Latest Space News
Spot BepiColombo during its ‘goodbye flyby’ - Read more >
Fri, 03 Apr 2020 16:00:00 +0200

BepiColombo Earth flyby

On 10 April, BepiColombo will be visible to amateur and professional astronomers during its first – and only – Earth flyby, as the spacecraft makes its way to Mercury, the innermost planet of the Solar System. The best place to spot it is the southern hemisphere, but observers in southern locations of the northern hemisphere might also catch a parting view of the spacecraft.

Space missions return to science - Read more >
Thu, 02 Apr 2020 09:21:00 +0200

Perspective view of Korolev crater

After a brief shutdown of science instruments and a period in ‘safe standby’, ESA’s planetary missions are getting back to what they do best, gathering science data from around the Solar System.

James Webb Space Telescope's primary mirror unfolded - Read more >
Wed, 01 Apr 2020 17:00:00 +0200

Deployment test of James Webb Space Telescope's primary mirror Image: Deployment test of James Webb Space Telescope's primary mirror

Hubble Finds Best Evidence for Elusive Mid-Sized Black Hole
Tue, 31 Mar 2020 13:00:00 EDT

Hubble Image

Like detectives carefully building a case, astronomers gathered evidence and eliminated suspects until they found the best evidence yet that the death of a star, first witnessed in X-rays, could be traced back to an elusive mid-sized black hole. The result is a long-sought win for astronomy, as the mid-sized "missing link" in the black hole family has thus far thwarted detection. NASA's Hubble Space Telescope was used to follow up on multiple X-ray observations of a suspected tidal disruption event. This is caused when a wayward star comes too close to the gravity well of a black hole and gets shredded by its tidal forces. The intense heat from stellar cannibalism betrays the black hole's presence with a burst of X-rays. Hubble resolved the source region of this X-ray flare as a star cluster outside the Milky Way galaxy. Such clusters have been considered likely places to find an intermediate-mass black hole. The discovery eliminated the possibility that the X-rays came from another type of source within the Milky Way.

ESA to conduct BepiColombo flyby amid coronavirus crisis - Read more >
Mon, 30 Mar 2020 16:00:00 +0200

Controllers at ESA’s mission control centre are preparing for a gravity-assist flyby of the European-Japanese Mercury explorer BepiColombo. The manoeuvre, which will see the mission adjust its trajectory by harnessing Earth’s gravitational pull as it swings past the planet, will be performed amid restrictions ESA has implemented in response to the coronavirus pandemic.

NASA Awards Prize Postdoctoral Fellowships for 2020
Wed, 25 Mar 2020 10:00:00 EDT

Hubble Image

NASA has selected 24 new Fellows for its prestigious NASA Hubble Fellowship Program (NHFP). The program enables outstanding postdoctoral scientists to pursue independent research in any area of NASA Astrophysics, using theory, observation, experimentation, or instrument development. Each fellowship provides the awardee up to three years of support at a university or research center of their choosing in the United States.

ESA scales down science mission operations amid pandemic - Read more >
Tue, 24 Mar 2020 13:00:00 +0100

The inner Solar System

In response to the escalating coronavirus pandemic, ESA has decided to further reduce on-site personnel at its mission control centre in Darmstadt, Germany.

Space science from home: resources for children and adults - Read more >
Fri, 20 Mar 2020 18:00:00 +0100

Space science from home: resources for children and adults

A selection of activities to pass time and learn more about space science

Quasar Tsunamis Rip Across Galaxies
Thu, 19 Mar 2020 13:00:00 EDT

Hubble Image

The weather forecast for galaxies hosting monster, active black holes is blustery. Engorged by infalling material, a supermassive black hole heats so much gas that it can shine 1,000 times brighter than its host galaxy. But that’s not all.

Hubble astronomers found that the region around the black hole emits so much radiation that it pushes out material at a few percent the speed of light (a speed fast enough to travel from Earth to the Moon in a few minutes). This material slams into a host galaxy’s lanes of gas and dust, preventing the formation of new stars. The torrential winds are snowplowing the equivalent of hundreds of solar masses of material each year. And, the forecast is that this stormy weather will continue for at least ten million years.

A massive laboratory - Read more >
Wed, 18 Mar 2020 12:08:00 +0100


This image shows a region of space called LHA 120-N150. It is a substructure of the gigantic Tarantula Nebula. The latter is the largest known stellar nursery in the local Universe. The nebula is situated more than 160 000 light-years away in the Large Magellanic Cloud, a neighbouring dwarf irregular galaxy that orbits the Milky Way.

See the ground-based view here.

Learn more

Ammonium salts found on Rosetta’s comet - Read more >
Fri, 13 Mar 2020 12:00:00 +0100

Ammonium salts found on Rosetta’s comet Image: Ammonium salts found on Rosetta’s comet

ExoMars to take off for the Red Planet in 2022 - Read more >
Thu, 12 Mar 2020 14:57:00 +0100

ExoMars timeline

The European Space Agency (ESA) and the Roscosmos Space Corporation have decided to postpone the launch of the second ExoMars mission to study the Red Planet to 2022.

Slime Mold Simulations Used to Map the Dark Matter Holding the Universe Together
Tue, 10 Mar 2020 13:00:00 EDT

Hubble Image

A simple single-cell organism that may be growing on your lawn is helping astronomers probe the largest structures in the universe.

These organisms, called slime mold, feed on dead plant material, and they have an uncanny ability to seek out food sources. Although brainless, the organism's "genius" at creating efficient networks to reach their food goal has caught the attention of scientists. Researchers have recreated the slime mold's behavior in computer algorithms to help solve large-scale engineering problems such as finding the most efficient traffic routes in large cities, solving mazes, and pinpointing crowd evacuation routes.

A team of astronomers has now turned to slime mold to help them trace the universe's large-scale network of filaments. Built by gravity, these vast cobweb structures, called the cosmic web, tie galaxies and clusters of galaxies together along faint bridges of gas and dark matter hundreds of millions of light-years long.

To trace the filaments, the research team designed a computer algorithm informed by slime-mold behavior. The team seeded the algorithm with the charted positions of 37,000 galaxies and ran it to generate a filamentary map. The astronomers then used archival observations from the Hubble Space Telescope to detect and study the faint gas permeating the web at the predicted locations.

The most powerful black hole eruption in the Universe (with inset) - Read more >
Thu, 27 Feb 2020 17:00:00 +0100

The most powerful black hole eruption in the Universe (with inset) Image: The most powerful black hole eruption in the Universe (with inset)

First instrument delivered for Jupiter Icy Moon Explorer - Read more >
Tue, 25 Feb 2020 16:00:00 +0100

First instrument delivered for Jupiter Icy Moon Explorer Image: First instrument delivered for Jupiter Icy Moon Explorer

Hubble Team Wins the 2020 Michael Collins Trophy
Fri, 21 Feb 2020 13:00:00 EST

Hubble Image

Through its 30 years of discoveries and awesome celestial images, the legendary Hubble Space Telescope has redefined the universe for new generations of astronomers and the public alike. This would not have been possible without the perseverance and expertise of a team of Hubble operations experts at the Space Telescope Science Institute, NASA's Goddard Space Flight Center, and the Lockheed Martin Corporation.

In recognition of Hubble's scientific prowess and longevity, the National Air and Space Museum in Washington, D.C. has awarded their 2020 Collins Trophy for Current Achievement to the Hubble operations team.

"Through the efforts of the Hubble team the observatory has continued to produce research unachievable with any other instrument. System engineers in Hubble's control center and science operations facility have continued to find creative ways to operate the 30-year-old spacecraft to make this revolutionary science possible ensuring its capabilities will continue for years to come," the museum reported.

The Collins Trophy recognizes achievements involving the management or execution of a scientific or technological project, a distinguished career of service in air and space technology, or a significant contribution in chronicling the history of air and space technology.

Beyond the Brim, Sombrero Galaxy's Halo Suggests a Turbulent Past
Thu, 20 Feb 2020 13:00:00 EST

Hubble Image

Like a desperado in the Wild West, the broad "brim" of the Sombrero galaxy's disk may conceal a turbulent past. The Sombrero (M104) has never been a galaxy to fit the mold. It has an intriguing mix of shapes found in disk-shaped spiral galaxies, as well as football-shaped elliptical galaxies. The story of its structure becomes stranger with new evidence from the Hubble Space Telescope indicating the Sombrero is the result of major galaxy mergers, though its smooth disk shows no signs of recent disruption.

The galaxy's faint halo offers forensic clues. It's littered with innumerable stars that are rich in heavier elements (called metals), because they are later-generation stars. Such stars are usually only found in a galaxy's disk. They must have been tossed into the halo through mergers with mature, metal-rich galaxies in the distant past. The iconic galaxy now looks a bit more settled in its later years. It is now so isolated, there is nothing else around to feed on. This finding offers a new twist on how galaxies assemble themselves in our compulsive universe.

Solar Orbiter liftoff - Read more >
Mon, 10 Feb 2020 05:03:00 +0100

Video: 00:00:00

ESA’s new Sun-exploring mission Solar Orbiter lofted to space aboard the US Atlas V 411 rocket from NASA’s spaceport in Cape Canaveral, Florida at 04:03 GMT (05:03 CET) on 10 February 2020.

Solar Orbiter, an ESA-led mission with strong NASA participation, carries a set of ten instruments for imaging the surface of the Sun and studying the environment in its vicinity. The spacecraft will travel around the Sun on an elliptical orbit that will take it as close as 42 million km away from the Sun’s surface, about a quarter of the distance between the Sun and Earth. The orbit will allow Solar Orbiter to see some of the never-before-imaged regions of the Sun, including the poles, and shed new light on what gives rise to solar wind, which can affect infrastructure on Earth.

Solar Orbiter operations simulations - Read more >
Fri, 31 Jan 2020 10:00:00 +0100

Video: 00:03:15

ESA's Solar Orbiter is getting ready for its launch on an Atlas V rocket provided by NASA and operated by United Launch Alliance from Cape Canaveral, Florida.

Once in space, and over the course of several years, the spacecraft will repeatedly use the gravity of Venus and Earth to raise its orbit above the poles of the Sun, providing new perspectives on our star, including the first images of the Sun’s polar regions.

All these operations will be controlled from the European Space Operations Centre (ESOC), Germany, where a dedicated team is currently working on simulations of the first moments in orbit, after separation from the launcher, but also all the delicate manoeuvres of the journey that will make Solar Orbiter mission possible.

The film contains soundbites by Sylvain Lodiot, Spacecraft Operations Manager, Solar Orbiter (English A-roll, French B-roll); and José Manuel Sánchez Pérez, Mission Analyst, Solar Orbiter (English A-roll, English and Spanish B-roll).

Solar Orbiter launch to the Sun - Read more >
Wed, 29 Jan 2020 15:00:00 +0100

Video: 00:02:27

ESA’s Solar Orbiter mission takes a closer look at the Sun than any European satellite before. The sophisticated probe, carrying ten instruments for imaging the surface of our star and measuring the properties of the environment in its vicinity, can be seen in this animation going through parts of the launch and activation sequence. Lofted to space by an Atlas V rocket, Solar Orbiter deploys its 18 m-long solar array (as measured from tip-to-tip), as well as a set of antennas and an instrument boom, as it embarks on its cruise towards the Sun. The spacecraft takes advantage of the gravitational force of Venus and Earth to adjust its trajectory, which will place it into an elliptical orbit around the Sun. Solar Orbiter will get as close as 42 million kilometres to the Sun, about one-quarter of the distance between the Sun and Earth. The orbit will allow Solar Orbiter to see some of the never-before-imaged regions of the Sun, including the poles. Solar Orbiter’s instruments peek at the star through tiny windows in a 30 cm thick titanium foil shield, which protects the spacecraft against the scorching temperatures and constant bombardment by highly charged particles of the solar wind.

Solar Orbiter is an ESA mission with strong NASA participation. Launch is scheduled for February 2020 from Cape Canaveral, Florida, US.

Cheops launch preparations - Read more >
Wed, 29 Jan 2020 14:00:00 +0100

Video: 00:03:14

This timelapse video shows the preparations for the launch of ESA’s Cheops, the Characterising Exoplanet Satellite, at Europe’s Spaceport in Kourou, French Guiana. The video spans about three weeks, starting on 28 November 2019 and ending on 18 December with the liftoff.

Over this period, the fully integrated and fuelled spacecraft was fitted inside the flight adapter of the Soyuz-Fregat rocket, encapsulated within the half-shells of the transport module, transferred to the final integration building, and installed on top of the Fregat upper stage of the Soyuz launcher. The upper composite, enveloped by the rocket fairing and comprises the Fregat and all passengers – the ASI Cosmo-SkyMed Second Generation satellite, Cheops, and three CubeSats: ESA’s OPS-SAT and CNES's EYE-SAT and ANGELS satellites – was eventually transferred to the launch pad area and hoisted on top of the three-stage rocket ahead of liftoff.

Cheops is ESA’s first mission dedicated to the study of extrasolar planets, or exoplanets. It will observe bright stars that are already known to host planets, measuring minuscule brightness changes due to the planet’s transit across the star’s disc.

More about Cheops

NASA's Kepler Witnesses Vampire Star System Undergoing Super-Outburst
Fri, 24 Jan 2020 10:00:00 EST

Hubble Image

Astronomers searching archival data from NASA's Kepler exoplanet hunting mission identified a previously unknown dwarf nova that underwent a super-outburst, brightening by a factor of 1,600 times in less than a day. While the outburst itself has a theoretical explanation, the slow rise in brightness that preceded it remains a mystery. Kepler's rapid cadence of observations were crucial for recording the entire event in detail.

The dwarf nova system consists of a white dwarf star with a brown dwarf companion. The white dwarf is stripping material from the brown dwarf, sucking its essence away like a vampire. The stripped material forms an accretion disk around the white dwarf, which is the source of the super-outburst. Such systems are rare and may go for years or decades between outbursts, making it a challenge to catch one in the act.

Goldilocks Stars Are Best Places to Look for Life
Wed, 08 Jan 2020 15:10:00 EST

Hubble Image

To date astronomers have discovered over 4,000 planets orbiting other stars. Statistically, there should be over 100 billion planets in our Milky Way galaxy. They come in a wide range of sizes and characteristics, largely unimagined before exoplanets were first discovered in the mid-1990s. The biggest motivation for perusing these worlds is to find "Genesis II," a planet where life has arisen and evolved beyond microbes. The ultimate payoff would be finding intelligent life off the Earth.

A major step in searching for habitable planets is finding suitable stars that could foster the emergence of complex organisms. Because our Sun has nurtured life on Earth for nearly 4 billion years, conventional wisdom would suggest that stars like it would be prime candidates. But stars like our Sun represent only about 10% of the Milky Way population. What's more, they are comparatively short-lived. Our Sun is halfway through its estimated 10 billion-year lifetime.

Complex organisms arose on Earth only 500 million years ago. And, the modern form of humans has been here only for the blink of an eye on cosmological timescales: 200,000 years. The future of humanity is unknown. But what is for certain is that Earth will become uninhabitable for higher forms of life in a little over 1 billion years, as the Sun grows warmer and desiccates our planet.

Therefore, stars slightly cooler than our Sun — called orange dwarfs — are considered better hang-outs for advanced life. They can burn steadily for tens of billions of years. This opens up a vast timescape for biological evolution to pursue an infinity of experiments for yielding robust life forms. And, for every star like our Sun there are three times as many orange dwarfs in the Milky Way.

The only type of star that is more abundant are red dwarfs. But these are feisty little stars. They are so magnetically active they pump out 500 times as much radiation in the form of X-rays and ultraviolet light as our Sun does. Planets around these stars take a beating. They would be no place to call home for organisms like us.

An emerging idea, bolstered by stellar surveys performed by Hubble and other telescopes, is that the orange dwarfs are "Goldilocks stars" — not too hot, not too cool, and above all, not too violent to host life-friendly planets over a vast horizon of cosmic time.

Cosmic Magnifying Glasses Yield Independent Measure of Universe's Expansion
Wed, 08 Jan 2020 14:55:00 EST

Hubble Image

People use the phrase "Holy Cow" to express excitement. Playing with that phrase, researchers from an international collaboration developed an acronym—H0LiCOW—for their project's name that expresses the excitement over their Hubble Space Telescope measurements of the universe's expansion rate.

Knowing the precise value for how fast the universe expands is important for determining the age, size, and fate of the cosmos. Unraveling this mystery has been one of the greatest challenges in astrophysics in recent years.

Members of the H0LiCOW (H0 Lenses in COSMOGRAIL's Wellspring) team used Hubble and a technique that is completely independent of any previous method to measure the universe's expansion, a value called the Hubble constant.

This latest value represents the most precise measurement yet using the gravitational lensing method, where the gravity of a foreground galaxy acts like a giant magnifying lens, amplifying and distorting light from background objects. This latest study did not rely on the traditional "cosmic distance ladder" technique to measure accurate distances to galaxies by using various types of stars as "milepost markers." Instead, the researchers employed the exotic physics of gravitational lensing to calculate the universe's expansion rate.

The researchers' result further strengthens a troubling discrepancy between the expansion rate calculated from measurements of the local universe and the rate as predicted from background radiation in the early universe, a time before galaxies and stars even existed. The new study adds evidence to the idea that new theories may be needed to explain what scientists are finding.

Hubble Detects Smallest Known Dark Matter Clumps
Wed, 08 Jan 2020 14:40:00 EST

Hubble Image

When searching for dark matter, astronomers must go on a sort of "ghost hunt." That's because dark matter is an invisible substance that cannot be seen directly. Yet it makes up the bulk of the universe's mass and forms the scaffolding upon which galaxies are built. Dark matter is the gravitational "glue" that holds galaxies as well as galaxy clusters together. Astronomers can detect its presence indirectly by measuring how its gravity affects stars and galaxies.

The mysterious substance is not composed of the same stuff that makes up stars, planets, and people. That material is normal "baryonic" matter, consisting of electrons, protons, and neutrons. However, dark matter might be some sort of unknown subatomic particle that interacts weakly with normal matter.

A popular theory holds that dark matter particles don't move very fast, which makes it easier for them to clump together. According to this idea, the universe contains a broad range of dark matter concentrations, from small to large.

Astronomers have detected dark matter clumps around large- and medium-sized galaxies. Now, using Hubble and a new observing technique, astronomers have found that dark matter forms much smaller clumps than previously known.

The researchers searched for small concentrations of dark matter in the Hubble data by measuring how the light from faraway quasars is affected as it travels through space. Quasars are the bright black-hole-powered cores of very distant galaxies. The Hubble images show that the light from these quasars images is warped and magnified by the gravity of massive foreground galaxies in an effect called gravitational lensing. Astronomers used this lensing effect to detect the small dark matter clumps. The clumps are located along the telescope’s line of sight to the quasars, as well as in and around the foreground lensing galaxies.

NASA's Hubble Surveys Gigantic Galaxy
Sun, 05 Jan 2020 15:15:00 EST

Hubble Image

Galaxies are like snowflakes. Though the universe contains innumerable galaxies flung across time and space, no two ever look alike. One of the most photogenic is the huge spiral galaxy UGC 2885, located 232 million light-years away in the northern constellation, Perseus. It's a whopper even by galactic standards. The galaxy is 2.5 times wider than our Milky Way and contains 10 times as many stars, about 1 trillion. This galaxy has lived a quiescent life by not colliding with other large galaxies. It has gradually bulked up on intergalactic hydrogen to make new stars at a slow and steady pace over many billions of years. The galaxy has been nicknamed "Rubin's galaxy," after astronomer Vera Rubin (1928 – 2016). Rubin used the galaxy to look for invisible dark matter. The galaxy is embedded inside a vast halo of dark matter. The amount of dark matter can be estimated by measuring its gravitational influence on the galaxy's rotation rate.

NASA's Great Observatories Help Astronomers Build a 3D Visualization of Exploded Star
Sun, 05 Jan 2020 14:30:00 EST

Hubble Image

In the year 1054 AD, Chinese sky watchers witnessed the sudden appearance of a "new star" in the heavens, which they recorded as six times brighter than Venus, making it the brightest observed stellar event in recorded history. This "guest star," as they described it, was so bright that people saw it in the sky during the day for almost a month. Native Americans also recorded its mysterious appearance in petroglyphs.

Observing the nebula with the largest telescope of the time, Lord Rosse in 1844 named the object the "Crab" because of its tentacle-like structure. But it wasn't until the 1900s that astronomers realized the nebula was the surviving relic of the 1054 supernova, the explosion of a massive star.

Now, astronomers and visualization specialists from the NASA's Universe of Learning program have combined the visible, infrared, and X-ray vision of NASA's Great Observatories to create a three-dimensional representation of the dynamic Crab Nebula.

The multiwavelength computer graphics visualization is based on images from the Chandra X-ray Observatory and the Hubble and Spitzer space telescopes. The approximately four-minute video dissects the intricate nested structure that makes up this stellar corpse, giving viewers a better understanding of the extreme and complex physical processes powering the nebula. The powerhouse "engine" energizing the entire system is a pulsar, a rapidly spinning neutron star, the super-dense crushed core of the exploded star. The tiny dynamo is blasting out blistering pulses of radiation 30 times a second with unbelievable clockwork precision.

Simulated Image Demonstrates the Power of NASA's Wide Field Infrared Survey Telescope
Sun, 05 Jan 2020 14:00:00 EST

Hubble Image

NASA's upcoming Wide Field Infrared Survey Telescope (WFIRST), scheduled for launch in the mid-2020s, will have the power to survey the sky 1,000 times faster than the Hubble Space Telescope, with Hubble-quality detail, in the near-infrared.

A simulated image of a 34,000-light-year swath across our neighboring galaxy Andromeda showcases WFIRST’s unique detector configuration, expansive field of view and high resolution. The image was generated using data collected by Hubble, and shows the red and infrared light of more than 50 million individual stars in Andromeda, as they would appear with WFIRST.

WFIRST is designed to address key questions across a wide range of topics, including dark energy, exoplanets, and general astrophysics spanning from our solar system to the most distant galaxies in the observable universe. WFIRST is expected to amass more than 4 petabytes of information per year, all of which will be non-proprietary and immediately accessible to the public.

The simulated image, which represents the staggering amount of data that could be captured in a single pointing over just 90 minutes, demonstrates the power of WFIRST for examining large-scale structures that are otherwise too time-consuming to image. Astronomers are currently using simulations like this to plan future observations.

'Cotton Candy' Planet Mysteries Unravel in New Hubble Observations
Thu, 19 Dec 2019 13:00:00 EST

Hubble Image

When astronomers look around the solar system, they find that planets can be made out of almost anything. Terrestrial planets like Earth, Mars, and Venus have dense iron cores and rocky mantles. The massive outer planets like Jupiter and Saturn are mostly gaseous and liquid. Astronomers can't peel back their cloud layers to look inside, but their composition is deduced by comparing the planet's mass (as calculated from its orbital motion) to its size. The result is that Jupiter has the density of water, and Saturn has an even lower density (it could float in a huge bathtub). These gas giants are just 1/5th the density of rocky Earth.

Now astronomers have uncovered a completely new class of planet unlike anything found in our solar system. Rather than a "terrestrial" or "gas giant" they might better be called "cotton candy" planets because their density is so low. These planets are so bloated they are nearly the size of Jupiter, but are just 1/100th of its mass. Three of them orbit the Sun-like star Kepler 51, located approximately 2,600 light-years away.

The puffed-up planets might represent a brief transitory phase in planet evolution, which would explain why we don't see anything like them in the solar system. The planets may have formed much farther from their star and migrated inward. Now their low-density hydrogen/helium atmospheres are bleeding off into space. Eventually, much smaller planets might be left behind.

STScI Astronomers Kathryn Flanagan and Colin Norman Elected AAAS Fellows
Mon, 16 Dec 2019 10:00:00 EST

Hubble Image

The American Association for the Advancement of Science (AAAS) Council has elected Kathryn Flanagan of the Space Telescope Science Institute (STScI) and Colin Norman of STScI and Johns Hopkins University, and 441 other AAAS members as Fellows of the AAAS.

Dr. Flanagan is cited by the AAAS for her lead role calibrating grating spectrometers for NASA's Chandra X-ray Observatory mission; X-ray observations of astrophysical plasmas; and leadership in the James Webb Space Telescope project.

Dr. Norman is cited by the AAAS for distinguished contributions to an array of subjects in theoretical astrophysics, especially in the areas of the interstellar medium, galaxy dynamics, star formation, and galaxy clusters.

For more information about this announcement, visit the AAAS website.

Interstellar Comet 2I/Borisov Swings Past the Sun
Thu, 12 Dec 2019 13:00:00 EST

Hubble Image

When astronomers see something in the universe that at first glance seems like one-of-a-kind, it's bound to stir up a lot of excitement and attention. Enter comet 2I/Borisov. This mysterious visitor from the depths of space is the first identified comet to arrive here from another star. We don't know from where or when the comet started heading toward our Sun, but it won't hang around for long. The Sun's gravity is slightly deflecting its trajectory, but can't capture it because of the shape of its orbit and high velocity of about 100,000 miles per hour.

Telescopes around the world have been watching the fleeting visitor. Hubble has provided the sharpest views as the comet skirts by our Sun. Since October the space telescope has been following the comet like a sports photographer following horses speeding around a racetrack. Hubble revealed that the heart of the comet, a loose agglomeration of ices and dust particles, is likely no more than about 3,200 feet across, about the length of nine football fields. Though comet Borisov is the first of its kind, no doubt there are many other comet vagabonds out there, plying the space between stars. Astronomers will eagerly be on the lookout for the next mysterious visitor from far beyond.

Hubble Studies Gamma-Ray Burst with the Highest Energy Ever Seen
Wed, 20 Nov 2019 13:00:00 EST

Hubble Image

The Star Wars film trilogies are known best for the iconic "Death Star," an alien battle station that shoots out beams of directed energy powerful enough to blow up planets. The real universe makes much more extraordinary beams that can unleash in a few seconds as much energy as our sun will generate over its 10-billion-year lifetime. These beams blast out of imploding stars at over 99% the speed of light. They carry most of their energy in the form of gamma-rays—a lethal form of radiation that can penetrate bone and tear apart living cells. If our planet got caught in a nearby gamma-ray burst (GRB) the atmosphere would be largely stripped away.

The current record for a super-powerful GRB goes to a January 2019 outburst. The eruption came from a galaxy located so far away that the explosion actually happened 5 billion years ago. When the diluted radiation finally arrived at Earth, it was seen by our satellite sentries that monitor the sky for such fireworks: NASA’s Swift and Fermi telescopes, in addition to the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes on the Canary islands.

Hubble can't detect gamma-rays, but its sharp vision was used to see where the burst came from. The host galaxy of the GRB is actually one of a pair of colliding galaxies. The galaxy interactions may have contributed to the blast.

A Weakened Black Hole Allows Its Galaxy To Awaken
Mon, 18 Nov 2019 13:00:00 EST

Hubble Image

Supermassive black holes, weighing millions or even billions of times our Sun's mass, are still only a tiny fraction of the mass of the galaxies they inhabit. But in some cases, the central black hole is the tail wagging the dog. It seems that black holes can run hot or cold when it comes to either enhancing or squelching star birth inside a cluster of galaxies.

Typically, giant black holes, pumping out energy via jets, keep interstellar gas too warm to condense and form stars. Now, astronomers have found a cluster of galaxies, called the Phoenix cluster, where stars are forming at a furious rate because of the black hole's influence. This stellar turboboost is apparently linked to less energetic jets from a central black hole that do not pump up the gas temperature. Instead, the gas loses energy as it glows in X-rays. The gas cools to where it can form large numbers of stars at a breathtaking rate. Where our Milky Way forms one star per year on average, newborn stars are popping out of this cool gas at a rate of about 500 solar masses per year in the Phoenix cluster.

Unraveling this mystery required the combined power of NASA's Hubble Space Telescope, NASA's Chandra X-ray Observatory, and the Very Large Array (VLA) radio observatory near Socorro, New Mexico.

The VLA radio data reveals jets blasting out from the vicinity of the central black hole. These jets inflated bubbles in the hot gas that are detected in X-rays by Chandra. Hubble resolves bright blue filaments of newborn stars in cavities between the hot jet and gas clouds. As the black hole has grown more massive and more powerful, its influence has been increasing.