Warm Gas-Giant Exoplanet WASP-107 b

Click the image for higher resolution (1.1 MB)

This artist's concept shows what the exoplanet WASP-107 b could look like based on recent data gathered by NASA's James Webb Space Telescope along with previous observations from Hubble and other space- and ground-based telescopes.

WASP-107 b is a -warm Neptune' exoplanet orbiting a relatively small and cool star approximately 210 light-years from Earth, in the constellation Virgo. The planet is about 80% of the size of Jupiter in terms of volume, but has a mass less than 10% of Jupiter's, making it one of the least dense exoplanets known.

WASP-107 b orbits its star at a distance about 5 million miles (0.055 astronomical units, or AU), completing one circuit in 5.72 days. The planet is tidally locked: it rotates at the same rate that it orbits the star, which means that one side is permanently lit, with the other in continuous darkness, so there is no day–night cycle. The orbit of WASP-107 b is slightly elliptical, which means that the gravitational pull between the star and planet changes continuously as the planet moves toward and away from the star during its orbit.

Observations of 0.8- to 12-micron infrared light captured by the Hubble Space Telescope's WFC3 (Wide Field Camera 3), and Webb's NIRCam (Near-Infrared Camera), NIRSpec (Near-Infrared Spectrograph), and MIRI (Mid-Infrared Instrument), suggest that the planet has a relatively large core surrounded by a relatively small mass of hydrogen and helium gas, which has been inflated by tidal heating of the interior. WASP-107 b has not been directly imaged by any telescope.

Image Credit: NASA, ESA, CSA, R. Crawford (STScI)

Jupiter's Icy Moon Europa

Click on the image for higher resolution

Observations by the Hubble Space Telescope recently revealed water vapour in the atmosphere of Ganymede, one of Jupiter's moons. A new analysis of archival images and spectra has now revealed that water vapour is also present in the atmosphere of Jupiter's icy moon Europa. The analysis found that a water vapour atmosphere is present only on one hemisphere of the moon. This result advances our understanding of the atmospheric structure of icy moons, and helps lay the groundwork for upcoming science missions which will explore Jupiter's icy moons.

Europa – one of Jupiter's 79 moons – is both the sixth closest moon to Jupiter and the sixth largest moon in the Solar System. It is an icy orb larger than the dwarf planet Pluto with a smooth, icy surface scarred by cracks and fissures. The surface of the moon is a bleak environment with an average temperature of −170 °C and only a tenuous atmosphere. However, astronomers suspect that Europa harbours a vast ocean underneath its icy surface, which some scientists speculate could host extraterrestrial life. Now, for the first time, an astronomer has discovered evidence for persistent water vapour in the atmosphere of Europa.

Using a technique that recently resulted in the discovery of water vapour in the atmosphere of Jupiter's moon Ganymede, an astronomer has found evidence of water in Europa's trailing hemisphere – the portion of the moon that is always opposite to its direction of motion. The asymmetric distribution of water vapour was predicted by previous studies based on computer simulations, but had not previously been detected observationally.

“The observation of water vapour on Ganymede and on the trailing side of Europa advances our understanding of the atmospheres of icy moons,” commented Lorenz Roth of the KTH Royal Institute of Technology in Stockholm, Sweden, the author of this study. “The detection of a stable H2O abundance on Europa is surprising because the surface temperatures are so low.”

To make this discovery, Roth delved into archival Hubble datasets, selecting ultraviolet observations of Europa from 1999, 2012, 2014 and 2015 while the moon was at various orbital positions. These observations were all taken with one of Hubble's most versatile instruments – the Space Telescope Imaging Spectrograph (STIS). These ultraviolet STIS observations allowed Roth to determine the abundance of oxygen – one of the constituents of water – in Europa's atmosphere, and by interpreting the strength of emission at different wavelengths he was able to infer the presence of water vapour.

Previous observations of water vapour on Europa have been associated with transient plumes erupting through the ice, analogous to geysers here on Earth but more than 100 kilometers high. The phenomena seen in these plume studies were apparently transient inhomogeneities or blobs in the atmosphere. The new results, however, show similar amounts of water vapour to be present spread over a larger area in observations spanning from 1999 to 2015. This suggests the long-term presence of a water vapour atmosphere on Europa's trailing hemisphere. Despite the presence of water vapour on Europa's trailing hemisphere there is no indication of H2O on the leading hemisphere of Europa.

This reprocessed colour view of Jupiter's moon Europa was made from images taken by NASA's Galileo spacecraft in the late 1990s.

Image Credit: NASA/JPL-Caltech/SETI Institute

Image enhancement: Jean-Baptiste Faure

Hubble's sharpest image of Jupiter and Europa

Click on the image for higher resolution

This latest image of Jupiter, taken by the Hubble Space Telescope on 25 August 2020, was captured when the planet was 653 million kilometers from Earth. Hubble's sharp view is giving researchers an updated weather report on the monster planet's turbulent atmosphere, including a remarkable new storm brewing, and a cousin of the Great Red Spot changing colour – again. The new image also features Jupiter's icy moon Europa.

Image Credit: NASA, ESA, A. Simon (Goddard Space Flight Center), and M. H. Wong (University of California, Berkeley) and the OPAL team

Image enhancement: Jean-Baptiste Faure

Jupiter's Magnificent Swirling Clouds

Click on the image for higher resolution

A multitude of magnificent, swirling clouds in Jupiter's dynamic North North Temperate Belt is captured in this image from NASA's Juno spacecraft. Appearing in the scene are several bright-white "pop-up" clouds as well as an anticyclonic storm, known as a white oval. This color-enhanced image was taken at 4:58 p.m. EDT on Oct. 29, 2018 as the spacecraft performed its 16th close flyby of Jupiter. At the time, Juno was about 4,400 miles from the planet's cloud tops, at a latitude of approximately 40 degrees north.

Citizen scientists Gerald Eichstädt and Seán Doran created this image using data from the spacecraft's JunoCam imager. JunoCam's raw images are available at www.missionjuno.swri.edu/junocam for the public to peruse and process into image products.

Image Credit: Enhanced Image by Gerald Eichstädt and Sean Doran (CC BY-NC-SA)/NASA/JPL-Caltech/SwRI/MSSS

Mars 2020 Perseverance Rover

Click on the image for higher resolution

The Mars 2020 mission with its Perseverance rover is part of NASA's Mars Exploration Program, a long-term effort of robotic exploration of the Red Planet. The Mars 2020 mission addresses high-priority science goals for Mars exploration, including key Astrobiology questions about the potential for life on Mars.

The Mars 2020 Perseverance rover will investigate a region of Mars where the ancient environment may have been favorable for microbial life, probing the Martian rocks for evidence of past life. Throughout its investigation, it will collect samples of soil and rock, and cache them on the surface for potential return to Earth by a future mission.

Perseverance will carry an entirely new subsystem to collect and prepare Martian rocks and soil samples that includes a coring drill on its arm and a rack of sample tubes. About 30 of these sample tubes will be deposited at select locations for return on a potential future sample-retrieval mission. In laboratories on Earth, specimens from Mars could be analyzed for evidence of past life on Mars and possible health hazards for future human missions.

Two science instruments mounted on the rover's robotic arm will be used to search for signs of past life and determine where to collect samples by analyzing the chemical, mineral, physical and organic characteristics of Martian rocks. On the rover's mast, two science instruments will provide high-resolution imaging and three types of spectroscopy for characterizing rocks and soil from a distance, also helping to determine which rock targets to explore up close.

The Perseverance rover will use the same sky crane landing system as Curiosity, but will have the ability to land in more challenging terrain with two enhancements, making more rugged sites eligible as safe landing candidates.

Image Credit: NASA/JPL

Earth-size Habitable-zone Planet TOI 700 d

Click on the image for higher resolution

About 100 light-years away, in our own Milky Way galaxy, in the constellation Dorado, sits a planetary system named TOI 700. It is home to TOI 700 d (illustrated here), the first Earth-size habitable-zone planet discovered by TESS, NASA's Transiting Exoplanet Survey Satellite. Scientists confirmed the find, called TOI 700 d, using NASA's Spitzer Space Telescope and have modeled the planet's potential environments to help inform future observations. TOI 700 d is one of only a few Earth-size planets discovered in a star's habitable zone so far. Others include several planets in the TRAPPIST-1 system and other worlds discovered by NASA's Kepler Space Telescope.

While the exact conditions on TOI 700 d are unknown, scientists can use current information, like the planet's size and the type of star it orbits, to generate computer models and make predictions. Researchers at NASA's Goddard Space Flight Center in Greenbelt, Maryland, modeled 20 potential environments of TOI 700 d to gauge if any version would result in surface temperatures and pressures suitable for habitability.

Their 3D climate models examined a variety of surface types and atmospheric compositions typically associated with what scientists regard to be potentially habitable worlds. Because TOI 700 d is tidally locked to its star, the planet’s cloud formations and wind patterns may be strikingly different from Earth's. One simulation included an ocean-covered TOI 700 d with a dense, carbon-dioxide-dominated atmosphere similar to what scientists suspect surrounded Mars when it was young. The model atmosphere contains a deep layer of clouds on the star-facing side. Another model depicts TOI 700 d as a cloudless, all-land version of modern Earth, where winds flow away from the night side of the planet and converge on the point directly facing the star.

Image Credit: NASA/Goddard Space Flight Center

The Bay of Mont Saint-Michel, France

Click on the image for higher resolution (3.7 MB)

The Copernicus Sentinel-2 mission takes us over the Bay of Mont Saint-Michel in France. Lying between Brittany to the west and Normandy to the east, this remarkable bay, which is listed as a UNESCO world heritage site, sees some of the biggest tides in continental Europe. There can be up to 15 m difference between low and high water. When spring tides peak, the sea recedes about 15 km from the coast and when it returns it does so very quickly, making it a dangerous place to be. Sentinel-2 captured this image when the tide was out so that the vast area of sand dunes is exposed cut by meandering channels of shallow water. Three rivers empty into the bay: the Couesnon, the Sée and the Sélune.

The famous rocky islet of Mont Saint-Michel, visible as a small dark spot in the south of the bay, is about 1 km from the mouth of the Couesnon. Home to a Benedictine monastery and village, Mont Saint-Michel is also a UNESCO world heritage site and a mecca for tourists.

The bay, however, has been prone to silting up in the last couple of centuries. Actions by man, including farming and the building of a causeway to the island monastery, have added to this problem. A major campaign has ensured that Mont-Saint-Michel preserves its maritime character and remains an island. The main river into the bay, the Couesnon, for example, is being left to flow more freely so that sediments are washed out to sea.

Image Credit: ESA/Copernicus Sentinel-2

Curiosity rover on Mars

Click on the image for higher resolution (8.7 MB)

NASA's Curiosity rover took this selfie on the 2,553rd Martian day, or sol, of its mission. The rover drilled twice in this location, nicknamed "Glen Etive" (pronounced "glen EH-tiv"). About 300 meters (984 feet) behind the rover, Vera Rubin Ridge rises up. Behind it lies the floor of Gale Crater, which Curiosity is exploring, and the northern rim of the crater.

Just left of the rover are the two drill holes, called "Glen Etive 1" (right) and "Glen Etive 2" (left). Curiosity performed its first wet-chemistry experiment on a drilled sample at this location. The rover can analyze the chemical composition of rock samples by powderizing them with the drill, then dropping the samples into a portable lab in its belly called Sample Analysis at Mars (SAM).

This panorama is made up of 57 individual images taken by the Mars Hand Lens Imager (MAHLI), a camera on the end of the rover's robotic arm. The images are stitched together into a panorama; the robotic arm isn't visible in the parts of the images used in the composite.

MAHLI was built by Malin Space Science Systems in San Diego. The SAM instrument suite was built at Goddard Space Flight Center with significant elements provided by industry, university, and national and international NASA partners. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate in Washington. JPL designed and built the project's Curiosity rover.

Image Credit: NASA/JPL-Caltech/MSSS

Jupiter's Northern Hemisphere

Click on the image for higher resolution

This stunning image of Jupiter's stormy northern hemisphere was captured by NASA's Juno spacecraft as it performed a close pass of the gas giant planet. Some bright-white clouds can be seen popping up to high altitudes on the right side of Jupiter's disk.

Juno took the four images used to produce this color-enhanced view on May 29, 2019, between 3:52 a.m. EDT and 4:03 a.m. EDT, as the spacecraft performed its 20th science pass of Jupiter. At the time the images were taken, the spacecraft was between 18,600 kilometers (11,600 miles) and 8,600 kilometers (5,400 miles) above Jupiter's cloud tops, above a northern latitude spanning from about 59 to 34 degrees.

Image Credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill

Io's shadow on Jupiter

Click on the image for higher resolution

Jupiter's volcanically active moon Io casts its shadow on the planet in this dramatic image from NASA's Juno spacecraft. As with solar eclipses on the Earth, within the dark circle racing across Jupiter's cloud tops one would witness a full solar eclipse as Io passes in front of the Sun.

Such events occur frequently on Jupiter because it is a large planet with many moons. In addition, unlike most other planets in our solar system, Jupiter's axis is not highly tilted relative to its orbit, so the Sun never strays far from Jupiter's equatorial plane (+/- 3 degrees). This means Jupiter's moons regularly cast their shadows on the planet throughout its year.

Juno's close proximity to Jupiter provides an exceptional fish-eye view, showing a small fraction near the planet's equator. The shadow is about 3,600 kilometers (2,200 miles) wide, approximately the same width as Io, but appears much larger relative to Jupiter. A little larger than Earth's Moon, Io is perhaps most famous for its many active volcanoes, often caught lofting fountains of ejecta well above its thin atmosphere.

Image Credit: NASA/JPL-Caltech/SwRI/MSSS

Pluto's Blue Sky

Click on the image for higher resolution

Pluto's haze layer shows its blue color in this picture taken by the New Horizons Ralph/Multispectral Visible Imaging Camera (MVIC). The high-altitude haze is thought to be similar in nature to that seen at Saturn’s moon Titan. The source of both hazes likely involves sunlight-initiated chemical reactions of nitrogen and methane, leading to relatively small, soot-like particles (called tholins) that grow as they settle toward the surface. This image was generated by software that combines information from blue, red and near-infrared images to replicate the color a human eye would perceive as closely as possible.

Image Credit: NASA/JHUAPL/SwRI

Pluto in True Color

Click on the image for higher resolution

Four images from New Horizons' Long Range Reconnaissance Imager (LORRI) were combined with color data from the Ralph instrument to create this sharper global view of Pluto. (The lower right edge of Pluto in this view currently lacks high-resolution color coverage.) The images, taken when the spacecraft was 280,000 miles (450,000 kilometers) away from Pluto, show features as small as 1.4 miles (2.2 kilometers). That's twice the resolution of the single-image view captured on July 13 and revealed at the approximate time of New Horizons' July 14 closest approach.

Image Credit: NASA/JHUAPL/SwRI

Io as seen by the Galileo spacecraft

Click on the image for full resolution

Two sulfurous eruptions are visible on Jupiter's volcanic moon Io in this color composite image from the robotic Galileo spacecraft that orbited Jupiter from 1995 to 2003. At the image top, over Io's limb, a bluish plume rises about 140 kilometers above the surface of a volcanic caldera known as Pillan Patera. In the image middle, near the night/day shadow line, the ring shaped Prometheus plume is seen rising about 75 kilometers above Io while casting a shadow below the volcanic vent. Named for the Greek god who gave mortals fire, the Prometheus plume is visible in every image ever made of the region dating back to the Voyager flybys of 1979 - presenting the possibility that this plume has been continuously active for at least 18 years. This digitally sharpened image of Io was originally recorded in 1997 from a distance of about 600,000 kilometers. Recent analyses of Galileo data has uncovered evidence of a magma ocean beneath Io's surface.
Image Credit: Galileo Project, JPL, NASA
Image enhancement: Jean-Baptiste Faure

Mercury's horizon seen by MESSENGER spacecraft

Click on the image for full resolution

Another day, another beautiful view of Mercury's horizon. In this scene, which was acquired looking from the shadows toward the sunlit side of the planet, a 120-km (75 mi.) impact crater stands out near the center. Emanating from this unnamed crater are striking chains of secondary craters, which gouged linear tracks radially away from the crater. While this crater is not especially fresh (its rays have faded into the background), it does appear to have more prominent secondary crater chains than many of its peers. This image was acquired on Oct. 2, 2013 by the Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS) aboard NASA's MESSENGER spacecraft, as part of the MDIS's limb imaging campaign. Once per week, MDIS captures images of Mercury's limb, with an emphasis on imaging the southern hemisphere limb. These limb images provide information about Mercury's shape and complement measurements of topography made by the Mercury Laser Altimeter (MLA) of Mercury's northern hemisphere. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the solar system's innermost planet. During the first two years of orbital operations, MESSENGER acquired over 150,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015.
Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Apollo 11 - Earthrise over the Moon

Click on the image for full resolution (2.73 MB)

Earthrise over the Moon taken by the Apollo 11 crew.
The full resolution image weighs 2.73 MB, so please be patient when downloading!
Credit: NASA-Johnson Space Center
Image enhancement: Jean-Baptiste Faure

Mini Planetary System KOI-961 (Artist Concept)

Click on the image for full resolution

This artist's concept depicts an itsy bitsy planetary system - so compact, in fact, that it's more like Jupiter and its moons than a star and its planets. Astronomers using data from NASA's Kepler mission and ground-based telescopes recently confirmed that the system, called KOI-961, hosts the three smallest exoplanets known so far to orbit a star other than our sun. An exoplanet is a planet that resides outside of our solar system. The star, which is located about 130 light-years away in the Cygnus constellation, is what's called a red dwarf. It's one-sixth the size of the sun, or just 70 percent bigger than Jupiter. The star is also cooler than our sun, and gives off more red light than yellow. The smallest of the three planets, called KOI-961.03, is actually located the farthest from the star, and is pictured in the foreground. This planet is about the same size as Mars, with a radius only 0.57 times that of Earth. The next planet to the upper right is KOI-961.01, which is 0.78 times the radius of Earth. The planet closest to the star is KOI-961.02, with a radius 0.73 times the Earth's. All three planets whip around the star in less than two days, with the closest planet taking less than half a day. Their close proximity to the star also means they are scorching hot, with temperatures ranging from 350 to 836 degrees Fahrenheit (176 to 447 degrees Celsius). The star's habitable zone, or the region where liquid water could exist, is located far beyond the planets.
The ground-based observations contributing to these discoveries were made with the Palomar Observatory, near San Diego, Calif., and the W.M. Keck Observatory atop Mauna Kea in Hawaii. NASA's Ames Research Center in Moffett Field, Calif., manages Kepler's ground system development, mission operations and science data analysis. JPL managed the Kepler mission's development.
Credit: NASA/JPL-Caltech

High-resolution satellite image of the State of Hawaii

Click on the image for full resolution (1.0 MB)

High-resolution satellite image of the State of Hawaii.
The full resolution image weighs 1.0 MB, so please be (a little) patient when downloading!
Credit: NOAA

A view of Saturn and its Rings, Enceladus and Epimetheus!

Click on the image for full resolution

A pair of Saturn's moons appear insignificant compared to the immensity of the planet in this Cassini spacecraft view along the terminator where day transitions to night. The larger moon Enceladus (504 kilometers, or 313 miles across) is also on the left, just a bit closer to the center of the image. Epimetheus (113 kilometers, or 70 miles across) appears as a tiny black speck on the far left of the image, left of Enceladus, just below the thin line of the rings. The rings cast wide shadows on the southern hemisphere of the planet. This view looks toward the northern, sunlit side of the rings from just above the ringplane. The image was taken with the Cassini spacecraft wide-angle camera on Nov. 4, 2011 using a spectral filter sensitive to wavelengths of near-infrared light centered at 752 nanometers. The view was acquired at a distance of approximately 1.2 million kilometers (746,000 miles) from Saturn and roughly 1 million kilometers (600,000 miles) from Enceladus and Epimetheus. Image scale is about 75 kilometers (47 miles) per pixel on Saturn, 60 kilometers (37 miles) per pixel on Enceladus and 66 kilometers (41 miles) per pixel on Epimetheus.
Credit: NASA/JPL-Caltech/Space Science Institute

Dramatic Voyager 1 view of Jupiter's Great Red Spot

Click on the image to enlarge

This dramatic view of Jupiter's Great Red Spot and its surroundings was obtained by Voyager 1 on Feb. 25, 1979, when the spacecraft was 9.2 million kilometers (5.7 million miles) from Jupiter. Cloud details as small as 160 kilometers (100 miles) across can be seen here. The colorful, wavy cloud pattern to the left of the Red Spot is a region of extraordinarily complex end variable wave motion. The Jet Propulsion Laboratory manages the Voyager mission for NASA's Office of Space Science.
Credit: NASA/JPL

Saturn's geyser moon Enceladus as seen by NASA's Cassini

Click on the image for full resolution

NASA's Cassini spacecraft successfully completed its Oct. 1 flyby of Saturn's moon Enceladus and its jets of water vapor and ice. At its closest approach, the spacecraft flew approximately 62 miles (100 kilometers) above the moon's surface. The close approach was designed to give some of Cassini's instruments, including the ion and neutral mass spectrometer, the chance to "taste" the jets themselves. At a higher vantage point during the encounter, Cassini's high-resolution camera captured pictures of the jets emanating from the moon's south polar region. The images of the surface include previously seen leading-hemisphere terrain. However, during this encounter, multi-spectral imaging of these terrains extended farther into the ultraviolet region of the electromagnetic spectrum than had previously been achieved at this resolution. By looking at the surface at ultraviolet wavelengths, scientists can better detect the difference between surface materials and shadows than they can at visible wavelengths, where icy materials are highly reflective and shadows are washed out. With both ultraviolet and visible images of the same terrain available to them, scientists will better understand how the surface coverage of icy particles coming from the vents and plumes changes with terrain type and age. Cassini's next pass of this fascinating moon will be Oct. 19, when the spacecraft flies by at an altitude of approximately 765 miles (1231 kilometers).
Credit: NASA/JPL-Caltech/Space Science Institute