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EPOXI
''EPOXI'' was a compilation of NASA Discovery program missions led by the University of Maryland and principal investigator Michael A'Hearn, with co-operation from the Jet Propulsion Laboratory and Ball Aerospace. ''EPOXI'' uses the '' Deep Impact'' spacecraft in a campaign consisting of two missions: the ''Deep Impact Extended Investigation'' (DIXI) and ''Extrasolar Planet Observation and Characterization'' (EPOCh). ''DIXI'' aimed to send the ''Deep Impact'' spacecraft on a flyby of another comet, after its primary mission was completed in July 2005, while ''EPOCh'' saw the spacecraft's photographic instruments as a space observatory, studying extrasolar planets. ''DIXI'' successfully sent the ''Deep Impact'' spacecraft on a flyby of comet Hartley 2 on November 4, 2010, revealing a "hyperactive, small and feisty" comet, after three gravity assists from Earth in December 2007, December 2008 and June 2010. The ''DIXI'' mission was not without problems, however; the spacecraf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EPOXI Moon Transits Earth
''EPOXI'' was a compilation of NASA Discovery program missions led by the University of Maryland, College Park, University of Maryland and principal investigator Michael A'Hearn, with co-operation from the Jet Propulsion Laboratory and Ball Aerospace & Technologies Corp., Ball Aerospace. ''EPOXI'' uses the ''Deep Impact (spacecraft), Deep Impact'' spacecraft in a campaign consisting of two missions: the ''Deep Impact Extended Investigation'' (DIXI) and ''Extrasolar Planet Observation and Characterization'' (EPOCh). ''DIXI'' aimed to send the ''Deep Impact'' spacecraft on a flyby of another comet, after its primary mission was completed in July 2005, while ''EPOCh'' saw the spacecraft's photographic instruments as a space observatory, studying extrasolar planets. ''DIXI'' successfully sent the ''Deep Impact'' spacecraft on a Flyby (spaceflight), flyby of comet 103P/Hartley, Hartley 2 on November 4, 2010, revealing a "hyperactive, small and feisty" comet, after three gravity assist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Impact (spacecraft)
''Deep Impact'' was a NASA space probe launched from Cape Canaveral Air Force Station on January 12, 2005. It was designed to study the interior composition of the comet Tempel 1 (9P/Tempel), by releasing an Deliberate crash landings on extraterrestrial bodies, impactor into the comet. At 05:52 UTC on July 4, 2005, the Impactor successfully collided with the comet's comet nucleus, nucleus. The impact excavated debris from the interior of the nucleus, forming an impact crater. Photographs taken by the spacecraft showed the comet to be more dusty and less icy than had been expected. The impact generated an unexpectedly large and bright dust cloud, obscuring the view of the impact crater. Previous space missions to comets, such as ''Giotto mission, Giotto'', ''Deep Space 1'', and ''Stardust (spacecraft), Stardust'', were Flyby (spaceflight), fly-by missions. These missions were able to photograph and examine only the surfaces of cometary nuclei, and even then from considerable dista ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
103P/Hartley
Comet Hartley 2, designated as 103P/Hartley by the Minor Planet Center, is a small periodic comet with an orbital period of 6.48 years. It was discovered by Malcolm Hartley in 1986 at the Schmidt Telescope Unit, Siding Spring Observatory, Australia. Its diameter is estimated to be Hartley 2 was the target of a flyby of the '' Deep Impact'' spacecraft, as part of the EPOXI mission, on 4 November 2010, which was able to approach within of Hartley 2 as part of its extended mission. Hartley 2 is the smallest comet which has been visited. It is the fifth comet visited by spacecraft, and the second comet visited by the Deep Impact spacecraft, which first visited comet Tempel 1 on 4 July 2005. Discovery and orbit Comet Hartley 2 is a small Jupiter-family comet having an orbital period of 6.46 years. It was discovered by Malcolm Hartley in 1986 at the Schmidt Telescope Unit, Siding Spring Observatory, Australia. It has the perihelion near the Earth's orbit at from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discovery Program
The Discovery Program is a series of Solar System exploration missions funded by the U.S. National Aeronautics and Space Administration (NASA) through its Planetary Missions Program Office. The cost of each mission is capped at a lower level than missions from NASA's New Frontiers program, New Frontiers or Flagship Program, Flagship Programs. As a result, Discovery missions tend to be more focused on a specific scientific goal rather than serving a general purpose. The Discovery Program was founded in 1990. Existing NASA programs had specified mission targets and objectives in advance, then sought bidders to construct and operate them. In contrast, Discovery missions are solicited through a call for proposals on any science topic and assessed through peer review. Selected missions are led by a scientist called the principal investigator (PI) and may include contributions from industry, universities or government laboratories. The Discovery Program also includes Missions of Opp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comet Boethin
Comet Boethin (officially 85D/Boethin) was a periodic Jupiter-family comet discovered in 1975 by Leo Boethin. It appeared again in January 1986 as expected. Although the comet was next expected at perihelion in April 1997, no observations were reported, and the comet is thought to have disintegrated. It has not been observed since March 1986. The comet might have come to perihelion in late July 2020, but the uncertainty in the comet's position is hundreds of millions of km. The old orbit would have the comet next coming to perihelion around November 2031. Discovery circumstances The comet was discovered under unusual circumstances. Comet 85D/Boethin was the first comet discovered by an observer in the Philippines. Leo Boethin (1912-1998), who was assigned as Reverend of the Abra province in 1949, had taken advantage of the exceptionally dark skies of Luzon to observe comets and meteor showers. In January 1973, he found his first suspected comet at magnitude 9.5, but he saw it fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flyby (spaceflight)
A flyby () is a spaceflight operation in which a spacecraft passes in proximity to another body, usually a target of its space exploration mission and/or a source of a gravity assist (also called ''swing-by'') to impel it towards another target. 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. Important parameters are the time and distance of closest approach. Spacecraft flyby Flyby maneuvers can be conducted with a planet, a natural satellite or a non-planetary object such as a small Solar System body. Planetary flybys have occurred with Mars or Earth for example: * List of Earth flybys * Mars flyby An example of a comet flyby is when International Cometary Explorer (formerly ISEE-3) passed about from the nucleus of Comet Giacobini-Zinner in September 1985. Another application of the flyby is of Earth's Moon, usually called a lunar flyby. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michael A'Hearn
Michael Francis A'Hearn (November 17, 1940 – May 29, 2017) was an American astronomer and astronomy professor at the University of Maryland College of Computer, Mathematical, and Natural Sciences. He was also the principal investigator for NASA's EPOXI mission. Career He received his B.A. in science at Boston College and his Ph.D. in Astronomy at the University of Wisconsin–Madison. He was the principal investigator for the NASA '' Deep Impact'' mission. He aided in the development of systems for surveying abundances in comets as well as techniques for determining the sizes of cometary nuclei which uses optical and infrared measurements. His studies focused on comets as well as asteroids and he also supervises numerous graduate students. He was an elected fellow of the AAAS. He authored over 100 papers published in journals and was also an avid sailor who had a commercial coast guard license. In June 1986, the main-belt asteroid 3192 A'Hearn, discovered by American ast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
9P/Tempel
Tempel 1 (official designation: 9P/Tempel) is a periodic Jupiter-family comet discovered by Wilhelm Tempel in 1867. It completes an orbit of the Sun every 5.6 years. Tempel 1 was the target of the ''Deep Impact'' space mission, which photographed a deliberate high-speed impact upon the comet in 2005. It was re-visited by the ''Stardust'' spacecraft on 14 February 2011, and came back to perihelion in August 2016. On 26 May 2024, it made a modest approach to Jupiter at a distance of which will lift the perihelion distance and 9P will next come to perihelion on 12 February 2028 when it will be from the Sun. Discovery and orbital history Tempel 1 was discovered on April 3, 1867, by Wilhelm Tempel, who was working at Marseille. At the time of discovery, it approached perihelion once every 5.68 years (designations P/1867 G1 and 1867 II). It was subsequently observed in 1873 (P/1873 G1, 1873 I, 1873a) and in 1879 (1879 III, 1879b). Photographic attempts during 1898 and 1905 failed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methods Of Detecting Extrasolar Planets
Methods of detecting exoplanets usually rely on indirect strategies – that is, they do not directly image the planet but deduce its existence from another signal. Any planet is an extremely faint light source compared to its parent star. For example, a star like the Sun is about a billion times as bright as the reflected light from any of the planets orbiting it. In addition to the intrinsic difficulty of detecting such a faint light source, the glare from the parent star washes it out. For those reasons, very few of the exoplanets reported have been detected directly, with even fewer being resolved from their host star. Established detection methods The following methods have proven successful at least once for discovering a new planet or detecting an already discovered planet: Radial velocity A star with a planet will move in its own small orbit in response to the planet's gravity. This leads to variations in the speed with which the star moves toward or away from Ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth
Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all of Earth's water is contained in its global ocean, covering Water distribution on Earth, 70.8% of Earth's crust. The remaining 29.2% of Earth's crust is land, most of which is located in the form of continental landmasses within Earth's land hemisphere. Most of Earth's land is at least somewhat humid and covered by vegetation, while large Ice sheet, sheets of ice at Polar regions of Earth, Earth's polar polar desert, deserts retain more water than Earth's groundwater, lakes, rivers, and Water vapor#In Earth's atmosphere, atmospheric water combined. Earth's crust consists of slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Earth's outer core, Earth has a liquid outer core that generates a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tempel 1
Tempel 1 (official designation: 9P/Tempel) is a periodic Jupiter-family comet discovered by Wilhelm Tempel in 1867. It completes an orbit of the Sun every 5.6 years. Tempel 1 was the target of the ''Deep Impact'' space mission, which photographed a deliberate high-speed impact upon the comet in 2005. It was re-visited by the ''Stardust'' spacecraft on 14 February 2011, and came back to perihelion in August 2016. On 26 May 2024, it made a modest approach to Jupiter at a distance of which will lift the perihelion distance and 9P will next come to perihelion on 12 February 2028 when it will be from the Sun. Discovery and orbital history Tempel 1 was discovered on April 3, 1867, by Wilhelm Tempel, who was working at Marseille. At the time of discovery, it approached perihelion once every 5.68 years (designations P/1867 G1 and 1867 II). It was subsequently observed in 1873 (P/1873 G1, 1873 I, 1873a) and in 1879 (1879 III, 1879b). Photographic attempts during 1898 and 1905 fai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
