This article needs to be updated.(March 2020) |
Mission type | Mars orbiter | ||||||||||
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Operator | ESA · Roscosmos | ||||||||||
COSPAR ID | 2016-017A | ||||||||||
SATCAT no. | 41388 | ||||||||||
Website | http://exploration.esa.int/jump.cfm?oid=46475 | ||||||||||
Mission duration | Planned: 7 years [1] [2] Elapsed: 8 years, 8 months, 1 day | ||||||||||
Spacecraft properties | |||||||||||
Manufacturer | Thales Alenia Space | ||||||||||
Launch mass | 4,332 kg [3] | ||||||||||
Payload mass | Instruments: 113.8 kg (251 lb) [4] Schiaparelli: 577 kg (1,272 lb) [4] | ||||||||||
Dimensions | 3.2 × 2 × 2 m (10.5 × 6.6 × 6.6 ft) [4] | ||||||||||
Power | ~2000 W [4] | ||||||||||
Start of mission | |||||||||||
Launch date | 14 March 2016, 09:31 UTC [5] | ||||||||||
Rocket | Proton-M/Briz-M | ||||||||||
Launch site | Baikonur 200/39 | ||||||||||
Contractor | Khrunichev | ||||||||||
Orbital parameters | |||||||||||
Reference system | Areocentric | ||||||||||
Regime | Circular | ||||||||||
Eccentricity | 0 | ||||||||||
Periareion altitude | 400 km (250 mi) | ||||||||||
Apoareion altitude | 400 km (250 mi) | ||||||||||
Inclination | 74 degrees | ||||||||||
Period | 2 hours | ||||||||||
Epoch | Planned | ||||||||||
Mars orbiter | |||||||||||
Orbital insertion | 19 October 2016, 15:24 UTC [6] | ||||||||||
Transponders | |||||||||||
Band | X band UHF band | ||||||||||
Frequency | 390–450 MHz | ||||||||||
TWTA power | 65 W | ||||||||||
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ESA mission insignia for the ExoMars 2016 launch, featuring the Trace Gas Orbiter (left) and Schiaparelli (right). ExoMars programme |
The ExoMars Trace Gas Orbiter (TGO or ExoMars Orbiter) is a collaborative project between the European Space Agency (ESA) and the Russian Roscosmos agency that sent an atmospheric research orbiter and the Schiaparelli demonstration lander to Mars in 2016 as part of the European-led ExoMars programme. [7] [8] [9]
The Trace Gas Orbiter delivered the Schiaparelli lander on 16 October 2016, which crashed on the surface due to a premature release of the parachute. [10]
The orbiter began aerobraking in March 2017 to lower its initial orbit of 200 by 98,000 km (120 by 60,890 mi). Aerobraking concluded on 20 February 2018 when a final thruster firing resulted in an orbit of 200 by 1,050 km (120 by 650 mi). [11] Additional thruster firings every few days raised the orbiter to a circular "science" orbit of 400 km (250 mi), which was achieved on 9 April 2018. [12]
A key goal is to gain a better understanding of methane (CH4) and other trace gases present in the Martian atmosphere that could be evidence for possible biological activity. The programme was originally intended to follow with the Kazachok lander and the Rosalind Franklin rover in 2022, [13] [14] which would have searched for biomolecules and biosignatures; the TGO would have operated as the communication link for the ExoMars lander and rover and provided communication for other Mars surface probes with Earth.
Investigations with space and Earth-based observatories have demonstrated the presence of a small amount of methane on the atmosphere of Mars that seems to vary with location and time. [15] [16] [17] This may indicate the presence of microbial life on Mars, or a geochemical process such as volcanism or hydrothermal activity. [18] [19] [20] [21]
The challenge to discern the source of methane in the atmosphere of Mars prompted the independent planning by ESA and NASA of one orbiter each that would carry instruments in order to determine if its formation is of biological or geological origin, [22] [23] as well as its decomposition products such as formaldehyde and methanol.
ExoMars Trace Gas Orbiter was born out of the nexus of ESA's Aurora programme ExoMars flagship and NASA's 2013 and 2016 Mars Science Orbiter (MSO) concepts. [24] [25] It became a flexible collaborative proposal within NASA and ESA to send a new orbiter-carrier to Mars in 2016 as part of the European-led ExoMars mission. [9] On the ExoMars side, ESA authorised about half a billion Euros in 2005 for a rover and mini-station; eventually this evolved into being delivered by an orbiter rather than a cruise stage. [26]
NASA's Mars Science Orbiter (MSO) was originally envisioned in 2008 as an all-NASA endeavour aiming for a late 2013 launch. [24] [25] NASA and ESA officials agreed to pool resources and technical expertise and collaborate to launch only one orbiter. [27] The agreement, called the Mars Exploration Joint Initiative, was signed in July 2009 and proposed to use an Atlas rocket launcher instead of a Soyuz rocket, which significantly altered the technical and financial setting of the European ExoMars mission. Since the rover was originally planned to be launched along with the TGO, a prospective agreement would require that the rover lose enough weight to fit aboard the Atlas launch vehicle with NASA's orbiter. [28] Instead of reducing the rover's mass, it was nearly doubled when the mission was combined with other projects to a multi-spacecraft programme divided over two Atlas V launches: [27] [29] the ExoMars Trace Gas Orbiter (TGO) was merged into the project, carrying a meteorological lander planned for launch in 2016. The European orbiter would carry several instruments originally meant for NASA's MSO, so NASA scaled down the objectives and focused on atmospheric trace gases detection instruments for their incorporation in ESA's ExoMars Trace Gas Orbiter. [4] [9] [25]
Under the FY2013 budget President Barack Obama released on 13 February 2012, NASA terminated its participation in ExoMars due to budgetary cuts in order to pay for the cost overruns of the James Webb Space Telescope. [30] With NASA's funding for this project cancelled, most of ExoMars' plans had to be restructured. [31]
On 15 March 2012, the ESA's ruling council announced it would press ahead with its ExoMars program in partnership with the Russian space agency Roscosmos, which planned to contribute two heavy-lift Proton launch vehicles and an additional entry, descent and landing system to the 2020 rover mission. [32] [33] [34] [35] [36]
Under the collaboration proposal with Roscosmos, the ExoMars mission was split into two parts: the orbiter/lander mission in March 2016 that includes the TGO and a 2.4 m (7 ft 10 in) diameter stationary lander built by ESA named Schiaparelli, [37] and the Rosalind Franklin rover mission in 2020 [13] (postponed to 2022 [38] ). Both missions are using a Proton-M rocket.
The Trace Gas Orbiter and descent module Schiaparelli completed testing and were integrated to a Proton rocket at the Baikonur Cosmodrome in Kazakhstan in mid-January 2016. [39] The launch occurred at 09:31 UTC on 14 March 2016. [5] Four rocket burns occurred in the following 10 hours before the descent module and orbiter were released. [40] A signal from the spacecraft was received at 21:29 UTC that day, confirming that the launch was successful and the spacecraft were functioning properly. [41]
Shortly after separation from the probes, a Brazilian ground telescope recorded small objects in the vicinity of the Briz-M upper booster stage, suggesting that the Briz-M stage exploded a few kilometres away, without damaging the orbiter or lander. [42] Briefing reporters in Moscow, the head of Roscosmos denied any anomaly and made all launch data available for inspection. [43]
The Schiaparelli lander separated from the TGO orbiter on 16 October 2016, [44] three days before it arrived on Mars, and entered the atmosphere at 21,000 km/h (13,000 mph; 5.8 km/s). [45] Schiaparelli transmitted about 600 megabytes of telemetry during its landing attempt, [46] [47] before it impacted the surface at 540 km/h (340 mph). [48]
The TGO was injected into Mars orbit on 19 October 2016 and underwent 11 months of aerobraking (March 2017 to February 2018), reducing its orbital speed by 3,600 km/h (2,200 mph) and its orbit from an initial 98,000 by 200 km (60,890 by 120 mi) down to 1,050 by 200 km (650 by 120 mi). Additional thruster firings through mid-April circularised the spacecraft's orbit to 400 km (250 mi), and full science activities began on 21 April 2018. [49] [50]
The TGO separated from the ExoMars Schiaparelli demonstration lander and would have provided it with telecommunication relay for 8 Martian solar days (sols) after landing. Then the TGO gradually underwent aerobraking for seven months into a more circular orbit for science observations and will eventually provide communications relay for the future Rosalind Franklin rover and will continue serving as a relay satellite for future landed missions. [2] [52] [53]
The FREND instrument is currently mapping hydrogen levels to a maximum depth of 1 m (3 ft 3 in) beneath the Martian surface. [54] [55] Locations where hydrogen is found may indicate water-ice deposits, which could be useful for future crewed missions.
Particularly, the mission is in the process of characterising spatial, temporal variation, and localisation of sources for a broad list of atmospheric trace gases. If methane (CH4) is found in the presence of propane (C3H8) or ethane (C2H6), that would be a strong indication that biological processes are involved. [56] However, if methane is found in the presence of gases such as sulfur dioxide (SO2), that would be an indication that the methane is a byproduct of geological processes. [57]
The nature of the methane source requires measurements of a suite of trace gases in order to characterise potential biochemical and geochemical processes at work. The orbiter has very high sensitivity to (at least) the following molecules and their isotopomers: water (H2O), hydroperoxyl (HO2), nitrogen dioxide (NO2), nitrous oxide (N2O), methane (CH4), acetylene (C2H2), ethylene (C2H4), ethane (C2H6), formaldehyde (H2CO), hydrogen cyanide (HCN), hydrogen sulfide (H2S), carbonyl sulfide (OCS), sulfur dioxide (SO2), hydrogen chloride (HCl), carbon monoxide (CO) and ozone (O3). Detection sensitivities are at levels of 100 parts per trillion, improved to 10 parts per trillion or better by averaging spectra which could be taken at several spectra per second. [58]
Like the Mars Reconnaissance Orbiter , the Trace Gas Orbiter is a hybrid science and telecom orbiter. [59] Its scientific payload mass is about 113.8 kg (251 lb) and consists of: [4] [60]
Due to the challenges of entry, descent and landing, Mars landers are highly constrained in mass, volume and power. For landed missions, this places severe constraints on antenna size and transmission power, which in turn greatly reduce direct-to-Earth communication capability in comparison to orbital spacecraft. As an example, the capability downlinks on Spirit and Opportunity rovers had only 1⁄600 the capability of the Mars Reconnaissance Orbiter downlink. Relay communication addresses this problem by allowing Mars surface spacecraft to communicate using higher data rates over short-range links to nearby Mars orbiters, while the orbiter takes on the task of communicating over the long-distance link back to Earth. This relay strategy offers a variety of key benefits to Mars landers: increased data return volume, reduced energy requirements, reduced communications system mass, increased communications opportunities, robust critical event communications and in situ navigation aid. [65] NASA provided an Electra telecommunications relay and navigation instrument to assure communications between probes and rovers on the surface of Mars and controllers on Earth. [66] The TGO will provide the Rosalind Franklin rover with telecommunications relay; it will also serve as a relay satellite for future landed missions. [2]
The spacecraft took its first photos of the surface of Mars on 15 April 2018. [67] The first year of science operations [68] yielded a wealth of new data and scientific discoveries, including: new observations of the atmospheric composition and structure, [69] [70] water-ice cloud enhancement during a global dust storm, [71] new measurements of the atmospheric thermal structure and density, [72] estimations of the timespan of the climate record of the south polar ice sheet, [73] confirmation of dry-processes being responsible for Recurring Slope Lineae in Hale crater, [74] identifying a variety of ice and non-ice related active processes occurring on the surface in colour, [75] and high-resolution maps of shallow subsurface Hydrogen, increasing the known amounts of probably near-surface buried water ice. [76]
In April 2019, the science team reported their first methane results: TGO had detected no methane whatsoever, even though their data were more sensitive than the methane concentrations found using Curiosity , Mars Express , and ground-based observations. [77] [78]
Mars Express is a space exploration mission being conducted by the European Space Agency (ESA). The Mars Express mission is exploring the planet Mars, and is the first planetary mission attempted by the agency. "Express" originally referred to the speed and efficiency with which the spacecraft was designed and built. However, "Express" also describes the spacecraft's relatively short interplanetary voyage, a result of being launched when the orbits of Earth and Mars brought them closer than they had been in about 60,000 years.
The planet Mars has been explored remotely by spacecraft. Probes sent from Earth, beginning in the late 20th century, have yielded a large increase in knowledge about the Martian system, focused primarily on understanding its geology and habitability potential. Engineering interplanetary journeys is complicated and the exploration of Mars has experienced a high failure rate, especially the early attempts. Roughly sixty percent of all spacecraft destined for Mars failed before completing their missions, with some failing before their observations could begin. Some missions have been met with unexpected success, such as the twin Mars Exploration Rovers, Spirit and Opportunity, which operated for years beyond their specification.
The Aurora programme was a human spaceflight programme of the European Space Agency (ESA) established in 2001. The objective was to formulate and then to implement a European long-term plan for exploration of the Solar System using robotic spacecraft and human spaceflight to investigate bodies holding promise for traces of life beyond the Earth.
ExoMars is an astrobiology programme of the European Space Agency (ESA).
The Mars Telecommunications Orbiter (MTO) was a cancelled Mars mission that was originally intended to launch in 2009 and would have established an Interplanetary Internet between Earth and Mars. The spacecraft would have arrived in a high orbit above Mars in 2010 and relayed data packets to Earth from a variety of Mars landers, rovers and orbiters for as long as ten years, at an extremely high data rate. Such a dedicated communications satellite was thought to be necessary due to the vast quantity of scientific information to be sent to Earth by landers such as the Mars Science Laboratory.
Timeline for the Mars Reconnaissance Orbiter (MRO) lists the significant events of the launch, aerobraking, and transition phases as well as subsequent significant operational mission events; by date and brief description.
The Mars general circulation model is the result of a research project by NASA to understand the nature of the general circulation of the atmosphere of Mars, how that circulation is driven and how it affects the climate of Mars in the long term.
The idea of sending humans to Mars has been the subject of aerospace engineering and scientific studies since the late 1940s as part of the broader exploration of Mars. Long-term proposals have included sending settlers and terraforming the planet. Currently, only robotic landers and rovers have been on Mars. The farthest humans have been beyond Earth is the Moon, under the U.S. National Aeronautics and Space Administration (NASA) Apollo program which ended in 1972.
A Mars landing is a landing of a spacecraft on the surface of Mars. Of multiple attempted Mars landings by robotic, uncrewed spacecraft, ten have had successful soft landings. There have also been studies for a possible human mission to Mars including a landing, but none have been attempted.
The Mars Exploration Joint Initiative (MEJI) is an agreement signed between United States' space agency, NASA, and Europe's space agency, ESA to join resources and expertise in order to continue the exploration of the planet Mars. The agreement was signed in Washington D.C. in October 2009, between NASA administrator Charles Bolden and ESA director-general Jean-Jacques Dordain.
Rosalind Franklin, previously known as the ExoMars rover, is a planned robotic Mars rover, part of the international ExoMars programme led by the European Space Agency and the Russian Roscosmos State Corporation. The mission was scheduled to launch in July 2020, but was postponed to 2022. The Russian invasion of Ukraine has caused an indefinite delay of the programme, as the member states of the ESA voted to suspend the joint mission with Russia; in July 2022, ESA terminated its cooperation on the project with Russia. As of May 2022, the launch of the rover is not expected to occur before 2028 due to the need for a new non-Russian landing platform.
Delta-Differential One-Way Ranging is an interplanetary radio-tracking and navigation technique.
Schiaparelli EDM was a failed Entry, Descent, and Landing Demonstrator Module (EDM) of the ExoMars programme—a joint mission of the European Space Agency (ESA) and the Russian Space Agency Roscosmos. It was built in Italy and was intended to test technology for future soft landings on the surface of Mars. It also had a limited but focused science payload that would have measured atmospheric electricity on Mars and local meteorological conditions.
The following outline is provided as an overview of and topical guide to Mars:
The Atmospheric Chemistry Suite (ACS) is a science payload consisting of three infrared spectrometer channels aboard the ExoMars Trace Gas Orbiter (TGO) orbiting Mars since October 2016. The three channels are: the near-infrared channel (NIR), the mid-infrared channel (MIR), and the far infrared channel.
The Fine-Resolution Epithermal Neutron Detector (FREND) is a neutron detector that is part of the instrument payload on board the Trace Gas Orbiter (TGO), launched to Mars in March 2016. This instrument is currently mapping hydrogen levels to a maximum depth of 1 m beneath the Martian surface, thus revealing shallow water ice distribution. This instrument has an improved resolution of 7.5 times over the one Russia contributed to NASA's 2001 Mars Odyssey orbiter.
Nadir and Occultation for MArs Discovery (NOMAD) is a 3-channel spectrometer on board the ExoMars Trace Gas Orbiter (TGO) launched to Mars orbit on 14 March 2016.
The reported presence of methane in the atmosphere of Mars is of interest to many geologists and astrobiologists, as methane may indicate the presence of microbial life on Mars, or a geochemical process such as volcanism or hydrothermal activity.
Determining the origin of methane on Mars can only be addressed by looking at methane isotopologues and at higher alkanes (ethane, propane).