On 2 October 2022, it was reported that the orbiter had irrecoverably lost communications with Earth after entering a seven-hour eclipse period in April 2022 that it was not designed to survive.[29][30][31] The following day, ISRO released a statement that all attempts to revive MOM had failed and officially declared it dead, citing the loss of fuel and battery power to the probe's instruments.[32]
History
In November 2008, the first public acknowledgement of an uncrewed mission to Mars was announced by then-ISRO chairman
G. Madhavan Nair.[33] The MOM mission concept began with a feasibility study in 2010 by the
Indian Institute of Space Science and Technology after the launch of lunar satellite
Chandrayaan-1 in 2008. Prime Minister
Manmohan Singh approved the project on 3 August 2012,[34][35] after the
Indian Space Research Organisation completed ₹125 crore (US$16 million) of required studies for the orbiter.[36] The total project cost may be up to ₹454 crore (US$57 million).[14][37] The satellite costs ₹153 crore (US$19 million) and the rest of the budget has been attributed to ground stations and relay upgrades that will be used for other ISRO projects.[38]
The space agency had planned the launch on 28 October 2013 but was postponed to 5 November following the delay in ISRO's spacecraft tracking ships to take up pre-determined positions due to poor weather in the Pacific Ocean.[6] Launch opportunities for a fuel-saving
Hohmann transfer orbit occur every 26 months, in this case the next two would be in 2016 and 2018.[39]
Assembly of the PSLV-XL launch vehicle, designated C25, started on 5 August 2013.[40] The mounting of the five scientific instruments was completed at
Indian Space Research Organisation Satellite Centre,
Bengaluru, and the finished spacecraft was shipped to Sriharikota on 2 October 2013 for integration to the PSLV-XL launch vehicle.[40] The satellite's development was fast-tracked and completed in a record 15 months,[41] partly due to using reconfigured
Chandrayaan-2 orbiter bus.[42] Despite the
US federal government shutdown, NASA reaffirmed on 5 October 2013 it would provide communications and navigation support to the mission "with their
Deep Space Network facilities.".[43] During a meeting on 30 September 2014, NASA and ISRO officials signed an agreement to establish a pathway for future joint missions to explore Mars. One of the working group's objectives will be to explore potential coordinated observations and science analysis between the
MAVEN orbiter and MOM, as well as other current and future Mars missions.[44]
On 2 October 2022, it was reported that the orbiter had irrecoverably lost communications with Earth after entering long eclipse period in April 2022 that it was not designed to survive. At the time of communications loss it was unknown whether the probe had lost power or inadvertently realigned its Earth-facing antenna during automatic maneuvers.[29]
Team
Some of the scientists of isro and engineers involved in the mission include:[45]
S. K. Shivakumar was the Director at the ISRO Satellite Centre. He was also a Project Director for the
Indian Deep Space Network. Mars Orbiter Mission is the product of
ISRO Satellite Centre (ISAC). He spearheaded the task of conceptualization, design and realization of the unique spacecraft MOM. He ingeniously planned to realize the spacecraft in a record time of 15 months
Mylswamy Annadurai was the Programme Director and was in charge of budget management as well as direction for spacecraft configuration, schedule and resources.
Subbiah Arunan was the Project Director at the Mars Orbiter Mission.
B Jayakumar was an Associate Project Director at the PSLV programme which was responsible for testing the rocket systems.
S Ramakrishnan was the Director who helped in the development of the liquid propulsion system of the PSLV launcher.
P. Kunhikrishnan was the Project Director in the PSLV programme. He was also a Mission director of the PSLV-C25/Mars Orbiter Mission.
Moumita Dutta was the Project manager of the Mars Orbiter Mission.
Nandini Harinath was the Deputy Operations Director of Navigation.
Ritu Karidhal was the Deputy Operations Director of Navigation.
BS Kiran was the Associate Project Director of Flight Dynamics.
V Kesava Raju was the Mars Orbiter Mission Director.
V Koteswara Rao was the ISRO scientific secretary.
Chandradathan was the Director of the Liquid Propulsion System.
A. S. Kiran Kumar was the Director of the Satellite Application Centre, who later went on to be the
Chairman ISRO after this, when the team studied the Mard
M. Y. S. Prasad is the Director at Satish Dhawan Space Centre. He was also the chairman of the Launch Authorisation Board.
MS Pannirselvam was the Chief General Manager at the Sriharikota Rocket port and was tasked to maintain launch schedules.
Cost
The total cost of the mission was approximately ₹450
Crore (US$73 million),[46][47] making it the least-expensive Mars mission to date.[48] The low cost of the mission was ascribed by ISRO chairman
K. Radhakrishnan to various factors, including a "modular approach", few ground tests and long working days (18 to 20 hours) for scientists.[49]BBC's Jonathan Amos specified lower worker costs, home-grown technologies, simpler design, and a significantly less complicated payload than NASA's
MAVEN.[27]
Mission objectives
The primary objective of the mission is to develop the technologies required for designing, planning, management and operations of an
interplanetary mission.[26] The secondary objective is to explore Mars' surface features,
morphology,
mineralogy and
Martian atmosphere using indigenous scientific instruments.[50]
The main objectives are to develop the technologies required for designing, planning, management and operations of an interplanetary mission comprising the following major tasks:[51]: 42
Orbit manoeuvres to transfer the spacecraft from Earth-centred orbit to heliocentric trajectory and finally, capture into Martian orbit
Development of force models and algorithms for orbit and
attitude (orientation) computations and analysis
Navigation in all phases
Maintain the spacecraft in all phases of the mission
Meeting power, communications, thermal and payload operation requirements
Incorporate autonomous features to handle contingency situations
Scientific objectives
The scientific objectives deal with the following major aspects:[51]: 43
Exploration of Mars surface features by studying the morphology, topography and mineralogy
Study the constituents of Martian atmosphere including
methane and CO2 using remote sensing techniques
Study the dynamics of the upper atmosphere of Mars, effects of
solar wind and radiation and the escape of volatiles to outer space
The mission would also provide multiple opportunities to observe the Martian moon
Phobos and also offer an opportunity to identify and re-estimate the orbits of asteroids seen during the Martian Transfer Trajectory.[51]: 43 The spacecraft also provided the first views ever of the far side of Martian Moon
Deimos.
Studies
In May–June 2015 Indian scientists got an opportunity to study the Solar Corona during the Mars conjunction when earth and Mars are on the opposite sides of the sun. During this period the S band waves emitted by MOM were transmitted through the Solar Corona that extends millions of kms into space. This event helped scientists study the Solar surface and regions where temperature changed abruptly.[52]
Spacecraft design
Mass: The lift-off mass was 1,337.2 kg (2,948 lb), including 852 kg (1,878 lb) of propellant.[3]
Bus: The spacecraft's
bus is a modified
I-1 K structure and propulsion hardware configuration, similar to
Chandrayaan-1, India's lunar orbiter that operated from 2008 to 2009, with specific improvements and upgrades needed for a Mars mission.[50] The satellite structure is constructed of an aluminium and composite fibre reinforced plastic (
CFRP) sandwich construction.[53]
Power: Electric power is generated by three
solar array panels of 1.8 m × 1.4 m (5 ft 11 in × 4 ft 7 in) each (7.56 m2 (81.4 sq ft) total), for a maximum of 840 watts of power generation in Mars orbit. Electricity is stored in a 36
AhLithium-ion battery.[2][54]
Propulsion: A liquid fuel engine with a thrust of 440
newtons (99
lbf) is used for orbit raising and insertion into Mars orbit. The orbiter also has eight 22-newton (4.9 lbf) thrusters for
attitude control (orientation).[55] Its propellant mass at launch was 852 kg (1,878 lb).[2]
Attitude and Orbit Control System: Maneuvering system that includes electronics with a
MAR31750 processor, two star sensors, a solar panel Sun sensor, a coarse analog Sun sensor, four reaction wheels, and the primary propulsion system.[2][56]
Antennae: Low gain antenna, mid gain antenna, and high gain antenna.[2]
The 15 kg (33 lb) scientific payload consists of five instruments:[58][59][60]
Atmospheric studies:
Lyman-Alpha Photometer (LAP) – a
photometer that measures the relative abundance of
deuterium and
hydrogen from
Lyman-alpha emissions in the upper atmosphere. Measuring the deuterium/hydrogen ratio will allow an estimation of the amount of water loss to
outer space. The nominal plan to operate LAP is between the ranges of approximately 3,000 km (1,900 mi) before and after Mars periapsis. Minimum observation duration for achieving LAP's science goals is 60 minutes per orbit during normal range of operation. The objectives of this instrument are as follows:[51]: 56, 57
Methane Sensor for Mars (MSM) – was meant to measure
methane in the atmosphere of Mars, if any, and map its sources with an accuracy of few 10s parts-per-billion (ppb).[58] After entering Mars orbit it was determined that the instrument, although in good working condition, had a design flaw and it was incapable of distinguishing methane on Mars. The instrument can accurately map Mars albedo at 1.65 um.[57][61]
MSM Design Flaw. The MSM sensor was expected to measure methane in the Mars atmosphere; methane on Earth is often associated with life. However, after it entered orbit, it was reported that there was an issue with how it collected and processed data. The spectrometer could measure intensity of different spectral bands, [such as methane] but instead of sending back the spectra, it sent back the sum of the sampled spectra and also the gaps between the sampled lines. The difference was supposed to be the methane signal, but since other spectra such as carbon dioxide could have varying intensities, it was not possible to determine the actual methane intensity. The device was repurposed as an albedo mapper.[62]
Particle environment studies:
Mars Exospheric Neutral Composition Analyser (MENCA) – is a
quadrupole mass analyser capable of analysing the neutral composition of particles in the range of 1–300 amu (atomic mass unit) with unit mass resolution. The heritage of this payload is from Chandra's Altitudinal Composition Explorer (CHACE) payload aboard the Moon Impact Probe (MIP) in
Chandrayaan-1 mission. MENCA is planned to perform five observations per orbit with one hour per observation.[51]: 58
Surface imaging studies:
Thermal Infrared Imaging Spectrometer (TIS) – TIS measures the thermal emission and can be operated during both day and night. It would map surface composition and mineralogy of Mars and also monitor atmospheric CO2 and turbidity (required for the correction of MSM data). Temperature and emissivity are the two basic physical parameters estimated from thermal emission measurement. Many minerals and soil types have characteristic spectra in TIR region. TIS can map surface composition and mineralogy of Mars.[51]: 59
Mars Colour Camera (MCC) – This tricolour camera gives images and information about the surface features and composition of Martian surface. It is useful to monitor the dynamic events and weather of Mars like dust storms/atmospheric turbidity. MCC will also be used for probing the two satellites of Mars,
Phobos and
Deimos. MCC would provide context information for other science payloads. MCC images are to be acquired whenever MSM and TIS data is acquired. Seven Apoareion Imaging of the entire disc and multiple Periareion images of 540 km × 540 km (340 mi × 340 mi) are planned in every orbit.[51]: 58
Communications are handled by two 230-watt
TWTAs and two
coherent transponders. The antenna array consists of a
low-gain antenna, a medium-gain antenna and a
high-gain antenna. The high-gain antenna system is based on a single 2.2-metre (7 ft 3 in) reflector illuminated by a feed at
S-band. It is used to transmit and receive the telemetry, tracking, commanding and data to and from the
Indian Deep Space Network.[2]
En route to Mars – The probe travelled a distance of 780,000,000 kilometres (480,000,000 mi) in a
Hohmann transfer orbit[39] around the Sun to reach Mars.[65] This phase plan included up to four trajectory corrections if needed.
ISRO originally intended to launch MOM with its
Geosynchronous Satellite Launch Vehicle (GSLV),[87] but the GSLV failed twice in 2010 and still had issues with its
cryogenic engine.[88] Waiting for the new batch of rockets would have delayed the MOM for at least three years,[89] so ISRO opted to switch to the less-powerful
Polar Satellite Launch Vehicle (PSLV). Since it was not powerful enough to place MOM on a direct-to-Mars trajectory, the spacecraft was launched into a highly elliptical Earth orbit and used its own thrusters over multiple perigee burns (to take advantage of the
Oberth effect) to place itself on a
trans-Mars trajectory.[87]
On 19 October 2013, ISRO chairman
K. Radhakrishnan announced that the launch had to be postponed by a week for 5 November 2013 due to a delay of a crucial telemetry ship reaching
Fiji. The launch was rescheduled.[6] ISRO's PSLV-XL placed the satellite into Earth orbit at 09:50 UTC on 5 November 2013,[36] with a perigee of 264.1 km (164.1 mi), an apogee of 23,903.6 km (14,853.0 mi), and inclination of 19.20 degrees,[68] with both the antenna and all three sections of the solar panel arrays deployed.[90] During the first three orbit raising operations, ISRO progressively tested the spacecraft systems.[74]
The orbiter's dry mass is 482.5 kg (1,064 lb) and it carried 852 kg (1,878 lb) of fuel at launch.[3][91][92] Its main engine, a derivative of the system used on India's communications satellites, uses the bipropellant combination
monomethylhydrazine and
dinitrogen tetroxide to achieve the thrust necessary for
escape velocity from Earth. It was also used to slow down the probe for Mars orbit insertion and, subsequently, for orbit corrections.[93]
ITRF1993 frame, plate motion epoch 01-Jan-2003 00:00 UTC
Orbit raising manoeuvres
Several orbit raising operations were conducted from the
Spacecraft Control Centre (SCC) at the
ISRO Telemetry, Tracking and Command Network (ISTRAC) at Peenya, Bengaluru on 6, 7, 8, 10, 12 and 16 November by using the spacecraft's on-board propulsion system and a series of perigee burns. The first three of the five planned orbit raising manoeuvres were completed with nominal results, while the fourth was only partially successful. However, a subsequent supplementary manoeuvre raised the orbit to the intended altitude aimed for in the original fourth manoeuvre. A total of six burns were completed while the spacecraft remained in Earth orbit, with a seventh burn conducted on 30 November to insert MOM into a
heliocentricorbit for its transit to Mars.[95]
The first orbit-raising manoeuvre was performed on 6 November 2013 at 19:47 UTC when the spacecraft's 440-newton (99 lbf)
liquid engine was fired for 416 seconds. With this engine firing, the spacecraft's
apogee was raised to 28,825 km (17,911 mi), with a
perigee of 252 km (157 mi).[69]
The second orbit raising manoeuvre was performed on 7 November 2013 at 20:48 UTC, with a burn time of 570.6 seconds resulting in an apogee of 40,186 km (24,970 mi).[70][71]
The third orbit raising manoeuvre was performed on 8 November 2013 at 20:40 UTC, with a burn time of 707 seconds, resulting in an apogee of 71,636 km (44,513 mi).[70][72]
The fourth orbit raising manoeuvre, starting at 20:36 UTC on 10 November 2013, imparted a
delta-v of 35 m/s (110 ft/s) to the spacecraft instead of the planned 135 m/s (440 ft/s) as a result of underburn by the motor.[73][96] Because of this, the apogee was boosted to 78,276 km (48,638 mi) instead of the planned 100,000 km (62,000 mi).[73] When testing the redundancies built-in for the propulsion system, the flow to the liquid engine stopped, with consequent reduction in incremental velocity. During the fourth orbit burn, the primary and redundant coils of the solenoid flow control valve of 440 newton liquid engine and logic for thrust augmentation by the attitude control thrusters were being tested. When both primary and redundant coils were energised together during the planned modes, the flow to the liquid engine stopped. Operating both the coils simultaneously is not possible for future operations, however they could be operated independently of each other, in sequence.[74]
As a result of the fourth planned burn coming up short, an additional unscheduled burn was performed on 12 November 2013 that increased the apogee to 118,642 km (73,721 mi),[70][74] a slightly higher altitude than originally intended in the fourth manoeuvre.[70][97] The apogee was raised to 192,874 km (119,846 mi) on 15 November 2013, 19:57 UTC in the final orbit raising manoeuvre.[70][97]
On 30 November 2013 at 19:19 UTC, a 23-minute engine firing initiated the
transfer of MOM away from Earth orbit and on
heliocentric orbit toward Mars.[25] The probe travelled a distance of 780,000,000 kilometres (480,000,000 mi) to reach Mars.[98]
Trajectory correction maneuvers
Four trajectory corrections were originally planned, but only three were carried out.[77] The first trajectory correction manoeuvre (TCM) was carried out on 11 December 2013 at 01:00 UTC by firing the 22-newton (4.9 lbf) thrusters for a duration of 40.5 seconds.[70][99] After this event, MOM was following the designed trajectory so closely that the trajectory correction manoeuvre planned in April 2014 was not required. The second trajectory correction manoeuvre was performed on 11 June 2014 at 11:00 UTC by firing the spacecraft's 22 newton thrusters for 16 seconds.[100] The third planned trajectory correction manoeuvre was postponed, due to the orbiter's trajectory closely matching the planned trajectory.[101] The third trajectory correction was also a deceleration test 3.9 seconds long on 22 September 2014.[86]
Mars orbit insertion
The plan was for an insertion into
Mars orbit on 24 September 2014,[10][102] approximately 2 days after the arrival of NASA's
MAVEN orbiter.[103] The 440-newton liquid apogee motor was test fired on 22 September at 09:00 UTC for 3.968 seconds, about 41 hours before actual orbit insertion.[102][104][105]
Date
Time (UTC)
Event
23 September 2014
10:47:32
Satellite communication switched to medium gain antenna
After these events, the spacecraft performed a reverse manoeuvre to reorient from its deceleration burn and entered Martian orbit.[9][106][4]
Status
The orbit insertion put MOM in a highly elliptical orbit around Mars, as planned, with a period of 72 hours 51 minutes 51 seconds, a
periapsis of 421.7 km (262.0 mi) and
apoapsis of 76,993.6 km (47,841.6 mi).[9] At the end of the orbit insertion, MOM was left with 40 kg (88 lb) of fuel on board, more than the 20 kg (44 lb) necessary for a six-month mission.[107]
On 28 September 2014, MOM controllers published the spacecraft's first global view of Mars. The image was captured by the Mars Colour Camera (MCC).[108]
On 7 October 2014, the ISRO altered MOM's orbit so as to move it behind Mars for
comet Siding Spring's flyby of the planet on 19 October 2014. The spacecraft consumed 1.9 kg (4 lb) of fuel for the manoeuvre. As a result, MOM's apoapsis was reduced to 72,000 km (45,000 mi).[109] After the comet passed by Mars, ISRO reported that MOM remained healthy.[110]
On 4 March 2015, the ISRO reported that the MSM instrument was functioning normally and are studying Mars'
albedo, the reflectivity of the planet's surface. The Mars Colour Camera was also returning new images of the Martian surface.[111][112]
On 24 March 2015, MOM completed its initial six-month mission in orbit around Mars. ISRO extended the mission by an additional six months; the spacecraft has 37 kg (82 lb) of propellant remaining and all five of its scientific instruments are working properly.[113] The orbiter can reportedly continue orbiting Mars for several years with its remaining propellant.[114]
A 17-day communications blackout occurred from 6 to 22 June 2015 while Mars' orbit took it behind the Sun from Earth's view.[51]: 52
On 24 September 2015, ISRO released its Mars Atlas, a 120-page scientific
atlas containing images and data from the Mars Orbiter Mission's first year in orbit.[115]
During 18 to 30 May 2016, a communication whiteout occurred with Earth coming directly between Sun and Mars. Due to high solar radiation, sending commands to spacecraft was avoided and payload operations were suspended.[118]
On 17 January 2017, MOM's orbit was altered to avoid the impending eclipse season. With a burn of eight 22 N thrusters for 431 seconds, resulting in a velocity difference of 97.5 metres per second (351 km/h) using 20 kilograms (44 lb) of propellant (leaving 13 kg remaining), eclipses were avoided until September 2017. The battery is able to handle eclipses of up to 100 minutes.[119]
On 19 May 2017, MOM reached 1,000 days (973
sols) in orbit around Mars. In that time, the spacecraft completed 388 orbits of the planet and relayed more than 715 images back to Earth. ISRO officials stated that it remains in good health.[120]
On 24 September 2018, MOM completed 4 years in its orbit around Mars, although the designed mission life was only six months. Over these years, MOM's Mars Colour Camera has captured over 980 images that were released to the public. The probe is still in good health and continues to work nominally.[121]
On 24 September 2019, MOM completed 5 years in orbit around Mars, sending 2 terabytes of imaging data, and had enough propellant to complete another year in orbit.[122]
On 1 July 2020, MOM was able to capture a photo of the Mars satellite
Phobos from 4200 km away.[123]
On 18 July 2021 Mars Colour Camera (MCC) captured full disc image of Mars from an altitude of about 75,000 km with spatial resolution about 3.7 km.[124]
In October 2022, ISRO admitted that it has lost the communication with MOM in April 2022, when it faced increasingly longer duration eclipses, including a seven-hour long eclipse that it was not designed to withstand. ISRO said the spacecraft was likely out of propellant and not recoverable.[31][30][29]
One of the first images of the surface of Mars taken by MOM on 25 September 2014
Three frame Mars Orbiter Mission Mars Color Camera mosaic of the
Syrtis Major region on 24 September 2015.
North Pole
Recognition
In 2014, China referred to India's successful Mars Orbiter Mission as the "Pride of Asia".[125] The Mars Orbiter Mission team won US-based
National Space Society's 2015
Space Pioneer Award in the science and engineering category. NSS said the award was given as the Indian agency successfully executed a Mars mission in its first attempt; and the spacecraft is in an elliptical orbit with a high apoapsis where, with its high resolution camera, it is taking full-disk colour imagery of Mars. Very few full disk images have ever been taken in the past, mostly on approach to the planet, as most imaging is done looking straight down in mapping mode. These images will aid planetary scientists.[126][127][128]
An illustration of the Mars Orbiter Mission spacecraft is featured on the reverse of the
₹2,000 currency note of India.[129]
An image taken by the Mars Orbiter Mission spacecraft was the cover photo of the November 2016 issue of National Geographic magazine, for their story "Mars: Race to the Red Planet".[130][131]
Follow-up mission
ISRO plans to develop and launch a follow-up mission called
Mars Orbiter Mission 2 (MOM-2 or Mangalyaan-2) with a greater scientific payload to Mars in 2024.[132][133][134] The orbiter will use
aerobraking to reduce
apoapsis of its initial orbit and reach an altitude more suitable for scientific observation.[135]
^"Mangalyaan". NASA. 2013. Retrieved 27 September 2014.
^Wall, Mike (23 September 2014).
"India's First Mars Probe Makes Historic Red Planet Arrival". Space.com. The MOM probe, which is named Mangalyaan (Sanskrit for "Mars craft"), executed a 24-minute orbital insertion burn Tuesday night, ending a 10-month space journey that began with the spacecraft's launch on Nov. 5, 2013
^Park, Madison (24 September 2014).
"India's spacecraft reaches Mars orbit ... and history". CNN. Retrieved 24 September 2014. India's Mars Orbiter Mission successfully entered Mars' orbit Wednesday morning, making India the first nation to arrive on its first attempt and the first Asian country to reach the Red Planet.
^
abAmos, Jonathan (24 September 2014).
"Why India's Mars mission is so cheap – and thrilling". BBC News. Retrieved 25 September 2014. Its measurements of other atmospheric components will dovetail very nicely with Maven and the observations being made by Europe's Mars Express. "It means we'll be getting three-point measurements, which is tremendous."
^
ab"SCIENCE PROGRAMME OFFICE (SPO), ISRO HEADQUARTERS". www.isro.gov.in. Archived from
the original on 3 October 2022. Retrieved 3 October 2022. It was also discussed that despite being designed for a life-span of six months as a technology demonstrator, the Mars Orbiter Mission has lived for about eight years in the Martian orbit with a gamut of significant scientific results on Mars as well as on the Solar corona, before losing communication with the ground station as a result of a long eclipse in April 2022. During the national meet, ISRO deliberated that the propellant must have been exhausted, and therefore, the desired attitude pointing could not be achieved for sustained power generation. It was declared that the spacecraft is non-recoverable, and attended its end-of-life. The mission will be ever-regarded as a remarkable technological and scientific feat in the history of planetary exploration.
^Savitha, A.; Chetwani, Rajiv R.; Ravindra, M.; Baradwaj, K. M. (2015). Onboard processor validation for space applications. 2015 International Conference on Advances in Computing, Communications and Informatics. 10–13 August 2015. Kochi, India.
doi:
10.1109/ICACCI.2015.7275677.
^"Mars full disc image by MCC – ISRO". www.isro.gov.in. Archived from
the original on 29 December 2021. Retrieved 29 December 2021. Full disc of Mars was imaged by Mars Colour Camera (MCC) of MOM on 18 July 2021 from an altitude of about 75,000km from Mars. The spatial resolution of the image is about 3.7 Km. Mars is seen entering in summer solstice in the northern hemisphere and it brings changes to the Martian ice caps, much of the ice cap is seen vaporized, adding water and carbon di-oxide to the atmosphere. Afternoon clouds are visible over Tempe Terra and near Martian North Polar region. Smaller cloud patches could also be seen over Naochis Terra region in the southern hemisphere.
Launches are separated by dots ( • ), payloads by commas ( , ), multiple names for the same satellite by slashes ( / ).
Cubesats are smaller. Crewed flights are underlined. Launch failures are marked with the † sign. Payloads deployed from other spacecraft are (enclosed in parentheses).