Shukrayaan-1 () is a planned orbiter to

Venus Venus is the second planet from the Sun. It is sometimes called Earth's "sister" or "twin" planet as it is almost as large and has a similar composition. As an interior planet to Earth, Venus (like Mercury) appears in Earth's sky never fa ...

by the

Indian Space Research Organisation The Indian Space Research Organisation (ISRO; ) is the national space agency of India, headquartered in Bengaluru. It operates under the Department of Space (DOS) which is directly overseen by the Prime Minister of India, while the Chairman ...

(ISRO) to study the surface and

atmosphere of Venus The atmosphere of Venus is the layer of gases surrounding Venus. It is composed primarily of supercritical carbon dioxide and is much denser and hotter than that of Earth. The temperature at the surface is 740 K (467 °C, 872 ° ...

. Funds were released in 2017 to complete preliminary studies, and solicitations for instruments have been announced. The orbiter, depending on its final configuration, would have a science payload capability of approximately with 500 W available power. The initial elliptical orbit around Venus is expected to have at periapsis and at apoapsis.

Overview

The three broad research areas of interest for this mission include surface/subsurface

stratigraphy Stratigraphy is a branch of geology concerned with the study of rock (geology), rock layers (Stratum, strata) and layering (stratification). It is primarily used in the study of sedimentary rock, sedimentary and layered volcanic rocks. Stratigrap ...

and re-surfacing processes; second: study the atmospheric chemistry, dynamics and compositional variations, and third: study of

solar irradiance Solar irradiance is the power per unit area (surface power density) received from the Sun in the form of electromagnetic radiation in the wavelength range of the measuring instrument. Solar irradiance is measured in watts per square metre (W/ ...

and

solar wind The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona. This plasma mostly consists of electrons, protons and alpha particles with kinetic energy between . The composition of the sola ...

interaction with Venus ionosphere while studying the structure, composition and dynamics of the atmosphere.

Status

Based on the success of

Chandrayaan The Chandrayaan programme (), also known as the Indian Lunar Exploration Programme is an ongoing series of outer space missions by the Indian Space Research Organisation (ISRO). The programme incorporates lunar orbiter, impactor, soft lander an ...

and the

Mangalyaan The Mars Orbiter Mission (MOM), also called ''Mangalyaan'', was a space probe orbiting Mars since 24 September 2014. It was launched on 5 November 2013 by the Indian Space Research Organisation (ISRO). It was India's first interplanetary missio ...

, ISRO has been studying the feasibility of future interplanetary missions to Mars and Venus, the closest planetary neighbours to Earth. The mission concept to Venus was first presented at a Tirupati space meet in 2012.India planning Venus mission.
Srinivas Laxman, ''The Times of India''. 17 February 2012. The

Government of India The Government of India (ISO: ; often abbreviated as GoI), known as the Union Government or Central Government but often simply as the Centre, is the national government of the Republic of India, a federal democracy located in South Asia, c ...

, in its budget for 2017–18 gave the

Department of Space The Department of Space is an Indian government department responsible for administration of the Indian space program. It manages several agencies and institutes related to space exploration and space technologies. The Indian space program und ...

a 23% increase. Under the space sciences section, the budget mentions provisions "for Mars Orbiter Mission II and Mission to Venus", and following the 2017–18 request for grants, it was authorized to complete preliminary studies. From 2016 to 2017, ISRO collaborated with JAXA to study the Venus atmosphere using signals from the

Akatsuki may refer to: * Akatsuki (spacecraft), an uncrewed Venus orbiter * , any of three classes of destroyers of the Imperial Japanese Navy * , any of three destroyers of the Imperial Japanese Navy * ''Akatsuki'' (train), operated between Kyoto and Na ...

in a radio occultation experiment. On 19 April 2017, ISRO made an 'Announcement of Opportunity' (AO) seeking science payload proposals from Indian academia based on broad mission specifications. On 6 November 2018, ISRO made another 'Announcement of Opportunity' inviting payload proposals from the international scientific community. The available science payload capacity was revised to 100 kg from 175 kg mentioned in the first AO. The space agencies of India (ISRO) and France (

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 ...

) were holding in 2018 discussions to collaborate on this mission and jointly develop autonomous navigation and

aerobraking Aerobraking is a spaceflight maneuver that reduces the high point of an elliptical orbit (apoapsis) by flying the vehicle through the atmosphere at the low point of the orbit (periapsis). The resulting drag slows the spacecraft. Aerobraking is ...

technologies. In addition, French astrophysicist

Jacques Blamont Jacques Émile Blamont (; 13 October 1926 – 13 April 2020) was a French astrophysicist, author and the founder scientific and technical director of National Centre for Space Studies (CNES-Centre national d'études spatiales), known to ha ...

, with his experience from the

Vega program The Vega program (Cyrillic: ВеГа) was a series of Venus missions that also took advantage of the appearance of comet 1P/Halley in 1986. ''Vega 1'' and ''Vega 2'' were uncrewed spacecraft launched in a cooperative effort among the Soviet U ...

, expressed his interest to U R Rao to use inflated balloons to help study the Venusian atmosphere. Just like during the Vega missions, these instrumented balloons could be deployed from an orbiter and take prolonged observations while floating in the relatively mild upper atmosphere of the planet. ISRO agreed to consider the proposal to use a balloon probe carrying payload to study the Venusian atmosphere at altitude. As of late 2018, the Venus mission is in the configuration study phase and ISRO has not sought the Indian government's full approval.

Somak Raychaudhury Somak Raychaudhury ( bn, সোমক রায়চৌধুরী) is an Indian astrophysicist. He is the Director of the Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pune. He is on leave from Presidency University, Kol ...

, the director of

IUCAA The Inter-University Centre for Astronomy and Astrophysics (IUCAA) is an autonomous institution set up by the University Grants Commission of India to promote nucleation and growth of active groups in astronomy and astrophysics in Indian univer ...

, stated in 2019 that a drone-like probe was being considered to be a part of mission. In an update provided to NASA's Decadal Planetary Science Committee, ISRO scientist T Maria Antonita, said that the launch is expected to take place in December 2024. She said that there is also a backup date in 2026. As of November 2020, ISRO has shortlisted 20 international proposals that include collaboration with Russia, France, Sweden and Germany.

Swedish Institute of Space Physics The Swedish Institute of Space Physics ( sv, Institutet för rymdfysik, IRF) is a Swedish government agency. The institute's primary task is to carry out basic research, education and associated observatory activities in space physics, space tech ...

is engaged with ISRO for Shukrayaan-1 mission. In May 2022, ISRO chairman

S. Somanath Sreedhara Panicker Somanath (born July 1963) is an Indian Aerospace engineering, aerospace engineer serving as the Chairman of the Indian Space Research Organisation, chairman of the Indian Space Research Organisation. Somanath also served as ...

stated that the mission is planned for launch in December 2024, with an alternate launch window in 2031.

Science payload

The science payload would have a mass of and would consist of instruments from India and other countries. , 16 Indian and 7 international payloads have been shortlisted.Alt URL
/ref> Some of them will be selected.

Indian instruments

* Venus L&S-Band SAR * VARTISS (HF radar) * VSEAM (Surface Emissivity) * VTC (Thermal Camera) * VCMC (Cloud Monitoring) * LIVE (Lightning Sensor) * VASP (Spectro Polarimeter) * SPAV (Solar occultation photometry) * NAVA (

Airglow Airglow (also called nightglow) is a faint emission of light by a planetary atmosphere. In the case of Earth's atmosphere, this optical phenomenon causes the night sky never to be completely dark, even after the effects of starlight and diff ...

imager) * RAVI (RO Experiment)* * ETA (Electron Temperature Analyser) * RPA (Retarding Potential Analyser) *

Mass Spectrometer Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used ...

* VISWAS (Plasma Analyser)* * Venus Radiation environment monitor (VeRad) * Venus Solar Soft x-ray Spectrometer (VS3) * VIPER (Plasma Wave Detector) * VODEX (Dust experiment) :* RAVI and VISWAS are being proposed as collaboration with Germany and Sweden.

International instruments

*Terahertz devices to generate powerful radar pulses. Proposed by NASA. Two Russian payloads by the

Russian Space Research Institute The Russian Space Research Institute (russian: Институт космических исследований Российской академии наук, Space Research Institute of the Russian Academy of Sciences, SRI RAS, Russian abbreviat ...

and

Moscow Institute of Physics and Technology Moscow Institute of Physics and Technology (MIPT; russian: Московский Физико-Технический институт, also known as PhysTech), is a public research university located in Moscow Oblast, Russia. It prepares speciali ...

have been shortlisted, both would study the

: * VIRAL (Venus InfraRed Atmospheric gases Linker) by Space research Institute, Moscow (after their collaboration with LATMOS, France ended) * IVOLGA: A laser heterodyne NIR spectrometer for studying of structure and dynamics of the Venusian mesosphere.

References