99942 Apophis

Apophis(99942) Apophis99942 Apophis Mission Design CompetitionApophis asteroid
99942 Apophis (, previously known by its provisional designation ) is a 370-metre-diameter near-Earth asteroid that caused a brief period of concern in December 2004 because initial observations indicated a probability of up to 2.7% that it would hit Earth on April 13, 2029.wikipedia
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Gravitational keyhole

However, until 2006, a possibility remained that during the 2029 close encounter with Earth, Apophis would pass through a gravitational keyhole, a small region no more than about 800 m in diameter, that would set up a future impact exactly seven years later on April 13, 2036.
It gained some public interest when it became clear, in January 2005, that the Asteroid 99942 Apophis would miss the Earth in 2029 but may go through one or another keyhole leading to impacts in 2036 or 2037.

Fabrizio Bernardi

F. Bernardi
Apophis was discovered on June 19, 2004, by Roy A. Tucker, David J. Tholen, and Fabrizio Bernardi at the Kitt Peak National Observatory.
Fabrizio Bernardi (born 1972) is an Italian astronomer and discoverer of minor planets and comets, best known for the co-discovery of the near-Earth and potentially hazardous asteroid 99942 Apophis.

Roy A. Tucker

R. A. TuckerRoy TuckerTucker
Apophis was discovered on June 19, 2004, by Roy A. Tucker, David J. Tholen, and Fabrizio Bernardi at the Kitt Peak National Observatory.
Roy A. Tucker (born 1951 in Jackson, Mississippi) is an American astronomer best known for the co-discovery of near-Earth asteroid 99942 Apophis (formerly known as ) along with David J. Tholen and Fabrizio Bernardi of the University of Hawaii.

Radar astronomy

radarRadar observationsradar telescope
Radar astrometry in January 2005 further refined its orbit solution.
This aids in forming long-term predictions of asteroid-Earth impacts, as illustrated by the object 99942 Apophis.

David J. Tholen

D. J. TholenDavid TholenTholen
Apophis was discovered on June 19, 2004, by Roy A. Tucker, David J. Tholen, and Fabrizio Bernardi at the Kitt Peak National Observatory.
He co-discovered the asteroid 99942 Apophis (previously known as ).

NEODyS

Six months after discovery, and shortly after a close approach to Earth on December 21, 2004, the improved orbital estimates led to the prediction of a very close approach on April 13, 2029 by both NASA's automatic Sentry system and NEODyS, a similar automatic program run by the University of Pisa and the University of Valladolid.

B612 Foundation

B612Clark ChapmanDaniel David Durda
In July 2005, former Apollo astronaut Rusty Schweickart, as chairman of the B612 Foundation, formally asked NASA to investigate the possibility that the asteroid's post-2029 orbit could be in orbital resonance with Earth, which would increase the probability of future impacts. In 2008, the B612 Foundation made estimates of Apophis's path if a 2036 Earth impact were to occur, as part of an effort to develop viable deflection strategies.
In December 2009 Roscosmos Russian Federal Space Agency director Anatoly Perminov proposed a deflection mission to the 325 metres (1,066 ft) wide asteroid 99942 Apophis, which at the time had been thought to pose a risk of collision with Earth.

Apep

ApophisAapepserpent deity
Apophis is the Greek name of Apep, an enemy of the Ancient Egyptian sun-god Ra.

Asteroid impact avoidance

planetary defenseAsteroid deflection strategiesNEOShield
In 2008, the B612 Foundation made estimates of Apophis's path if a 2036 Earth impact were to occur, as part of an effort to develop viable deflection strategies.
For example, it was estimated there was a high chance of 99942 Apophis swinging by Earth in 2029 with a 10 −4 probability of passing through a 'keyhole' and returning on an impact trajectory in 2035 or 2036.

List of Stargate SG-1 characters

AsgardAnubisApophis
One of the show's persistent villains is an alien named Apophis.
The astronomers David J. Tholen and Roy A. Tucker enjoyed the character so much that they named a near-Earth asteroid that they co-discovered in 2004, 99942 Apophis.

Nico Marquardt

In April 2008, at the age of 13, he took part in the competition Jugend forscht with his research paper „The Killer Asteroid 99942 Apophis“, in which he calculated the probability for the asteroid Apophis to collide with a geosynchronous satellite and the consequences of this event to the likelihood of an Earth-collision.

Sentry (monitoring system)

Sentry Risk TableSentryScout
Six months after discovery, and shortly after a close approach to Earth on December 21, 2004, the improved orbital estimates led to the prediction of a very close approach on April 13, 2029 by both NASA's automatic Sentry system and NEODyS, a similar automatic program run by the University of Pisa and the University of Valladolid. Using observations through February 26, 2014, the odds of an impact on April 12, 2068, as calculated by the JPL Sentry risk table are 1 in 150,000.
Numbered notable objects with observation arcs of several years include: (29075) 1950 DA, 99942 Apophis, 101955 Bennu, and (410777) 2009 FD.

Stargate SG-1

SG-1Stargate SG1Stargate: SG-1
Tholen and Tucker, two of the co-discoverers of the asteroid, are reportedly fans of the television series Stargate SG-1.
The astronomers David J. Tholen and Roy A. Tucker enjoyed the SG-1 arch villain Apophis so much that they named their discovered near-Earth asteroid "99942 Apophis".

Aten asteroid

ATEAten groupAten
During the approach, Earth will perturb Apophis from an Aten-class orbit with a semi-major axis of 0.92 AU to an Apollo-class orbit with a semi-major axis of 1.1 AU.
For a brief time near the end of 2004, the asteroid 99942 Apophis (then known only by its provisional designation ) apparently posed a threat of impacting Earth in 2029 or 2036, but earlier observations were found that eliminated those possibilities.

Rusty Schweickart

Russell SchweickartRussell L. SchweickartRusty Schweikart
In July 2005, former Apollo astronaut Rusty Schweickart, as chairman of the B612 Foundation, formally asked NASA to investigate the possibility that the asteroid's post-2029 orbit could be in orbital resonance with Earth, which would increase the probability of future impacts.
In May 2005 Schweickart testified before the U.S. Congress on the dangers of an asteroid impact related to 99942 Apophis.

Rage (video game)

Rage RageRage 2
Rage is set in a post-apocalyptic near future, following the impact of the asteroid 99942 Apophis on Earth.

SpaceWorks Enterprises

SpaceWorks Enterprises, Inc.SpaceWorksSpaceWorks Enterprises, Inc
The commercial competition was won by a design called 'Foresight' created by SpaceWorks Enterprises, Inc. SpaceWorks proposed a simple orbiter with only two instruments and a radio beacon at a cost of ~US$140 million, launched aboard a Minotaur IV between 2012 and 2014, to arrive at Apophis five to ten months later.

The Profit of Doom

The lyrics refer to the asteroid 99942 Apophis; which, at that time, was said to have a possibility of hitting the Earth on Friday, April 13th, 2029.

Apocalyptic and post-apocalyptic fiction

post-apocalypticapocalypticpost-apocalyptic fiction
In id Software's video game Rage (2011), Earth is heavily damaged, and humanity nearly wiped out, by the direct collision of the real asteroid 99942 Apophis with the Earth in the year 2029.

Near-Earth object

near-Earth asteroidNEOnear-Earth
99942 Apophis (, previously known by its provisional designation ) is a 370-metre-diameter near-Earth asteroid that caused a brief period of concern in December 2004 because initial observations indicated a probability of up to 2.7% that it would hit Earth on April 13, 2029.
On December 24, 2004, 370 m asteroid 99942 Apophis (at the time known by its provisional designation ) was assigned a 4 on the Torino scale, the highest rating ever given, as there was a 2.7% chance of Earth impact on April 13, 2029.

(175706) 1996 FG3

1757061996 FG3
The whole mission will include exploration and close study of three asteroids by sending a probe to fly side by side with Apophis for a period to conduct close observation, and land on the asteroid 1996 FG3 to conduct in situ sampling analysis on the surface.
The mission includes plans for fly-by of three asteroids (one of them is 99942 Apophis), and land on to conduct in situ sampling analysis on the surface, according to Ji Jianghui, a researcher at the Purple Mountain Observatory of the Chinese Academy of Sciences and a member of the expert committee for scientific goal argumentation of deep space exploration in China.

Don Quijote (spacecraft)

Don QuijoteDon Quijote mission concept
Apophis is one of two asteroids that were considered by the European Space Agency as the target of its Don Quijote mission concept to study the effects of impacting an asteroid.
The former would have been targeted to the Amor asteroid 2003 SM84, the latter to the asteroid 99942 Apophis.

Provisional designation in astronomy

survey designationprovisional designationDesignation
99942 Apophis (, previously known by its provisional designation ) is a 370-metre-diameter near-Earth asteroid that caused a brief period of concern in December 2004 because initial observations indicated a probability of up to 2.7% that it would hit Earth on April 13, 2029.

Earth

Earth's surfaceterrestrialworld
99942 Apophis (, previously known by its provisional designation ) is a 370-metre-diameter near-Earth asteroid that caused a brief period of concern in December 2004 because initial observations indicated a probability of up to 2.7% that it would hit Earth on April 13, 2029.

Impact event

impactmeteorite impactasteroid impact
Additional observations provided improved predictions that eliminated the possibility of an impact on Earth or the Moon in 2029.