T he Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) mission landed on Mars on 26 November 2018 in Elysium Planitia 1,2 , 38 years after the end of Viking 2 lander operations. At the time, Viking's seismometer 3 did not succeed in making any convincing Marsquake detections, due to its on-deck installation and high wind sensitivity. InSight therefore provides the first direct geophysical in situ investigations of Mars's interior structure by seismology 1,4. The Seismic Experiment for Interior Structure (SEIS) 5 monitors the ground acceleration with six axes: three Very Broad Band (VBB) oblique axes, sensitive to frequencies from tidal up to 10 Hz, and one vertical and two horizontal Short Period (SP) axes, covering frequencies from ~0.1 Hz to 50 Hz. SEIS is complemented by the APSS experiment 6 (InSight Auxiliary Payload Sensor Suite), which includes pressure and TWINS (Temperature and Winds for InSight) sensors and a magnetometer. These sensors monitor the atmospheric sources of seismic noise and signals 7. After seven sols (Martian days) of SP on-deck operation, with seismic noise comparable to that of Viking 3 , InSight's robotic arm 8 placed SEIS on the ground 22 sols after landing, at a location selected through analysis of InSight's imaging data 9. After levelling and noise assessment, the Wind and Thermal Shield was deployed on sol 66 (2 February 2019). A few days later, all six axes started continuous seismic recording, at 20 samples per second (sps) for VBBs and 100 sps for SPs. After onboard decimation, continuous records at rates from 2 to 20 sps and event records 5 at 100 sps are transmitted. Several layers of thermal protection and very low self-noise enable the SEIS VBB sensors to record the daily variation of the

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The martian surface is a natural laboratory for testing our understanding of the physics of aeolian (wind-related) processes in an environment different from that of Earth. Martian surface markings and atmospheric opacity are time-variable, indicating that fine particles at the surface are mobilized regularly by wind'"'. Regolith (unconsolidated surface material) at the Mars Exploration Rover Opportunity's landing site has been affected greatly by wind, which has created and reoriented bedforms, sorted grains, and eroded bedrock. Aeolian features here preserve a unique record of changing wind direction and wind strength. Here we present an in situ examination of a martian bright wind streak, which provides evidence consistent with a previously proposed formational model'''^ for such features. We also show that a widely used criterion for distinguishing between aeolian saltation-and suspension-dominated grain behaviour is different on Mars, and that estimated wind friction speeds between 2 and 3ms~', most recently from the northwest, are associated with recent global dust storms, providing ground truth for climate model predictions.Pre-landing orbiter observations of Opportunity's landing site showed bright and dark streaks tapering away from craters on the Meridiani plains. From observations of similar features distributed across many locations on Mars, streak orientations indicate formative wind directions'""*. High-resolution images within the 117 km X 18 km landing ellipse obtained over several years show bright streak directions that indicate winds from the northwest and southeast'. What has not been recognized previously, however, is that this apparent bimodality of wind direction has a significant time dependence. Images obtained before the major 2001 dust storm are more likely to show bright streaks oriented in the opposite direction from images obtained after the storm waned. Rare overlapping image pairs provide two examples of an individual streak changing orientation after the intervening 2001 dust storm (Fig.

It aims to determine the interior structure, composition and thermal state of Mars, as well as constrain present-day seismicity and impact cratering rates. Such information is key to understanding the differentiation and subsequent thermal evolution of Mars, and thus the forces that shape the planet's surface geology and volatile processes. Here we report an overview of the first ten months of geophysical observations by InSight. As of 30 September 2019, 174 seismic events have been recorded by the lander's seismometer, including over 20 events of moment magnitude M w = 3-4. The detections thus far are consistent with tectonic origins, with no impact-induced seismicity yet observed, and indicate a seismically active planet. An assessment of these detections suggests that the frequency of global seismic events below approximately M w = 3 is similar to that of terrestrial intraplate seismic activity, but there are fewer larger quakes; no quakes exceeding M w = 4 have been observed. The lander's other instruments-two cameras, atmospheric pressure, temperature and wind sensors, a magnetometer and a radiometer-have yielded much more than the intended supporting data for seismometer noise characterization: magnetic field measurements indicate a local magnetic field that is ten-times stronger than orbital estimates and meteorological measurements reveal a more dynamic atmosphere than expected, hosting baroclinic and gravity waves and convective vortices. With the mission due to last for an entire Martian year or longer, these results will be built on by further measurements by the InSight lander. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

A visible atmospheric optical depth of 0.9 was measured by the Spirit rover at Gusev crater and by the Opportunity rover at Meridiani Planum. Optical depth decreased by about 0.6 to 0.7% per sol through both 90-sol primary missions. The vertical distribution of atmospheric dust at Gusev crater was consistent with uniform mixing, with a measured scale height of 11.56 +/- 0.62 kilometers. The dust's cross section weighted mean radius was 1.47 +/- 0.21 micrometers (mm) at Gusev and 1.52 +/- 0.18 mm at Meridiani. Comparison of visible optical depths with 9-mm optical depths shows a visible-to-infrared optical depth ratio of 2.0 +/- 0.2 for comparison with previous monitoring of infrared optical depths.

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The energy source driving Jupiter's active meteorology is not understood. There are two main candidates: a poorly understood internal heat source and sunlight. Here we report observations of an active storm system possessing both lightning and condensation of water. The storm has a vertical extent of at least 50 km and a length of about 4,000 km. Previous observations of lightning on Jupiter have revealed both its frequency of occurrence and its spatial distribution, but they did not permit analysis of the detailed cloud structure and its dynamics. The present observations reveal the storm (on the day side of the planet) at the same location and within just a few hours of a lightning detection (on the night side). We estimate that the total vertical transport of heat by storms like the one observed here is of the same order as the planet's internal heat source. We therefore conclude that moist convection-similar to large clusters of thunderstorm cells on the Earth-is a dominant factor in converting heat flow into kinetic energy in the jovian atmosphere.