Nasa Image of the Day
Watching the Aurora From Orbit

Watching the Aurora From Orbit

Expedition 52 Flight Engineer Jack Fischer of NASA shared photos and time-lapse video of a glowing green aurora seen from his vantage point 250 miles up, aboard the International Space Station. This aurora photo was taken on June 26, 2017.

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Sky View Cafe
Sky View Cafe

Sky View Café is a Java applet that lets you use your web browser to see many types of astronomical information, in both graphical and numerical form. You can see which stars and planets will be out tonight in the sky above your home town, see how the next solar or lunar eclipse will look from London, or find out when the Moon rose over Sydney on your birthday ten years ago. Sky View Café includes star charts, a 3-D orrery, displays of the moons of Jupiter and Saturn, an astronomical event calendar, an ephemeris generator, and many other features. Enter Sky View Café now!

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The Sky Tonight Astronomy News
Saturn surprises - Read more >
Mon, 24 Jul 2017 16:37:00 +0200


New views from Cassini’s weekly dives between Saturn and its rings



Virtual Universe - Read more >
Mon, 24 Jul 2017 09:25:00 +0200


Space Science Image of the Week: Record-breaking simulation reproduces large-scale structure of the Universe to prepare for Euclid mission



NASA's Hubble Sees Martian Moon Orbiting the Red Planet
Thu, 20 Jul 2017 13:00:00 EDTHubble Image

The Tiny Moon Phobos Is Photographed During Its Quick Trip Around Mars

While photographing Mars, NASA’s Hubble Space Telescope captured a cameo appearance of the tiny moon Phobos on its trek around the Red Planet. Discovered in 1877, the diminutive, potato-shaped moon is so small that it appears star-like in the Hubble pictures. Phobos orbits Mars in just 7 hours and 39 minutes, which is faster than Mars rotates. The moon’s orbit is very slowly shrinking, meaning it will eventually shatter under Mars’ gravitational pull, or crash into the planet. Hubble took 13 separate exposures over 22 minutes to create a time-lapse video showing the moon’s orbital path.



Last command - Read more >
Tue, 18 Jul 2017 13:28:00 +0200


LISA Pathfinder principal investigator Stefano Vitale sends the final command to the spacecraft, shutting it down after successfully demonstrating the technology to build ESA's future gravitational wave observatory



Tributes to wetter times on Mars - Read more >
Thu, 13 Jul 2017 11:00:00 +0200


A dried-out river valley with numerous tributaries is seen in this recent view of the Red Planet captured by ESA’s Mars Express.




Hubble Pushed Beyond Limits to Spot Clumps of New Stars in Distant Galaxy
Thu, 06 Jul 2017 13:00:00 EDTHubble Image

Gravitational lens helps reveal "fireworks" in the early universe

When the universe was young, stars formed at a much higher rate than they do today. By peering across billions of light-years of space, Hubble can study this early era. But at such distances, galaxies shrink to smudges that hide key details. Astronomers have teased out those details in one distant galaxy by combining Hubble’s sharp vision with the natural magnifying power of a gravitational lens. The result is an image 10 times better than what Hubble could achieve on its own, showing dense clusters of brilliant, young stars that resemble cosmic fireworks.



Preparing for Mercury: BepiColombo stack completes testing - Read more >
Thu, 06 Jul 2017 13:00:00 +0200


ESA’s Mercury spacecraft has passed its final test in launch configuration, the last time it will be stacked like this before being reassembled at the launch site next year.




BepiColombo live - Read more >
Tue, 04 Jul 2017 15:20:00 +0200


Replay of Thursday's media briefing on our mission to Mercury



Artificial brain helps Gaia catch speeding stars - Read more >
Mon, 26 Jun 2017 10:00:00 +0200


With the help of software that mimics a human brain, ESA’s Gaia satellite spotted six stars zipping at high speed from the centre of our Galaxy to its outskirts. This could provide key information about some of the most obscure regions of the Milky Way. 




Hubble Captures Massive Dead Disk Galaxy that Challenges Theories of Galaxy Evolution
Wed, 21 Jun 2017 13:00:00 EDTHubble Image

Young, Dead, Compact, Disk Galaxy Surprises Astronomers, Offers New Clues to How Modern-Day Elliptical Galaxies Formed

Astronomers combined the power of a “natural lens” in space with the capability of NASA’s Hubble Space Telescope to make a surprising discovery—the first example of a compact yet massive, fast-spinning, disk-shaped galaxy that stopped making stars only a few billion years after the big bang. Researchers say that finding such a galaxy so early in the history of the universe challenges the current understanding of how massive galaxies form and evolve. Astronomers expected to see a chaotic ball of stars formed through galaxies merging together. Instead, they saw evidence that the stars were born in a pancake-shaped disk. The galaxy, called MACS 2129-1, is considered “dead” because it is no longer making stars. This new insight is forcing astronomers to rethink their theories of how galaxies burn out early on and evolve into local elliptical-shaped galaxies. “Perhaps we have been blind to the fact that early ‘dead’ galaxies could in fact be disks, simply because we haven’t been able to resolve them,” said study leader Sune Toft of the Dark Cosmology Center at the Niels Bohr Institute, University of Copenhagen.



Gravitational wave mission selected, planet-hunting mission moves forward - Read more >
Tue, 20 Jun 2017 16:30:00 +0200


The LISA trio of satellites to detect gravitational waves from space has been selected as the third large-class mission in ESA’s Science programme, while the Plato exoplanet hunter moves into development.






Call for media: Last chance to view ESA’s Mercury Explorer BepiColombo - Read more >
Wed, 14 Jun 2017 18:00:00 +0200


Media representatives are invited to a briefing on BepiColombo, ESA and JAXA’s joint mission to Mercury, and to view the spacecraft before it leaves for Europe’s Spaceport in Kourou, French Guiana, for launch next year.  




The future of the Orion constellation - Read more >
Fri, 09 Jun 2017 11:00:00 +0200


A new video, based on measurements by ESA’s Gaia and Hipparcos satellites, shows how our view of the Orion constellation will evolve over the next 450 000 years.




Window to a watery past on Mars - Read more >
Thu, 08 Jun 2017 11:00:00 +0200


This 70 km-wide crater and its surrounds offer a window into the watery past of the Red Planet.




Hubble Astronomers Develop a New Use for a Century-Old Relativity Experiment to Measure a White Dwarf's Mass
Wed, 07 Jun 2017 11:15:00 EDTHubble Image

White dwarf shows how gravity can bend starlight

Albert Einstein reshaped our understanding of the fabric of space. In his general theory of relativity in 1915, he proposed the revolutionary idea that massive objects warp space, due to the effects of gravity. Until that time, Isaac Newton's theory of gravity from two centuries earlier held sway: that space was unchanging. Einstein's theory was experimentally verified four years later when a team led by British astronomer Sir Arthur Eddington measured how much the sun's gravity deflected the image of a background star as its light grazed the sun during a solar eclipse. Astronomers had to wait a century, however, to build telescopes powerful enough to detect this gravitational warping phenomenon caused by a star outside our solar system. The amount of deflection is so small only the sharpness of the Hubble Space Telescope could measure it.

Hubble observed the nearby white dwarf star Stein 2051 B as it passed in front of a background star. During the close alignment, the white dwarf's gravity bent the light from the distant star, making it appear offset by about 2 milliarcseconds from its actual position. This deviation is so small that it is equivalent to observing an ant crawl across the surface of a quarter from 1,500 miles away.



Jackpot! Cosmic Magnifying-Glass Effect Captures Universe's Brightest Galaxies
Tue, 06 Jun 2017 15:15:00 EDTHubble Image

Galaxies Shine with the Brilliance of up to 100 Trillion Suns

Astronomers were fascinated in the 1980s with the discovery of nearby dust-enshrouded galaxies that glowed thousands of times brighter than our Milky Way galaxy in infrared light. Dubbed ultra-luminous infrared galaxies, they were star-making factories, churning out a prodigious amount of stars every year. What wasn't initially clear was what powered these giant infrared light bulbs. Observations by the Hubble Space Telescope helped astronomers confirm the source of the galaxies' light output. Many of them reside within "nests" of galaxies engaged in multiple pile-ups of three, four or even five galaxies. The dust is produced by the firestorm of star birth, which glows fiercely in infrared light.

Now Hubble is illuminating the bright galaxies' distant dust-enshrouded cousins. Boosted by natural magnifying lenses in space, Hubble has captured unique close-up views of the universe's brightest infrared galaxies. The galaxies are ablaze with runaway star formation, pumping out more than 10,000 new stars a year. This unusually rapid star birth is occurring at the peak of the universe's star-making boom more than 8 billion years ago. The star-birth frenzy creates lots of dust, which enshrouds the galaxies, making them too faint to detect in visible light. But they glow fiercely in infrared light, shining with the brilliance of 10 trillion to 100 trillion suns.

The galaxy images, magnified through a phenomenon called gravitational lensing, reveal a tangled web of misshapen objects punctuated by exotic patterns such as rings and arcs. The odd shapes are due largely to the foreground lensing galaxies' powerful gravity distorting the images of the background galaxies. Two possibilities for the star-making frenzy are galaxy collisions or gas spilling into the galaxies.



Mini-Flares Potentially Jeopardize Habitability of Planets Circling Red Dwarf Stars
Tue, 06 Jun 2017 11:15:00 EDTHubble Image

Solar flares and associated eruptions can trigger auroras on Earth or, more ominously, damage satellites and power grids. Could flares on cool, red dwarf stars cause even more havoc to orbiting planets, even rendering them uninhabitable? To help answer that question, astronomers sought to find out how many flares such stars typically unleash.

A new study of archival ultraviolet observations from the Galaxy Evolution Explorer (GALEX) spacecraft detected dozens of flares from red dwarf stars. Some flares were weaker than any previously detected. Since smaller flares tend to occur more frequently, these tiny flares might have big implications for planetary habitability.



Hubble's Tale of Two Exoplanets: Nature vs. Nurture
Mon, 05 Jun 2017 15:15:00 EDTHubble Image

Atmospheres of Two Hot Jupiters: Cloudy and Clear

Astronomers once thought that the family of planets that orbit our sun were typical of what would eventually be found around other stars: a grouping of small rocky planets like Earth huddled close to their parent star, and an outer family of monstrous gaseous planets like Jupiter and Saturn.

But ever since the discovery of the first planet around another star (or exoplanet) the universe looks a bit more complicated — if not downright capricious. There is an entire class of exoplanets called "hot Jupiters." They formed like Jupiter did, in the frigid outer reaches of their planetary system, but then changed Zip code! They migrated inward to be so close to their star that temperatures are well over 1,000 degrees Fahrenheit.

Astronomers would like to understand the weather on these hot Jupiters and must tease out atmospheric conditions by analyzing how starlight filters through a planet's atmosphere. If the spectral fingerprint of water can be found, then astronomers conclude the planet must have relatively clear skies that lets them see deep into the atmosphere. If the spectrum doesn't have any such telltale fingerprints, then the planet is bland-looking with a high cloud deck.

Knowing the atmospheres on these distant worlds yields clues to how they formed and evolved around their parent star. In a unique experiment, astronomers aimed the Hubble Space Telescope at two "cousin" hot Jupiters that are similar in several respects. However, the researchers were surprised to learn that one planet is very cloudy, and the other has clear skies.



More to planets than meets the eye - Read more >
Thu, 01 Jun 2017 16:45:00 +0200


In ESA’s first event of its kind, members of the public have been invited to touch, taste and hear about life in the Universe in an immersive day of activities that are suitable for the sensory impaired. 




Collapsing Star Gives Birth to a Black Hole
Thu, 25 May 2017 13:00:00 EDTHubble Image

Massive Dying Star Goes Out With a Whimper Instead of a Bang

Every second a star somewhere out in the universe explodes as a supernova. But some super-massive stars go out with a whimper instead of a bang. When they do, they can collapse under the crushing tug of gravity and vanish out of sight, only to leave behind a black hole. The doomed star, named N6946-BH1, was 25 times as massive as our sun. It began to brighten weakly in 2009. But, by 2015, it appeared to have winked out of existence. By a careful process of elimination, based on observations by the Large Binocular Telescope and the Hubble and Spitzer space telescopes, the researchers eventually concluded that the star must have become a black hole. This may be the fate for extremely massive stars in the universe.



Schiaparelli landing investigation completed - Read more >
Wed, 24 May 2017 15:00:00 +0200


The inquiry into the crash-landing of the ExoMars Schiaparelli module has concluded that conflicting information in the onboard computer caused the descent sequence to end prematurely.




Hubble Spots Moon Around Third Largest Dwarf Planet
Thu, 18 May 2017 13:00:00 EDTHubble Image

Most of the dwarf planets now have known moons

Beyond the orbit of Neptune lies a frigid, dark, vast frontier of countless icy bodies left over from the solar system's construction 4.6 billion years ago. This region, called the Kuiper Belt, was hypothesized by astronomer Gerard Kuiper in 1951. But it took another four decades for astronomers to confirm its existence. The largest bodies are called dwarf planets, with Pluto being the biggest member. Pluto is so big, in fact, that it was discovered 60 years before other Kuiper worlds were detected. Moons around dwarf planets are elusive, though. Pluto's moon Charon wasn't found until the mid-1970s.

Now, astronomers have uncovered a moon around another dwarf planet by using the combined power of three space observatories, including archival images from the Hubble Space Telescope. Called 2007 OR10, it is the third-largest dwarf planet in the Kuiper Belt. With this moon's discovery, most of the known dwarf planets in the Kuiper Belt larger than 600 miles across have companions. These bodies provide insight into how moons formed in the young solar system. In fact, there is an emerging view that collisions between planetary bodies can result in the formation of moons. Based on moon rock samples from NASA's Apollo mission, astronomers believe that Earth's only natural satellite was born out of a collision with a Mars-sized object 4.4 billion years ago.



Observatories Combine to Crack Open the Crab Nebula
Wed, 10 May 2017 13:00:00 EDTHubble Image

Colorful New Portrait Shows Energetic Details Embedded in Supernova Remnant
In the summer of the year 1054 AD, Chinese astronomers saw a new "guest star," that appeared six times brighter than Venus. So bright in fact, it could be seen during the daytime for several months. Halfway around the world, Native Americans made pictographs of a crescent moon with the bright star nearby that some think may also have been a record of the supernova.

This "guest star" was forgotten about until 700 years later with the advent of telescopes. Astronomers saw a tentacle-like nebula in the place of the vanished star and called it the Crab Nebula. Today we know it as the expanding gaseous remnant from a star that self-detonated as a supernova, briefly shining as brightly as 400 million suns. The explosion took place 6,500 light-years away. If the blast had instead happened 50 light-years away it would have irradiated Earth, wiping out most life forms.

In the late 1960s astronomers discovered the crushed heart of the doomed star, an ultra-dense neutron star that is a dynamo of intense magnetic field and radiation energizing the nebula. Astronomers therefore need to study the Crab Nebula across a broad range of electromagnetic radiation, from X-rays to radio waves. This composite picture from five observatories captures the complexity of this tortured-looking supernova remnant.



A Lot of Galaxies Need Guarding in This NASA Hubble View
Thu, 04 May 2017 10:00:00 EDTHubble Image

Power of Massive Galaxy Cluster Harnessed to Probe Remote Galaxies in Early Universe
Like the quirky characters in the upcoming film Guardians of the Galaxy Vol. 2, NASA's Hubble Space Telescope has some amazing superpowers, specifically when it comes to observing galaxies across time and space. One stunning example is galaxy cluster Abell 370, which contains a vast assortment of several hundred galaxies tied together by the mutual pull of gravity. That's a lot of galaxies to be guarding, and just in this one cluster! Photographed in a combination of visible and near-infrared light, the immense cluster is a rich mix of galaxy shapes. Entangled among the galaxies are mysterious-looking arcs of blue light. These are actually distorted images of remote galaxies behind the cluster. These far-flung galaxies are too faint for Hubble to see directly. Instead, the gravity of the cluster acts as a huge lens in space, magnifying and stretching images of background galaxies like a funhouse mirror. Abell 370 is located approximately 4 billion light-years away in the constellation Cetus, the Sea Monster. It is the last of six galaxy clusters imaged in the recently concluded Frontier Fields project — an ambitious, community-developed collaboration among NASA's Great Observatories and other telescopes that harnessed the power of massive galaxy clusters and probed the earliest stages of galaxy development.



Countdown to Cassini's Grand Finale - Read more >
Tue, 25 Apr 2017 15:30:00 +0200


After nearly 13 years in orbit around Saturn, the international Cassini–Huygens mission is about to begin its final chapter: the spacecraft will perform a series of daring dives between the planet and its rings, leading to a dramatic final plunge into Saturn's atmosphere on 15 September. 




A New Angle on Two Spiral Galaxies for Hubble's 27th Birthday
Thu, 20 Apr 2017 10:00:00 EDTHubble Image

Hubble Celebrates Its Anniversary with a Spectacular Pair of Galaxies

When the Hubble Space Telescope launched aboard the Space Shuttle Discovery on April 24, 1990, astronomers could only dream what they might see. Now, 27 years and more than a million observations later, the telescope delivers yet another magnificent view of the universe — this time, a striking pair of spiral galaxies much like our own Milky Way. These island cities of stars, which are approximately 55 million light-years away, give astronomers an idea of what our own galaxy would look like to an outside observer. The edge-on galaxy is called NGC 4302, and the tilted galaxy is NGC 4298. Although the pinwheel galaxies look quite different because they are angled at different positions on the sky, they are actually very similar in terms of their structure and contents.



Hubble Spots Possible Venting Activity on Europa
Thu, 13 Apr 2017 14:00:00 EDTHubble Image

Best Evidence Yet for Reoccurring Water Vapor Plumes Erupting from Jupiter’s Moon
When Galileo discovered Jupiter's moon Europa in 1610, along with three other satellites whirling around the giant planet, he could have barely imagined it was such a world of wonder.

This revelation didn't happen until 1979, when NASA's Voyager 1 and 2 flew by Jupiter and found evidence that Europa's interior, encapsulated under a crust of ice, has been kept warm over billions of years. The warmer temperature is due to gravitational tidal forces that flex the moon's interior — like squeezing a rubber ball — keeping it warm. At the time, one mission scientist even speculated that the Voyagers might catch a snapshot of geysers on Europa.

Such activity turned out to be so elusive that astronomers had to wait over three decades for the peering eye of Hubble to monitor the moon for signs of venting activity. A newly discovered plume seen towering 62 miles above the surface in 2016 is at precisely the same location as a similar plume seen on the moon two years earlier by Hubble. These observations bolster evidence that the plumes are a real phenomenon, flaring up intermittently in the same region on the satellite.

The location of the plumes corresponds to the position of an unusually warm spot on the moon's icy crust, as measured in the late 1990s by NASA's Galileo spacecraft. Researchers speculate that this might be circumstantial evidence for material venting from the moon's subsurface. The material could be associated with the global ocean that is believed to be present beneath the frozen crust. The plumes offer an opportunity to sample what might be in the ocean, in the search for life on that distant moon.



Hubble Takes Close-up Portrait of Jupiter
Thu, 06 Apr 2017 13:00:00 EDTHubble Image

Majestic Giant Planet is a Swirl of Colorful Clouds
Named after the Roman king of the gods, the immense planet Jupiter is undoubtedly king of the solar system. Containing more mass than all the other planets combined, Jupiter's immense gravitational field deflects wayward comets that otherwise might slam into Earth, wreaking havoc.

This dazzling Hubble Space Telescope photo of Jupiter was taken when it was comparatively close to Earth, at a distance of 415 million miles. Hubble reveals the intricate, detailed beauty of Jupiter's clouds as arranged into bands of different latitudes, known as tropical regions. These bands are produced by air flowing in different directions at various latitudes. Lighter colored areas, called zones, are high-pressure where the atmosphere rises. Darker low-pressure regions where air falls are called belts. The planet's trademark, the Great Red Spot, is a long-lived storm roughly the diameter of Earth. Much smaller storms appear as white or brown-colored ovals. Such storms can last as little as a few hours or stretch on for centuries.



Exoplanet mission gets ticket to ride - Read more >
Thu, 06 Apr 2017 16:30:00 +0200


A Soyuz rocket operated by Arianespace from Europe’s spaceport in Kourou will boost ESA’s upcoming exoplanet satellite into space.




Crater triplets - Read more >
Thu, 06 Apr 2017 11:00:00 +0200


At first glance this scene may seem nothing out of the ordinary, but the large elongated crater marks the imprint of an impacting body that may have broken into three before it hit Mars.




Search For Stellar Survivor of a Supernova Explosion
Thu, 30 Mar 2017 13:00:00 EDTHubble Image

Star might answer question of how white dwarfs explode
Of all the varieties of exploding stars, the ones called Type Ia are perhaps the most intriguing. Their predictable brightness lets astronomers measure the expansion of the universe, which led to the discovery of dark energy. Yet the cause of these supernovae remains a mystery. Do they happen when two white dwarf stars collide? Or does a single white dwarf gorge on gases stolen from a companion star until bursting?

If the second theory is true, the normal star should survive. Astronomers used NASA's Hubble Space Telescope to search the gauzy remains of a Type Ia supernova in a neighboring galaxy called the Large Magellanic Cloud. They found a sun-like star that showed signs of being associated with the supernova. Further investigations will be needed to learn if this star is truly the culprit behind a white dwarf's fiery demise.



NASA Announces Astronomy and Astrophysics Fellows for 2017
Wed, 29 Mar 2017 13:00:00 EDTHubble Image

Some of the world's most exciting, young scientists to help NASA explore mysteries of the cosmos
NASA has selected 28 Fellows for its prestigious Einstein, Hubble, and Sagan fellowships. Each post-doctoral fellowship provides three years of support to awardees to pursue independent research in astronomy and astrophysics. The new Fellows will begin their programs in the fall of 2017 at a host university or research center of their choosing in the United States.



Final two ExoMars landing sites chosen - Read more >
Tue, 28 Mar 2017 17:00:00 +0200


Two ancient sites on Mars that hosted an abundance of water in the planet’s early history have been recommended as the final candidates for the landing site of the 2020 ExoMars rover and surface science platform: Oxia Planum and Mawrth Vallis.




Gravitational Wave Kicks Monster Black Hole Out Of Galactic Core
Thu, 23 Mar 2017 13:00:00 EDTHubble Image

Runaway black hole is the most massive ever detected far from its central home
Normally, hefty black holes anchor the centers of galaxies. So researchers were surprised to discover a supermassive black hole speeding through the galactic suburbs. Black holes cannot be observed directly, but they are the energy source at the heart of quasars — intense, compact gushers of radiation that can outshine an entire galaxy. NASA's Hubble Space Telescope made the discovery by finding a bright quasar located far from the center of the host galaxy.

Researchers estimate that it took the equivalent energy of 100 million supernovas exploding simultaneously to jettison the black hole. What could pry this giant monster from its central home? The most plausible explanation for this propulsive energy is that the monster object was given a kick by gravitational waves unleashed by the merger of two black holes as a result of a collision between two galaxies. First predicted by Albert Einstein, gravitational waves are ripples in the fabric of space that are created when two massive objects collide.



Before and after: unique changes spotted on Rosetta’s comet - Read more >
Tue, 21 Mar 2017 15:30:00 +0100


Growing fractures, collapsing cliffs, rolling boulders and moving material burying some features on the comet’s surface while exhuming others are among the remarkable changes documented during Rosetta’s mission.



This Month's Sky Map
This Month's Sky Map

Take a look at this month's Sky Map to help you explore the wonders of the night sky!

Ideal for all sky watchers including beginners to astronomy.

The Sky Map will help you identify planets, bright stars, constellations and nebulae!
Printable version available too!


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