Nasa Image of the Day
Hubble Spots Two Interacting Galaxies Defying Cosmic Convention

Hubble Spots Two Interacting Galaxies Defying Cosmic Convention

Hubble spots two interacting galaxies some 60 million light-years away in the constellation of Leo.

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Astronomy Photographer of the YearAstronomy Photographer of the Year has teamed up with to bring you the finest selection of astronomy related books at the best prices.

Browse through our bookstore and check out our fine selection of books from star charts and astrophotography to mathematical astronomy. We are sure you will find the book that best suits your needs.

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!

Buy A Star Gift - Name a star for any occasion, view it live on Google Sky
Universal Star Registry Certificate Star Naming Service
Name a star for yourself or for that special person as the perfect gift that will sparkle for a lifetime! Ideal for any occassion, birthdays, christenings, anniversaries and memorials. Reserve a place in the heavens for your loved ones

The Sky Tonight Astronomy News
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.

Collapsing cliff reveals comet’s interior - Read more >
Tue, 21 Mar 2017 15:30:00 +0100

Rosetta scientists have made the first compelling link between an outburst of dust and gas and the collapse of a prominent cliff, which also exposed the pristine, icy interior of the comet.  

Hubble Discovery of Runaway Star Yields Clues to Breakup of Multiple-Star System
Fri, 17 Mar 2017 13:00:00 EDTHubble Image

Star Is Missing Link to a System that Flew Apart Over 500 Years Ago
In the 1400s, two power struggles were taking place quadrillions of miles apart. In England, two rival branches of the royal House of Plantagenet were battling each other for control of the country's throne. And, in a nebula far, far away, a cluster of stars was waging a real-life star wars, with the stellar members battling each other for supremacy in the Orion Nebula. The gravitational tussle ended with the system breaking apart and at least three stars being ejected in different directions.

Astronomers spotted two of the speedy, wayward stars over the past few decades. They traced both stars back 540 years to the same location and suggested they were part of a now-defunct multiple-star system. But the duo's combined energy, which is propelling them outward, didn't add up. The researchers reasoned there must be at least one other culprit that robbed energy from the stellar toss-up. Now NASA's Hubble Space Telescope has helped astronomers find the final piece of the puzzle by nabbing a third runaway star, which was a member of the same system as the two previously known stars. The stars reside in a small region of young stars called the Kleinmann-Low Nebula, near the center of the vast Orion Nebula complex, located 1,300 light-years from Earth.

ESA’s Jupiter mission moves off the drawing board - Read more >
Thu, 16 Mar 2017 15:00:00 +0100

Demanding electric, magnetic and power requirements, harsh radiation, and strict planetary protection rules are some of the critical issues that had to be tackled in order to move ESA’s Jupiter Icy Moons Explorer – Juice – from the drawing board and into construction.

ExoMars: science checkout completed and aerobraking begins - Read more >
Thu, 16 Mar 2017 11:00:00 +0100

The ExoMars Trace Gas Orbiter has completed another set of important science calibration tests before a year of aerobraking gets underway.

Hubble Dates Black Hole’s Last Big Meal
Thu, 09 Mar 2017 13:00:00 ESTHubble Image

Energetic Event 'Burped' Billowing Plasma Bubbles 6 Million Years Ago
About 6 million years ago, when our very remote ancestors began to evolve away from chimpanzees, our Milky Way galaxy's hefty black hole was enjoying a sumptuous feast. It gulped down a huge clump of interstellar hydrogen.

Now, eons later, we see the result of the black hole feast. The black hole "burped" hot plasma that is now towering far above and below the plane of our galaxy. These invisible bubbles, weighing the equivalent of millions of suns, are called the Fermi Bubbles. Their energetic gamma-ray glow was first discovered in 2010 by NASA's Fermi Gamma-ray Space Telescope. (Enrico Fermi was an Italian physicist who created the world's first nuclear reactor.)

Astronomers have wondered how long ago the gaseous lobes were created, and if the process was slow or rapid. Hubble observations of the northern bubble have solved the question by determining a more precise age for the bubbles. Hubble was used to measure the speed of the gasses in the billowing bubbles, and astronomers could then calculate back to the time when they were born in a fast, energetic event.

Remnants of a mega-flood on Mars - Read more >
Thu, 02 Mar 2017 11:00:00 +0100

ESA’s Mars Express has captured images of one of the largest outflow channel networks on the Red Planet.

Rapid changes point to origin of ultra-fast black hole winds - Read more >
Wed, 01 Mar 2017 19:00:00 +0100

ESA and NASA space telescopes have made the most detailed observation of an ultra-fast wind flowing from the vicinity of a black hole at nearly a quarter of the speed of light.

The 20th Anniversary of the Hubble Space Telescope's STIS Instrument
Tue, 28 Feb 2017 13:00:00 ESTHubble Image

The Versatile Space Telescope Imaging Spectrograph (STIS) Opens New Vistas in Astronomy
Twenty years ago, astronauts on the second servicing mission to the Hubble Space Telescope installed the Space Telescope Imaging Spectrograph (STIS) aboard Hubble. This pioneering instrument combines a camera with a spectrograph, which provides a "fingerprint" of a celestial object's temperature, chemical composition, density, and motion. STIS also reveals changes in the evolving universe and leads the way in the field of high-contrast imaging. The versatile instrument is sensitive to a wide range of wavelengths of light, from ultraviolet through the optical and into the near-infrared. From studying black holes, monster stars, and the intergalactic medium, to analyzing the atmospheres of worlds around other stars, STIS continues its epic mission to explore the universe.

Science checkout continues for ExoMars orbiter - Read more >
Mon, 27 Feb 2017 16:00:00 +0100

Next week, the ExoMars orbiter will devote two days to making important calibration measurements at the Red Planet, which are needed for the science phase of the mission that will begin next year.

The Dawn of a New Era for Supernova 1987A
Fri, 24 Feb 2017 10:00:00 ESTHubble Image

In February 1987, on a mountaintop in Chile, telescope operator Oscar Duhalde stood outside the observatory at Las Campanas and looked up at the clear night sky. There, in a hazy-looking patch of brightness in the sky — the Large Magellanic Cloud (LMC), a neighboring galaxy - was a bright star he hadn't noticed before.

That same night, Canadian astronomer Ian Shelton was at Las Campanas observing stars in the Large Magellanic Cloud. As Shelton was studying a photographic plate of the LMC later that night, he noticed a bright object that he initially thought was a defect in the plate. When he showed the plate to other astronomers at the observatory, he realized the object was the light from a supernova. Duhalde announced that he saw the object too in the night sky. The object turned out to be Supernova 1987A, the closest exploding star observed in 400 years. Shelton had to notify the astronomical community of his discovery. There was no Internet in 1987, so the astronomer scrambled down the mountain to the nearest town and sent a message to the International Astronomical Union's Bureau for Astronomical Telegrams, a clearing house for announcing astronomical discoveries.

Since that finding, an armada of telescopes, including the Hubble Space Telescope, has studied the supernova. Hubble wasn't even in space when SN 1987A was found. The supernova, however, was one of the first objects Hubble observed after its launch in 1990. Hubble has continued to monitor the exploded star for nearly 30 years, yielding insight into the messy aftermath of a star's violent self-destruction. Hubble has given astronomers a ring-side seat to watch the brightening of a ring around the dead star as the supernova blast wave slammed into it.

NASA Telescope Reveals Largest Batch of Earth-Size, Habitable-Zone Planets Around Single Star
Wed, 22 Feb 2017 13:00:00 ESTHubble Image

NASA's Spitzer Space Telescope has revealed the first known system of seven Earth-size planets around a single star. Three of these planets are located in an area called the habitable zone, where liquid water is most likely to thrive on a rocky planet. The system sets a new record for the greatest number of habitable zone planets found outside our solar system. Any of these seven planets could have liquid water, the key to life as we know it. The exoplanet system is called TRAPPIST-1 and is only 40 light-years away. Following up on the Spitzer discovery, NASA's Hubble Space Telescope has initiated the screening of four of the planets, including the three inside the habitable zone. These observations aim at assessing the presence of puffy, hydrogen-dominated atmospheres, typical for gaseous worlds like Neptune, around these planets. In May 2016, the Hubble team observed the two innermost planets and found no evidence for such puffy atmospheres. This finding strengthened the case that the planets closest to the star are terrestrial in nature. Astronomers plan follow-up studies using NASA's upcoming James Webb Space Telescope, scheduled to launch in 2018. With much greater sensitivity, Webb will be able to detect the chemical fingerprints of water, methane, oxygen, ozone, and other components of a planet's atmosphere. Webb also will analyze planets' temperatures and surface pressures — key factors in assessing their habitability.

For illustrations and more information about the TRAPPIST-1 system, visit:

The brightest, furthest pulsar in the Universe - Read more >
Tue, 21 Feb 2017 08:30:00 +0100

ESA’s XMM-Newton has found a pulsar – the spinning remains of a once-massive star – that is a thousand times brighter than previously thought possible.

Hubble Witnesses Massive Comet-Like Object Pollute Atmosphere of a White Dwarf
Thu, 09 Feb 2017 10:00:00 ESTHubble Image

Astronomers have found the best evidence yet of the remains of a comet-like object scattered around a burned-out star. They used NASA's Hubble Space Telescope to detect the debris, which has polluted the atmosphere of a compact star known as a white dwarf. The icy object, which has been ripped apart, is similar to Halley's Comet in chemical composition, but it is 100,000 times more massive and has a much higher amount of water. It is also rich in the elements essential for life, including nitrogen, carbon, oxygen, and sulfur. These findings are evidence for a belt of comet-like bodies similar to our solar system's Kuiper Belt orbiting the white dwarf. This is the first evidence of comet-like material polluting a white dwarf's atmosphere. The results also suggest the presence of unseen, surviving planets around the burned-out star.

Angling up for Mars science - Read more >
Tue, 07 Feb 2017 15:01:00 +0100

ESA’s latest Mars orbiter has moved itself into a new path on its way to achieving the final orbit for probing the Red Planet.

Swirling spirals at the north pole of Mars - Read more >
Thu, 02 Feb 2017 11:00:00 +0100

A new mosaic from ESA’s Mars Express shows off the Red Planet’s north polar ice cap and its distinctive dark spiralling troughs.

Dr. Margaret Meixner and Dr. Marc Postman Promoted to STScI Distinguished Astronomers
Tue, 24 Jan 2017 11:00:00 ESTHubble Image

The Space Telescope Science Institute (STScI) in Baltimore, Maryland, has appointed Dr. Margaret Meixner and Dr. Marc Postman to the position of STScI Distinguished Astronomer. Distinguished Astronomer is the highest level of appointment on the tenure track at STScI and represents a rank commensurate with the highest level of professorial appointments at major universities.

Meixner's promotion recognizes her long-term contributions to research and service at STScI. She has led international teams to study the life cycle of dust in the Magellanic Clouds using the Hubble, Spitzer and Herschel space telescopes. Postman is being recognized for his long-term contributions to the study of the formation and evolution of galaxies and clusters of galaxies. He has led important research to determine how the environments of galaxies determine their shapes and how the most massive galaxies evolve.

'Our Place In Space:' Astronomy and Art Combine in Brand New Hubble-Inspired Exhibition
Fri, 20 Jan 2017 09:00:00 ESTHubble Image

Since the dawn of civilization, we have gazed into the night sky and attempted to make sense of what we saw there, asking questions such as: Where do we come from? What is our place in the universe? And are we alone? As we ask those questions today and new technology expands our horizons further into space, our yearning for their answers only grows. Since its launch in 1990, NASA's Hubble Space Telescope has continued this quest for answers while orbiting Earth every 90 minutes. Hubble has not only made countless new astronomical discoveries, but also brought astronomy to the public eye, satisfying our curiosity, sparking our imaginations, and greatly impacting culture, society, and art.

A new traveling exhibition, "Our Place in Space" features iconic Hubble images. It presents not only a breathtaking pictorial journey through our solar system and to the edges of the known universe, but also Hubble-inspired works by selected Italian artists. By seamlessly integrating perspectives from both artists and astronomers, the exhibition will inspire visitors to think deeply about how humanity fits into the grand scheme of the universe. Before moving to other venues, the exhibition will be on display from February 1 to April 17, 2017, in the Istituto Veneto di Science, Lettere ed Arti, Palazzo Cavalli Franchetti, on the banks of the Grand Canal in Venice, Italy. For more information about the traveling exhibition and Hubble, visit:

Hubble Captures 'Shadow Play' Caused by Possible Planet
Sat, 07 Jan 2017 11:15:00 ESTHubble Image

Eerie mysteries in the universe can be betrayed by simple shadows. The wonder of a solar eclipse is produced by the moon's shadow, and over 1,000 planets around other stars have been cataloged by the shadow they cast when passing in front of their parent star. Astronomers were surprised to see a huge shadow sweeping across a disk of dust and gas encircling a nearby, young star. They have a bird's-eye view of the disk, because it is tilted face-on to Earth, and the shadow sweeps around the disk like the hands moving around a clock. But, unlike the hands of a clock, the shadow takes 16 years to make one rotation.

Hubble has 18 years' worth of observations of the star, called TW Hydrae. Therefore, astronomers could assemble a time-lapse movie of the shadow's rotation. Explaining it is another story. Astronomers think that an unseen planet in the disk is doing some heavy lifting by gravitationally pulling on material near the star and warping the inner part of the disk. The twisted, misaligned inner disk is casting its shadow across the surface of the outer disk. TW Hydrae resides 192 light-years away and is roughly 8 million years old.

Hubble Detects 'Exocomets' Taking the Plunge into a Young Star
Fri, 06 Jan 2017 15:15:00 ESTHubble Image

Interstellar forecast for a nearby star: Raining comets! The comets are plunging into the star HD 172555, which resides 95 light-years from Earth. The comets were not seen directly around the star. Astronomers inferred their presence when they used NASA's Hubble Space Telescope to detect gas that is likely the vaporized remnants of their icy nuclei.

The presence of these doomed comets provides circumstantial evidence for "gravitational stirring" by an unseen Jupiter-size planet, where comets deflected by the massive object's gravity are catapulted into the star. These events also provide new insights into the past and present activity of comets in our solar system. It's a mechanism where infalling comets could have transported water to Earth and the other inner planets of our solar system. HD 172555 represents the third extrasolar system where astronomers have detected doomed, wayward comets. All of these systems are young, under 40 million years old.

Hubble Provides Interstellar Road Map for Voyagers' Galactic Trek
Fri, 06 Jan 2017 11:15:00 ESTHubble Image

In 1977, NASA's Voyager 1 and 2 spacecraft began their pioneering journey across the solar system to visit the giant outer planets. Now, the Voyagers are hurtling through unexplored territory on their road trip beyond our solar system. Along the way, they are measuring the interstellar medium, the mysterious environment between stars that is filled with the debris from long-dead stars. NASA's Hubble Space Telescope is providing the road map, by measuring the material along the probes' trajectories as they move through space. Hubble finds a rich, complex interstellar ecology, containing multiple clouds of hydrogen, laced with other elements. Hubble data, combined with the Voyagers, have also provided new insights into how our sun travels through interstellar space.

Festive Nebulas Light Up Milky Way Galaxy Satellite
Tue, 20 Dec 2016 13:00:00 ESTHubble Image

Two glowing nebulas in the Small Magellanic Cloud, a dwarf galaxy that is a satellite of our Milky Way galaxy, have been observed by NASA's Hubble Space Telescope. Young, brilliant stars at the center of each nebula are heating hydrogen, causing these clouds of gas and dust to glow red. The image is part of a study called Small Magellanic Cloud Investigation of Dust and Gas Evolution (SMIDGE). Astronomers are using Hubble to probe the Milky Way satellite to understand how dust is different in galaxies that have a far lower supply of heavy elements needed to create dust.

Space Telescope Science Institute to Host Data from World's Largest Digital Sky Survey
Mon, 19 Dec 2016 08:00:00 ESTHubble Image

Data from the world's largest digital sky survey is being publicly released today by the Space Telescope Science Institute (STScI) in Baltimore, Maryland, in conjunction with the University of Hawaii Institute for Astronomy in Honolulu, Hawaii. Data from the Pan-STARRS1 Surveys will allow anyone to access millions of images and use the database and catalogs containing precision measurements of billions of stars and galaxies. The four years of data comprise 3 billion separate sources, including stars, galaxies, and various other objects. The immense collection contains 2 petabytes of data, which is equivalent to one billion selfies, or one hundred times the total content of Wikipedia.

Full go-ahead for building ExoMars 2020 - Read more >
Fri, 16 Dec 2016 15:00:00 +0100

The first ExoMars mission arrived at the Red Planet in October and now the second mission has been confirmed to complete its construction for a 2020 launch. 

Rosetta’s last words: science descending to a comet - Read more >
Thu, 15 Dec 2016 15:00:00 +0100

ESA’s Rosetta completed its incredible mission on 30 September, collecting unprecedented images and data right until the moment of contact with the comet's surface.

ExoMars orbiter images Phobos - Read more >
Tue, 06 Dec 2016 15:00:00 +0100

The ExoMars Trace Gas Orbiter has imaged the martian moon Phobos as part of a second set of test science measurements made since it arrived at the Red Planet on 19 October.

First views of Mars show potential for ESA’s new orbiter - Read more >
Tue, 29 Nov 2016 11:30:00 +0100

ESA’s new ExoMars orbiter has tested its suite of instruments in orbit for the first time, hinting at a great potential for future observations.

STScI Astronomers Nancy Levenson and David Soderblom Elected AAAS Fellows
Mon, 21 Nov 2016 13:00:00 ESTHubble Image

Nancy A. Levenson and David R. Soderblom of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, have been named Fellows of the American Association for the Advancement of Science (AAAS). Election as an AAAS Fellow is an honor bestowed upon AAAS members by their peers.

The AAAS cited Dr. Levenson for her exemplary service and distinguished contributions to the field of astrophysics as Deputy Director of the international Gemini Observatory in La Serena, Chile. She is currently STScI's Deputy Director. Soderblom is cited by the AAAS for his distinguished work in the field of astrophysics, with contributions to understanding low-mass stars and exoplanet searches. An Astronomer at STScI since 1984, Soderblom is also a Principal Research Scientist at Johns Hopkins University in Baltimore. In honor of their efforts, Levenson, Soderblom, and the 389 other newly elected Fellows will receive an official certificate and a gold and blue (representing science and engineering, respectively) rosette pin on February 18, 2017, at the AAAS Fellows Forum during the 2017 AAAS annual meeting in Boston, Massachusetts. For more information about this announcement, visit

ESA’s new Mars orbiter prepares for first science - Read more >
Fri, 18 Nov 2016 11:00:00 +0100

The ExoMars orbiter is preparing to make its first scientific observations at Mars during two orbits of the planet starting next week.

Icy surprises at Rosetta's comet - Read more >
Thu, 17 Nov 2016 20:00:00 +0100

As Rosetta’s comet approached its most active period last year, the spacecraft spotted carbon dioxide ice – never before seen on a comet – followed by the emergence of two unusually large patches of water ice.

Dr. Laurent Pueyo Receives 2016 Outstanding Young Scientist Award
Wed, 16 Nov 2016 13:00:00 ESTHubble Image

The Maryland Academy of Sciences has selected Dr. Laurent Pueyo of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, as the recipient of the 2016 Outstanding Young Scientist award. He will receive the award in a ceremony on Nov. 16 at the Maryland Science Center, located in Baltimore's Inner Harbor.

Pueyo joined STScI in 2013 as an associate astronomer after spending three years as a Sagan Fellow at Johns Hopkins University in Baltimore. His duties at STScI include working on improving the extrasolar-planet imaging capabilities of NASA's James Webb Space Telescope, scheduled to launch in late 2018. The STScI astronomer was a member of the team, led by STScI's Remi Soummer, that discovered that three planets around the nearby star HR 8799 had been hiding in plain sight since 1998 in archival images taken by Hubble's Near Infrared Camera and Multi-Object Spectrometer.

Schiaparelli crash site in colour - Read more >
Thu, 03 Nov 2016 17:00:00 +0100

New high-resolution images taken by a NASA orbiter show parts of the ExoMars Schiaparelli module and its landing site in colour on the Red Planet.

A record of ancient tectonic stress on Mars - Read more >
Thu, 03 Nov 2016 11:00:00 +0100

Sets of ridges and troughs some 1000 km north of the giant Olympus Mons volcano contain a record of the intense tectonic stresses and strains experienced in the Acheron Fossae region on Mars 3.7–3.9 billion years ago.

A Death Star's Ghostly Glow
Thu, 27 Oct 2016 10:00:00 EDTHubble Image

In writer Edgar Allan Poe's short story "The Tell-Tale Heart," a killer confesses his crime after he thinks he hears the beating of his victim's heart. The heartbeat turns out to be an illusion. Astronomers, however, discovered a real "tell-tale heart" in space, 6,500 light-years from Earth. The "heart" is the crushed core of a long-dead star, called a neutron star, which exploded as a supernova and is now still beating with rhythmic precision. Evidence of its heartbeat are rapid-fire, lighthouse-like pulses of energy from the fast-spinning neutron star. The stellar relic is embedded in the center of the Crab Nebula, the expanding, tattered remains of the doomed star.

The nebula was first identified in 1731 and named in 1844. In 1928, Edwin Hubble linked the nebula to a supernova first witnessed in the spring of 1054 A.D. Now, the eerie glow of the burned-out star reveals itself in this new Hubble Space Telescope snapshot of the heart of the Crab Nebula. The green hue, representative of the broad color range of the camera filter used, gives the nebula a Halloween theme.

STScI Appoints Head of Newly Created Data Science Mission Office
Fri, 21 Oct 2016 11:00:00 EDTHubble Image

Dr. Arfon Smith has been selected to lead the newly created Data Science Mission Office at the Space Telescope Science Institute (STScI) in Baltimore, Maryland. The Data Science Mission Head is responsible for maximizing the scientific returns from a huge archive containing astronomical observations from 17 space astronomy missions and ground-based observatories.

Since 2013, Smith has been a project scientist and program manager at GitHub, Inc., the world's largest platform for open source software. His duties included working to develop innovative strategies for sharing data and software in academia. Smith also helped to define GitHub's business strategy for public data products, and he played a key role in establishing the company's first data science and data engineering teams.

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!
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