Perihelion: 2,748,938,461 km, 18.37551863 AE
Aphelion: 3,004,419,704 km, 20.08330526 AE
Semi-major axis: 2,876,679,082 km, 19.22941195 AE
Orbital period: 30,799.095 days, 84.323326 years
Synodic period: 369.66 days
Average orbital speed: 6.81 km/s
Mean anomaly: 142.955717°
Inclination: 0.772 556°
Longitude of ascending node: 73.989821°
Argument of perihelion: 96.541 318°
Satellites/moons: 27 (Cordelia, Ophelia, Bianca, Cressida, Desdemona, Juliet, Portia, Rosalind, Mab, Belinda, Perdita, Puck, Cupid, Miranda, Francisco, Ariel, Umbriel, Titania, Oberon, Caliban, Stephano, Trinculo, Sycorax, Margaret, Prospero, Setebos, Ferdinand)
Equatorial radius: 25,559 km (4.007 x Earth)
Flattening: 0.0229 ± 0.0008
Surface area: 8.1156×109 km2 (15.91 x Earth)
Volume: 6.833×1013 km3 (63.086 x Earth)
Mass: 8.6823×1025 kg (14.536 x Earth)
Mean density: 1.27 g/cm3
Equatorial surface gravity: 8.69 m/s2
Escape velocity: 21.3 km/s
Sidereal rotation period: −0.71833 day Earth days, 17 h 14 min 24 s Earth hours
Average surface temperatures: 57 K, -216 °C, -357 °F
Apparent magnitude: 5.9 to 5.32
Angular diameter: 3.3"–4.1"
Composition: 82.5% Hydrogen (H2)
2.3% Methane (CH4)
148ppm Hydrogen Deuteride (HD)
back to main page
NASA Breaking News
NASA to Host Media Briefing on Mission to Return Asteroid Sample to Earth
NASA will host a media teleconference at 2 p.m. EDT Friday, Aug. 24, to provide an update on upcoming activities related to the agency’s first mission to return a sample of an asteroid to Earth.
NASA Hosts Live Science Chat: One Year After Eclipse 2017
On the one-year anniversary of the historic 2017 Eclipse Across America, NASA will host a Science Chat at 10:30 a.m. EDT, Tuesday, Aug. 21, to discuss new science data and the public impact of the celestial event experienced by millions.
NASA to Host Media Briefing on New Ice-Monitoring Mission
NASA will host a media teleconference at 1 p.m. EDT Wednesday, Aug. 22, to discuss the upcoming launch of the Ice, Cloud and land Elevation Satellite (ICESat-2), which will fly NASA’s most advanced laser altimeter to measure Earth’s changing ice.
NASA Awards Contract for Construction of New Research Support Building
NASA has selected Walsh Construction Company II, LLC of Chicago to build a new Research Support Building (RSB) at the agency’s Glenn Research Center in Cleveland.
NASA, ULA Launch Parker Solar Probe on Historic Journey to Touch Sun
Hours before the rise of the very star it will study, NASA’s Parker Solar Probe launched from Florida Sunday to begin its journey to the Sun, where it will undertake a landmark mission. The spacecraft will transmit its first science observations in December, beginning a revolution in our understanding of the star that makes life on Earth possible.
NASA Awards $2.3 Million in Grants to Minority Serving Institutions to Expand STEM Education
NASA's Minority University Research and Education Program (MUREP) Aerospace Academy (MAA) has selected seven Minority Serving Institutions (MSIs) for cooperative agreement awards totaling nearly $2.3 million.
NASA Astronaut to Speak with Students, Parents, Teachers at YouthSpark
Students attending Microsoft’s YouthSpark event will have the opportunity to speak with NASA astronauts aboard the International Space Station next week as part of NASA’s Year of Education on Station.
NASA Television to Air Russian Spacewalk at International Space Station
Russian cosmonauts living and working on the International Space Station will venture outside Wednesday, Aug. 15, for a spacewalk expected to last about six hours. Live coverage of the excursion will air on NASA Television and the agency’s website.
NASA Invests in Concepts for a Vibrant Future Commercial Space Economy
In an ongoing effort to foster commercial activity in space, NASA has selected 13 companies to study the future of commercial human spaceflight in low-Earth orbit, including long-range opportunities for the International Space Station.
NASA Announces New Partnerships to Develop Space Exploration Technologies
NASA is partnering with six U.S. companies to develop 10 “tipping point” technologies that have the potential to significantly benefit the commercial space economy and future NASA missions, including lunar lander and deep space rocket engine technologies.