ESA's Exomars Schiaparelli Lander Lost

Essential data from the ExoMars Schiaparelli lander sent to its mothership Trace Gas Orbiter during the module’s descent to the Red Planet’s surface yesterday has been downlinked to Earth and is currently being analysed by experts.

Early indications from both the radio signals captured by the Giant Metrewave Radio Telescope (GMRT), an experimental telescope array located near Pune, India, and from orbit by ESA’s Mars Express, suggested the module had successfully completed most steps of its 6-minute descent through the martian atmosphere. This included the deceleration through the atmosphere, and the parachute and heat shield deployment, for example.

But the signals recorded by both Pune and Mars Express stopped shortly before the module was expected to touchdown on the surface. Discrepancies between the two data sets are being analysed by experts at ESA’s space operations centre in Darmstadt, Germany.

The detailed telemetry recorded by the Trace Gas Orbiter was needed to better understand the situation. At the same time as Schiaparelli’s descent, the orbiter was performing a crucial ‘Mars Orbit Insertion’ manoeuvre – which it completed successfully. These important data were recorded from Schiaparelli and beamed back to Earth in the early hours of Thursday morning.

link.

In fact, ESA stated the lander may have exploded.

NASA appears to have found what may be the wreckage.

NASA Approves Mars InSight Lander Launch for 2018 at Additional $180 Million Cost

NASA announced Sept. 2 that it has approved plans to launch a delayed Mars lander mission in 2018, although at an additional cost that could affect plans for later planetary missions.

The InSight Mars lander, originally scheduled for launch in March, will now launch no earlier than May 5, 2018, after NASA’s Science Mission Directorate formally approved the revised mission plan this week. That launch will allow a landing on Mars in November 2018.

NASA postponed the launch in December 2015 after a series of problems with one of its primary instruments, the Seismic Experiment for Interior Structure (SEIS), provided by the French space agency CNES. The instrument suffered a series of vacuum leaks that NASA concluded could not be fixed in time to permit a launch during a window that lasted about a month.

link.

Lander rocket exhaust effects on Europa regolith nitrogen assays

Lander rocket exhaust effects on Europa regolith nitrogen assays

Author:

Lorenz

Abstract:

Soft-landings on large worlds such as Europa or our Moon require near-surface retropropulsion, which leads to impingement of the rocket plume on the surface. Surface modification by such plumes was documented on Apollo and Surveyor, and on Mars by Viking, Curiosity and especially Phoenix. The low temperatures of the Europan regolith may lead to efficient trapping of ammonia, a principal component of the exhaust from monopropellant hydrazine thrusters. Deposited ammonia may react with any trace organics, and may overwhelm the chemical and isotopic signatures of any endogenous nitrogen compounds, which are likely rare on Europa. An empirical correlation of the photometrically-altered regions (‘blast zones’) around prior lunar and Mars landings is made, indicating A=0.02T1.5, where A is the area in m2 and W is the lander weight (thus, ~thrust) at landing in N: this suggests surface alteration will occur out to a distance of ~9 m from a 200 kg lander on Europa.

How to Detect Europa's Subsurface Ocean Through Radio Waves Using a Lander

Prospects of Passive Radio Detection of a Subsurface Ocean on Europa with a Lander

Authors:

Romero-Wolf et al

Abstract:

We estimate the sensitivity of a lander-based instrument for the passive radio detection of a subsurface ocean beneath the ice shell of Europa, expected to be between 3 km - 30 km thick, using Jupiter's decametric radiation. A passive technique was previously studied for an orbiter. Using passive detection in a lander platform provides significant improvements due to largely reduced losses from surface roughness effects, longer integration times, and diminished dispersion due to ionospheric effects allowing operation at lower frequencies and a wider band. A passive sounder on-board a lander provides a low resource instrument sensitive to subsurface ocean at Europa up to depths of 6.9 km for high loss ice (16 dB/km two-way attenuation rate) and 69 km for pure ice (1.6 dB/km).

NASA Seeking Ways to Avoid Using SLS for Europa Mission(s)

Faced with a congressional mandate to add a lander to a planned mission to Jupiter’s icy moon Europa, NASA is considering launching the lander separately from the main mission.

In discussions Feb. 1 at a meeting of NASA’s Outer Planets Assessment Group in San Antonio, Texas, agency officials said they are considering how to add a lander to a mission under development to make multiple flybys of Europa, even though the lander will weigh significantly more than the main “clipper” spacecraft.

Curt Niebur, outer planets program scientist at NASA Headquarters, said at the meeting that the biggest challenge of adding the lander to the Europa mission is its mass: about 8,000 kilograms, to accommodate the propellant needed to land the spacecraft softly on the surface. He added that estimate was “very rough” based on the limited studies of lander concepts to date. By comparison, the clipper spacecraft alone would have a mass of only about 5,000 kilograms.

That additional mass would drive the selection of the launch vehicle, requiring the use of the Space Launch System. “If we co-manifest the lander and clipper, we’re only on SLS,” he said. “It’s still a slow boat, so to speak: you’d still do inner solar system gravity assists.”

link.

ExoMars Successfully Shipped to Baikonur

Europe's second mission to Mars has begun its journey from its birthplace in Cannes to its planned arrival at Mars on October 19. Since December 17 we've been able to watch every step of its journey, thanks to a stream of tweets from Albert Haldemann. He is overseeing the spacecraft's assembly, integration, and verification, and flew back and forth from Baikonur for the three trips required to transport ExoMars and all its equipment. Tweeting from Baikonur was technical operations officer Remy van Haarlem. I've Storified their tweets here, but include a few highlights below.

link.

Instrument for NASA InSight Mars Lander Will be Repaired in Time for 2016 Launch

The French-built instrument for NASA’s InSight Mars lander scheduled for launch in March is expected to be repaired in time for shipment to the United States in early January after developing a leak in its vacuum container, the president of the French space agency, CNES, said Dec. 8.

Briefing reporters here at the COP21 United Nations Climate Change Conference, Jean-Yves Le Gall said the leak, which compromised the required high-precision vacuum chamber carrying InSight sensors, was caused by a defective weld that is applied to close off the tank.

The leak’s cause has been identified and a new weld performed, Le Gall said. Tests to confirm the new weld’s integrity are underway and, assuming no problems, will be completed in time to ship the instrument to the United States in the first week of January. It will then be integrated into the InSight lander in preparation for the March launch.

link.

Mars InSight Lander may be Forced to Delay to Next Mars Launch Window

Consideration is being given to delaying the launch of NASA's Mars InSight lander mission. The problem has to do with the French seismometer. There is a persistent leak inside the seismometer that has been hard to fix. Given that this payload is one of the two prime functions of InSight if the issue is not resolved in the next month or so then the launch will be slipped until the next favorable Mars launch window opens.

link.

1/3 Model of China's 2020 Mars Mission

link.

Okay, India.  You beat the Chinese to Mars (and the Russians going back for that matter...and the Japanese), time to get there again before the Chinese.

Touchdown on Venus!

Touchdown on Venus: Analytic wind Models and a Heuristic Approach to Estimating Landing Dispersions

Author:

Lorenz

Abstract:

The ‘landing ellipse’ or region of uncertainty within which an unguided probe to Venus may be expected to land is calculated. The region can be usefully seen as the convolution of three different factors: an initial circular delivery uncertainty which is smeared at a grazing entry angle onto the planetary sphere, an along-track uncertainty due to atmospheric density and vehicle aerodynamic variations during hypersonic entry, and a descent dispersion due to uncertain and/or variable zonal and meridional winds. This decomposition allows the various contributions to be instructively exposed and conveniently traded-off, without conducting explicit entry and descent dynamics simulations. It is seen that for descent durations and delivery errors typical of past Venus missions, the zonal wind contribution (determined with an analytic fit to Pioneer Venus tracking data) generally dominates, causing a ~200 km E-W (99%) dispersion, with meridional dispersions being about 4 times smaller. However, when entry angles become shallower than about 8 degrees, the along-track dispersions may dominate, with the resulting ellipse becoming longer or wider depending on the entry azimuth. The analytic wind descriptions presented here may be applied to scientific problems, such as the dispersal of volcanic plumes or impact ejecta.

Enceladus Explorer: A Proposed Lander to Search for Life on Enceladus

A lander mission to probe subglacial water on Saturn׳s moon Enceladus for life

Authors:

Konstantinidis et al

Abstract:

The plumes discovered by the Cassini mission emanating from the south pole of Saturn׳s moon Enceladus and the unique chemistry found in them have fueled speculations that Enceladus may harbor life. The presumed aquiferous fractures from which the plumes emanate would make a prime target in the search for extraterrestrial life and would be more easily accessible than the moon׳s subglacial ocean.

A lander mission that is equipped with a subsurface maneuverable ice melting probe will be most suitable to assess the existence of life on Enceladus. A lander would have to land at a safe distance away from a plume source and melt its way to the inner wall of the fracture to analyze the plume subsurface liquids before potential biosignatures are degraded or destroyed by exposure to the vacuum of space. A possible approach for the in situ detection of biosignatures in such samples can be based on the hypothesis of universal evolutionary convergence, meaning that the independent and repeated emergence of life and certain adaptive traits is wide-spread throughout the cosmos. We thus present a hypothetical evolutionary trajectory leading towards the emergence of methanogenic chemoautotrophic microorganisms as the baseline for putative biological complexity on Enceladus. To detect their presence, several instruments are proposed that may be taken aboard a future subglacial melting probe.

The “Enceladus Explorer” (EnEx) project funded by the German Space Administration (DLR), aims to develop a terrestrial navigation system for a subglacial research probe and eventually test it under realistic conditions in Antarctica using the EnEx-IceMole, a novel maneuverable subsurface ice melting probe for clean sampling and in situ analysis of ice and subglacial liquids. As part of the EnEx project, an initial concept study is foreseen for a lander mission to Enceladus to deploy the IceMole near one of the active water plumes on the moon׳s South-Polar Terrain, where it will search for signatures of life.

The general mission concept is to place the Lander at a safe distance from an active plume. The IceMole would then be deployed to melt its way through the ice crust to an aquiferous fracture at a depth of 100 m or more for an in situ examination for the presence of microorganisms.

The driving requirement for the mission is the high energy demand by the IceMole to melt through the cold Enceladan ices. This requirement is met by a nuclear reactor providing 5 kW of electrical power. The nuclear reactor and the IceMole are placed on a pallet lander platform. An Orbiter element is also foreseen, with the main function of acting as a communications relay between Lander and Earth.

After launch, the Lander and Orbiter will perform the interplanetary transfer to Saturn together, using the on-board nuclear reactor to power electric thrusters. After Saturn orbit insertion, the Combined Spacecraft will continue using Nuclear Electric Propulsion to reach the orbit of Enceladus. After orbit insertion at Enceladus, the Orbiter will perform a detailed reconnaissance of the South-Polar Terrain. At the end of the reconnaissance phase, the Lander will separate from the Orbiter and an autonomously guided landing sequence will place it near one of the active vapor plumes. Once landed, the IceMole will be deployed and start melting through the ice, while navigating around hazards and towards a target subglacial aquiferous fracture.

An initial estimation of the mission׳s cost is given, as well as recommendations on the further development of enabling technologies. The planetary protection challenges posed by such a mission are also addressed.

Is This China's Sample Return Probe for the Moon?

NASA Starts Construction of InSight Mars Mission

It’s time to get ready for Mars, again! NASA has given the approval to begin construction on its 2016 mission, the Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport (InSight) mission.

As the mission implies, the lander (which isn’t moveable) will focus on learning more about the inside of Mars. The idea is to figure out how terrestrial planets are “differentiated” inside between core, mantle and crust. Also, watchers of the Mars program may recognize some parts of the lander, as it will borrow the design from the successful Phoenix mission in 2008.

link.

Transient Thermal Interactions Between Lunar Rovers, Landers and Lunar Regolith

Characterizing transient thermal interactions between lunar regolith and surface spacecraft

Authors:

Hager et al

Abstract:

We present a new method, its development, implementation, and verification, for calculating the transient thermal interaction between lunar regolith and moving spacecraft travelling across the surface of the Moon. Regolith temperatures can be determined for lunar landscapes as defined by laser altimeter remote sensing data refined with local crater and boulder models. The purpose of this approach is to enable more detailed, dynamic thermal analyses of mobile systems on the lunar surface rather than relying on worst case, boundary condition design approaches typically used for spacecraft thermal engineering.

This new simulation method is based on integrating models that represent small and large scale landscapes; reproduce regolith and boulder temperatures on the Moon; define the position of the Sun; and perform ray tracing to determine infrared and solar heat fluxes between passing objects and the surface. The thermal model of the lunar regolith enhances established models with a slope-and depth-dependent density. The simulation results were verified against remote sensing data obtained from the Diviner Lunar Radiometer Experiment of the Lunar Reconnaissance Orbiter (LRO) and from other sources cited in the literature.

The verification results for isolated regolith surface patches showed a deviation from established models of about ±3–6 K (±1–6%) during lunar day, and lunar night. For real landscapes such as Crater Calippus and Crater Marius A, the deviation is less than ±15 K (±10%) compared to remote sensing data for the majority of measured data points. Only in regions with presumed different regolith material properties, such as steep slopes or depressions, or in regions with a low resolution on the topographic map, were the deviations up to 100 K (60%). From the results, empirical equations were derived, which can be used for worst case calculations or to calculate initial temperatures for more elaborate time marching numerical models.

The proposed new method could be further enhanced to address scientific questions by incorporating more detailed regolith and boulder models, or be used as-is to evaluate the dynamic thermal envelope of moving spacecraft.