145 °C

Axial Tilt: 15.6 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (50)

Outer Limit: 33,098,770 km

• M1: 113,694 km (0.062 R)
• M2: 177,872 km (0.109 R)
• M3: 235,467 km (0.073 R)
• M4: 301,440 km (0.11 R)
• M5: 391,498 km (0.082 R)
• M6: 458,966 km (0.106 R)
• M7: 517,010 km (0.115 R)
• M8: 585,376 km (0.094 R)
• M9: 692,339 km (0.092 R)
• M10: 870,211 km (0.102 R)
• M11: 944,711 km (0.055 R)
• M12: 1,044,642 km (0.062 R)
• M13: 1,138,739 km (0.104 R)
• M14: 1,211,144 km (0.046 R)
• M15: 1,275,322 km (0.093 R)
• M16: 1,366,128 km (0.037 R)
• M17: 1,538,315 km (0.055 R)
• M18: 1,619,098 km (0.069 R)
• M19: 1,679,236 km (0.091 R)
• M20: 1,773,632 km (0.106 R)
• M21: 1,875,658 km (0.096 R)
• M22: 2,044,255 km (0.107 R)
• M23: 2,181,436 km (0.054 R)
• M24: 2,260,424 km (0.102 R)
• M25: 2,321,759 km (0.074 R)
• M26: 2,414,958 km (0.047 R)
• M27: 2,515,787 km (0.118 R)
• M28: 2,598,814 km (0.073 R)
• M29: 2,663,141 km (0.062 R)
• M30: 2,873,027 km (0.068 R)
• M31: 3,088,448 km (0.113 R)
• M32: 3,149,933 km (0.114 R)
• M33: 3,218,748 km (0.108 R)
• M34: 3,470,970 km (0.107 R)
• M35: 3,527,817 km (0.082 R)
• M36: 3,599,474 km (0.085 R)
• M37: 3,671,581 km (0.098 R)
• M38: 4,024,183 km (0.116 R)
• M39: 4,091,651 km (0.113 R)
• M40: 4,219,857 km (0.105 R)
• M41: 4,280,743 km (0.113 R)
• M42: 4,449,639 km (0.085 R)
• M43: 4,628,409 km (0.072 R)
• M44: 4,691,240 km (0.111 R)
• M45: 4,801,792 km (0.095 R)
• M46: 4,945,257 km (0.062 R)
• M47: 5,114,452 km (0.112 R)
• M48: 5,326,582 km (0.091 R)
• M49: 5,384,177 km (0.094 R)
• M50: 5,708,954 km (0.099 R)

Planet 3 - Gas Giant

Semi-Major Axis: 0.96 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 974.9

Radius: 10.2

Gravity: 9.37 G

Time & Orbit

Eccentricity (e): 0.134

Orbit Range: 0.83 AU - 1.09 AU

Year: 638 Days

Day: 9 Hours

Environment

Temp: -183 °C

Axial Tilt: 7.2 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (53)

Outer Limit: 33,098,770 km

• M1: 128,953 km (0.025 R)
• M2: 194,627 km (0.097 R)
• M3: 264,190 km (0.025 R)
• M4: 337,044 km (0.117 R)
• M5: 510,727 km (0.062 R)
• M6: 585,526 km (0.085 R)
• M7: 649,404 km (0.117 R)
• M8: 879,785 km (0.114 R)
• M9: 954,734 km (0.097 R)
• M10: 1,019,958 km (0.102 R)
• M11: 1,187,059 km (0.052 R)
• M12: 1,330,075 km (0.117 R)
• M13: 1,604,886 km (0.095 R)
• M14: 1,742,067 km (0.112 R)
• M15: 1,823,149 km (0.043 R)
• M16: 1,958,835 km (0.108 R)
• M17: 2,074,474 km (0.081 R)
• M18: 2,192,506 km (0.118 R)
• M19: 2,272,541 km (0.07 R)
• M20: 2,410,770 km (0.091 R)
• M21: 2,551,840 km (0.076 R)
• M22: 2,687,227 km (0.097 R)
• M23: 2,816,180 km (0.071 R)
• M24: 3,053,891 km (0.094 R)
• M25: 3,188,679 km (0.071 R)
• M26: 3,298,035 km (0.085 R)
• M27: 3,492,512 km (0.092 R)
• M28: 3,595,884 km (0.113 R)
• M29: 3,671,730 km (0.111 R)
• M30: 3,738,451 km (0.091 R)
• M31: 3,805,620 km (0.111 R)
• M32: 3,892,686 km (0.094 R)
• M33: 3,990,074 km (0.065 R)
• M34: 4,078,636 km (0.085 R)
• M35: 4,177,670 km (0.116 R)
• M36: 4,327,717 km (0.09 R)
• M37: 4,633,196 km (0.063 R)
• M38: 4,799,100 km (0.027 R)
• M39: 4,903,818 km (0.1 R)
• M40: 4,977,570 km (0.094 R)
• M41: 5,536,916 km (0.071 R)
• M42: 5,624,730 km (0.078 R)
• M43: 5,768,494 km (0.099 R)
• M44: 5,980,773 km (0.109 R)
• M45: 6,150,268 km (0.081 R)
• M46: 6,252,742 km (0.119 R)
• M47: 6,447,818 km (0.111 R)
• M48: 6,598,313 km (0.107 R)
• M49: 6,820,466 km (0.078 R)
• M50: 6,902,895 km (0.064 R)
• M51: 7,284,220 km (0.099 R)
• M52: 7,893,681 km (0.102 R)
• M53: 8,154,580 km (0.103 R)

Asteroid Belt

Center: 1.97 AU

Composition

Type: Outer System (Icy)

A dense region of planetesimals and debris.

Boundary

Planet 4 - Gas Giant

Semi-Major Axis: 2.98 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 20

Radius: 10.7

Gravity: 0.17 G

Time & Orbit

Eccentricity (e): 0.14

Orbit Range: 2.56 AU - 3.4 AU

Year: 3489 Days

Day: 10 Hours

Environment

Temp: -202 °C

Axial Tilt: 3 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (41)

Outer Limit: 33,098,770 km

• M1: 208,539 km (0.111 R)
• M2: 314,156 km (0.049 R)
• M3: 469,737 km (0.09 R)
• M4: 623,225 km (0.037 R)
• M5: 790,026 km (0.12 R)
• M6: 894,446 km (0.101 R)
• M7: 1,004,101 km (0.067 R)
• M8: 1,112,859 km (0.119 R)
• M9: 1,237,324 km (0.077 R)
• M10: 1,366,726 km (0.109 R)
• M11: 1,469,949 km (0.115 R)
• M12: 1,639,443 km (0.029 R)
• M13: 1,808,788 km (0.119 R)
• M14: 1,902,586 km (0.103 R)
• M15: 2,193,554 km (0.087 R)
• M16: 2,395,810 km (0.071 R)
• M17: 2,491,702 km (0.098 R)
• M18: 2,702,785 km (0.105 R)
• M19: 3,207,528 km (0.118 R)
• M20: 3,354,882 km (0.07 R)
• M21: 3,470,970 km (0.086 R)
• M22: 3,639,267 km (0.114 R)
• M23: 3,733,065 km (0.045 R)
• M24: 3,931,582 km (0.032 R)
• M25: 4,213,723 km (0.032 R)
• M26: 4,285,381 km (0.092 R)
• M27: 4,384,564 km (0.077 R)
• M28: 4,705,003 km (0.081 R)
• M29: 5,033,220 km (0.063 R)
• M30: 5,204,809 km (0.082 R)
• M31: 5,272,128 km (0.106 R)
• M32: 5,397,940 km (0.086 R)
• M33: 5,682,176 km (0.091 R)
• M34: 5,821,152 km (0.107 R)
• M35: 5,961,176 km (0.06 R)
• M36: 6,163,283 km (0.099 R)
• M37: 6,244,814 km (0.111 R)
• M38: 6,460,384 km (0.055 R)
• M39: 6,720,385 km (0.107 R)
• M40: 6,835,875 km (0.087 R)
• M41: 7,164,840 km (0.104 R)

Planet 5 - Gas Giant

Semi-Major Axis: 3.02 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 815.3

Radius: 9.4

Gravity: 9.23 G

Time & Orbit

Eccentricity (e): 0.171

Orbit Range: 2.5 AU - 3.54 AU

Year: 3560 Days

Day: 8.5 Hours

Environment

Temp: -208 °C

Axial Tilt: 28.3 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (78)

Outer Limit: 33,098,770 km

• M1: 138,528 km (0.083 R)
• M2: 199,713 km (0.094 R)
• M3: 276,158 km (0.084 R)
• M4: 335,548 km (0.108 R)
• M5: 400,773 km (0.095 R)
• M6: 547,528 km (0.036 R)
• M7: 659,577 km (0.053 R)
• M8: 768,634 km (0.036 R)
• M9: 896,091 km (0.088 R)
• M10: 981,063 km (0.079 R)
• M11: 1,348,774 km (0.112 R)
• M12: 1,607,130 km (0.087 R)
• M13: 1,696,739 km (0.119 R)
• M14: 1,803,702 km (0.043 R)
• M15: 1,897,051 km (0.091 R)
• M16: 2,560,966 km (0.093 R)
• M17: 3,291,452 km (0.084 R)
• M18: 3,522,880 km (0.101 R)
• M19: 3,620,717 km (0.102 R)
• M20: 3,879,821 km (0.094 R)
• M21: 3,960,753 km (0.107 R)
• M22: 4,083,124 km (0.082 R)
• M23: 4,269,224 km (0.086 R)
• M24: 4,458,017 km (0.072 R)
• M25: 4,521,596 km (0.04 R)
• M26: 4,953,335 km (0.081 R)
• M27: 5,972,396 km (0.071 R)
• M28: 6,231,200 km (0.036 R)
• M29: 6,638,555 km (0.063 R)
• M30: 6,735,644 km (0.117 R)
• M31: 7,054,437 km (0.087 R)
• M32: 7,328,052 km (0.089 R)
• M33: 7,783,428 km (0.083 R)
• M34: 7,885,902 km (0.097 R)
• M35: 8,300,288 km (0.12 R)
• M36: 8,457,366 km (0.096 R)
• M37: 8,562,833 km (0.095 R)
• M38: 9,204,009 km (0.048 R)
• M39: 9,916,244 km (0.089 R)
• M40: 10,027,396 km (0.074 R)
• M41: 10,222,920 km (0.098 R)
• M42: 10,674,556 km (0.09 R)
• M43: 11,017,584 km (0.081 R)
• M44: 11,161,497 km (0.119 R)
• M45: 11,451,418 km (0.081 R)
• M46: 11,568,104 km (0.115 R)
• M47: 11,802,524 km (0.115 R)
• M48: 12,395,680 km (0.04 R)
• M49: 12,665,704 km (0.11 R)
• M50: 12,968,041 km (0.086 R)
• M51: 13,334,107 km (0.032 R)
• M52: 13,951,647 km (0.032 R)
• M53: 14,201,326 km (0.057 R)
• M54: 15,375,071 km (0.095 R)
• M55: 15,794,842 km (0.034 R)
• M56: 16,480,898 km (0.055 R)
• M57: 16,744,938 km (0.095 R)
• M58: 16,943,754 km (0.097 R)
• M59: 17,545,137 km (0.114 R)
• M60: 17,645,966 km (0.058 R)
• M61: 19,356,020 km (0.101 R)
• M62: 19,844,158 km (0.11 R)
• M63: 20,019,486 km (0.1 R)
• M64: 20,195,413 km (0.083 R)
• M65: 20,619,673 km (0.063 R)
• M66: 20,726,037 km (0.095 R)
• M67: 21,620,782 km (0.038 R)
• M68: 21,765,144 km (0.04 R)
• M69: 22,018,413 km (0.096 R)
• M70: 22,127,320 km (0.116 R)
• M71: 22,821,006 km (0.118 R)
• M72: 23,189,016 km (0.093 R)
• M73: 23,299,719 km (0.071 R)
• M74: 23,596,072 km (0.067 R)
• M75: 23,930,872 km (0.081 R)
• M76: 24,117,421 km (0.073 R)
• M77: 25,058,092 km (0.081 R)
• M78: 25,247,633 km (0.083 R)

Planet 6 - Ice Giant

Semi-Major Axis: 7.89 AU

Status: Outer (Cold)

Composition: Methane/Ammonia Ices

Physical Data

Mass: 639.5

Radius: 6.1

Gravity: 17.19 G

Time & Orbit

Eccentricity (e): 0.115

Orbit Range: 6.98 AU - 8.8 AU

Year: 15032 Days

Day: 20.7 Hours

Environment

Temp: -233 °C

Axial Tilt: 159.7 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (95)

Outer Limit: 33,098,770 km

• M1: 146,756 km (0.088 R)
• M2: 188,643 km (0.118 R)
• M3: 443,857 km (0.105 R)
• M4: 530,624 km (0.118 R)
• M5: 846,275 km (0.11 R)
• M6: 955,781 km (0.069 R)
• M7: 1,069,924 km (0.115 R)
• M8: 1,212,940 km (0.044 R)
• M9: 1,873,713 km (0.098 R)
• M10: 2,017,477 km (0.049 R)
• M11: 2,501,576 km (0.079 R)
• M12: 2,564,556 km (0.043 R)
• M13: 3,020,381 km (0.101 R)
• M14: 3,571,649 km (0.109 R)
• M15: 3,895,379 km (0.061 R)
• M16: 4,153,585 km (0.084 R)
• M17: 4,341,480 km (0.099 R)
• M18: 6,454,699 km (0.108 R)
• M19: 6,541,466 km (0.079 R)
• M20: 7,159,754 km (0.115 R)
• M21: 7,339,870 km (0.117 R)
• M22: 7,567,109 km (0.077 R)
• M23: 8,309,713 km (0.076 R)
• M24: 8,689,692 km (0.084 R)
• M25: 8,978,415 km (0.113 R)
• M26: 9,075,355 km (0.041 R)
• M27: 9,664,322 km (0.081 R)
• M28: 10,265,555 km (0.076 R)
• M29: 10,775,834 km (0.118 R)
• M30: 11,138,010 km (0.095 R)
• M31: 11,451,567 km (0.095 R)
• M32: 11,821,074 km (0.03 R)
• M33: 12,301,882 km (0.087 R)
• M34: 12,734,519 km (0.036 R)
• M35: 13,670,702 km (0.053 R)
• M36: 13,726,502 km (0.105 R)
• M37: 13,894,201 km (0.103 R)
• M38: 14,514,883 km (0.09 R)
• M39: 14,914,609 km (0.03 R)
• M40: 15,841,966 km (0.117 R)
• M41: 16,135,477 km (0.105 R)
• M42: 16,253,509 km (0.085 R)
• M43: 16,907,252 km (0.076 R)
• M44: 16,967,091 km (0.076 R)
• M45: 17,087,069 km (0.11 R)
• M46: 18,548,191 km (0.039 R)
• M47: 19,044,108 km (0.07 R)
• M48: 19,859,117 km (0.09 R)
• M49: 21,135,187 km (0.061 R)
• M50: 21,199,813 km (0.059 R)
• M51: 21,393,692 km (0.104 R)
• M52: 21,458,468 km (0.111 R)
• M53: 22,635,205 km (0.06 R)
• M54: 23,364,794 km (0.105 R)
• M55: 24,236,800 km (0.091 R)
• M56: 25,119,427 km (0.054 R)
• M57: 25,256,160 km (0.075 R)
• M58: 26,985,960 km (0.082 R)
• M59: 27,971,211 km (0.106 R)
• M60: 29,255,360 km (0.108 R)
• M61: 29,759,953 km (0.04 R)
• M62: 29,832,209 km (0.104 R)
• M63: 30,777,518 km (0.065 R)
• M64: 30,850,671 km (0.117 R)
• M65: 31,364,241 km (0.042 R)
• M66: 31,954,554 km (0.074 R)
• M67: 32,697,607 km (0.102 R)
• M68: 33,898,279 km (0.111 R)
• M69: 34,125,069 km (0.116 R)
• M70: 34,428,155 km (0.066 R)
• M71: 35,572,728 km (0.117 R)
• M72: 36,574,884 km (0.086 R)
• M73: 37,040,433 km (0.067 R)
• M74: 40,514,395 km (0.039 R)
• M75: 40,915,766 km (0.034 R)
• M76: 41,076,583 km (0.098 R)
• M77: 42,615,497 km (0.103 R)
• M78: 43,269,090 km (0.095 R)
• M79: 43,433,049 km (0.106 R)
• M80: 44,090,831 km (0.104 R)
• M81: 45,166,739 km (0.063 R)
• M82: 45,582,770 km (0.071 R)
• M83: 45,916,523 km (0.118 R)
• M84: 46,418,723 km (0.102 R)
• M85: 46,502,648 km (0.03 R)
• M86: 47,513,181 km (0.044 R)
• M87: 49,470,071 km (0.06 R)
• M88: 49,727,230 km (0.105 R)
• M89: 52,148,920 km (0.093 R)
• M90: 53,902,207 km (0.093 R)
• M91: 53,990,320 km (0.106 R)
• M92: 54,963,454 km (0.091 R)
• M93: 57,286,111 km (0.095 R)
• M94: 58,278,543 km (0.111 R)
• M95: 58,731,376 km (0.084 R)

Planet 7 - Ice Giant

Semi-Major Axis: 9.15 AU

Status: Outer (Cold)

Composition: Methane/Ammonia Ices

Physical Data

Mass: 64

Radius: 3.7

Gravity: 4.67 G

Time & Orbit

Eccentricity (e): 0.205

Orbit Range: 7.27 AU - 11.03 AU

Year: 18773 Days

Day: 18.8 Hours

Environment

Temp: -233 °C

Axial Tilt: 23.4 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (68)

Outer Limit: 33,098,770 km

• M1: 300,542 km (0.049 R)
• M2: 382,821 km (0.119 R)
• M3: 711,338 km (0.084 R)
• M4: 923,617 km (0.025 R)
• M5: 1,595,312 km (0.042 R)
• M6: 1,667,268 km (0.077 R)
• M7: 1,777,372 km (0.078 R)
• M8: 1,852,171 km (0.059 R)
• M9: 2,082,552 km (0.034 R)
• M10: 2,161,390 km (0.059 R)
• M11: 2,322,058 km (0.075 R)
• M12: 2,403,739 km (0.089 R)
• M13: 2,528,204 km (0.093 R)
• M14: 2,654,764 km (0.109 R)
• M15: 3,069,150 km (0.104 R)
• M16: 3,410,233 km (0.108 R)
• M17: 3,433,421 km (0.047 R)
• M18: 3,980,949 km (0.092 R)
• M19: 4,103,470 km (0.113 R)
• M20: 4,504,093 km (0.046 R)
• M21: 4,606,118 km (0.032 R)
• M22: 4,734,773 km (0.059 R)
• M23: 5,341,990 km (0.056 R)
• M24: 5,504,304 km (0.072 R)
• M25: 6,085,342 km (0.048 R)
• M26: 6,198,289 km (0.068 R)
• M27: 6,831,387 km (0.089 R)
• M28: 7,454,761 km (0.079 R)
• M29: 7,911,184 km (0.055 R)
• M30: 8,220,403 km (0.094 R)
• M31: 8,596,642 km (0.053 R)
• M32: 9,990,445 km (0.105 R)
• M33: 10,764,165 km (0.054 R)
• M34: 11,522,178 km (0.112 R)
• M35: 11,978,152 km (0.107 R)
• M36: 12,547,521 km (0.025 R)
• M37: 13,491,185 km (0.073 R)
• M38: 13,601,588 km (0.087 R)
• M39: 14,307,391 km (0.04 R)
• M40: 15,484,427 km (0.113 R)
• M41: 16,929,393 km (0.087 R)
• M42: 17,127,909 km (0.114 R)
• M43: 17,688,003 km (0.089 R)
• M44: 17,970,295 km (0.047 R)
• M45: 18,213,391 km (0.066 R)
• M46: 19,320,864 km (0.114 R)
• M47: 19,362,303 km (0.037 R)
• M48: 19,569,945 km (0.072 R)
• M49: 19,736,597 km (0.064 R)
• M50: 20,029,360 km (0.081 R)
• M51: 21,086,418 km (0.088 R)
• M52: 21,257,259 km (0.113 R)
• M53: 21,428,549 km (0.046 R)
• M54: 21,729,390 km (0.027 R)
• M55: 23,608,040 km (0.103 R)
• M56: 23,829,744 km (0.1 R)
• M57: 25,401,569 km (0.081 R)
• M58: 25,856,795 km (0.115 R)
• M59: 27,331,531 km (0.118 R)
• M60: 27,891,476 km (0.11 R)
• M61: 28,644,103 km (0.045 R)
• M62: 28,833,194 km (0.083 R)
• M63: 29,737,514 km (0.044 R)
• M64: 29,929,148 km (0.103 R)
• M65: 30,265,295 km (0.11 R)
• M66: 30,506,147 km (0.11 R)
• M67: 30,796,218 km (0.11 R)
• M68: 31,281,364 km (0.105 R)

Kuiper Belt

Range: 30 - 54 AU

Composition

Type: Dwarf Planets/TNOs (Ices)

Reservoir of dwarf planets and volatile ices.

Outer System

Oort Cloud

Range: 280 - 10,657 AU

Composition

Type: Cometary Reservoir

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

Gravitational Limit