An occultation is an event that occurs when one object is hidden from the observer by another object that passes between them. 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 (or computer-generated imagery ) when foreground objects obscure distant objects dynamically, as the scene changes over time.
27-432: Stellina may refer to: Stellina (astronomy) , a digital electronic telescope Stellina (liqueur) , an herbal liqueur Stellina (TV series) , an Italian animated television series Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Stellina . If an internal link led you here, you may wish to change
54-1023: A Bahtinov mask and a protective cap. Later, Unistellar introduced two new telescopes, eVscope 2 with bigger FOV and better monitor which won the T3 Platinum Award, and eQuinox with longer battery life and no monitor. As presented in AGU 2021 Fall Meeting, the eVscope had observed many astronomical objects up to December 2021, including the detection by 79 observers of 85 transits by Jupiter-sized exoplanets, 281 asteroid occultations (including forty-five positive ones), and three shape and spin solutions for near-Earth asteroids. The network also supported NASA's TESS mission by making transatlantic observations of an exoplanet transit, and NASA's Lucy mission by profiling Trojan asteroids this spacecraft will visit. These data are collected by observers in Europe, North America, Japan, Australia, and New Zealand. Unistellar aims to expand
81-515: A solar eclipse . Therefore, a total solar eclipse is essentially the Moon occulting the Sun. Stars may also be occulted by planets. Occultations of bright stars are rare. In 1959, Venus occulted Regulus , and the next occultation of a bright star (also Regulus by Venus) will be in 2044. Uranus 's rings were first discovered when that planet occulted a star in 1977. On 3 July 1989, Saturn passed in front of
108-501: A space telescope , most likely positioned near the Earth 's L 2 Lagrangian point . The second would place the satellite in a highly elliptical orbit about the Earth, and work in conjunction with a ground telescope. At the apogee of the orbit, the satellite would remain relatively stationary with respect to the ground, allowing longer exposure times. An updated version of this design is called
135-466: A few tenths of a second have various scientific uses, particularly in refining our knowledge of lunar topography . Photoelectric analysis of lunar occultations have also discovered some stars to be very close visual or spectroscopic binaries . Some angular diameters of stars have been measured by timing of lunar occultations, which is useful for determining effective temperatures of those stars. Early radio astronomers found occultations of radio sources by
162-422: A primary and its satellite . A large number of moons have been discovered analyzing the photometric light curves of small bodies and detecting a second, superimposed brightness variation, from which an orbital period for the satellite (secondary), and a secondary-to-primary diameter-ratio (for the binary system ) can often be derived. The Moon or another celestial body can occult multiple celestial bodies at
189-400: Is a similar technology-facilitated telescope that uses a digital display in lieu of an eyepiece and stacks images to get high-resolution images of deep-sky objects . Asteroid occultation If the closer body does not entirely conceal the farther one, the event is called a transit . Both transit and occultation may be referred to generally as occlusion ; and if a shadow is cast onto
216-414: Is inclined slightly with respect to the ecliptic (see orbit of the Moon ) meaning any star with an ecliptic latitude between –6.6 and +6.6 degrees may be occulted by it. Three first magnitude stars appear well within that band – Regulus , Spica , and Antares – meaning they may be occulted by the Moon or by planets. Occultations of Aldebaran are in this epoch only possible by the Moon, because
243-478: Is transmitted to a small screen in an eyepiece also mounted on the telescope. An electronic connection to a computer ( smartphone , pad , or laptop) is required to make astronomical observations from the telescope. The digital technology allows multiple images to be stacked while subtracting the noise component of the observation producing images of Messier objects and faint stars as dim as an apparent magnitude of 15 with consumer-grade equipment. The company
270-403: The 5th magnitude star 28 Sagittarii . Pluto occulted stars in 1988, 2002, and 2006, allowing its tenuous atmosphere to be studied via atmospheric limb sounding . In rare cases, one planet can pass in front of another. If the nearer planet appears larger than the more distant one, the event is called a mutual planetary occultation. The last occultation or transit occurred on 3 January 1818 and
297-410: The Moon valuable for determining their exact positions, because the long wavelength of radio waves limited the resolution available through direct observation. This was crucial for the unambiguous identification of the radio source 3C 273 with the optical quasar and its jet, and a fundamental prerequisite for Maarten Schmidt 's discovery of the cosmological nature of quasars . Several times during
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#1732880088454324-568: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Stellina&oldid=1140965787 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Stellina (astronomy) Unistellar is a French manufacturer of computer-connected telescopes that allow non-professional skywatchers to observe astronomical objects at relatively low cost. The first product launched
351-598: The network to the rest of Asia and to South America. The Unistellar Exoplanet (UE) campaign helped to improve the measurement accuracy of the orbital period of TOI 3799.01. The UE campaign also helps to refine the orbit of long-period exoplanets, such as the Jupiter-analog Kepler-167e and the eccentric planet HD 80606b , which have transit durations longer than 10 hours. This refinement will help with follow-up observations, such as JWST observation of HD 80606b. The Stellina astrophotography telescope by Vaonis
378-529: The next will occur on 22 November 2065, in both cases involving the same two planets— Venus and Jupiter . Jupiter rarely occults Saturn . This is one of the rarest events known, with the next occurrence on February 10, 7541. This event is visible worldwide since the duo would be positioned almost in opposition to the sun, in the border line between the constellations of Orion and Taurus . In some areas this occultation cannot be seen, but when viewed through even small telescopes, both gas giants appear to be in
405-463: The observer, it is called an eclipse . The symbol for an occultation, and especially a solar eclipse , is [REDACTED] (U+1F775 🝵). The term occultation is most frequently used to describe lunar occultations , those relatively frequent occasions when the Moon passes in front of a star during the course of its orbital motion around the Earth. Since the Moon, with an angular speed with respect to
432-467: The orbiting planets to be observed. The proposed satellite would have a dimension of 70 by 70 metres (230 ft × 230 ft), a mass of about 600 kg, and maneuver by means of an ion drive engine in combination with using the sheet as a light sail. Positioned at a distance of 100,000 km from the telescope, it would block more than 99.998% of the starlight. There are two possible configurations of this satellite. The first would work with
459-469: The planets pass Aldebaran to the north. Neither planetary nor lunar occultations of Pollux are currently possible, however several thousand years ago lunar occultations were possible. Some notably close deep-sky objects , such as the Pleiades , can be occulted by the Moon. Within a few kilometres of the edge of an occultation's predicted path, referred to as its northern or southern limit, an observer may see
486-406: The product to market. The consumer-grade electronic telescope was originally planned to be available in the "fall 2018" which subsequently shifted to "early 2019," then later in 2019. By January 2020, the telescope was expected to be shipped worldwide between May and August 2020. As of December 2021, over 5000 telescopes had been delivered to customers The kit included a custom tripod and mount,
513-411: The same part of view through the eyepiece. The last one occurred in 6857 B.C.E. A further set of occultations are those when a small Solar System body or dwarf planet passes in front of a star, temporarily blocking its light as seen from Earth. These occultations are useful for measuring the size and position of body much more precisely than can be done by other means. A cross-sectional profile of
540-505: The same time. Because of its relatively large angular diameter the Moon, at any given time, occults an indeterminate number of stars and galaxies. However the Moon occulting (obscuring) two bright objects (e.g. two planets or a bright star and a planet) simultaneously is extremely rare and can be seen only from a small part of the world: the last such event was on 23 April 1998 when it occulted Venus and Jupiter for observers on Ascension Island . The Big Occulting Steerable Satellite (BOSS)
567-432: The shape of a body can even be determined if a number of observers at different, nearby, locations observe the occultation. Occultations have been used to calculate the diameter of trans-Neptunian objects such as 2002 TX 300 , Ixion and Varuna . Software for coordinating observations is available for download at http://www.occultwatcher.net/ In addition, mutual occultation and eclipsing events can occur between
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#1732880088454594-436: The star intermittently disappearing and reappearing as the irregular limb of the Moon moves past the star, creating what is known as a grazing lunar occultation . From an observational and scientific standpoint, these "grazes" are the most dynamic and interesting of lunar occultations. The accurate timing of lunar occultations is performed regularly by (primarily amateur) astronomers. Lunar occultations timed to an accuracy of
621-437: The stars of 0.55 arcsec /s or 2.7 μrad/s, has a very thin atmosphere and stars have an angular diameter of at most 0.057 arcseconds or 0.28 μrad, a star that is occulted by the Moon will disappear or reappear in 0.1 seconds or less on the Moon's edge, or limb. Events that take place on the Moon's dark limb are of particular interest to observers, because the lack of glare allows easier observation and timing. The Moon's orbit
648-439: The year the Moon can be seen occulting a planet. Since planets, unlike stars, have significant angular sizes, lunar occultations of planets will create a narrow zone on Earth from which a partial occultation of the planet will occur. An observer located within that narrow zone could observe the planet's disk partly blocked by the slowly moving Moon. The same mechanism can be seen with the Sun, where observers on Earth will view it as
675-407: Was a proposed satellite that would work in conjunction with a telescope to detect planets around distant stars. The satellite consists of a large, very lightweight sheet, and a set of maneuvering thrusters and navigation systems. It would maneuver to a position along the line of sight between the telescope and a nearby star. The satellite would thereby block the radiation from the star, permitting
702-568: Was founded in Marseille , France, in 2015, with incubator investment from Incubateur Impulse and Pépinières d'Entreprises Innovantes with subsequent VC round capital from private investors and a VC firm named Brighteye Ventures. Unistellar unveiled their electronic telescope technology prototype in 2017 at CES2017 in Las Vegas and at IFA Next in Berlin. The company experienced difficulties bringing
729-528: Was named the eVscope, and used digital astrophotographic techniques. SETI Institute has partnered with Unistellar and will be able to send requests for information and notifications to users, and receive information about transient astronomical events . The eVscope is a 114 mm (4.5 in)-diameter Prime focus reflector, focal length 450 mm. It projects its image onto a 4.8 mm × 3.6 mm (0.19 in × 0.14 in) CMOS color sensor with 1.3 million pixels . The image
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