Occulting disk

Last updated
A debris disk around the star AU Microscopii. The black circle in the center is an occulting disk of a coronagraph. Debris disk AU Mic HST.jpg
A debris disk around the star AU Microscopii. The black circle in the center is an occulting disk of a coronagraph.

An occulting disk is a small disk placed centrally in the eyepiece of a telescope or at its focal point, to block the view of a bright object so that fainter objects can be seen more easily. [1] [2]

The coronagraph, at its simplest, is an occulting disk in the focal plane of a telescope, or in front of the entrance aperture, that blocks out the image of the solar disk, so that the corona can be seen. Starshade is one designed to fly in formation with a space telescope to image exoplanets.

See also

Related Research Articles

<span class="mw-page-title-main">Amateur astronomy</span> Hobby of watching the sky and stars

Amateur astronomy is a hobby where participants enjoy observing or imaging celestial objects in the sky using the unaided eye, binoculars, or telescopes. Even though scientific research may not be their primary goal, some amateur astronomers make contributions in doing citizen science, such as by monitoring variable stars, double stars, sunspots, or occultations of stars by the Moon or asteroids, or by discovering transient astronomical events, such as comets, galactic novae or supernovae in other galaxies.

<span class="mw-page-title-main">Very Large Telescope</span> Telescope in the Atacama Desert, Chile

The Very Large Telescope (VLT) is a facility operated by the European Southern Observatory, located on Cerro Paranal in the Atacama Desert of northern Chile. It consists of four individual telescopes, each equipped with a primary mirror that measures 8.2 meters in diameter. These optical telescopes, named Antu, Kueyen, Melipal, and Yepun, are generally used separately but can be combined to achieve a very high angular resolution. The VLT array is also complemented by four movable Auxiliary Telescopes (ATs) with 1.8-meter apertures.

<span class="mw-page-title-main">Astronomical transit</span> Term in astronomy

In astronomy, a transit is the passage of a celestial body directly between a larger body and the observer. As viewed from a particular vantage point, the transiting body appears to move across the face of the larger body, covering a small portion of it.

<span class="mw-page-title-main">Optical telescope</span> Telescope for observations with visible light

An optical telescope is a telescope that gathers and focuses light mainly from the visible part of the electromagnetic spectrum, to create a magnified image for direct visual inspection, to make a photograph, or to collect data through electronic image sensors.

<span class="mw-page-title-main">Occultation</span> Occlusion of an object by another object that passes between it and the observer

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 when foreground objects obscure distant objects dynamically, as the scene changes over time.

<span class="mw-page-title-main">Spitzer Space Telescope</span> Infrared space telescope - 2003 to Jan 2020

The Spitzer Space Telescope, formerly the Space Infrared Telescope Facility (SIRTF), was an infrared space telescope launched in 2003. Operations ended on 30 January 2020. Spitzer was the third space telescope dedicated to infrared astronomy, following IRAS (1983) and ISO (1995–1998). It was the first spacecraft to use an Earth-trailing orbit, later used by the Kepler planet-finder.

<span class="mw-page-title-main">Observational astronomy</span> Division of astronomy

Observational astronomy is a division of astronomy that is concerned with recording data about the observable universe, in contrast with theoretical astronomy, which is mainly concerned with calculating the measurable implications of physical models. It is the practice and study of observing celestial objects with the use of telescopes and other astronomical instruments.

<i>Gaia</i> (spacecraft) European optical space observatory for astrometry

Gaia is a space observatory of the European Space Agency (ESA), launched in 2013 and expected to operate until 2025. The spacecraft is designed for astrometry: measuring the positions, distances and motions of stars with unprecedented precision, and the positions of exoplanets by measuring attributes about the stars they orbit such as their apparent magnitude and color. The mission aims to construct by far the largest and most precise 3D space catalog ever made, totalling approximately 1 billion astronomical objects, mainly stars, but also planets, comets, asteroids and quasars, among others.

<span class="mw-page-title-main">Near Infrared Camera and Multi-Object Spectrometer</span>

The Near Infrared Camera and Multi-Object Spectrometer (NICMOS) is a scientific instrument for infrared astronomy, installed on the Hubble Space Telescope (HST), operating from 1997 to 1999, and from 2002 to 2008. Images produced by NICMOS contain data from the near-infrared part of the light spectrum.

<span class="mw-page-title-main">Coronagraph</span> Telescopic attachment designed to block out the direct light from a star

A coronagraph is a telescopic attachment designed to block out the direct light from a star or other bright object so that nearby objects – which otherwise would be hidden in the object's bright glare – can be resolved. Most coronagraphs are intended to view the corona of the Sun, but a new class of conceptually similar instruments are being used to find extrasolar planets and circumstellar disks around nearby stars as well as host galaxies in quasars and other similar objects with active galactic nuclei (AGN).

<span class="mw-page-title-main">2M1207b</span> Planetary-mass object orbiting the brown dwarf 2M1207

2M1207b is a planetary-mass object orbiting the brown dwarf 2M1207, in the constellation Centaurus, approximately 170 light-years from Earth. It is one of the first candidate exoplanets to be directly observed. It was discovered in April 2004 by the Very Large Telescope (VLT) at the Paranal Observatory in Chile by a team from the European Southern Observatory led by Gaël Chauvin. It is believed to be from 5 to 6 times the mass of Jupiter and may orbit 2M1207 at a distance roughly as far from the brown dwarf as Pluto is from the Sun.

<span class="mw-page-title-main">New Worlds Mission</span> Proposed occulter

The New Worlds Mission is a proposed project comprising a large occulter flying in formation with a space telescope designed to block the light of nearby stars in order to observe their orbiting exoplanets. The observations could be taken with an existing space telescope or a dedicated visible light optical telescope optimally designed for the task of finding exoplanets. A preliminary research project was funded from 2005 through 2008 by NASA Institute for Advanced Concepts (NIAC) and headed by Webster Cash of the University of Colorado at Boulder in conjunction with Ball Aerospace & Technologies Corp., Northrop Grumman, Southwest Research Institute and others. Since 2010 the project has been looking for additional financing from NASA and other sources in the amount of roughly US$3 billion including its own four-meter telescope. If financed and launched, it would operate for five years.

<span class="mw-page-title-main">Lists of exoplanets</span>

These are lists of exoplanets. As of 24 August 2023, there are 5,502 confirmed exoplanets in 4,096 planetary systems, with 928 systems having more than one planet. Most of these were discovered by the Kepler space telescope. There are an additional 1,984 potential exoplanets from Kepler's first mission yet to be confirmed, as well as 977 from its "Second Light" mission and 4,476 from the Transiting Exoplanet Survey Satellite (TESS) mission.

<span class="mw-page-title-main">Methods of detecting exoplanets</span>

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 light from the parent star causes a glare that washes it out. For those reasons, very few of the exoplanets reported as of April 2014 have been observed directly, with even fewer being resolved from their host star.

Telescope for Habitable Exoplanets and Interstellar/Intergalactic Astronomy (THEIA) is a NASA-proposed 4-metre optical/ultraviolet space telescope that would succeed the Hubble Space Telescope and complement the infrared-James Webb Space Telescope. THEIA would use a 40-metre occulter to block starlight so as to directly image exoplanets.

<span class="mw-page-title-main">Nancy Grace Roman Space Telescope</span> NASA infrared space telescope scheduled to launch in 2027

The Nancy Grace Roman Space Telescope is a NASA infrared space telescope in development and scheduled to launch by May 2027.

<span class="mw-page-title-main">CHEOPS</span> Optical space telescope (launched in 2019)

CHEOPS is a European space telescope. Its objective is to determine the size of known extrasolar planets, which will allow the estimation of their mass, density, composition and their formation. Launched on 18 December 2019, it is the first Small-class mission in ESA's Cosmic Vision science programme.

<span class="mw-page-title-main">Large Ultraviolet Optical Infrared Surveyor</span> Proposed NASA space telescope

The Large Ultraviolet Optical Infrared Surveyor, commonly known as LUVOIR, is a multi-wavelength space telescope concept being developed by NASA under the leadership of a Science and Technology Definition Team. It is one of four large astrophysics space mission concepts studied in preparation for the National Academy of Sciences 2020 Astronomy and Astrophysics Decadal Survey.

<span class="mw-page-title-main">ASTERIA (spacecraft)</span> CubeSat testing technologies for the detection of exoplanets

ASTERIA was a miniaturized space telescope technology demonstration and opportunistic science mission to conduct astrophysical measurements using a CubeSat. It was designed in collaboration between the Massachusetts Institute of Technology (MIT) and NASA's Jet Propulsion Laboratory. ASTERIA was the first JPL-built CubeSat to have been successfully operated in space. Originally envisioned as a project for training early career scientists and engineers, ASTERIA's technical goal was to achieve arcsecond-level line-of-sight pointing error and highly stable focal plane temperature control. These technologies are important for precision photometry, i.e., the measurement of stellar brightness over time. Precision photometry, in turn, provides a way to study stellar activity, transiting exoplanets, and other astrophysical phenomena.

References

  1. "Occulting disk - Oxford Reference". Oxford Reference. Oxford University Press. Retrieved 28 August 2023.
  2. Ridpath, Ian (2012). A Dictionary of Astronomy. Oxford University Press. p. 336. ISBN   9780199609055 . Retrieved 28 August 2023.