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Tokyo, Kantō, Japan May 20, 2012 Image Credit: Itsuo Inouye/AP Photo

Mars digital-image mosaic merged with color of the MC-17 quadrangle, Phoenicis Lacus region of Mars. Two of the four largest shield volcanoes on Mars are within the northwestern part, the south half of Pavonis Mons and Arsia Mons. The eastern part includes Syria and Sinai Plana. Most of the quadrangle forms the Tharsis plateau--the highest plateau on Mars; its elevation, 10 km, is twice that of the Tibetan Plateau, the highest plateau on Earth. Also in the northeastern part is Noctis Labyrinthus, a complex system of fault valleys at the west end of Valles Marineris. The south-central part is marked by the large fault system, Claritas Fossae. Latitude range -30 to 0 degrees, longitude range 90 to 135 degrees. Image Credit: NASA/JPL/USGS Explanation from: http://photojournal.jpl.nasa.gov/catalog/pia00177

Kepler-10b is a scorched world, orbiting at a distance that's more than 20 times closer to its star than Mercury is to our own Sun. The daytime temperature's expected to be more than 2,500 degrees Fahrenheit, hotter than lava flows here on Earth. Intense radiation from the star has kept the planet from holding onto an atmosphere. Flecks of silicates and iron may be boiled off a molten surface and swept away by the stellar radiation, much like a comet's tail when its orbit brings it close to the Sun. Image Credit: NASA/Kepler Mission/Dana Berry Explanation from: https://www.nasa.gov/mission_pages/kepler/multimedia/images/kepler10_3.html

Ajo, Arizona. USA Image Credit & Copyright: Frank Zullo

This neat little galaxy is known as NGC 4526. Its dark lanes of dust and bright diffuse glow make the galaxy appear to hang like a halo in the emptiness of space in this new image from the NASA/ESA Hubble Space Telescope. Although this image paints a picture of serenity, the galaxy is anything but. It is one of the brightest lenticular galaxies known, a category that lies somewhere between spirals and ellipticals. It has hosted two known supernova explosions, one in 1969 and another in 1994, and is known to have a colossal supermassive black hole at its centre that has the mass of 450 million Suns. NGC 4526 is part of the Virgo cluster of galaxies. Ground-based observations of galaxies in this cluster have revealed that a quarter of these galaxies seem to have rapidly rotating discs of gas at their centres. The most spectacular of these is this galaxy, NGC 4526, whose spinning disc of gas, dust, and stars reaches out uniquely far from its heart, spanning some 7% of the galaxy's ent

Like a Dali masterpiece, this image of Messier 8 from the NASA/ESA Hubble Space Telescope is both intensely colourful and distinctly surreal. Located in the constellation of Sagittarius (The Archer), this giant cloud of glowing interstellar gas is a stellar nursery that is also known as the Lagoon Nebula. Although the name definitely suits the beauty of this object, “lagoon” does suggest tranquillity and there is nothing placid about the high-energy radiation causing these intricate clouds to glow. The massive stars hiding within the heart of the nebula give off enormous amounts of ultraviolet radiation, ionising the gas and causing it to shine colourfully, as well as sculpting the surrounding nebula into strange shapes. The result is an object around four to five thousand light-years away which, on a clear night, is faintly visible to the naked eye. Since it was first recorded back in the 1747 this object has been photographed and analysed at many different wavelengths. By using infra

Svalbard, Norway March 20, 2015 Image Credit & Copyright: David Jiménez

Some astronomical objects have endearing or quirky nicknames, inspired by mythology or their own appearance. Take, for example, the constellation of Orion (The Hunter), the Sombrero Galaxy, the Horsehead Nebula, or even the Milky Way. However, the vast majority of cosmic objects appear in astronomical catalogues, and are given rather less poetic names based on the order of their discovery. Two galaxies are clearly visible in this Hubble image, the larger of which is NGC 4424. This galaxy is catalogued in the New General Catalogue of Nebulae and lusters of Stars (NGC), which was compiled in 1888. The NGC is one of the largest astronomical catalogues, which is why so many Hubble Pictures of the Week feature NGC objects. In total there are 7840 entries in the catalogue and they are also generally the larger, brighter, and more eye-catching objects in the night sky, and hence the ones more easily spotted by early stargazers. The smaller, flatter, bright galaxy sitting just below NGC 4424 i

This artist's concept depicts the pulsar planet system discovered in 1992 using the Arecibo radio telescope in Puerto Rico. Three pulsar planets - the first of any kind ever found outside our Solar System - circling a pulsar called PSR B1257+12. Pulsars are rapidly rotating neutron stars, which are the collapsed cores of exploded massive stars. They spin and pulse with radiation, much like a lighthouse beacon. Here, the pulsar's twisted magnetic fields are highlighted by the blue glow. All three pulsar planets are shown in this picture; the farthest two from the pulsar (closest in this view) are about the size of Earth. Radiation from charged pulsar particles would probably rain down on the planets, causing their night skies to light up with auroras similar to our Northern Lights. One such aurora is illustrated on the planet at the bottom of the picture. Since this landmark discovery, more than 160 extrasolar planets have been observed around stars that are burning nuclear fuel

This enhanced-color image of Jupiter's south pole and its swirling atmosphere was created by citizen scientist Roman Tkachenko using data from the JunoCam imager on NASA's Juno spacecraft. Juno acquired the image, looking directly at the Jovian south pole, on February 2, 2017, at 6:06 a.m. PST (9:06 a.m. EST) from an altitude of about 63,400 miles (102,100 kilometers) above Jupiter's cloud tops. Cyclones swirl around the south pole, and white oval storms can be seen near the limb -- the apparent edge of the planet. Image Credit: NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko Explanation from: http://photojournal.jpl.nasa.gov/catalog/PIA21381

Villarrica, Chile March 3, 2015 Image Credit: Ariel Marinkovic

ISS, Orbit of the Earth September 2016 Image Credit: NASA/ESA

On March 28 at 03:42 UTC (1:42 p.m. AEST Queensland local time /Mar. 27 at 11:42 p.m. EST) NASA-NOAA's Suomi NPP satellite captured this visible image of Tropical Cyclone Debbie over eastern Australia. Before Debbie made landfall, NASA's Aqua satellite analyzed the temperatures in the storm on Mar. 27 at 0347 UTC (Mar. 26 at 11:47 pm. EST). The infrared imagery showed a large area of cloud top temperatures in thunderstorms around Debbie's eye as cold as near minus 63.1 degrees Celsius or minus 81.6 degrees Fahrenheit. Cloud top temperatures that cold have been shown to produce heavy rainfall. Cyclone Debbie made landfall north of Proserpine at Airlie Beach on March 28, shortly after noon AEST/Queensland local time (0200 UTC/March 27 at 10 p.m. EST). The Australian Bureau of Meteorology noted wind gusts stronger than 160 mph (260 kph) were recorded near landfall. The strong winds downed trees and powerlines. Power losses occurred in a large area between the towns of Bowen an

Artist’s impression of a galaxy forming stars within powerful outflows of material blasted out from supermassive black holes at its core. Results from ESO’s Very Large Telescope are the first confirmed observations of stars forming in this kind of extreme environment. The discovery has many consequences for understanding galaxy properties and evolution. Observations using ESO’s Very Large Telescope have revealed stars forming within powerful outflows of material blasted out from supermassive black holes at the cores of galaxies. These are the first confirmed observations of stars forming in this kind of extreme environment. The discovery has many consequences for understanding galaxy properties and evolution. The results are published in the journal Nature. A UK-led group of European astronomers used the MUSE and X-shooter instruments on the Very Large Telescope (VLT) at ESO’s Paranal Observatory in Chile to study an ongoing collision between two galaxies, known collectively as IRAS F2

ESO's Very Large Telescope (VLT) looks more like a very small telescope in this image! From this perspective, it is difficult to make out the silhouettes of the VLT’s four 8.2-metre Unit Telescopes, which sit atop Cerro Paranal in the Chilean Atacama Desert. The VLT’s location was very carefully selected. It is vital for the site to be as dry as possible, as water vapour can absorb infrared light and degrade observations. In order to reduce the effects of Earth’s atmosphere as far as possible, the VLT is at 2600 metres above sea level, minimising the amount of atmosphere sitting between it and the stars. Due to its remote location, Paranal manages to be mostly undisturbed and light-free. Even the winding roads that lead through the Atacama Desert to the observation site are dimly lit to avoid unnecessary light pollution. In this image, a trail of stars cuts across the the night sky like smoke rising from a celestial chimney. This is our home galaxy, the Milky Way. Towards the top o

A supermassive black hole inside a tiny galaxy is challenging scientists' ideas about what happens when two galaxies become one. Was 49 is the name of a system consisting of a large disk galaxy, referred to as Was 49a, merging with a much smaller "dwarf" galaxy called Was 49b. The dwarf galaxy rotates within the larger galaxy's disk, about 26,000 light-years from its center. Thanks to NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) mission, scientists have discovered that the dwarf galaxy is so luminous in high-energy X-rays, it must host a supermassive black hole much larger and more powerful than expected. "This is a completely unique system and runs contrary to what we understand of galaxy mergers," said Nathan Secrest, lead author of the study and postdoctoral fellow at the U.S. Naval Research Laboratory in Washington. Data from NuSTAR and the Sloan Digital Sky Survey suggest that the mass of the dwarf galaxy's black hole is huge, compared

Alaska, USA Image Credit: Michio Hoshino

This artist's representation shows the CoRoT-2 system, which is found about 880 light years from Earth. The system, which is estimated to be between 100 and 300 million years old, contains a star and a planet in close orbit around it. The separation between the star and the planet is only three percent of the distance between the Earth and the Sun, causing some exotic effects not seen in our solar system. The illustration shows the material, in blue, being stripped off the planet as X-rays from the star pummel the planet. A star is blasting a planet in its orbit with an extremely high level of X-rays. This high-energy radiation is eroding the planet at a rate of 5 million tons of material per second. The planet, in turn, may be speeding up the star's rotation, which keeps the star's magnetic fields very active. This graphic contains an image and illustration of a nearby star, named CoRoT-2a, which has a planet in close orbit around it. The separation between the star and pl

Svalbard, Norway March 20, 2015 Image Credit & Copyright: Miloslav Druckmüller

Not all spiral galaxies have to be picture-perfect to be striking. Messier 96, also known as NGC 3368, is a case in point: its core is displaced from the centre, its gas and dust are distributed asymmetrically and its spiral arms are ill-defined. But this portrait, taken with the FORS1 instrument on ESO’s Very Large Telescope, shows that imperfection is beauty in Messier 96. The galaxy's core is compact but glowing, and the dark dust lanes around it move in a delicate swirl towards the nucleus. And the spiral arms, patchy rings of young blue stars, are like necklaces of blue pearls. Messier 96 lies in the constellation of Leo (The Lion). It is the largest galaxy in the Leo I group of galaxies; including its outermost spiral arms, it spans some 100 000 light-years in diameter — about the size of our Milky Way. Its graceful imperfections likely result from the gravitational pull of other members in the group, or are perhaps due to past galactic encounters. A multitude of background g

The galaxy 3C186, located about 8 billion years from Earth, is most likely the result of a merger of two galaxies. This is supported by arc-shaped tidal tails, usually produced by a gravitational tug between two colliding galaxies, identified by the scientists. The merger of the galaxies also led to a merger of the two supermassive black holes in their centres, and the resultant black hole was then kicked out of its parent galaxy by the gravitational waves created by the merger. The bright, star-like looking quasar can be seen in the centre of the image. Its former host galaxy is the faint, extended object behind it. An international team of astronomers using the NASA/ESA Hubble Space Telescope have uncovered a supermassive black hole that has been propelled out of the centre of the distant galaxy 3C186. The black hole was most likely ejected by the power of gravitational waves. This is the first time that astronomers found a supermassive black hole at such a large distance from its ho

Osorno, Los Lagos, Chile June 5, 2011 Image Credit: Claudio Santana

The Sun has been virtually spotless, as in no sunspots, over the past 11 days, a spotless stretch that we have not seen since the last solar minimum many years ago. The videos shows the past four days (March 14-17, 2017) with a combination of an extreme ultraviolet image blended with just the filtered Sun. If we just showed the filtered Sun with no spots for reference points, any viewer would have a hard time telling that the Sun was even rotating. The Sun is trending again towards the solar minimum period of its 11 year cycle, which is predicted to be around 2020. Image Credit: NASA/GSFC/Solar Dynamics Observatory Explanation from: http://photojournal.jpl.nasa.gov/catalog/PIA21569

This image, taken with the NASA/ESA Hubble Space Telescope, shows the supernova remnant SNR 0509-68.7, also known as N103B. N103B was a Type Ia supernova, located in the Large Magellanic Cloud — a neighbouring galaxy of the Milky Way. Owing to its relative proximity to Earth, astronomers observe the remnant to search for a potential stellar survivor of the explosion. This could shed more light on the exact mechanism behind type Ia supernovae. The actual supernova remnant is the irregular shaped dust cloud, close to the centre of the image. The gas in the lower half of the image and the dense concentration of stars in the lower left are the outskirts of the star cluster NGC 1850, which has been observed by Hubble in the past. Image Credit: ESA/Hubble, NASA Explanation from: https://www.spacetelescope.org/images/heic17xx-n103ba/

Adansonia grandidieri, sometimes known as Grandidier's baobab, is the biggest and most famous of Madagascar's six species of baobabs. This imposing and unusual tree is endemic to the island of Madagascar, where it is an endangered species threatened by the encroachment of agricultural land. Grandidier's baobabs have massive cylindrical trunks, up to three meters across, covered with smooth, reddish-grey bark. They can reach 25 to 30 m (82 to 98 ft) in height. At certain times of the year the flat-topped crowns bear bluish-green palmate leaves, dark brown floral buds or spectacular flowers with white petals. The large, dry fruits of the baobab contain kidney-shaped seeds within an edible pulp. This baobab occurs in south-western Madagascar between Lac Ihotry (near Morombe) and Bereboka. Grandidier's baobab used to inhabit dry, deciduous forest, especially near seasonal rivers or lakes. However, today it is mainly found in open, agricultural land or degraded scrubland. Th

This animation shows how the illumination of Ceres' northern hemisphere varies with the dwarf planet's axial tilt, or obliquity. In the first frame the northern hemisphere is shown when Ceres' obliquity is 2 degrees, which is the minimum tilt. Regions that remain in shadow are shown in blue. The illumination shown is for the northern solstice, which is when the north pole is most illuminated. The second frame shows the same scene when Ceres' obliquity is 12 degrees. More polar regions are illuminated (this view is also for the northern solstice). The area of the regions that remain in shadow, marked with blue dots, is much smaller. The third frame shows the same scene when Ceres' obliquity is 20 degrees, which is the maximum tilt. The red circles show the only two craters in this scene that still have permanently shadowed regions. The polar regions are much better illuminated at this high obliquity. Image Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA Explanation from: h

New NASA research reveals that the giant Martian shield volcano Arsia Mons produced one new lava flow at its summit every 1 to 3 million years during the final peak of activity. The last volcanic activity there ceased about 50 million years ago—around the time of Earth’s Cretaceous–Paleogene extinction, when large numbers of our planet’s plant and animal species (including dinosaurs) went extinct. Located just south of Mars’ equator, Arsia Mons is the southernmost member of a trio of broad, gently sloping shield volcanoes collectively known as Tharsis Montes. Arsia Mons was built up over billions of years, though the details of its lifecycle are still being worked out. The most recent volcanic activity is thought to have taken place in the caldera—the bowl-shaped depression at the top—where 29 volcanic vents have been identified. Until now, it’s been difficult to make a precise estimate of when this volcanic field was active. “We estimate that the peak activity for the volcanic field a

Some galaxies are harder to classify than others. Here, Hubble’s trusty Wide Field Camera 3 (WFC3) has captured a striking view of two interacting galaxies located some 60 million light-years away in the constellation of Leo (The Lion). The more diffuse and patchy blue glow covering the right side of the frame is known as NGC 3447 — sometimes NGC 3447B for clarity, as the name NGC 3447 can apply to the overall duo. The smaller clump to the upper left is known as NGC 3447A. The trouble with space is that it is, to state the obvious, really, really big. Astronomers have for hundreds of years been discovering and naming galaxies, stars, cosmic clouds and more. Unifying and regulating the conventions and classifications for everything ever observed is very difficult, especially when you get an ambiguous object like NGC 3447, which stubbornly defies easy categorisation. Overall, we know NGC 3447 comprises a couple of interacting galaxies, but we’re unsure what each looked like before they b

This image, taken by the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, shows glowing dust inside the protocluster NGC 6334I. Studying this star-forming cloud in the Cat’s Paw Nebula (NGC 6334) with both ALMA and the Submillimeter Array (SMA) in Hawaii astronomers could see that something dramatic had taken place, completely changing a stellar nursery over a surprisingly short period of time. It is known that young stars form inside protoclusters when pockets of gas become so dense that they begin to collapse under their own gravity. Over time, discs of dust and gas form around these nascent stars and funnel material onto their surfaces helping them grow. However, this new image from ALMA shows a massive protostar, nestled deep within this dust-filled stellar nursery, that is undergoing an intense growth spurt, most likely triggered by an avalanche of gas falling onto its surface. This new material feeding it is causing the protostar to shine nearly 100 times brighter th

This artist’s rendering shows the tidal disruption event named ASASSN-14li, where a star wandering too close to a 3-million-solar-mass black hole was torn apart. The debris gathered into an accretion disk around the black hole. New data from NASA's Swift satellite show that the initial formation of the disk was shaped by interactions among incoming and outgoing streams of tidal debris. Some 290 million years ago, a star much like the sun wandered too close to the central black hole of its galaxy. Intense tides tore the star apart, which produced an eruption of optical, ultraviolet and X-ray light that first reached Earth in 2014. Now, a team of scientists using observations from NASA's Swift satellite have mapped out how and where these different wavelengths were produced in the event, named ASASSN-14li, as the shattered star's debris circled the black hole. "We discovered brightness changes in X-rays that occurred about a month after similar changes were observed in v

Redondo Beach, California, USA November 14, 2016 Image Credit: David McNew

This image shows the swirling shape of galaxy NGC 2217, in the constellation of Canis Major (The Great Dog). In the central region of the galaxy is a distinctive bar of stars within an oval ring. Further out, a set of tightly wound spiral arms almost form a circular ring around the galaxy. NGC 2217 is therefore classified as a barred spiral galaxy, and its circular appearance indicates that we see it nearly face-on. The outer spiral arms have a bluish colour, indicating the presence of hot, luminous, young stars, born out of clouds of interstellar gas. The central bulge and bar are yellower in appearance, due to the presence of older stars. Dark streaks can also be seen in places against the galaxy’s arms and central bulge, where lanes of cosmic dust block out some of the starlight. The majority of spiral galaxies in the local Universe — including our own Milky Way — are thought to have a bar of some kind, and these structures play an important role in the development of a galaxy. They

Dracaena cinnabari, the Socotra dragon tree or dragon blood tree, is a dragon tree native to the Socotra archipelago, part of Yemen, located in the Arabian Sea. It is so called due to the red sap that the trees produce. The dragon blood tree has a unique and strange appearance, with an "upturned, densely packed crown having the shape of an uprightly held umbrella". This evergreen species is named after its dark red resin, which is known as "dragon's blood". Unlike most monocot plants, Dracaena displays secondary growth, D. cinnabari even has growth zones resembling tree rings found in dicot tree species. Along with other arborescent Dracaena species it has a distinctive growth habit called "dracoid habitus". Its leaves are found only at the end of its youngest branches; its leaves are all shed every 3 or 4 years before new leaves simultaneously mature. Branching tends to occur when the growth of the terminal bud is stopped, due to either flowering or t