Flyby (spaceflight)

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Diagram of the trajectory of New Horizons during its flyby of Pluto
Imagery collected by Voyager 2 of Ganymede during its flyby of the Jovian system

Flyby is a spacecraft concept whereby one object passes in closer proximity to another, usually a spacecraft maneuver in space exploration.[1] Spacecraft which are specifically designed for this purpose are known as flyby spacecraft, although the term has also been used in regard to asteroid flybys of Earth for example.[2][3] Two common goals are for exploration or for a gravity assist.

One important subconcept of a flyby in spaceflight, is the time and distance of closest approach.[4] This distance is often reported, along with a time in regards to flybys in space.[5]

Spacecraft flyby[edit]

Flyby maneuvers can be conducted with a planet or non-planet object such as a comet.[6][7][8]

Planetary flybys have occurred with with Mars or Earth for example:

An example of a comet flyby is when International Cometary Explorer (formerly ISEE-3) passed about 4800 miles (7,800 kilometers) from the nucleus of Comet Giacobini-Zinner in September 1985.[9]

The New Horizons spacecraft is planning to flyby the Kuiper belt object 2014 MU69 on New Year's Day 2019, after its successful flyby of the dwarf planet Pluto in 2015.[10]

Another application of the flyby is of Earth's moon, usually called a lunar flyby.[11]

In regards to Mars flybys, a related concept is a Mars flyby rendezvous, where a spacecraft does not enter orbit but rendezvous before or after a flyby of the planet with another spacecraft.[12] Mars flyby rendezvous was evaluated at NASA's Manned Spacecraft Center in the 1960s.[12] At that time NASA developed designs for a combination of a Mars lander, short-stay surface habitat, and ascent vehicle called a Mars Excursion Module (MEM); the ascent stage performed the rendezvous with another spacecraft that did a flyby of Mars without entering orbit or landing.[12] Compared to MOR, a flyby rendezvous means one spacecraft does not have to orbit Mars, so the resources needed on a return journey to Earth are not taken in and out of Mars orbit for example.[12] (See also Mars cycler)

Cassini-Huygens (launched 1997), which orbited Saturn (from 2004-2017) performed flybys of many of Saturn's moons including Titan.[13] Cassini-Huygen's had its first flyby of Titan in October 2004.[14] For further examples of Cassini flybys of Saturn's moons see Timeline of Cassini–Huygens.

Animation of Cassini spacecraft trajectory around Saturn over 10 years, and during this time it passed closely by many moons of Saturn:

Animation of Cassini's trajectory around Saturn from 1 May 2004 to 1 May 2014
   Cassini ·   Saturn ·   Enceladus ·    Titan ·    Iapetus
Flyby of comet Hartley 2 on Nov. 4, 2010 (EPOXI mission)

Natural flyby[edit]

During an asteroid flyby of Earth, sometimes they are observed by Radar imaging. Animation of 2014 JO25, which had a Earth flyby in 2017

Flyby is also commonly used to describe when, for example, an asteroid approaches and coasts by the Earth.[15][16]

This was also the term for when a comet did a flyby of Mars in 2014.[17]

P/2016 BA14 was radar imaged at distance of 2.2 million miles (9 lunar distances) from Earth in 2016, during its flyby.[18] This enabled the size of the nucleus to be calculated to about 1 km in diameter.[19]

See also[edit]

References[edit]

  1. ^ "Basics of Space Flight - Solar System Exploration: NASA Science". Solar System Exploration: NASA Science. Retrieved 2018-11-04.
  2. ^ "Basics of Space Flight - Solar System Exploration: NASA Science". Solar System Exploration: NASA Science. Retrieved 2018-11-04.
  3. ^ "'Tunguska'-Size Asteroid Makes Surprise Flyby of Earth". Space.com. Retrieved 2018-11-04.
  4. ^ "Titan A Flyby Closest Approach". sci.esa.int. Retrieved 2018-11-04.
  5. ^ "Titan A Flyby Closest Approach". sci.esa.int. Retrieved 2018-11-04.
  6. ^ "Our SpaceFlight Heritage: ICE—The first comet flyby". SpaceFlight Insider. 2018-09-12. Retrieved 2018-11-04.
  7. ^ "First mission to Mars: Mariner 4's special place in history | Cosmos". cosmosmagazine.com. Retrieved 2018-11-04.
  8. ^ "First mission to Mars: Mariner 4's special place in history | Cosmos". cosmosmagazine.com. Retrieved 2018-11-04.
  9. ^ "Our SpaceFlight Heritage: ICE—The first comet flyby". SpaceFlight Insider. 2018-09-12. Retrieved 2018-11-04.
  10. ^ "2014 MU69: Next Target for New Horizons". Space.com. Retrieved 2018-11-04.
  11. ^ "SpaceX says its BFR will fly someone around the Moon; we have questions". Ars Technica. Retrieved 2018-11-04.
  12. ^ a b c d Portree, David S. F. (February 2001). "Chapter 3: EMPIRE and After". Humans to Mars: Fifty Years of Mission Planning, 1950 - 2000 (PDF). NASA Monographs in Aerospace History Series. National Aeronautics and Space Administration. pp. 15–16. Retrieved July 18, 2014.
  13. ^ "Titan A Flyby Closest Approach". sci.esa.int. Retrieved 2018-11-04.
  14. ^ "Titan A Flyby Closest Approach". sci.esa.int. Retrieved 2018-11-04.
  15. ^ "Two Small Asteroids Are Buzzing Earth This Weekend. See One Live Tonight!". Space.com. Retrieved 2018-11-04.
  16. ^ "Asteroid seen after it makes the closest flyby of the year". CNET. 2018-08-13. Retrieved 2018-11-04.
  17. ^ "Comet's 2014 Mars Flyby Caused Most Intense Meteor Shower Ever Recorded". Space.com. Retrieved 2018-11-04.
  18. ^ "Flyby Comet Was WAY Bigger Than Thought". Space.com. Retrieved 2018-11-07.
  19. ^ "Flyby Comet Was WAY Bigger Than Thought". Space.com. Retrieved 2018-11-07.

External links[edit]