🌌 Stone's Star System Generator

Asteroid Belt

Center: 0.29 AU

Composition

Type: Inner (Rocky/Metallic)

A dense region of planetesimals and debris.

Boundary

Planet 1 - Terrestrial

Semi-Major Axis: 0.57 AU

Status: Outer (Cold)

Composition: Rocky (Silicates/Metals)

Physical Data

Mass: 0.32

Radius: 0.63

Gravity: 0.81 G

Time & Orbit

Eccentricity (e): 0.104

Orbit Range: 0.51 AU - 0.63 AU

Year: 282 Days

Day: 23.5 Hours

Environment

Temp: -119 °C

Axial Tilt: 41.7 °

Atmosphere: Thin N₂/CH₄

Biome: Ice Cap/Desert

Planet 2 - Gas Giant

Semi-Major Axis: 1.01 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 978

Radius: 10.9

Gravity: 8.23 G

Time & Orbit

Eccentricity (e): 0.044

Orbit Range: 0.97 AU - 1.05 AU

Year: 666 Days

Day: 11.4 Hours

Environment

Temp: -163 °C

Axial Tilt: 2.1 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (58)

Outer Limit: 50,292,266 km

• M1: 147,055 km (0.111 R)
• M2: 218,862 km (0.093 R)
• M3: 293,810 km (0.112 R)
• M4: 403,465 km (0.048 R)
• M5: 476,020 km (0.077 R)
• M6: 622,626 km (0.1 R)
• M7: 763,847 km (0.093 R)
• M8: 928,255 km (0.101 R)
• M9: 1,042,697 km (0.096 R)
• M10: 1,111,213 km (0.113 R)
• M11: 1,233,584 km (0.101 R)
• M12: 1,326,634 km (0.118 R)
• M13: 1,408,464 km (0.118 R)
• M14: 1,499,120 km (0.075 R)
• M15: 1,584,690 km (0.032 R)
• M16: 1,775,727 km (0.079 R)
• M17: 2,005,808 km (0.088 R)
• M18: 2,205,073 km (0.088 R)
• M19: 2,286,753 km (0.094 R)
• M20: 2,427,824 km (0.058 R)
• M21: 2,503,670 km (0.067 R)
• M22: 2,588,941 km (0.049 R)
• M23: 2,957,999 km (0.073 R)
• M24: 3,231,912 km (0.069 R)
• M25: 3,523,628 km (0.104 R)
• M26: 3,765,229 km (0.076 R)
• M27: 4,042,284 km (0.104 R)
• M28: 4,183,355 km (0.073 R)
• M29: 4,326,221 km (0.084 R)
• M30: 4,398,177 km (0.119 R)
• M31: 4,512,021 km (0.104 R)
• M32: 4,690,192 km (0.073 R)
• M33: 4,849,215 km (0.12 R)
• M34: 4,924,014 km (0.084 R)
• M35: 5,031,724 km (0.105 R)
• M36: 5,205,408 km (0.1 R)
• M37: 5,348,124 km (0.102 R)
• M38: 5,525,547 km (0.077 R)
• M39: 5,660,035 km (0.08 R)
• M40: 5,897,746 km (0.087 R)
• M41: 6,092,672 km (0.118 R)
• M42: 6,196,793 km (0.056 R)
• M43: 6,465,470 km (0.102 R)
• M44: 6,678,348 km (0.102 R)
• M45: 6,821,663 km (0.105 R)
• M46: 6,929,822 km (0.034 R)
• M47: 7,111,284 km (0.097 R)
• M48: 7,306,659 km (0.108 R)
• M49: 7,404,945 km (0.078 R)
• M50: 7,540,929 km (0.085 R)
• M51: 7,727,628 km (0.086 R)
• M52: 7,915,971 km (0.066 R)
• M53: 8,169,390 km (0.076 R)
• M54: 8,258,700 km (0.109 R)
• M55: 8,348,459 km (0.103 R)
• M56: 8,438,367 km (0.098 R)
• M57: 8,554,605 km (0.094 R)
• M58: 8,840,785 km (0.102 R)

Planet 3 - Gas Giant

Semi-Major Axis: 1.93 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 252

Radius: 11.6

Gravity: 1.87 G

Time & Orbit

Eccentricity (e): 0.102

Orbit Range: 1.73 AU - 2.13 AU

Year: 1759 Days

Day: 6.4 Hours

Environment

Temp: -195 °C

Axial Tilt: 2.8 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (54)

Outer Limit: 50,292,266 km

• M1: 150,495 km (0.105 R)
• M2: 349,760 km (0.104 R)
• M3: 436,227 km (0.106 R)
• M4: 527,033 km (0.113 R)
• M5: 707,448 km (0.032 R)
• M6: 831,465 km (0.06 R)
• M7: 977,024 km (0.118 R)
• M8: 1,146,069 km (0.071 R)
• M9: 1,219,522 km (0.106 R)
• M10: 1,294,770 km (0.052 R)
• M11: 1,371,663 km (0.071 R)
• M12: 1,466,059 km (0.083 R)
• M13: 1,644,978 km (0.104 R)
• M14: 1,989,203 km (0.025 R)
• M15: 2,160,941 km (0.071 R)
• M16: 2,234,693 km (0.063 R)
• M17: 2,805,259 km (0.028 R)
• M18: 2,957,400 km (0.118 R)
• M19: 3,185,687 km (0.061 R)
• M20: 3,344,709 km (0.051 R)
• M21: 3,517,345 km (0.113 R)
• M22: 3,715,114 km (0.112 R)
• M23: 3,871,443 km (0.038 R)
• M24: 4,007,278 km (0.067 R)
• M25: 4,098,682 km (0.025 R)
• M26: 4,295,404 km (0.087 R)
• M27: 4,447,844 km (0.114 R)
• M28: 4,602,229 km (0.116 R)
• M29: 4,770,377 km (0.105 R)
• M30: 4,891,850 km (0.083 R)
• M31: 5,051,172 km (0.117 R)
• M32: 5,350,069 km (0.08 R)
• M33: 5,501,611 km (0.113 R)
• M34: 5,848,080 km (0.067 R)
• M35: 6,004,410 km (0.069 R)
• M36: 6,148,772 km (0.108 R)
• M37: 6,321,108 km (0.099 R)
• M38: 6,508,405 km (0.111 R)
• M39: 6,779,177 km (0.12 R)
• M40: 6,888,533 km (0.095 R)
• M41: 6,984,725 km (0.091 R)
• M42: 7,164,541 km (0.064 R)
• M43: 7,486,476 km (0.083 R)
• M44: 7,770,263 km (0.08 R)
• M45: 7,927,939 km (0.089 R)
• M46: 8,014,407 km (0.091 R)
• M47: 8,173,579 km (0.111 R)
• M48: 8,363,269 km (0.111 R)
• M49: 8,569,116 km (0.056 R)
• M50: 8,791,568 km (0.086 R)
• M51: 8,910,947 km (0.079 R)
• M52: 9,424,516 km (0.118 R)
• M53: 9,715,634 km (0.085 R)
• M54: 10,480,228 km (0.038 R)

Planet 4 - Gas Giant

Semi-Major Axis: 2.23 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 115.9

Radius: 11

Gravity: 0.96 G

Time & Orbit

Eccentricity (e): 0.228

Orbit Range: 1.72 AU - 2.74 AU

Year: 2185 Days

Day: 13.3 Hours

Environment

Temp: -203 °C

Axial Tilt: 39.7 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (47)

Outer Limit: 50,292,266 km

• M1: 167,699 km (0.033 R)
• M2: 236,514 km (0.045 R)
• M3: 410,048 km (0.065 R)
• M4: 617,540 km (0.026 R)
• M5: 772,075 km (0.043 R)
• M6: 1,010,234 km (0.066 R)
• M7: 1,216,679 km (0.099 R)
• M8: 1,386,323 km (0.113 R)
• M9: 1,780,963 km (0.045 R)
• M10: 1,877,004 km (0.071 R)
• M11: 2,167,374 km (0.104 R)
• M12: 2,331,184 km (0.069 R)
• M13: 2,427,824 km (0.102 R)
• M14: 2,543,912 km (0.081 R)
• M15: 2,634,568 km (0.113 R)
• M16: 2,726,272 km (0.088 R)
• M17: 2,847,147 km (0.098 R)
• M18: 3,289,208 km (0.08 R)
• M19: 3,408,139 km (0.114 R)
• M20: 3,558,933 km (0.109 R)
• M21: 3,670,982 km (0.05 R)
• M22: 4,045,725 km (0.102 R)
• M23: 4,323,977 km (0.12 R)
• M24: 4,454,725 km (0.084 R)
• M25: 4,686,452 km (0.118 R)
• M26: 4,809,422 km (0.103 R)
• M27: 5,464,062 km (0.082 R)
• M28: 5,641,037 km (0.073 R)
• M29: 5,760,116 km (0.036 R)
• M30: 5,976,585 km (0.118 R)
• M31: 6,146,677 km (0.084 R)
• M32: 6,380,349 km (0.097 R)
• M33: 6,729,959 km (0.077 R)
• M34: 6,843,654 km (0.106 R)
• M35: 7,072,987 km (0.064 R)
• M36: 7,253,103 km (0.096 R)
• M37: 7,330,744 km (0.048 R)
• M38: 8,015,753 km (0.061 R)
• M39: 8,122,865 km (0.066 R)
• M40: 8,271,117 km (0.113 R)
• M41: 8,393,039 km (0.09 R)
• M42: 8,474,570 km (0.057 R)
• M43: 8,597,539 km (0.106 R)
• M44: 8,666,055 km (0.094 R)
• M45: 8,817,448 km (0.058 R)
• M46: 8,955,976 km (0.095 R)
• M47: 9,053,214 km (0.107 R)

Planet 5 - Gas Giant

Semi-Major Axis: 3.57 AU

Status: Outer (Cold)

Composition: Hydrogen/Helium Atmosphere

Physical Data

Mass: 678.1

Radius: 11

Gravity: 5.6 G

Time & Orbit

Eccentricity (e): 0.034

Orbit Range: 3.45 AU - 3.69 AU

Year: 4425 Days

Day: 5 Hours

Environment

Temp: -209 °C

Axial Tilt: 37.1 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (78)

Outer Limit: 50,292,266 km

• M1: 160,369 km (0.101 R)
• M2: 239,357 km (0.038 R)
• M3: 357,689 km (0.059 R)
• M4: 594,203 km (0.082 R)
• M5: 715,078 km (0.117 R)
• M6: 907,012 km (0.097 R)
• M7: 1,035,965 km (0.082 R)
• M8: 1,475,633 km (0.105 R)
• M9: 1,598,304 km (0.113 R)
• M10: 1,708,408 km (0.118 R)
• M11: 2,386,834 km (0.086 R)
• M12: 2,642,796 km (0.078 R)
• M13: 2,965,778 km (0.054 R)
• M14: 3,484,284 km (0.09 R)
• M15: 3,712,122 km (0.101 R)
• M16: 3,859,775 km (0.034 R)
• M17: 4,009,373 km (0.12 R)
• M18: 4,358,684 km (0.049 R)
• M19: 4,447,545 km (0.068 R)
• M20: 4,582,033 km (0.096 R)
• M21: 4,763,495 km (0.098 R)
• M22: 4,901,125 km (0.072 R)
• M23: 5,063,439 km (0.092 R)
• M24: 5,464,960 km (0.058 R)
• M25: 5,730,346 km (0.109 R)
• M26: 5,876,952 km (0.062 R)
• M27: 6,475,643 km (0.117 R)
• M28: 6,628,382 km (0.055 R)
• M29: 6,782,319 km (0.043 R)
• M30: 6,859,661 km (0.111 R)
• M31: 7,172,470 km (0.074 R)
• M32: 7,251,308 km (0.111 R)
• M33: 7,436,510 km (0.074 R)
• M34: 7,569,802 km (0.112 R)
• M35: 7,677,064 km (0.113 R)
• M36: 8,110,897 km (0.092 R)
• M37: 8,330,956 km (0.059 R)
• M38: 8,497,159 km (0.045 R)
• M39: 9,201,915 km (0.087 R)
• M40: 9,691,848 km (0.113 R)
• M41: 10,042,804 km (0.07 R)
• M42: 10,547,248 km (0.113 R)
• M43: 10,757,284 km (0.108 R)
• M44: 11,212,211 km (0.103 R)
• M45: 11,984,435 km (0.105 R)
• M46: 12,109,499 km (0.105 R)
• M47: 12,266,577 km (0.058 R)
• M48: 12,550,962 km (0.084 R)
• M49: 12,773,713 km (0.108 R)
• M50: 12,869,606 km (0.087 R)
• M51: 13,612,509 km (0.079 R)
• M52: 14,071,475 km (0.087 R)
• M53: 14,468,956 km (0.086 R)
• M54: 14,870,178 km (0.073 R)
• M55: 14,971,007 km (0.119 R)
• M56: 15,207,222 km (0.12 R)
• M57: 15,308,949 km (0.107 R)
• M58: 15,478,742 km (0.056 R)
• M59: 15,615,175 km (0.106 R)
• M60: 15,717,650 km (0.085 R)
• M61: 15,923,497 km (0.088 R)
• M62: 16,026,719 km (0.103 R)
• M63: 16,546,123 km (0.084 R)
• M64: 17,637,140 km (0.101 R)
• M65: 18,570,032 km (0.117 R)
• M66: 18,751,345 km (0.03 R)
• M67: 20,371,490 km (0.118 R)
• M68: 21,009,525 km (0.109 R)
• M69: 21,122,771 km (0.101 R)
• M70: 21,501,852 km (0.075 R)
• M71: 23,001,421 km (0.055 R)
• M72: 23,274,138 km (0.088 R)
• M73: 24,256,996 km (0.113 R)
• M74: 24,813,350 km (0.066 R)
• M75: 25,293,559 km (0.091 R)
• M76: 25,655,736 km (0.094 R)
• M77: 25,817,152 km (0.116 R)
• M78: 27,285,904 km (0.111 R)

Planet 6 - Ice Giant

Semi-Major Axis: 7.77 AU

Status: Outer (Cold)

Composition: Methane/Ammonia Ices

Physical Data

Mass: 650.2

Radius: 7.2

Gravity: 12.54 G

Time & Orbit

Eccentricity (e): 0.228

Orbit Range: 6 AU - 9.54 AU

Year: 14208 Days

Day: 21.5 Hours

Environment

Temp: -227 °C

Axial Tilt: 14.9 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (89)

Outer Limit: 50,292,266 km

• M1: 167,699 km (0.081 R)
• M2: 257,608 km (0.113 R)
• M3: 310,565 km (0.113 R)
• M4: 398,379 km (0.109 R)
• M5: 478,863 km (0.086 R)
• M6: 582,983 km (0.045 R)
• M7: 714,629 km (0.057 R)
• M8: 963,261 km (0.095 R)
• M9: 1,051,972 km (0.083 R)
• M10: 1,588,729 km (0.089 R)
• M11: 1,694,645 km (0.104 R)
• M12: 1,775,577 km (0.104 R)
• M13: 2,170,216 km (0.113 R)
• M14: 3,647,196 km (0.093 R)
• M15: 3,894,182 km (0.045 R)
• M16: 4,935,383 km (0.038 R)
• M17: 5,208,399 km (0.059 R)
• M18: 5,728,850 km (0.085 R)
• M19: 6,140,245 km (0.089 R)
• M20: 6,904,989 km (0.118 R)
• M21: 8,476,066 km (0.103 R)
• M22: 8,522,441 km (0.09 R)
• M23: 9,421,375 km (0.095 R)
• M24: 10,004,507 km (0.095 R)
• M25: 10,102,793 km (0.091 R)
• M26: 11,307,654 km (0.114 R)
• M27: 11,823,019 km (0.108 R)
• M28: 12,293,355 km (0.03 R)
• M29: 12,983,450 km (0.081 R)
• M30: 14,014,777 km (0.113 R)
• M31: 14,735,390 km (0.054 R)
• M32: 15,867,547 km (0.093 R)
• M33: 16,270,264 km (0.106 R)
• M34: 16,328,159 km (0.111 R)
• M35: 16,910,095 km (0.066 R)
• M36: 17,027,379 km (0.035 R)
• M37: 17,498,912 km (0.049 R)
• M38: 17,558,152 km (0.097 R)
• M39: 18,034,622 km (0.103 R)
• M40: 18,636,005 km (0.09 R)
• M41: 19,489,162 km (0.101 R)
• M42: 19,550,647 km (0.083 R)
• M43: 19,920,452 km (0.053 R)
• M44: 19,982,386 km (0.099 R)
• M45: 20,417,267 km (0.119 R)
• M46: 20,792,608 km (0.056 R)
• M47: 21,044,082 km (0.055 R)
• M48: 21,486,443 km (0.102 R)
• M49: 22,188,057 km (0.093 R)
• M50: 23,091,628 km (0.105 R)
• M51: 25,739,062 km (0.079 R)
• M52: 25,873,999 km (0.116 R)
• M53: 26,144,472 km (0.107 R)
• M54: 26,347,925 km (0.108 R)
• M55: 29,180,860 km (0.028 R)
• M56: 29,251,171 km (0.088 R)
• M57: 30,955,091 km (0.099 R)
• M58: 31,963,979 km (0.059 R)
• M59: 32,108,939 km (0.1 R)
• M60: 32,910,335 km (0.113 R)
• M61: 33,865,816 km (0.104 R)
• M62: 34,607,074 km (0.097 R)
• M63: 35,129,170 km (0.111 R)
• M64: 35,578,712 km (0.082 R)
• M65: 35,804,156 km (0.117 R)
• M66: 37,014,702 km (0.089 R)
• M67: 37,090,847 km (0.112 R)
• M68: 37,548,617 km (0.103 R)
• M69: 38,623,926 km (0.049 R)
• M70: 41,593,294 km (0.087 R)
• M71: 42,227,739 km (0.102 R)
• M72: 42,705,704 km (0.111 R)
• M73: 43,827,838 km (0.078 R)
• M74: 44,150,221 km (0.082 R)
• M75: 45,122,159 km (0.111 R)
• M76: 46,101,127 km (0.118 R)
• M77: 46,346,916 km (0.106 R)
• M78: 47,334,711 km (0.065 R)
• M79: 50,339,085 km (0.074 R)
• M80: 50,761,250 km (0.071 R)
• M81: 54,007,674 km (0.089 R)
• M82: 54,180,459 km (0.114 R)
• M83: 54,960,014 km (0.097 R)
• M84: 56,355,014 km (0.092 R)
• M85: 56,881,000 km (0.07 R)
• M86: 57,408,781 km (0.089 R)
• M87: 57,673,270 km (0.111 R)
• M88: 58,824,127 km (0.064 R)
• M89: 59,268,732 km (0.099 R)

Planet 7 - Ice Giant

Semi-Major Axis: 9.27 AU

Status: Outer (Cold)

Composition: Methane/Ammonia Ices

Physical Data

Mass: 230.8

Radius: 5.5

Gravity: 7.63 G

Time & Orbit

Eccentricity (e): 0.025

Orbit Range: 9.04 AU - 9.5 AU

Year: 18515 Days

Day: 23.4 Hours

Environment

Temp: -226 °C

Axial Tilt: 37.3 °

Atmosphere: H₂, CH₄

Biome: None

Satellites (96)

Outer Limit: 50,292,266 km

• M1: 189,690 km (0.111 R)
• M2: 291,267 km (0.115 R)
• M3: 596,596 km (0.069 R)
• M4: 681,269 km (0.085 R)
• M5: 733,927 km (0.069 R)
• M6: 1,099,993 km (0.06 R)
• M7: 1,141,581 km (0.076 R)
• M8: 1,680,433 km (0.097 R)
• M9: 2,130,124 km (0.03 R)
• M10: 2,449,665 km (0.115 R)
• M11: 2,559,620 km (0.113 R)
• M12: 2,870,185 km (0.109 R)
• M13: 3,133,178 km (0.051 R)
• M14: 3,373,582 km (0.109 R)
• M15: 4,162,411 km (0.092 R)
• M16: 4,764,243 km (0.054 R)
• M17: 5,075,257 km (0.096 R)
• M18: 5,393,003 km (0.114 R)
• M19: 5,608,275 km (0.11 R)
• M20: 7,589,549 km (0.099 R)
• M21: 8,197,515 km (0.062 R)
• M22: 8,238,654 km (0.081 R)
• M23: 8,445,099 km (0.074 R)
• M24: 9,546,139 km (0.091 R)
• M25: 9,850,272 km (0.046 R)
• M26: 10,025,451 km (0.085 R)
• M27: 10,201,677 km (0.116 R)
• M28: 10,961,934 km (0.07 R)
• M29: 11,417,758 km (0.101 R)
• M30: 11,972,766 km (0.045 R)
• M31: 12,206,737 km (0.099 R)
• M32: 12,774,162 km (0.078 R)
• M33: 12,965,199 km (0.074 R)
• M34: 13,398,584 km (0.097 R)
• M35: 13,447,053 km (0.11 R)
• M36: 13,495,523 km (0.034 R)
• M37: 13,738,919 km (0.055 R)
• M38: 14,180,681 km (0.115 R)
• M39: 15,128,533 km (0.113 R)
• M40: 15,178,948 km (0.081 R)
• M41: 15,584,508 km (0.058 R)
• M42: 16,199,654 km (0.09 R)
• M43: 16,822,729 km (0.086 R)
• M44: 17,612,606 km (0.095 R)
• M45: 18,092,217 km (0.093 R)
• M46: 18,630,171 km (0.039 R)
• M47: 18,955,546 km (0.033 R)
• M48: 19,556,930 km (0.097 R)
• M49: 20,275,598 km (0.12 R)
• M50: 20,331,248 km (0.116 R)
• M51: 20,834,196 km (0.039 R)
• M52: 21,115,440 km (0.109 R)
• M53: 21,171,839 km (0.118 R)
• M54: 21,454,728 km (0.096 R)
• M55: 21,568,123 km (0.096 R)
• M56: 22,138,390 km (0.091 R)
• M57: 23,235,541 km (0.092 R)
• M58: 23,410,272 km (0.056 R)
• M59: 24,468,527 km (0.06 R)
• M60: 25,662,617 km (0.088 R)
• M61: 26,814,371 km (0.085 R)
• M62: 27,488,908 km (0.116 R)
• M63: 27,920,947 km (0.111 R)
• M64: 30,051,669 km (0.117 R)
• M65: 30,178,678 km (0.094 R)
• M66: 30,433,144 km (0.118 R)
• M67: 30,624,479 km (0.073 R)
• M68: 31,200,730 km (0.068 R)
• M69: 32,039,526 km (0.109 R)
• M70: 32,234,152 km (0.115 R)
• M71: 33,344,318 km (0.115 R)
• M72: 33,607,461 km (0.091 R)
• M73: 33,739,257 km (0.114 R)
• M74: 33,805,080 km (0.053 R)
• M75: 34,799,606 km (0.079 R)
• M76: 34,866,327 km (0.111 R)
• M77: 34,932,898 km (0.063 R)
• M78: 35,066,489 km (0.096 R)
• M79: 35,938,345 km (0.083 R)
• M80: 36,478,394 km (0.113 R)
• M81: 39,426,968 km (0.062 R)
• M82: 40,053,633 km (0.094 R)
• M83: 41,953,676 km (0.119 R)
• M84: 42,166,553 km (0.105 R)
• M85: 42,593,506 km (0.104 R)
• M86: 43,164,820 km (0.084 R)
• M87: 43,308,135 km (0.03 R)
• M88: 43,738,827 km (0.11 R)
• M89: 44,026,803 km (0.106 R)
• M90: 45,039,581 km (0.113 R)
• M91: 46,206,294 km (0.078 R)
• M92: 46,719,864 km (0.109 R)
• M93: 47,161,626 km (0.103 R)
• M94: 47,456,933 km (0.07 R)
• M95: 47,604,735 km (0.069 R)
• M96: 47,826,738 km (0.081 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: 251 - 12,079 AU

Composition

Type: Cometary Reservoir

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

Gravitational Limit