Anthony Wesley (born 1965 or 1966) [1] is an Australian computer programmer and amateur astronomer, known for his discoveries of the 2009 and 2010 Jupiter impact events.
Wesley was born in Glen Innes, Australia in 1965. [2] At as early as ten years old, he was given a small telescope, which sparked his interest in stargazing. [3] By 2003 Wesley had become involved in planetary photography. Over time his work became more focused on Jupiter, leading to his discoveries of the 2009 and 2010 impact events. [1] Prior to these discoveries, scientists did not believe impacts of this relatively small size could be observed from Earth. [2] Wesleys' work also brought to light the vital role amateur astronomers play in space discovery. [1] [4]
On 19 July 2009 at approximately 13:30, Wesley found fame after discovering a scar near Jupiter's south pole the size of the Pacific Ocean. [1] Wesley discovered the impact at approximately 13:30 UTC on On 19 July 2009 (almost exactly 15 years after the Jupiter impact of comet Shoemaker-Levy 9, or SL9), Wesley discovered an impact on Jupiter that caused a black spot in the planet's atmosphere. He was at his home observatory just outside Murrumbateman, New South Wales, Australia, using stacked images on a 36.8-centimetre (14.5 in) diameter reflecting telescope equipped with a low light machine vision video camera attached to the telescope. [5]
On 3 June 2010, Wesley was away from his home visiting a friend, when with a 37-centimetre (15 in) telescope he took an image of a small celestial object burning up in the Jupiter atmosphere. [2] The observed flash lasted about two seconds. [1] The object was believed to be an asteroid, making it the first image of a meteorite hitting a planet. [4]
The find was praised by NASA and fellow astronomers, who were under the impression that after the 1994 collision another would not be expected for several hundred years. [1] [4]
An asteroid is a minor planet of the inner Solar System. Historically, these terms have been applied to any astronomical object orbiting the Sun that did not resolve into a disc in a telescope and was not observed to have characteristics of an active comet such as a tail. As minor planets in the outer Solar System were discovered that were found to have volatile-rich surfaces similar to comets, these came to be distinguished from the objects found in the main asteroid belt. The term "asteroid" refers to the minor planets of the inner Solar System, including those co-orbital with Jupiter. Larger asteroids are often called planetoids.
Comet Shoemaker–Levy 9 was a comet that broke apart in July 1992 and collided with Jupiter in July 1994, providing the first direct observation of an extraterrestrial collision of Solar System objects. This generated a large amount of coverage in the popular media, and the comet was closely observed by astronomers worldwide. The collision provided new information about Jupiter and highlighted its possible role in reducing space debris in the inner Solar System.
Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth the mass of the Sun. Jupiter is the third-brightest natural object in the Earth's night sky after the Moon and Venus. It has been observed since pre-historic times and is named after the Roman god Jupiter, the king of the gods, because of its observed size.
The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes but much smaller than planets, called asteroids or minor planets. This asteroid belt is also called the main asteroid belt or main belt to distinguish it from other asteroid populations in the Solar System such as near-Earth asteroids and trojan asteroids.
A natural satellite, or moon, is, in the most common usage, an astronomical body that orbits a planet or minor planet.
An impact event is a collision between astronomical objects causing measurable effects. Impact events have physical consequences and have been found to regularly occur in planetary systems, though the most frequent involve asteroids, comets or meteoroids and have minimal effect. When large objects impact terrestrial planets such as the Earth, there can be significant physical and biospheric consequences, though atmospheres mitigate many surface impacts through atmospheric entry. Impact craters and structures are dominant landforms on many of the Solar System's solid objects and present the strongest empirical evidence for their frequency and scale.
A minor-planet moon is an astronomical object that orbits a minor planet as its natural satellite. As of February 2021, there are 424 minor planets known or suspected to have moons. Discoveries of minor-planet moons are important because the determination of their orbits provides estimates on the mass and density of the primary, allowing insights of their physical properties that is generally not otherwise possible.
An occultation is an event that occurs when one object is hidden by another object that passes between it and the observer. The term is often used in astronomy, but can also refer to any situation in which an object in the foreground blocks from view (occults) an object in the background. In this general sense, occultation applies to the visual scene observed from low-flying aircraft when foreground objects obscure distant objects dynamically, as the scene changes over time.
The Panoramic Survey Telescope and Rapid Response System located at Haleakala Observatory, Hawaii, US, consists of astronomical cameras, telescopes and a computing facility that is surveying the sky for moving or variable objects on a continual basis, and also producing accurate astrometry and photometry of already-detected objects. In January 2019 the second Pan-STARRS data release was announced. At 1.6 petabytes, it is the largest volume of astronomical data ever released.
The Wide-field Infrared Survey Explorer is a NASA infrared-wavelength astronomical space telescope launched in December 2009, and placed in hibernation mode in February 2011. It was re-activated in 2013. WISE discovered thousands of minor planets and numerous star clusters. Its observations also supported the discovery of the first Y Dwarf and Earth trojan asteroid.
2007 WD5 is an Apollo asteroid some 50 m (160 ft) in diameter and a Mars-crosser asteroid first observed on 20 November 2007, by Andrea Boattini of the Catalina Sky Survey. Early observations of 2007 WD5 caused excitement amongst the scientific community when it was estimated as having as high as a 1 in 25 chance of colliding with Mars on 30 January 2008. However, by 9 January 2008, additional observations allowed NASA's Near Earth Object Program (NEOP) to reduce the uncertainty region resulting in only a 1-in-10,000 chance of impact. 2007 WD5 most likely passed Mars at a distance of 6.5 Mars radii. Due to this relatively small distance and the uncertainty level of the prior observations, the gravitational effects of Mars on its trajectory are unknown and, according to Steven Chesley of NASA's Jet Propulsion Laboratory Near-Earth Object program, 2007 WD5 is currently considered 'lost' (see lost asteroids).
Heidi B. Hammel is a planetary astronomer who has extensively studied Neptune and Uranus. She was part of the team imaging Neptune from Voyager 2 in 1989. She led the team using the Hubble Space Telescope to view Shoemaker-Levy 9's impact with Jupiter in 1994. She has used the Hubble Space Telescope and the Keck Telescope to study Uranus and Neptune, discovering new information about dark spots, planetary storms and Uranus' rings. In 2002, she was selected as an interdisciplinary scientist for the James Webb Space Telescope.
Discovery and exploration of the Solar System is observation, visitation, and increase in knowledge and understanding of Earth's "cosmic neighborhood". This includes the Sun, Earth and the Moon, the major planets Mercury, Venus, Mars, Jupiter, Saturn, Uranus, and Neptune, their satellites, as well as smaller bodies including comets, asteroids, and dust.
The Solar System — our Sun's system of planets, moons, and smaller debris — is humankind's cosmic backyard. Small by factors of millions compared to interstellar distances, the spaces between the planets are daunting, but technologically surmountable.
A minor planet is "lost" when today's observers cannot find it because they can no longer accurately predict its location with targeted observations and await serendipitous survey observations. This happens if the orbital elements of a minor planet are not known accurately enough, typically because the observation arc for the object is too short. Many previously lost asteroids were rediscovered in the 1980s and 1990s, but many minor planets are still lost.
The 2009 Jupiter impact event, occasionally referred to as the Wesley impact, was a July 2009 impact event on Jupiter that caused a black spot in the planet's atmosphere. The impact area covered 190 million square kilometers, similar in area to the planet's Little Red Spot and approximately the size of the Pacific Ocean. The impactor is estimated to have been about 200 to 500 meters in diameter.
The 2010 Jupiter impact event was a bolide impact event on Jupiter by an object estimated to be about 8–13 metres (26–43 ft) in diameter. The impactor may have been an asteroid, comet, centaur, extinct comet, or temporary satellite capture.
An exoplanet is a planet located outside the Solar System. The first evidence of an exoplanet was noted as early as 1917, but was not recognized as such until 2016. No planet discovery has yet come from that evidence. However, the first scientific detection of an exoplanet began in 1988. Afterwards, the first confirmed detection came in 1992, with the discovery of several terrestrial-mass planets orbiting the pulsar PSR B1257+12. The first confirmation of an exoplanet orbiting a main-sequence star was made in 1995, when a giant planet was found in a four-day orbit around the nearby star 51 Pegasi. Some exoplanets have been imaged directly by telescopes, but the vast majority have been detected through indirect methods, such as the transit method and the radial-velocity method. As of 22 June 2021, there are 4,768 confirmed exoplanets in 3,527 planetary systems, with 783 systems having more than one planet. This is a list of the most notable discoveries.
P/2016 BA14 (Pan-STARRS) is a near-Earth object and periodic comet of the Jupiter family, that was radar imaged at distance of 2.2 million miles during a flyby of Earth in 2016. This enabled the size of the nucleus to be calculated to be about 3000 feet to 3300 ft (1 km) in diameter. Four noted aspects to BA14 are that it was discovered as an asteroid first, it was much bigger than expected going from perhaps 125 meters to 1000 meters, it was the closest approach by a comet since 1770, and finally, it has a very similar orbit as numbered comet 252P/LINEAR, and may be related to it.
Asteroid impact prediction is the prediction of the dates and times of asteroids impacting Earth, along with the locations and severities of the impacts.