The Large Ultraviolet Optical Infrared Surveyor, commonly known as LUVOIR (), is a multi-wavelength

space telescope A space telescope or space observatory is a telescope in outer space used to observe astronomical objects. Suggested by Lyman Spitzer in 1946, the first operational telescopes were the American Orbiting Astronomical Observatory, OAO-2 launch ...

concept being developed by

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the US federal government responsible for the civil List of government space agencies, space program ...

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 The Astronomy and Astrophysics Decadal Survey is a review of astronomy and astrophysics literature produced approximately every ten years by the National Research Council of the National Academy of Sciences in the United States. The report surve ...

. While LUVOIR is a concept for a general-purpose observatory, it has the key science goal of characterizing a wide range of exoplanets, including those that might be

habitable Habitability refers to the adequacy of an environment for human living. Where housing is concerned, there are generally local ordinances which define habitability. If a residence complies with those laws it is said to be habitable. In extreme e ...

. An additional goal is to enable a broad range of astrophysics, from the

reionization In the fields of Big Bang theory and cosmology, reionization is the process that caused matter in the universe to reionize after the lapse of the " dark ages". Reionization is the second of two major phase transitions of gas in the universe (t ...

epoch, through galaxy formation and evolution, to star and

planet formation The nebular hypothesis is the most widely accepted model in the field of cosmogony to explain the formation and evolution of the Solar System (as well as other planetary systems). It suggests the Solar System is formed from gas and dust orbitin ...

. Powerful imaging and spectroscopy observations of

Solar System The Solar System Capitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar ...

bodies would also be possible. LUVOIR would be a Large Strategic Science Mission and was considered for a development start sometime in the 2020s. The LUVOIR Study Team, under Study Scientist

Aki Roberge Dr Aki Roberge (born 1973) is a research astrophysicist at NASA’s Goddard Space Flight Center, where she is currently the Associate Director for Technology and Strategy. Her research focuses on observational studies of debris disks and plane ...

, has produced designs for two variants of LUVOIR: one with a 15.1 m diameter telescope mirror (LUVOIR-A) and one with an 8 m diameter mirror (LUVOIR-B). LUVOIR would be able to observe

ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation ...

, visible, and

near-infrared Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of Light, visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from ...

wavelengths of light. The Final Report on the 5-year LUVOIR mission concept study was publicly released on 26 August 2019. On 4 November 2021, the 2020 Astrophysics Decadal Survey recommended development of a "large (~6 m aperture) infrared/optical/ultraviolet (IR/O/UV) space telescope", with the science goals of searching for signatures of life on planets outside of the solar system and enabling a wide range of transformative astrophysics. Such a mission draws upon both the LUVOIR and HabEx mission concepts.

Background

In 2016, NASA began considering four different

concepts for future Large Strategic Science Missions. They are the

Habitable Exoplanet Imaging Mission The Habitable Exoplanet Observatory (HabEx) is a space telescope concept that would be optimized to search for and image Earth-size habitable exoplanets in the habitable zones of their stars, where liquid water can exist. HabEx would aim to ...

(HabEx), Large Ultraviolet Optical Infrared Surveyor (LUVOIR),

Lynx X-ray Observatory The Lynx X-ray Observatory (''Lynx'') is a NASA-funded Large Mission Concept Study commissioned as part of the National Academy of Sciences 2020 Astronomy and Astrophysics Decadal Survey. The concept study phase is complete as of August 2019, ...

(lynx), and

Origins Space Telescope Origins Space Telescope (Origins) is a concept study for a far-infrared survey space telescope mission.National Academy of Sciences, whose independent

Decadal survey A decadal survey is a 10-year plan outlining scientific missions and goals created by the United States National Academies. It is a summary of input from scientists in the United States and beyond. Examples include: * Astronomy and Astrophysics ...

committee advises

on which mission should take top priority. If funded, LUVOIR would launch in approximately 2039 using a heavy launch vehicle, and it would be placed in an orbit around the Sun–Earth Lagrange 2.

Mission

LUVOIR's main goals are to investigate exoplanets, cosmic origins, and the

. LUVOIR would be able to analyze the structure and composition of exoplanet atmospheres and surfaces. It could also detect biosignatures arising from life in the atmosphere of a distant exoplanet. Atmospheric biosignatures of interest include , CO,

molecular oxygen There are several known allotropes of oxygen. The most familiar is molecular oxygen (O2), present at significant levels in Earth's atmosphere and also known as dioxygen or triplet oxygen. Another is the highly reactive ozone (O3). Others are: * ...

(),

ozone Ozone (), or trioxygen, is an inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , breaking down in the lo ...

(),

water Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...

(), and

methane Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Ea ...

(). LUVOIR's multi-wavelength capability would also provide key information to help understand how a host star's UV radiation regulates the atmospheric

photochemistry Photochemistry is the branch of chemistry concerned with the chemical effects of light. Generally, this term is used to describe a chemical reaction caused by absorption of ultraviolet (wavelength from 100 to 400 nm), visible light (400– ...

habitable planets Planetary habitability is the measure of a planet's or a natural satellite's potential to develop and maintain environments hospitable to life. Life may be generated directly on a planet or satellite endogenously or be transferred to it from a ...

. LUVOIR will also observe large numbers of exoplanets spanning a wide range of characteristics (mass, host star type, age, etc.), with the goal of placing the

in a broader context of planetary systems. Over its five-year primary mission, LUVOIR-A is expected to identify and study 54 potentially habitable exoplanets, while LUVOIR-B is expected to identify 28. The scope of astrophysics investigations include explorations of cosmic structure in the far reaches of space and time, formation and evolution of galaxies, and the birth of stars and planetary systems. In the area of

studies, LUVOIR can provide up to about 25 km imaging resolution in visible light at Jupiter, permitting detailed monitoring of atmospheric dynamics in

Jupiter 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 t ...

, Saturn,

Uranus Uranus is the seventh planet from the Sun. Its name is a reference to the Greek god of the sky, Uranus ( Caelus), who, according to Greek mythology, was the great-grandfather of Ares (Mars), grandfather of Zeus (Jupiter) and father of ...

, and Neptune over long timescales. Sensitive, high resolution imaging and spectroscopy of Solar System

comet A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena ...

s, asteroids,

moons A natural satellite is, in the most common usage, an astronomical body that orbits a planet, dwarf planet, or small Solar System body (or sometimes another natural satellite). Natural satellites are often colloquially referred to as ''moons'' ...

, and

Kuiper Belt objects The Kuiper belt () is a circumstellar disc in the outer Solar System, extending from the orbit of Neptune at 30 astronomical units (AU) to approximately 50 AU from the Sun. It is similar to the asteroid belt, but is far larger—20 times ...

that will not be visited by spacecraft in the foreseeable future can provide vital information on the processes that formed the Solar System ages ago. Furthermore, LUVOIR has an important role to play by studying plumes from the ocean moons of the outer Solar System, in particular Europa and

Enceladus Enceladus is the sixth-largest moon of Saturn (19th largest in the Solar System). It is about in diameter, about a tenth of that of Saturn's largest moon, Titan. Enceladus is mostly covered by fresh, clean ice, making it one of the most refle ...

, over long timescales.

Design

Comparison of LUVOIR-A and -B primary mirrors with Hubble and JWST

LUVOIR would be equipped with an internal

coronagraph A coronagraph is a telescopic attachment designed to block out the direct light from a star so that nearby objects – which otherwise would be hidden in the star's bright glare – can be resolved. Most coronagraphs are intended to view t ...

instrument, called ECLIPS for Extreme Coronagraph for LIving Planetary Systems, to enable direct observations of Earth-like exoplanets. An external starshade is also an option for the smaller LUVOIR design (LUVOIR-B). Other candidate science instruments studied are: High-Definition Imager (HDI), a wide-field near-UV, optical, and near-infrared

camera A camera is an optical instrument that can capture an image. Most cameras can capture 2D images, with some more advanced models being able to capture 3D images. At a basic level, most cameras consist of sealed boxes (the camera body), with a ...

; LUMOS, a LUVOIR Ultraviolet Multi-Object Spectrograph; and POLLUX, an ultraviolet

spectropolarimeter Polarimetry is the measurement and interpretation of the polarization of transverse waves, most notably electromagnetic waves, such as radio or light waves. Typically polarimetry is done on electromagnetic waves that have traveled through or ha ...

. POLLUX (high-resolution UV

) is being studied by a European consortium, with leadership and support from the

CNES The (CNES; French: ''Centre national d'études spatiales'') is the French government space agency (administratively, a "public administration with industrial and commercial purpose"). Its headquarters are located in central Paris and it is und ...

, France. The observatory can observe wavelengths of light from the far-ultraviolet to the

. To enable the extreme wavefront stability needed for coronagraphic observations of Earth-like exoplanets, the LUVOIR design incorporates three principles. First, vibrations and mechanical disturbances throughout the observatory are minimized. Second, the telescope and coronagraph both incorporate several layers of wavefront control through active optics. Third, the telescope is actively heated to a precise to control thermal disturbances. The LUVOIR technology development plan is supported with funding from NASA's Astrophysics Strategic Mission Concept Studies program, the Goddard Space Flight Center, the Marshall Space Flight Center, the

Jet Propulsion Laboratory The Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center in the City of La Cañada Flintridge, California, United States. Founded in the 1930s by Caltech researchers, JPL is owned by NASA an ...

and related programs at Northrop Grumman Aerospace Systems and

Ball Aerospace Ball Aerospace & Technologies Corp. is an American manufacturer of spacecraft, components and instruments for national defense, civil space and commercial space applications. The company is a wholly owned subsidiary of Ball Corporation (NYSE: BAL ...

LUVOIR-A

LUVOIR-A, previously known as the High Definition Space Telescope (HDST), would be composed of 36 mirror segments with an

aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An ...

of in diameter, offering images up to 24 times sharper than the

Hubble Space Telescope The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most vers ...

. LUVOIR-A would be large enough to find and study the dozens of Earthlike planets in our nearby neighborhood. It could resolve objects such as the nucleus of a small galaxy or a

gas cloud An interstellar cloud is generally an accumulation of gas, plasma, and dust in our and other galaxies. Put differently, an interstellar cloud is a denser-than-average region of the interstellar medium, the matter and radiation that exists in t ...

on the way to collapsing into a star and

planet A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a you ...

s. The first study for the HDST was published by the

Association of Universities for Research in Astronomy The Association of Universities for Research in Astronomy (AURA) is a consortium of universities and other institutions that operates astronomical observatories and telescopes. Founded October 10, 1957, with the encouragement of the National S ...

(AURA) on 6 July 2015. The case for HDST was made in a report entitled "From Cosmic Birth to Living Earths", on the future of

astronomy Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, g ...

commissioned by AURA, which runs the Hubble and other observatories on behalf of

and the

National Science Foundation The National Science Foundation (NSF) is an independent agency of the United States government that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National ...

. Ideas for the original HDST proposal included an internal

, a disk that blocks light from the central star, making a dim planet more visible, and a starshade that would float kilometers out in front of it to perform the same function. LUVOIR-A folds so it only needs an 8-metre wide payload fairing. Initial cost estimates are approximately US$10 billion, with lifetime cost estimates of $18 billion to $24 billion.

LUVOIR-B

LUVOIR-B, previously known as the Advanced Technology Large-Aperture Space Telescope (ATLAST), is an 8-metre architecture initially developed by the

Space Telescope Science Institute The Space Telescope Science Institute (STScI) is the science operations center for the Hubble Space Telescope (HST), science operations and mission operations center for the James Webb Space Telescope (JWST), and science operations center for the ...

, the science operations center for the

(HST) and the James Webb Space Telescope (JWST). While smaller than LUVOIR-A, it is being designed to produce an angular resolution that is 5–10 times better than the JWST, and a sensitivity limit that is up to 2,000 times better than HST. The LUVOIR Study Team expects that the telescope would be able to be serviced – similar to HST – either by an uncrewed spacecraft or by astronauts via Orion or Starship. Instruments such as cameras could potentially be replaced and returned to Earth for analysis of their components and future upgrades. The original

backronym A backronym is an acronym formed from an already existing word by expanding its letters into the words of a phrase. Backronyms may be invented with either serious or humorous intent, or they may be a type of false etymology or folk etymology. The ...

used for the initial mission concept, "ATLAST", was a pun referring to the time taken to decide on a successor for HST. ATLAST itself had three different proposed architectures – an monolithic mirror telescope, a segmented mirror telescope, and a segmented mirror telescope. The current LUVOIR-B architecture adopts JWST design heritage, essentially being an incrementally larger variant of the JWST, which has a 6.5 m segmented main mirror. Running on

solar power Solar power is the conversion of energy from sunlight into electricity, either directly using photovoltaics (PV) or indirectly using concentrated solar power. Photovoltaic cells convert light into an electric current using the photovolta ...

, it would use an internal

or an external occulter which can characterize the atmosphere and surface of an Earth-sized exoplanet in the

habitable zone In astronomy and astrobiology, the circumstellar habitable zone (CHZ), or simply the habitable zone, is the range of orbits around a star within which a planetary surface can support liquid water given sufficient atmospheric pressure.J. F. Kast ...

of long-lived stars at distances up to , including its rotation rate, climate, and habitability. The telescope would also allow researchers to glean information on the nature of the dominant surface features, changes in cloud cover and climate, and, potentially, seasonal variations in surface vegetation. LUVOIR-B was designed to launch on a heavy-lift rocket with an industry-standard diameter launch fairing. Lifetime cost estimates range from $12 billion to $18 billion.

References

External links

Large Ultraviolet Optical Infrared Telescope
project website
Large UV/Optical/IR Surveyor
at the Goddard Space Flight Center
Advanced Technology Large-Aperture Space Telescope
at the Goddard Space Flight Center
Advanced Technology Large-Aperture Space Telescope
at

STScI The Space Telescope Science Institute (STScI) is the science operations center for the Hubble Space Telescope (HST), science operations and mission operations center for the James Webb Space Telescope (JWST), and science operations center for the ...

High Definition Space Telescope
at AURA {{Exoplanet search projects Exoplanet search projects Proposed NASA space probes Proposed satellites Space telescopes Spacecraft using halo orbits Ultraviolet telescopes Artificial satellites at Earth-Sun Lagrange points