|Website||ESA Webpage on TandEM/TSSM|
|Mission duration||2 years (proposed)|
|Launch mass||Orbiter: 1,613 kg (3,556 lb) |
Montgolfière :600 kg (1,300 lb)
Lander: 190 kg (420 lb)
|Start of mission|
|Launch date||Between 2020 and 2029 (proposed)|
|Rocket||Delta IV Heavy, Space Launch System Block IB, or Atlas V|
|Reference system||Titan Orbit|
|Semi-major axis||1,500 km (930 mi)|
|Orbital insertion||Between 2029-2038 (proposed)|
|Titan atmospheric probe|
|Spacecraft component||TSSM montgolfière|
|Spacecraft component||Titan Mare Explorer or other TSSM lander proposal|
|Landing site||Ligeia Mare|
Titan Saturn System Mission (TSSM) was a joint NASA–ESA proposal for an exploration of Saturn and its moons Titan and Enceladus,where many complex phenomena were revealed by Cassini . TSSM was proposed to launch in 2020,get gravity assists from Earth and Venus,and arrive at the Saturn system in 2029. The 4-year prime mission would include a two-year Saturn tour,a 2-month Titan aero-sampling phase,and a 20-month Titan orbit phase.
In 2009,a mission to Jupiter and its moons was given priority over Titan Saturn System Mission,although TSSM will continue to be assessed for possible development and launch.
This section needs to be updated.(June 2021)
The Titan Saturn System Mission (TSSM) was officially created in January 2009 by the merging of the ESA's Titan and Enceladus Mission (TandEM) with NASA's Titan Explorer (2007) study,although plans to combine both concepts date at least back to early 2008. TSSM was competing against the Europa Jupiter System Mission (EJSM) proposal for funding, and in February 2009 it was announced that NASA/ESA had given EJSM priority ahead of TSSM. TSSM continued to be studied for a later launch date, near the 2020s. Detailed assessment reports of the mission elements as well as a specific concept for a lake-landing module for Titan's lakes called Titan Mare Explorer (TiME) with the potential of becoming a part of the TSSM have been proposed in February and October 2009, respectively.
In 2014 it was thought the TSSM might have been revived for a launch on the SLS super-heavy-lift rocket.
The TSSM mission consists of an orbiter and two Titan exploration probes: a hot air balloon ("Montgolfier" type) that will float in Titan's clouds, and a lander that will splash down on one of its methane seas.
Both probes’ data are to be relayed to a Titan orbiter. They will be equipped to study Titan's features with instruments for imaging, radar profiling, and surface as well as atmospheric sampling, much more complete than done by the Cassini–Huygens mission.
The spacecraft will use several gravity assist flybys of other planets to enable it to reach Saturn. The baseline design envisaged a September 2020 launch, followed by four gravity assists (Earth–Venus–Earth–Earth), and arrival at Saturn 9 years later in October 2029. This is one of several available Earth-to-Saturn transfer options from the year 2018 through 2022. Current NASA plans do not give the TSSM a priority, however, and it is unlikely any of the proposed launch dates can be met.
Upon Saturn arrival, in October 2029, the orbiter's chemical propulsion system would place the flight system into orbit around Saturn, followed by a two-year Saturn Tour Phase, characterized by the deployment of the in situ elements, and including a minimum of seven close Enceladus flybys and 16 Titan flybys. During this period, repeated satellite gravity assists and maneuvers will reduce the energy needed to insert into Titan's orbit. As the craft completes its flyby by Enceladus, the orbiter will analyze the unusual cryovolcanic plumes at the moon's south pole.
The Montgolfière, a hot air balloon, would be released on approach to the first Titan flyby for ballistic entry into Titan's atmosphere for its six Earth months’ mission from April 2030 to October 2030. Based on Cassini–Huygens discoveries, the Montgolfière should be able to circumnavigate Titan at least once during its nominal lifetime at its deployment latitude of about 20°N, 10 kilometers above Titan's surface.
Numerous proposals have been brought forward with respect to the lake-lander concept. One of the most detailed plans so far is the so-called Titan Mare Explorer (TiME), which had originally been proposed as a separate scout mission, but might eventually be postponed and included in the TSSM.If approved, TiME would be released by the orbiter on its second Titan flyby. Due to Titan's haze layer and its distance to the Sun, the lander cannot be powered by solar panels and it would rely on the new Advanced Stirling Radioisotope Generator (ASRG), which is a prototype meant to provide availability of long-lived power supplies for landed networks and other planetary missions. The lander will target Ligeia Mare, a northern polar sea of liquid hydrocarbons at about 79°N. The probe will descend by parachute, like the Huygens probe of 2005. During the 6 hours of descent it will analyze the atmosphere and then splashdown on the liquid surface. The plutonium-powered craft's principal function is to sample and analyze organics on the surface for a period of about 3 to 6 months; this would be the first floating exploration of an extraterrestrial sea.
The major goals of the TSSM mission can be summarized under four categories:
At Titan, the science goals would be to provide information on such aspects as the composition of the surface and the geographic distribution of the various organic constituents; on the methane cycle and the methane reservoirs; on the ages of the surface features, and in particular on whether cryovolcanism and tectonism are actively ongoing or are relics of a more active past; on the presence or absence of ammonia, of a magnetic field and of a sub-surface ocean; on the chemistry that drives complex ion formation in the upper atmosphere; and on a large altitude range in the atmosphere, from 400–900 km, which remains poorly explored after Cassini. In addition, much remains to be understood about seasonal changes of the atmosphere at all levels, and the long-term escape of constituents to space.
TiME lander would splashdown on Ligeia Mare, a methane sea on Titan's northern hemisphere. It is believed that Titan's methane cycle is analogous to Earth's hydrologic cycle, with meteorological working fluid existing in liquid and gas phase. TiME would directly discern the methane cycle of Titan and help understand its similarities and differences to the hydrologic cycle on Earth.However, questions about the sources of re-supply of methane to the atmosphere remain to be answered. This world is built by organic activities which still operate and Cassini–Huygens findings suggest a world with a balance of geologic and atmospheric processes that is the solar system's best analogue to Earth. Moreover, an interior ocean discovered by Cassini, deep underneath Titan's dense atmosphere and surface is thought to be largely composed of liquid water. TSSM would be the first mission in the 50 years of space exploration where an extensive and interdisciplinary in situ survey of active organic chemistry and climate on the land, on the sea, and in the air of another world will take place.
Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine-and-a-half times that of Earth. It has only one-eighth the average density of Earth, but is over 95 times more massive.
Titan is the largest moon of Saturn, the second-largest in the Solar System and larger than any of the dwarf planets of the Solar System. It is the only moon known to have a dense atmosphere, and is the only known object in space other than Earth on which clear evidence of stable bodies of surface liquid has been found.
Cassini–Huygens, commonly called Cassini, was a space-research mission by NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) to send a space probe to study the planet Saturn and its system, including its rings and natural satellites. The Flagship-class robotic spacecraft comprised both NASA's Cassini space probe and ESA's Huygens lander, which landed on Saturn's largest moon, Titan. Cassini was the fourth space probe to visit Saturn and the first to enter its orbit, where it stayed from 2004 to 2017. The two craft took their names from the astronomers Giovanni Cassini and Christiaan Huygens.
A gravity assist, gravity assist maneuver, swing-by, or generally a gravitational slingshot in orbital mechanics, is a type of spaceflight flyby which makes use of the relative movement and gravity of a planet or other astronomical object to alter the path and speed of a spacecraft, typically to save propellant and reduce expense.
Huygens was an atmospheric entry robotic space probe that landed successfully on Saturn's moon Titan in 2005. Built and operated by the European Space Agency (ESA), launched by NASA, it was part of the Cassini–Huygens mission and became the first spacecraft to land on Titan and the farthest landing from Earth a spacecraft has ever made. The probe was named after the 17th-century Dutch astronomer Christiaan Huygens, who discovered Titan in 1655.
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This article provides a timeline of the Cassini–Huygens mission. Cassini was a collaboration between the United States' NASA, the European Space Agency ("ESA"), and the Italian Space Agency ("ASI") to send a probe to study the Saturnian system, including the planet, its rings, and its natural satellites. The Flagship-class uncrewed robotic spacecraft comprised both NASA's Cassini probe, and ESA's Huygens lander which was designed to land on Saturn's largest moon, Titan. Cassini was the fourth space probe to visit Saturn and the first to enter its orbit. The craft were named after astronomers Giovanni Cassini and Christiaan Huygens.
The Comet Rendezvous Asteroid Flyby (CRAF) was a cancelled plan for a NASA-led exploratory mission designed by the Jet Propulsion Laboratory during the mid-to-late 1980s and early 1990s, that planned to send a spacecraft to encounter an asteroid, and then to rendezvous with a comet and fly alongside it for nearly three years. The project was eventually canceled when it went over budget; most of the money still left was redirected to its twin spacecraft, Cassini–Huygens, destined for Saturn, so it could survive Congressional budget cutbacks. Most of CRAF's scientific objectives were later accomplished by the smaller NASA spacecraft Stardust and Deep Impact, and by ESA's flagship Rosetta mission.
The New Frontiers program is a series of space exploration missions being conducted by NASA with the purpose of furthering the understanding of the Solar System. The program selects medium-class missions which can provide high science returns.
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The exploration of Saturn has been solely performed by crewless probes. Three missions were flybys, which formed an extended foundation of knowledge about the system. The Cassini–Huygens spacecraft, launched in 1997, was in orbit from 2004 to 2017.
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Titan Mare Explorer (TiME) is a proposed design for a lander for Saturn's moon Titan. TiME is a relatively low-cost, outer-planet mission designed to measure the organic constituents on Titan and would have performed the first nautical exploration of an extraterrestrial sea, analyze its nature and, possibly, observe its shoreline. As a Discovery-class mission it was designed to be cost-capped at US$425 million, not counting launch vehicle funding. It was proposed to NASA in 2009 by Proxemy Research as a scout-like pioneering mission, originally as part of NASA's Discovery Program. The TiME mission design reached the finalist stage during that Discovery mission selection, but was not selected, and despite attempts in the U.S. Senate failed to get earmark funding in 2013. A related Titan Submarine has also been proposed.
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Journey to Enceladus and Titan (JET) is an astrobiology mission concept to assess the habitability potential of Enceladus and Titan, moons of Saturn.
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The following outline is provided as an overview of and topical guide to Saturn:
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