BepiColombo
Template:Short description Template:Use British English Template:Use dmy dates Template:Infobox spaceflight
BepiColombo is a joint mission of the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) to the planet Mercury.<ref name="Amos">Template:Cite news</ref> The mission comprises two satellites launched together: the Mercury Planetary Orbiter (MPO) and Mio (Mercury Magnetospheric Orbiter, MMO).<ref name="Miopressrelease">Template:Cite press release</ref> The mission will perform a comprehensive study of Mercury, including characterization of its magnetic field, magnetosphere, and both interior and surface structure. It was launched on an Ariane 5<ref name="ariane"/> rocket on 20 October 2018 at 01:45 UTC, with an arrival at Mercury planned for November 2026, after a flyby of Earth, and two flybys of Venus. It will complete six flybys of Mercury.<ref name="FACTS"/><ref name="esa20161125">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The mission was approved in November 2009, after years in proposal and planning as part of the European Space Agency's Horizon 2000+ programme;<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> it is the last mission of the programme to be launched.<ref name="scaling back"/>
On 15 May 2024, ESA reported that a "glitch" prevented the spacecraft's thrusters from operating at full power during a scheduled manoeuvre on 26 April.<ref name="x457">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> On 2 September, ESA reported that to compensate for the reduced available thrust, a revised trajectory had been developed that would add 11 months to the cruise, delaying the expected arrival date from 5 December 2025 to November 2026.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
NamesEdit
BepiColombo is named after Giuseppe "Bepi" Colombo (1920–1984), a scientist, mathematician and engineer at the University of Padua, Italy, who first proposed the interplanetary gravity assist manoeuvre used by the 1974 Mariner 10 mission, a technique now used frequently by planetary probes.
Mio, the name of the Mercury Magnetospheric Orbiter, was selected from thousands of suggestions by the Japanese public. In Japanese, Mio means a waterway, and according to JAXA, it symbolizes the research and development milestones reached thus far, and wishes for safe travel ahead. JAXA said the spacecraft will travel through the solar wind just like a ship traveling through the ocean.<ref name="Miopressrelease"/> In Chinese and Japanese, Mercury is known as the "water star" (水星) according to wǔxíng.
Following its Earth flyby in April 2020, BepiColombo was briefly mistaken for a near-Earth asteroid, receiving the provisional designation Template:Mp.<ref name="2020GL2a">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="2020GL2b">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="2020GL2c">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
MissionEdit
The mission involves three components, which will separate into independent spacecraft upon arrival at Mercury.<ref>Template:Cite conference</ref>
- Mercury Transfer Module (MTM) for propulsion, built by ESA.
- Mercury Planetary Orbiter (MPO) built by ESA.
- Mercury Magnetospheric Orbiter (MMO) or Mio built by JAXA.
During the launch and cruise phases, these three components are joined together (with the Magnetospheric Orbiter Sunshield and Interface or MOSIF between Mio and MPO)<ref name="MOSIF"/> to form the Mercury Cruise System (MCS).<ref name="Flyby 2018"/><ref name="Arrival 2018"/>
The prime contractor for ESA is Airbus Defence and Space.<ref name="sci.esa.int">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> ESA is responsible for the overall mission, the design, development assembly and test of the propulsion and MPO modules, and the launch. The two orbiters, which are operated by mission controllers based in Darmstadt, Germany, were successfully launched together on 20 October 2018.<ref name=launched>Template:Cite news</ref> The launch took place on Ariane flight VA245 from Europe’s Spaceport in Kourou, French Guiana.<ref>Template:Cite news</ref> The spacecraft will have an eight-year interplanetary cruise to Mercury using solar-electric propulsion (ion thrusters) and gravity assists from Earth, Venus and eventual gravity capture at Mercury.<ref name="FACTS"/> ESA's Cebreros, Spain Template:Convert ground station is planned to be the primary ground facility for communications during all mission phases.
Expected to arrive in Mercury orbit in November 2026, the Mio and MPO satellites will separate and observe Mercury in collaboration for one year, with a possible one-year extension.<ref name="FACTS"/> Although originally expected to enter orbit in December 2025, thruster issues discovered in September 2024 before its 4th flyby resulted in a delayed arrival of November 2026.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The orbiters are equipped with scientific instruments provided by various European countries and Japan. The mission will characterize the solid and liquid iron core (Template:Frac of the planet's radius) and determine the size of each.<ref>Science with BepiColombo ESA, Accessed: 23 October 2018</ref> The mission will also complete gravitational and magnetic field mappings. Russia provided gamma ray and neutron spectrometers to verify the existence of water ice in polar craters that are permanently in shadow from the Sun's rays.
Mercury is too small and hot for its gravity to retain any significant atmosphere over long periods of time, but it has a "tenuous surface-bounded exosphere"<ref>Template:Cite journal</ref> containing hydrogen, helium, oxygen, sodium, calcium, potassium and other trace elements. Its exosphere is not stable as atoms are continuously lost and replenished from a variety of sources. The mission will study the exosphere composition and dynamics, including generation and escape.
ObjectivesEdit
The main objectives of the mission are:<ref name="ISAS homepage"/><ref name="FACTS2">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
- Study the origin and evolution of a planet close to its parent star
- Study Mercury's form, interior, structure, geology, composition and craters
- Investigate Mercury's exosphere, composition and dynamics, including generation and escape
- Study Mercury's magnetised envelope (magnetosphere) – structure and dynamics
- Investigate the origin of Mercury's magnetic field
- Verify Einstein's theory of general relativity by measuring the parameters gamma and beta of the parameterized post-Newtonian formalism with high accuracy.<ref>{{#invoke:citation/CS1|citation
|CitationClass=web }}</ref><ref>Einstein's general relativity reveals new quirk of Mercury's orbit Emily Conover Science News 11 April 2018</ref>
DesignEdit
The stacked spacecraft will take eight years to position itself to enter Mercury orbit. During this time it will use solar-electric propulsion and nine gravity assists, flying past the Earth and Moon in April 2020, Venus in 2020 and 2021, and six Mercury flybys between 2021 and 2025.<ref name="FACTS"/>
The stacked spacecraft left Earth with a hyperbolic excess velocity of Template:Cvt. Initially, the craft was placed in a heliocentric orbit similar to that of Earth. After both the spacecraft and Earth completed one and a half orbits, it returned to Earth to perform a gravity-assist maneuver and is deflected towards Venus. Two consecutive Venus flybys reduce the perihelion near to the Sun–Mercury distance with almost no need for thrust. A sequence of six Mercury flybys will lower the relative velocity to Template:Cvt. After the fourth Mercury flyby, the craft will be in an orbit similar to that of Mercury and will remain in the general vicinity of Mercury (see [1]). Four final thrust arcs reduce the relative velocity to the point where Mercury will "weakly" capture the spacecraft in November 2026 into polar orbit. Only a small maneuver is needed to bring the craft into an orbit around Mercury with an apocentre of Template:Convert. The orbiters then separate and will adjust their orbits using chemical thrusters.<ref name="Data Center">{{#invoke:citation/CS1|citation |CitationClass=web }} Template:PD-notice</ref><ref name="mission design">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
HistoryEdit
The BepiColombo mission proposal was selected by ESA in 2000. A request for proposals for the science payload was issued in 2004.<ref name='Howell'>BepiColombo: Joint Mission to Mercury Elizabeth Howell Space.com 21 October 2018</ref> In 2007, Astrium was selected as the prime contractor, and Ariane 5 chosen as the launch vehicle.<ref name='Howell'/> The initial target launch of July 2014 was postponed several times, mostly because of delays on the development of the solar electric propulsion system.<ref name='Howell'/> The total cost of the mission was estimated in 2017 as US$2 billion.<ref>BepiColombo Mercury mission tested for journey into 'pizza oven' Stephen Clarke Spaceflight Now 17 July 2017</ref>
ScheduleEdit
Template:Legend2Template:·Template:Legend2Template:·Template:Legend2Template:·Template:Legend2Template:·Template:Legend2
For more detailed animation, see this video
Template:Asof, the mission schedule is:<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
| Date | Event | Comment | ||
|---|---|---|---|---|
| 20 October 2018, 01:45 UTC | Launch | |||
| 10 April 2020, 04:25 UTC |
Earth flyby | 1.5 years after launch | ||
| 15 October 2020, 03:58 UTC | First Venus flyby | According to Johannes Benkhoff of ESA, the probe may possibly be capable of detecting phosphine – the chemical allegedly discovered in the Venusian atmosphere in September 2020 – during this and the following flyby. He stated that "we do not know if our instrument is sensitive enough".<ref>Template:Cite news</ref> On 15 October 2020, the ESA reported the flyby was a success.<ref>{{#invoke:citation/CS1|citation | CitationClass=web
}}</ref> | |
| 10 August 2021, 13:51 UTC |
Second Venus flyby | 1.35 Venus years after first Venus flyby. Flyby was a success, and saw BepiColombo come within Template:Convert of Venus' surface.<ref>{{#invoke:citation/CS1|citation | CitationClass=web
}}</ref><ref>Template:Cite news</ref> | |
| 1 October 2021, 23:34:41 UTC |
First Mercury flyby | Passed Template:Convert from Mercury's surface.<ref>Template:Cite tweet</ref> Occurred on what would have been the 101st birthday of Giuseppe Colombo. | ||
| 23 June 2022, 09:44 UTC |
Second Mercury flyby | 2 orbits (3.00 Mercury years) after 1st Mercury flyby. Closest approach of about Template:Convert altitude.<ref>{{#invoke:citation/CS1|citation | CitationClass=web
}}</ref> | |
| 19 June 2023, 19:34 UTC |
Third Mercury flyby | >3 orbits (4.12 Mercury years) after 2nd Mercury flyby. Closest approach of about Template:Convert altitude.<ref>{{#invoke:citation/CS1|citation | CitationClass=web
}}</ref><ref>Template:Cite news</ref> | |
| Template:Nowrap, 21:48 UTC | Fourth Mercury flyby | ~4 orbits (5.04 Mercury years) after 3rd Mercury flyby. Closest approach of about Template:Convert altitude.<ref>{{#invoke:citation/CS1|citation | CitationClass=web
}}</ref> | |
| 1 December 2024, 14:23 UTC | Fifth Mercury flyby | 1 orbit (1.00 Mercury year) after 4th Mercury flyby. Closest approach about Template:Convert altitude.<ref>{{#invoke:citation/CS1|citation | CitationClass=web
}}</ref> | |
| 8 January 2025, 05:58:52 UTC | Sixth Mercury flyby | ~0.43 orbits (0.43 Mercury years) after 5th Mercury flyby. Closest approach about Template:Convert altitude.<ref>{{#invoke:citation/CS1|citation | CitationClass=web
}}</ref><ref>{{#invoke:citation/CS1|citation |
CitationClass=web
}}</ref> |
| November 2026 | Mercury orbit insertion | Spacecraft separation; ~7 Mercury years after 6th Mercury flyby | ||
| 2027 | Template:Nowrap | 1.13 Mercury years after orbit insertion? | ||
| April 2028 | End of nominal mission | 5.82 Mercury years after orbit insertion | ||
| April 2029 | End of extended mission | 9.98 Mercury years after orbit insertion |
ComponentsEdit
Mercury Transfer ModuleEdit
| QinetiQ T6 | Performance <ref>Qualification of the T6 Thruster for BepiColombo Template:Webarchive R. A. Lewis, J. Pérez Luna, N. Coombs. 30th International Symposium on Space Technology and Science 34th International Electric Propulsion Conference and 6th Nano-satellite Symposium, Hyogo-Kobe, Japan, 4–10 July 2015</ref><ref>QinetiQ's T6 and T5 Ion Thruster Electric Propulsion System Architectures and Performances Template:Webarchive Mark Hutchins, Huw Simpson. 30th International Symposium on Space Technology and Science 34th International Electric Propulsion Conference and 6th Nano-satellite Symposium, Hyogo-Kobe, Japan, 4–10 July 2015</ref> | ||
|---|---|---|---|
| Type | Kaufman Ion Engine | ||
| Units on board | citation | CitationClass=web
}}</ref><ref>{{#invoke:citation/CS1|citation |
CitationClass=web
}}</ref> |
| Diameter | Template:Cvt | ||
| Max. thrust | 145 mN each | ||
| Specific impulse (Isp) |
4300 seconds | ||
| Propellant | Xenon | ||
| Total power | 4628 W |
The Mercury Transfer Module (MTM) has a mass of Template:Cvt, including Template:Cvt of xenon propellant, and is located at the base of the stack. Its role is to carry the two science orbiters to Mercury and to support them during the cruise.
The MTM is equipped with a solar electric propulsion system as the main spacecraft propulsion. Its four QinetiQ-T6 ion thrusters operate singly or in pairs for a maximum combined thrust of 290 mN,<ref>Template:Cite conference</ref> making it the most powerful ion engine array ever operated in space. The MTM supplies electrical power for the two hibernating orbiters as well as for its solar electric propulsion system thanks to two Template:Convert solar panels.<ref name="MPO page">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Depending on the probe's distance to the Sun, the generated power will range between 7 and 14 kW, each T6 requiring between 2.5 and 4.5 kW according to the desired thrust level.
The solar electric propulsion system has typically very high specific impulse and low thrust. This leads to a flight profile with months-long continuous low-thrust braking phases, interrupted by planetary gravity assists, to gradually reduce the velocity of the spacecraft. Moments before Mercury orbit insertion, the MTM will be jettisoned from the spacecraft stack.<ref name='MPO page'/> After separation from the MTM, the MPO will provide Mio all necessary power and data resources until Mio is delivered to its mission orbit; separation of Mio from MPO will be accomplished by spin-ejection.
Mercury Planetary OrbiterEdit
The Mercury Planetary Orbiter (MPO) has a mass of Template:Cvt and uses a single-sided solar array capable of providing up to 1000 watts and featuring Optical Solar Reflectors to keep its temperature below Template:Cvt. The solar array requires continuous rotation keeping the Sun at a low incidence angle in order to generate adequate power while at the same time limiting the temperature.<ref name="MPO page"/>
The MPO will carry a payload of 11 instruments, comprising cameras, spectrometers (IR, UV, X-ray, γ-ray, neutron), a radiometer, a laser altimeter, a magnetometer, particle analysers, a Ka-band transponder, and an accelerometer. The payload components are mounted on the nadir side of the spacecraft to achieve low detector temperatures, apart from the MERTIS and PHEBUS spectrometers located directly at the main radiator to provide a better field of view.<ref name="MPO page"/>
A high-temperature-resistant Template:Cvt diameter high-gain antenna is mounted on a short boom on the zenith side of the spacecraft. Communications will be on the X-band and Ka-band with an average bit rate of 50 kbit/s and a total data volume of 1550 Gbit/year. ESA's Cebreros, Spain Template:Convert ground station is planned to be the primary ground facility for communications during all mission phases.<ref name="MPO page"/>
Science payloadEdit
The science payload of the Mercury Planetary Orbiter consists of eleven instruments:<ref name="MMO objectives"/><ref name="MPO Instruments 2008">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
- BepiColombo Laser Altimeter (BELA), developed by DLR in cooperation with the University of Bern, the Max Planck Institute for Solar System Research (MPS) and the Instituto de Astrofísica de Andalucía.<ref name="www2.mps.mpg.de">{{#invoke:citation/CS1|citation
|CitationClass=web }}</ref>
- Italian Spring Accelerometer (ISA), developed by Italy
- Mercury Magnetometer (MPO-MAG, MERMAG), developed by Germany and United Kingdom<ref name="MPO page"/>
- Mercury Radiometer and Thermal Infrared Spectrometer (MERTIS), developed by Germany
- Mercury Gamma-ray and Neutron Spectrometer (MGNS), developed by Russia
- Mercury Imaging X-ray Spectrometer (MIXS), developed and built by the University of Leicester, the Max Planck Institute for Solar System Research (MPS) and the Max Planck Institute for Extraterrestrial Physics (MPE).<ref>{{#invoke:citation/CS1|citation
|CitationClass=web }}</ref><ref name="FraserCarpenter2010">Template:Cite journal</ref>
- Mercury Orbiter Radio-science Experiment (MORE), developed by Italy and the United States
- Probing of Hermean Exosphere by Ultraviolet Spectroscopy (PHEBUS), developed by France and Russia
- Search for Exosphere Refilling and Emitted Neutral Abundances (SERENA),<ref>{{#invoke:citation/CS1|citation
|CitationClass=web }}</ref> made up of 2 neutral and 2 ionised particle analysers:
- ELENA (Emitted Low-Energy Neutral Atoms) developed by Italy;
- STROFIO (STart from a ROtating Field mass spectrOmeter) developed by United States;<ref>{{#invoke:citation/CS1|citation
|CitationClass=web }} Template:PD-notice</ref>
- MIPA (Miniature Ion Precipitation Analyser) developed by Sweden;
- PICAM (Planetary Ion CAMera) developed by the Space Research Institute (Institut für Weltraumforschung, IWF), Russian Space Research Institute (IKI), Institut de recherche en sciences de l'environnement (CETP/IPSL), European Space Research and Technology Centre (ESTEC), Research Institute for Particle and Nuclear Physics (KFKI-RMKI) and the Max Planck Institute for Solar System Research (MPS).<ref name="www2.mps.mpg.de"/>
- Spectrometers and Imagers for MPO BepiColombo Integrated Observatory System (SIMBIO-SYS), high resolution stereo cameras and a visual and near infrared spectrometer, developed by Italy, France and Switzerland
- Solar Intensity X-ray and Particle Spectrometer (SIXS), developed by Finland and United Kingdom.
Mio (Mercury Magnetospheric Orbiter)Edit
Mio, or the Mercury Magnetospheric Orbiter (MMO), developed and built mostly by Japan, has the shape of a short octagonal prism, Template:Cvt long from face to face and Template:Cvt high.<ref name='ISAS homepage'/><ref>Template:Cite journal</ref> It has a mass of Template:Cvt, including a Template:Cvt scientific payload consisting of 5 instrument groups, 4 for plasma and dust measuring run by investigators from Japan, and one magnetometer from Austria.<ref name='ISAS homepage'/><ref name="MMO brochure 2015">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
Mio will be spin stabilized at 15 rpm with the spin axis perpendicular to the equator of Mercury. It will enter a polar orbit at an altitude of Template:Cvt, outside of MPO's orbit.<ref name="MMO brochure 2015"/> The top and bottom of the octagon act as radiators with louvers for active temperature control. The sides are covered with solar cells which provide 90 watts. Communications with Earth will be through a Template:Cvt diameter X-band phased array high-gain antenna and two medium-gain antennas operating in the X-band. Telemetry will return 160 Gb/year, about 5 kbit/s over the lifetime of the spacecraft, which is expected to be greater than one year. The reaction and control system is based on cold gas thrusters. After its release in Mercury orbit, Mio will be operated by Sagamihara Space Operation Center using Usuda Deep Space CenterTemplate:'s Template:Cvt antenna located in Nagano, Japan.<ref name="MMO objectives">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
Science payloadEdit
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Mio carries five groups of science instruments with a total mass of Template:Cvt:<ref name='ISAS homepage'/><ref name='MMO objectives'/>
- Mercury Plasma Particle Experiment (MPPE), studies the plasma and neutral particles from the planet, its magnetosphere, and the solar wind. It will employ these instruments:
- Mercury Electron Analyzers (MEA1 and MEA2)
- Mercury Ion Analyzer (MIA)
- Mass Spectrum Analyzer (MSA), developed by Laboratory of Plasma Physics (LPP), Max Planck Institute for Solar System Research (MPS), IDA of Technical University of Braunschweig and Institute of Space and Astronautical Science (ISAS) <ref>{{#invoke:citation/CS1|citation
|CitationClass=web }}</ref>
- High-Energy Particle instrument for electrons (HEP-ele)
- High-Energy Particle instrument for Ions (HEP-ion)
- Energetic Neutrals Analyzer (ENA)
- Mercury Magnetometer (MMO-MGF), studies Mercury's magnetic field, magnetosphere, and interplanetary solar wind
- Plasma Wave Investigation (PWI), studies the electric field, electromagnetic waves, and radio waves from the magnetosphere and solar wind
- Mercury Sodium Atmosphere Spectral Imager (MSASI), studies the thin sodium atmosphere of Mercury
- Mercury Dust Monitor (MDM), studies dust from the planet and interplanetary space
Magnetospheric Orbiter Sunshield and InterfaceEdit
The Mio orbiter requires additional thermal control on the cruise to Mercury, in addition to umbilicals to the MPO. The European Space Agency thus provided the Magnetospheric Orbiter Sunshield and Interface (MOSIF), a white shroud that is shaped like a conical frustrum to provide clearance, as Mio is spun up during its separation in 2026, before being ejected from the MPO.<ref name="MOSIF">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="Flyby 2018">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="Arrival 2018">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
Mercury Surface Element (cancelled)Edit
The Mercury Surface Element (MSE) was cancelled in 2003 due to budgetary constraints.<ref name="scaling back">Template:Cite press release</ref> At the time of cancellation, MSE was meant to be a small, Template:Cvt, lander designed to operate for about one week on the surface of Mercury.<ref name="Data Center"/> Shaped as a Template:Cvt diameter disc, it was designed to land at a latitude of 85° near the terminator region. Braking manoeuvres would bring the lander to zero velocity at an altitude of Template:Cvt at which point the propulsion unit would be ejected, airbags inflated, and the module would fall to the surface with a maximum impact velocity of Template:Cvt. Scientific data would be stored onboard and relayed via a cross-dipole UHF antenna to either the MPO or Mio. The MSE would have carried a Template:Cvt payload consisting of an imaging system (a descent camera and a surface camera), a heat flow and physical properties package, an alpha particle X-ray spectrometer, a magnetometer, a seismometer, a soil penetrating device (mole), and a micro-rover.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
See alsoEdit
- Exploration of Mercury
- MESSENGER – the first spacecraft to orbit Mercury
ReferencesEdit
External linksEdit
- BepiColombo website by the European Space Agency
- BepiColombo Operations website by the European Space Agency
- BepiColombo website by JAXA
- BepiColombo website by JAXA's Institute of Space and Astronautical Science
- BepiColombo website by NASA's Solar System Exploration
- BepiColombo website by the National Space Science Data Center
- The BepiColombo mission to Mercury, edited by Johannes Benkhoff, Go Murakami and Ayako Matsuoka. Space Science Reviews. 216–217 (2020–2021)
- BepiColombo article on eoPortal by ESA
Template:Portal bar Template:Mercury (planet) Template:Mercury spacecraft Template:Venus spacecraft Template:ESA projects Template:Japanese space program Template:Planetary Missions Program Office Template:Solar System probes Template:Orbital launches in 2018 Template:2018 in space