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- In Depth | 1P Halley – NASA Solar System Exploration
Comet Halley moves backward (opposite to Earth's motion) around the Sun in a plane tilted 18 degrees to that of the Earth's orbit Halley's backward, or retrograde, motion is unusual among short-period comets, as its greatest distance from the Sun (aphelion) is beyond the orbit of Neptune
- Asteroids, Comets Meteors - NASA Solar System Exploration
Asteroids and comets – and the meteors that sometimes come from them – are leftovers from the formation of our solar system 4 6 billion years ago
- C 1995 O1 (Hale-Bopp) - NASA Solar System Exploration
Comet Hale-Bopp (C 1995 O1) was discovered on 23 July 1995 by two independent observers, Alan Hale (Cloudcroft, N M ) and Thomas Bopp (Stanfield, AZ), and is showing potential of putting on a spectacular display as it nears its 1997 perihelion The image above was taken by the Hubble Space Telescope, and shows material ejected from the rotating comet in a "pinwheel" pattern
- In Depth | 2P Encke – NASA Solar System Exploration
Discovery Comet 2P Encke was first discovered by Pierre F A Mechain on Jan 17, 1786 Other astronomers located this comet in subsequent passages, but these sightings were not defined as the same comet until Johann Franz Encke calculated its orbit Overview Comet 2P Encke is a small comet Its nucleus measures approximately 2 98 miles (4 8 kilometers) in diameter, which is about a third of
- In Depth | 21P Giacobini-Zinner – NASA Solar System Exploration
Discovery Comet Giacobini-Zinner was discovered on Dec 20, 1900 by Michel Giacobini at the Nice Observatory in France The comet was later recovered by Ernst Zinner in 1913 (October 23) Overview Comet 21P Giacobini-Zinner is a small comet with a diameter of 1 24 miles (2 kilometers) This comet takes about 6 6 years to orbit the Sun once The last time comet Giacobini-Zinner reached
- In Depth | Oumuamua – NASA Solar System Exploration
Discovery The first known interstellar object to visit our solar system, 1I 2017 U1 ‘Oumuamua, was discovered Oct 19, 2017 by the University of Hawaii’s Pan-STARRS1 telescope, funded by NASA’s Near-Earth Object Observations (NEOO) Program, which finds and tracks asteroids and comets in Earth’s neighborhood While originally classified as a comet, observations revealed no signs of
- Kuiper Belt and Oort Cloud - NASA Solar System Exploration
The Oort Cloud probably contains 0 1 to 2 trillion icy bodies in solar orbit Occasionally, giant molecular clouds, stars passing nearby, or tidal interactions with the Milky Way’s disc disturb the orbit of one of these bodies in the outer region of the Oort Cloud, causing the object to streak into the inner solar system as a so-called long-period comet These comets have very large
- In Depth | Perseids – NASA Solar System Exploration
The Comet The pieces of space debris that interact with our atmosphere to create the Perseids originate from comet 109P Swift-Tuttle Swift-Tuttle takes 133 years to orbit the Sun once It was Giovanni Schiaparelli who realized in 1865 that this comet was the source of the Perseids Comet Swift-Tuttle last visited the inner solar system in 1992
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