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    • By NASA
      Explore This Section Earth Earth Observer Editor’s Corner Feature Articles Meeting Summaries News Science in the News Calendars In Memoriam Announcements More Archives Conference Schedules Style Guide 9 min read
      NASA’s TROPICS Mission: Offering Detailed Images and Analysis of Tropical Cyclones
      Introduction
      Tropical cyclones represent a danger to life, property, and the economies of communities. Researchers who study tropical cyclones have focused on remote observations using space-based platforms to image these storms, inform forecasts, better predict landfall, and improve understanding of storm dynamics and precipitation evolution – see Figure 1.
      Figure 1. TROPICS imagery of Typhoon Kong-rey observed on October 29, 2024 near 205 GHz revealing a large and well-defined eye. Figure credit: U.S. Naval Research Laboratory The tropical cyclone community has leveraged data from Earth observing platforms for more than 30 years. These data have been retrieved from numerous instruments including: the Advanced Baseline Imager (ABI) on the National Oceanic and Atmospheric Administration’s (NOAA) Geostationary Operational Environmental Satellite (GOES)–Series R satellites; the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI); the Global Precipitation Measurement (GPM) Microwave Imager (GMI); the Special Sensor Microwave Imager/Sounder (SSMIS) on the Defense Meteorological Satellite (DSMP) satellites; the Advanced Microwave Scanning Radiometer (AMSR-E) on Aqua; AMSR2 on the Japan Aerospace Exploration Agency’s (JAXA) Global Change Observation Mission–Water (GCOM-W) mission; the Advanced Microwave Sounding Unit (AMSU) on Aqua and the Advanced Technology Microwave Sounder (ATMS) on the NASA–NOAA Suomi National Polar-Orbiting Partnership (Suomi NPP), NOAA-20, and NOAA-21; the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra and Aqua Platform; and the Visible Infrared Imaging Radiometer Suite (VIIRS) on Suomi NPP, as well as on the first two Joint Polar Satellite System (JPSS) missions (i.e., NOAA-20 and NOAA-21).
      Despite having decades of data at their disposal, scientists lack data from instruments placed in low-inclination orbits that provide more frequent views within tropical regions. This limitation is especially pronounced in the tropical and subtropical latitudes, which is where tropical storms develop and intensify.
      The NASA Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats (TROPICS) grew from the Precipitation and All-weather Temperature and Humidity (PATH) to address a need for obtaining three-dimensional (3D) temperature and humidity measurements as well as precipitation with a temporal revisit rate of one hour or better – see Figure 2. TROPICS uses multiple small satellites flying in a carefully engineered formation to obtain rapid revisits of measurements of precipitation structure within the storms, as well as temperature and humidity profiles, both within and outside of the storms, including the intensity of the upper-level warm core. In addition, the instruments provide a median revisit time of about one hour. The data gathered also informs changes in storm track and intensity and provides data to improve weather prediction models.
      The imagery is focused on inner storm structure (near 91 and 205 GHz), temperature soundings (near 118 GHz), and moisture soundings (near 183 GHz). Spatial resolution at nadir is approximately 24 km (16.8 mi) for temperature and 17 km (10.6 mi) for moisture and precipitation, covering a swath of approximately 2000 km (1243 mi) in width. Researchers can use TROPICS data to create hundreds of high-resolution images of tropical cyclones throughout their lifecycle.
      Figure 2. TROPICS space vehicle showing the CubeSat bus, radiometer payload, and deployed articulated solar array. Figure credit: Blue Canyon Technologies and MIT Lincoln Laboratory This article provides an overview of the two years of successful science operations of TROPICS, with a focus on the suite of geophysical Level-2 (L2) products (e.g., atmospheric vertical temperature and moisture profiles, instantaneous surface rain rate, and tropical cyclone intensity) and the science investigations resulting from these measurements. The complete article, available in the Proceedings Of The IEEE: Special Issue On Satellite Remote Sensing Of The Earth, provides more comprehensive details of the results.
      From Pathfinder to Constellation
      A single TROPICS satellite was launched as a Pathfinder vehicle on June 30, 2021, aboard a SpaceX Falcon 9 rideshare into a Sun-synchronous polar orbit. TROPICS was originally conceived as a six-satellite constellation, with two satellites launched into each of three low-inclination orbits. Regrettably, the first launch, on June 22, 2022 aboard an Astra Rocket 3.3, failed to reach orbit. While unfortunate, the mission could still proceed with four satellites and meet its baseline revisit rate requirement (with no margin), with the silver lining of an extra year of data gathered from TROPICS Pathfinder that allowed the tropical cyclone research community to prepare and test communications systems and data processing algorithms before the launch of the four remaining constellation satellites. These satellites were deployed on two separate launches – May 8, 2023 and May 26, 2023 aboard a Rocket Lab launch vehicle. The early testing accelerated calibration and validation for the constellation.
      Collecting Data Critical to Understanding Tropical Cyclones
      Tropical cyclone investigations require rapid quantitative observations to create 2D storm structure information. The four radiance data products in the TROPICS constellation [i.e., antenna temperature (L1a), brightness temperature (L1b), unified brightness temperature, and regularized scan pattern and limb-adjusted brightness temperature (L1c)] penetrate below the cloud top to gather data at greater frequency for a lower cost than current operational systems. The constellation data has been used to evaluate the development of the warm core and evolution of the ice water path within storms – two indicators of storm formation and subsequent changes in intensity.
      The upper-level warm core is key to tropical cyclone development and intensification. Precipitation may instigate rapid intensification through convective bursts that are characterized by expanding cold cloud tops, increasing ice scattering, lightning, and towers of intense rain and ice water that are indicative of strong updrafts. TROPICS frequencies provide a wealth of information on scattering by precipitation-sized ice particles in the eyewall and rainbands that will allow for researchers to track the macrostructure of convective bursts in tropical cyclones across the globe. In addition, TROPICS data helps clarify how variations in environmental humidity around tropical cyclones affect storm structure and intensification.
      Upper-level Warm Core
      Analysis of the upper-level warm core of a tropical cyclone reveals valuable information about the storm’s development. The tropical cyclone community is using data from TROPICS to understand the processes that lead to precipitating ice structure and the role it plays in intensification – see Figure 3. While the warm core has been studied for decades, TROPICS provides a new opportunity to get high-revisit rate estimates of the atmospheric vertical temperature profile. By pairing the temperature profile with the atmospheric vertical moisture profile, researchers can define the relative humidity in the lower-to-middle troposphere, which is critical to understanding the impact of dry environmental air on storm evolution and structure.
      Figure 3. TROPICS-3 imagery of Typhoon Kong-rey observed on October 29, 2024, a Category-5 storm that formed in the Pacific Ocean basin. Data gathered near 118 GHz was used to characterize temperature while data gathered near 205 GHz [right] revealed more about the inner structure of the storm. These data are used to define the warm core of the well-defined eye, located at 18.5° N. Figure Credit: U.S. Naval Research Laboratory Ice Water Path and Precipitation
      Another variable that helps to provide insight into the development of tropical cyclones is the ice water path, which details the total mass of ice present in a vertical column of the atmosphere and is therefore useful for characterizing the structure and intensity of these storms. Increasing ice water path can reflect strengthening convection within a storm and thereby be an indicator of likely intensification – see Figure 4. TROPICS is the first spaceborne sensor equipped with a 205-GHz channel that, along with the traditional 89, 118, and 183 GHz channels, is more sensitive to detecting precipitation-sized ice particles. In addition, the TROPICS Precipitation Retrieval and Profiling Scheme (PRPS) provides an estimate of precipitation. This scheme is based solely on the satellite radiances linked to precipitation rates, which can be used to generate products across time scales, from near-real-time to climatological scales.
      Figure 4. Global precipitation ice water path (PIWP) retrievals derived from TROPICS [top] compared to those derived using data from the GPM Dual-frequency Precipitation Radar (GPM DPR) [bottom] The strong agreement between the two datasets is further validated through case studies over hurricanes, where TROPICS observations correspond well with known storm characteristics. Figure Credit: Blackwell, W. J. et al. (2025) Collaborations and TROPICS Data in Action
      To evaluate and enhance the data gathered by TROPICS, the TROPICS application team enlisted the assistance of operational weather forecasters that formed the TROPICS Early Adopters program. In 2018, the program connected the application team to stakeholders interested in using TROPICS data for research, forecasting, and decision making. This collaboration improved approaches to diagnose and predict tropical cyclones. For example, the National Hurricane Center (NHC) found that the new TROPICS channel at 204.8 GHz offered the best approach to capture convective storm structure, followed by the more traditionally used 91-GHz channel. In addition, the U.S. Joint Typhoon Warning Center (JTWC) has been using TROPICS data to center-fix tropical cyclones and identify cloud formations. In particular, the JTWC team found that the 91-GHz channel was most useful for identifying cloud structure. Both NHC and JTWC found the TROPICS high revisit rate to be beneficial.
      In 2024, the TROPICS applications team developed the TROPICS Satellite Validation Module as part of the NOAA Hurricane Research Division’s annual Advancing the Prediction of Hurricanes Experiment (APHEX). The module coordinated data collection from NOAA’s Hurricane Hunter aircraft beneath TROPICS satellite overpasses to provide data to calibrate and validate TROPICS temperature, moisture, and precipitation measurements. Using this approach, the Hurricane Hunter team tracked Hurricane Ernesto over the central North Atlantic on August 15 and 16, 2024 and used the data to characterize the environment of Ernesto’s rain bands – see Figure 5.
      Figure 5. Brightness temperature (K) measured at 205 GHz from TROPICS-5 [right] and TROPICS-6 [left and center] from Hurricane Ernesto on August 15 and 16, 2024. The shaded circles denote 850–700 hPa relative humidity (%). Wind barbs are 850–700 hPa layer averaged winds (kt). Dropsonde data within 30 minutes of the TROPICS overpass times are plotted. Figure Credit: Blackwell, W. J. et al. (2025) In addition, the team used TROPICS observations in combination with GPM constellation precipitation estimates to characterize the lifecycle of Hurricane Franklin, which formed on August 19, 2023 and underwent a period of rapid intensification about eight days later. Intensification of the storm, in particular the period of rapid intensification (45 knot increase in maximum winds in 24 hours), occurred in association with a decrease in environmental vertical wind shear, a contraction of the radius of maximum precipitation, and an increase in the precipitation rate. Intensification ended with the formation of secondary rainbands and an outward shift in the radius of maximum precipitation.
      Conclusion
      TROPICS data offer the potential for improving forecasts from numerical weather prediction models and operational forecasts using its high spatial resolution and high revisit rates that enable enhanced characterization of tropical cyclones globally. To date, the TROPICS mission has produced a high-quality aggregate data record spanning 10 billion observations and 10 satellite years, using relatively low-cost microwave sounder constellations. All L1 (i.e., radiances) and L2 (i.e., geophysical products) data products and Algorithm Theoretical Basis Documents are available to the general public through the Goddard Earth Sciences Data and Information Services Center (GES DISC). The GES DISC data discussed in this article include L1 and L2 products for TROPICS-1, TROPICS-3, TROPICS-5, and TROPICS-6.
      TROPICS data has aided hurricane track forecasting for multiple storms as forecasters have used the data at multiple operational tropical cyclone forecast centers. Data gathered by TROPICS will soon be complemented by multiple commercial constellations that are coming online to improve the revisit rate and performance.
      William Blackwell 
      MIT Lincoln Laboratory
      wjb@ll.mit.edu
      Scott Braun
      NASA GSFC, TROPICS Project Scientist
      scott.a.braun@nasa.gov
      Stacy Kish
      Earth Observer Staff
      Earthspin.science@gmail.com
      Share








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      Last Updated Jun 09, 2025 Related Terms
      Earth Science View the full article
    • By European Space Agency
      On 12 March 2013, Galileo satellite GSAT0104, alongside its fellow In-Orbit Validation (IOV) satellites, made history by enabling the first position fix by Europe’s independent satellite navigation system Galileo. Now, after 12 years of service mostly in the area of Search and Rescue, GSAT0104 makes history again by becoming the first satellite in the Galileo constellation to be decommissioned.
      View the full article
    • By NASA
      3 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      Gateway’s HALO module at Northrop Grumman’s facility in Gilbert, Arizona, on April 4, 2025, shortly after its arrival from Thales Alenia Space in Turin, Italy. NASA/Josh Valcarcel NASA continues to mark progress on plans to work with commercial and international partners as part of the Gateway program. The primary structure of HALO (Habitation and Logistics Outpost) arrived at Northrop Grumman’s facility in Gilbert, Arizona, where it will undergo final outfitting and verification testing.
      HALO will provide Artemis astronauts with space to live, work, and conduct scientific research. The habitation module will be equipped with essential systems including command and control, data handling, energy storage, power distribution, and thermal regulation.
      Following HALO’s arrival on April 1 from Thales Alenia Space in Turin, Italy, where it was assembled, NASA and Northrop Grumman hosted an April 24 event to acknowledge the milestone, and the module’s significance to lunar exploration. The event opened with remarks by representatives from Northrop Grumman and NASA, including NASA’s Acting Associate Administrator for Exploration Systems Development Lori Glaze, Gateway Program Manager Jon Olansen, and NASA astronaut Randy Bresnik. Event attendees, including Senior Advisor to the NASA Administrator Todd Ericson, elected officials, and local industry and academic leaders, viewed HALO and virtual reality demonstrations during a tour of the facilities.
      Dr. Lori Glaze, acting associate administrator for NASA’s Exploration Systems Development Mission Directorate, and Dr. Jon B. Olansen, Gateway Program manager, on stage during an April 24, 2025, event at Northrop Grumman’s facility in Gilbert, Arizona, commemorating HALO’s arrival in the United States. Northrop Grumman While the module is in Arizona, HALO engineers and technicians will install propellant lines for fluid transfer and electrical lines for power and data transfer. Radiators will be attached for the thermal control system, as well as racks to house life support hardware, power equipment, flight computers, and avionics systems. Several mechanisms will be mounted to enable docking of the Orion spacecraft, lunar landers, and visiting spacecraft.
      Launching on top of HALO is the ESA (European Space Agency)-provided Lunar Link system which will enable communication between crewed and robotic systems on the Moon and to mission control on Earth. Once these systems are installed, the components will be tested as an integrated spacecraft and subjected to thermal vacuum, acoustics, vibration, and shock testing to ensure the spacecraft is ready to perform in the harsh conditions of deep space.
      In tandem with HALO’s outfitting at Northrop Grumman, the Power and Propulsion Element – a powerful solar electric propulsion system – is being assembled at Maxar Space Systems in Palo Alto, California. Solar electric propulsion uses energy collected from solar panels converted to electricity to create xenon ions, then accelerates them to more than 50,000 miles per hour to create thrust that propels the spacecraft.
      The element’s central cylinder, which resembles a large barrel, is being attached to the propulsion tanks, and avionics shelves are being installed. The first of three 12-kilowatt thrusters has been delivered to NASA’s Glenn Research Center in Cleveland for acceptance testing before delivery to Maxar and integration with the Power and Propulsion Element later this year.
      Learn More About Gateway Facebook logo @NASAGateway @NASA_Gateway Instagram logo @nasaartemis Linkedin logo @NASA Share
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      Last Updated Apr 25, 2025 ContactLaura RochonLocationJohnson Space Center Related Terms
      Artemis Artemis 4 Earth's Moon Exploration Systems Development Mission Directorate Gateway Space Station General Humans in Space Explore More
      2 min read NASA Welcomes Gateway Lunar Space Station’s HALO Module to US
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      Article 3 weeks ago 2 min read NASA Prepares Gateway Lunar Space Station for Journey to Moon
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    • By NASA
      A SpaceX Falcon 9 rocket stands vertical on Tuesday, Feb. 25, 2025, at Launch Complex 39A at NASA’s Kennedy Space Center ahead of Intuitive Machines’ IM-2 mission as part of the agency’s Commercial Lunar Payload Services initiative and Artemis campaign. SpaceX Sending instruments to the Moon supports a growing lunar economy on and off Earth, and the next flight of NASA science and technology is only days away. NASA’s CLPS (Commercial Lunar Payload Services) initiative is a lunar delivery service that sends NASA science and technology instruments to various geographic locations on the Moon using American companies. These rapid, cost-effective commercial lunar missions at a cadence of about two per year improve our understanding of the lunar environment in advance of future crewed missions to the Moon as part of the agency’s broader Artemis campaign.  
      Of the 11 active CLPS contracts, there have been three CLPS launches to date: Astrobotic’s Peregrine Mission One, which collected data in transit but experienced an anomaly that prevented it from landing on the Moon; Intuitive Machines’ IM-1 mission, which landed, tipped over, and operated on the lunar surface; and Firefly Aerospace’s Blue Ghost Mission One that is currently enroute and scheduled to land in early March 2025. The CLPS contract awards cover end-to-end commercial payload delivery services, including payload integration, launch from Earth, landing on the surface of the Moon, and mission operations. 
      NASA’s fourth CLPS flight is from Intuitive Machines with their IM-2 mission. The IM-2 mission is carrying NASA science and technology instruments to Mons Mouton, a lunar plateau just outside of 5 degrees of the South Pole of the Moon, closer to the pole than any preceding lunar mission.  
      Scheduled to launch no earlier than Wednesday and land approximately eight days later, Intuitive Machines’ Nova-C lander, named Athena, will carry three NASA instruments to the lunar South Pole region – the Polar Resources Ice Mining Experiment-1 (PRIME-1) suite and the Laser Retroreflector Array (LRA). 
      The PRIME-1 suite consists of two instruments, the TRIDENT drill (The Regolith Ice Drill for Exploring New Terrain) and MSolo (Mass Spectrometer observing lunar operations), which will work together to extricate lunar soil samples, known as regolith, from the subsurface and analyze their composition to further understand the lunar environment and gain insight on potential resources that can be extracted for future examination. 
      The meter-long TRIDENT drill is designed to extract lunar regolith, up to about three feet below the surface. It will also measure soil temperature at varying depths below the surface, which will help to verify existing lunar thermal models that are used for ice stability calculations and resource mapping. By drilling into the lunar regolith, information is gathered to help answer questions about the lunar regolith geotechnical properties, such as soil strength, both at the surface and in the subsurface that will help inform Artemis infrastructure objectives. The data will be beneficial when designing future systems for on-site resource utilization that will use local resources to create everything from landing pads to rocket fuel. The lead development organization for TRIDENT is Honeybee Robotics, a Blue Origin Company. 
      The MSOLO instrument is a mass spectrometer capable of identifying and quantifying volatiles (or gasses that easily evaporate) found at or beneath the lunar surface, including– if it’s present in the regolith within the drill’s reach – water and oxygen, brought to the surface by the TRIDENT drill. This instrument can also detect any gases that emanate from the lander, drilling process, and other payloads conducting operations on the surface. Using MSolo to study the volatile gases found on the Moon can help us understand how the lander’s presence might alter the local environment. The lead development organization is INFICON of Syracuse, New York, in partnership with NASA’s Kennedy Space Center in Florida. 
      NASA’s LRA is a collection of eight retroreflectors that enable precision laser ranging, which is a measurement of the distance between the orbiting or landing spacecraft to the reflector on the lander. The LRA instrument is passive, meaning it does not power on. It will function as a permanent location marker on the Moon for decades to come, similar to its predecessors. The lead development organization is NASA’s Goddard Space Flight Center in Greenbelt, Maryland. 
      In addition to the CLPS instruments, two technology demonstrations aboard IM-2 were developed through NASA’s Tipping Point opportunity. These are collaborations with the agency’s Space Technology Mission Directorate and industry that support development of commercial space capabilities and benefit future NASA missions.  
      Intuitive Machines developed a small hopping robot, Grace, named after Grace Hopper, computer scientist and mathematician. Grace will deploy as a secondary payload from the lander and enable high-resolution imaging and science surveying of the lunar surface, including permanently shadowed craters around the landing site. Grace is designed to bypass obstacles such as steep inclines, boulders, and craters to cover a lot of terrain while moving quickly, which is a valuable capability to support future missions on the Moon and other planets, including Mars. 
      Nokia will test a Lunar Surface Communications System that employs the same cellular technology here on Earth. Reconceptualized by Nokia Bell Labs to meet the unique requirements of a lunar mission, this tipping point technology aims to demonstrate proximity communications between the lander, a Lunar Outpost rover, and the hopper. 
      Launching as a rideshare alongside the IM-2 mission, NASA’s Lunar Trailblazer spacecraft also will begin its journey to lunar orbit where it will map the distribution of water – and other forms of water – on the Moon. 
      Future CLPS flights will continue to send payloads to the near side, far side, and South Pole regions of the Moon where investigations and exploration are informed by each area’s unique characteristics. With a pool of 13 American companies under CLPS, including a portfolio of 11 lunar deliveries by five vendors sending more than 50 individual science and technology instruments to lunar orbit and the surface of the Moon, NASA continues to advance long-term exploration of the Moon, and beyond to Mars.   

      View the full article
    • By NASA
      On Jan. 7, 1610, Italian astronomer Galileo Galilei peered through his newly improved 20-power homemade telescope at the planet Jupiter. He noticed three other points of light near the planet, at first believing them to be distant stars. Observing them over several nights, he noted that they appeared to move in the wrong direction with regard to the background stars and they remained in Jupiter’s proximity but changed their positions relative to one another. Four days later, he observed a fourth point of light near the planet with the same unusual behavior. By Jan. 15, Galileo correctly concluded that he had discovered four moons orbiting around Jupiter, providing strong evidence for the Copernican theory that most celestial objects did not revolve around the Earth.  
      Two of Galileo’s telescopes.National Geographic. Painting by Giuseppe Bertini (1858) of Galileo demonstrating his telescope to the Doge of Venice.gabrielevanin.it Page from Galileo’s notebook about his observations of Jupiter’s satellites.University of Michigan Special Collections Library. In March 1610, Galileo published his discoveries of Jupiter’s satellites and other celestial observations in a book titled Siderius Nuncius (The Starry Messenger). As their discoverer, Galileo had naming rights to Jupiter’s satellites. He proposed to name them after his patrons the Medicis and astronomers called them the Medicean Stars through much of the seventeenth century, although in his own notes Galileo referred to them by the Roman numerals I, II, III, and IV, in order of their distance from Jupiter. Astronomers still refer to the four moons as the Galilean satellites in honor of their discoverer.  

      In 1614, the German astronomer Johannes Kepler suggested naming the satellites after mythological figures associated with Jupiter, namely Io, Europa, Ganymede, and Callisto, but his idea didn’t catch on for more than 200 years. Scientists didn’t discover any more satellites around Jupiter until 1892 when American astronomer E.E. Barnard found Jupiter’s fifth moon Amalthea, much smaller than the Galilean moons and orbiting closer to the planet than Io. It was the last satellite in the solar system found by visual observation – all subsequent discoveries occurred via photography or digital imaging. As of today, astronomers have identified 95 moons orbiting Jupiter. 
      Image of Jupiter and three of its four Galilean satellites through an amateur telescope, similar to what Galileo might have seen. Hubble Space Telescope image of Jupiter and three of its four Galilean satellites during a rare triple transit. Although each of the Galilean satellites has unique features, such as the volcanoes of Io, the heavily cratered surface of Callisto, and the magnetic field of Ganymede, scientists have focused more attention on Europa due to the tantalizing possibility that it might be hospitable to life. In the 1970s, NASA’s Pioneer 10 and 11 and Voyager 1 and 2 spacecraft took ever increasingly detailed images of the large satellites including Europa during their flybys of Jupiter. The photographs revealed Europa to have the smoothest surface of any object in the solar system, indicating a relatively young crust, and also one of the brightest of any satellite indicating a highly reflective surface. These features led scientists to hypothesize that Europa is covered by an icy crust floating on a subsurface salty ocean. They further postulated that tidal heating caused by Jupiter’s gravity reforms the surface ice layer in cycles of melting and freezing.   

      Image of Europa taken by Pioneer 10 during its flyby of Jupiter in 1973. Image of Europa taken by Voyager 1 during its 1979 flyby of Jupiter. Image of Europa taken by Voyager 2 during its 1979 flyby of Jupiter. More detailed observations from NASA’s Galileo spacecraft that orbited Jupiter between 1995 and 2003 and completed 11 close encounters with Europa revealed that long linear features on its surface may indicate tidal or tectonic activity. Reddish-brown material along the fissures and in splotches elsewhere on the surface may contain salts and sulfur compounds transported from below the crust and modified by radiation. Observations from the Hubble Space Telescope and re-analysis of images from Galileo revealed possible plumes emanating from beneath Europa’s crust, lending credence to that hypothesis. While the exact composition of this material is not known, it likely holds clues to whether Europa may be hospitable to life.   
      Global view of Europa from the Galileo spacecraft. More detailed views of varied terrain on Europa from Galileo. Cutaway illustration of Europa’s icy crust, subsurface ocean and possible vents that transport material to the surface. Future robotic explorers of Europa may answer some of the outstanding questions about this unique satellite of Jupiter. NASA’s Europa Clipper set off in October 2024 on a 5.5-year journey to Jupiter. After its arrival in 2030, the spacecraft will enter orbit around the giant planet and conduct 49 flybys of Europa during its four-year mission. Managed by the Jet Propulsion Laboratory in Pasadena, California, and the Applied Physics Laboratory at Johns Hopkins University in Baltimore, Maryland, Europa Clipper will carry nine instruments including imaging systems and a radar to better understand the structure of the icy crust. Data from Europa Clipper will complement information returned by the European Space Agency’s JUICE (Jupiter Icy Moon Explorer) spacecraft. Launched in April 2023, JUICE will first enter orbit around Jupiter in 2031 and then enter orbit around Ganymede in 2034. The spacecraft also plans to conduct studies of Europa complementary with Europa Clipper’s. The two spacecraft should greatly increase our understanding of Europa and perhaps uncover new mysteries. 

      Illustration of the Europa Clipper spacecraft investigating Europa. Illustration of the JUICE spacecraft exploring Europa.European Space Agency. View the full article
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