Aditya-L1: Difference between revisions

{{EngvarB|date=June 2019}}

| name = Aditya-L1

 

<!--image of the spacecraft/mission-->| image = Aditya-L1_spacecraft.jpg

| image_caption = Aditya-L1 in deployed configuration (credit:ISRO)

| image_size = <!--Basic details-->

| mission_type = Solar observation

| operator = [[Indian Space Research Organisation|ISRO]]

| COSPAR_ID =  

| SATCAT =  

| mission_duration = 5 years (planned) <ref name="CurrSci_113_04"/>

| spacecraft_bus = I-1K {{Citation needed|date=August 2017}}

 

<!--Spacecraft properties-->| manufacturer = [[Indian Space Research Organisation|ISRO]]{{\}}[[IUCAA]]{{\}}[[Indian Institute of Astrophysics|IIA]]

| launch_mass = {{convert|1500|kg|lb}} <ref name="CurrSci_113_04">{{cite journal|last1=Somasundaram|first1=Seetha|last2=Megala|first2=S.|title=Aditya-L1 mission|journal=Current Science|date=25 August 2017|volume=113|issue=4|pages=610|doi=10.18520/cs/v113/i04/610-612|url=http://www.currentscience.ac.in/Volumes/113/04/0610.pdf|access-date=25 August 2017}}</ref>

| payload_mass = {{convert|244|kg|lb|abbr=on}} (approx.) <ref name="CurrSci_113_04"/>

| power = <!--Launch details-->

| launch_date = January 2022<ref name="Somanath-20200803" />

| launch_rocket = [[Polar Satellite Launch Vehicle|PSLV-XL]] C56<ref name="CurrSci_113_04"/><ref name="Hindu1" /><ref name="ls-100321"/>

| launch_site = [[Satish Dhawan Space Centre]]

 

<!--orbit parameters-->| orbit_reference = [[Lagrangian point#L1|Sun–Earth L₁]]

| orbit_regime = [[Halo orbit]]

| orbit_periapsis =  

| orbit_apoapsis =  

| orbit_inclination =  

| orbit_period = 177.86 days<ref name="COPUOS_62">{{cite web |last1=Sreekumar |first1=P. |title=Indian Space Science & Exploration : Global Perspective |url=http://www.unoosa.org/documents/pdf/copuos/2019/copuos2019tech32E.pdf |website=UNOOSA |access-date=30 June 2019 |page=8 |date=19 June 2019}}</ref>

| apsis = <!--Instrument List-->

| instruments_list = {{Infobox spaceflight/Instruments

   | acronym1 = VELC | name1 = Visible Emission Line [[Coronagraph]]

   | acronym2 = SUIT | name2 = Solar Ultraviolet Imaging Telescope

   | acronym3 = ASPEX | name3 = Aditya Solar wind Particle Experiment

   | acronym4 = PAPA | name4 = Plasma Analyser Package for Aditya

   | acronym7 = [[Magnetometer]] | name7 = &nbsp;

==History==

Aditya was conceptualised in January 2008 by the Advisory Committee for Space Research. It was initially envisaged as a small 400&nbsp;kg, low-Earth orbiting satellite with a [[coronagraph]] to study the [[solar corona]]. An experimental budget of 3 Crore [[Indian rupee|INR was]] allocated for the financial year 2016–2017.<ref name="2016-17_budget">{{cite press release | url=http://indiabudget.nic.in/ub2016-17/eb/sbe84.pdf | title=Notes on Demands for Grants, 2016-2017 | publisher=Department of Space | access-date=9 September 2016 | archive-url=https://web.archive.org/web/20160917064145/http://indiabudget.nic.in/ub2016-17/eb/sbe84.pdf | archive-date=17 September 2016 | url-status=dead }}</ref><ref>{{Cite news| url=http://www.thehindu.com/todays-paper/tp-national/aditya-gets-ready-to-gaze-at-the-sun/article8212387.ece| title=Aditya gets ready to gaze at the sun |work=The Hindu| access-date=2017-08-25|language=en}}</ref><ref>{{Cite news |url=http://www.thehindu.com/todays-paper/ISRO-planning-to-launch-satellite-to-study-the-sun/article15143000.ece| title=ISRO planning to launch satellite to study the sun| last=Gandhi| first=Divya|date=13 January 2008 |work=The Hindu| access-date=26 August 2017}}</ref> The scope of the mission has since been expanded and it is now planned to be a comprehensive solar and space environment observatory to be placed at the [[Lagrangian point]] L1,<ref>{{cite news| url=http://www.thehindu.com/opinion/the-sun-shines-on-indias-aditya/article7878625.ece |title=The sun shines on India's Aditya| last=Desikan| first=Shubashree| date=15 November 2015|work=The Hindu |access-date=12 August 2018}}</ref> so the mission was renamed "Aditya-L1". {{As of|2019|7|df=}}, the mission has an allocated cost of ₹378.53 [[crore]] excluding launch costs.<ref>{{Cite web| url=http://164.100.24.220/loksabhaquestions/annex/171/AU1972.pdf|title=Lok Sabha Unstarred Question No.1972| date=3 July 2019 |website=LokSabha}}</ref>

[[File:Lagrange-better.png|thumb|300x300px|[[Lagrangian point]]s in the Sun–Earth system (not to scale) – a small object at any one of the five points will hold its relative position.]]

The Aditya-L1 mission will be inserted in a [[halo orbit]] around the [[Lagrangian point|L1 point]], which is about 1.5 million km from Earth. The 1,500&nbsp;kg  satellite carries seven science payloads with diverse objectives, including but not limited to, the [[Coronal heating problem|coronal heating]], [[solar wind]] acceleration, coronal magnetometry, origin and monitoring of near-UV solar radiation (which drives Earth's upper atmospheric dynamics and global climate), coupling of the solar photosphere to chromosphere and corona, in-situ characterisations of the space environment around Earth by measuring energetic particle fluxes and magnetic fields of the solar wind and [[Solar storm|solar magnetic storms]] that have adverse effects on space and ground-based technologies.<ref name="CurrSci_113_04"/>

Aditya-L1 will be able to provide observations of Sun's [[photosphere]], [[chromosphere]] and [[solar corona|corona]].  In addition, an instrument will study the [[solar energetic particles]]' flux reaching the L1 orbit, while a [[magnetometer]] payload will measure the variation in [[Sun#Magnetic field|magnetic field]] strength at the halo orbit around L1. These payloads have to be placed outside the interference from the Earth's magnetic field and hence could not have been useful in the low Earth orbit as proposed on the original Aditya mission concept.<ref>{{Cite web| url=https://www.isro.gov.in/aditya-l1-first-indian-mission-to-study-sun| title=Aditya - L1 First Indian mission to study the Sun - ISRO| website=www.isro.gov.in|access-date=2019-06-19}}</ref>

One of the major unsolved issues in the field of [[solar physics]] is that the upper atmosphere of the Sun is {{cvt|1000000|K|C F}} hot whereas the lower atmosphere is just {{cvt|6000|K|C F}}. In addition, it is not understood how exactly the Sun's radiation affects the dynamics of the Earth's atmosphere on shorter as well as on longer time scale. The mission will obtain near simultaneous images of the different layers of the Sun's atmosphere, which reveal the ways in which the energy may be channeled and transferred from one layer to another. Thus the Aditya-L1 mission will enable a comprehensive understanding of the dynamical processes of the Sun and address some of the outstanding problems in solar physics and [[heliophysics]].

The satellite is planned to launched onboard PSLV-XL flight C56 in late 2021 or early 2022.<ref name="ls-100321">{{cite web|url=http://164.100.24.220/loksabhaquestions/annex/175/AU2587.pdf|title=Question -MISSIONS OF ISRO Loksabha|date=10 March 2021|publisher=Lok Sabha}}</ref>

==Payloads==

* '''Visible Emission Line Coronagraph (VELC)''':  The [[coronagraph]] creates an artificial total solar eclipse in space by blocking the sunlight by an occultor. This telescope will have capabilities of [[spectral imaging]] of the corona in visible and infra-red wavelengths. The objectives are to study the diagnostic parameters of solar corona and dynamics and origin of [[coronal mass ejection]]s (using three visible and one infra-red channels); magnetic field measurements of the solar corona down to tens of [[Gauss (unit)|Gauss]]. Additional objectives are to determine why the solar atmosphere is so hot, and how the changes in the Sun can affect [[space weather]] and Earth's climate. The VELC payload weighs nearly 170&nbsp;kg.<ref name=":0">{{Cite news| url=http://www.thehindu.com/sci-tech/science/here-comes-the-sun-watcher-indias-aditya-l1/article20942099.ece |title=Here comes the sun watcher, India's Aditya-L1| last=Desikan| first=Shubashree| date=26 November 2017|work=TheHindu|access-date=26 November 2017}}</ref>

* '''Solar Ultraviolet Imaging Telescope (SUIT)''': SUIT will observe the Sun between 200-400&nbsp;nm wavelength range and it will provide full disk images of different layers of the solar atmosphere by making use of 11 filters. The Sun has never been observed from space in this wavelength range. The spacecraft being at the first Lagrangian point, SUIT shall be observing the Sun continuously without interruption. The instrument is being developed under the leadership of A. N. Ramaprakash and Durgesh Tripathi at the [[Inter-University Centre for Astronomy and Astrophysics]] (IUCAA) at Pune, in collaboration with ISRO and other institutes. The SUIT payload weighs nearly 35&nbsp;kg.<ref name=":0" />

* '''Aditya Solar wind Particle Experiment (ASPEX)<ref>{{cite journal

| pages      = 42–55

}}</ref>''': To study the variation and properties of the [[solar wind]] as well as its distribution and spectral characteristics.

**PI Institute: [[Physical Research Laboratory]] (PRL).

**PI Institute: Space Physics Laboratory (SPL), [[Vikram Sarabhai Space Centre|VSSC]].

* '''Solar Low Energy X-ray Spectrometer (SoLEXS)''': To monitor the [[X-ray spectroscopy|X-ray flares]] for studying the enigmatic [[Coronal heating problem|coronal heating]] mechanism of the solar corona.

**PI Institute: [[ISRO Satellite centre]] (ISAC).

* '''High Energy L1 Orbiting X-ray Spectrometer (HEL1OS):''' To observe the dynamic events in the solar corona and provide an estimate of the energy used to accelerate the [[solar energetic particles]] during the eruptive events.

**PI Institutes: ISRO Satellite Centre (ISAC) and Udaipur Solar Observatory (USO), PRL.

}}</ref>''': To measure the magnitude and nature of the [[interplanetary magnetic field]].

==References==

{{reflist|30em}}

==External links==

*{{cite web |url=http://www.isro.gov.in/aditya-l1-first-indian-mission-to-study-sun |title=Aditya - L1 First Indian mission to study the Sun |publisher=[[Indian Space Research Organisation]] |access-date=1 June 2017 }}

[[Category:2022 in spaceflight]]

[[Category:2022 in India]]