Category Archives: Hubble

Hubble Sees NGC 4051

Not quite what I was going to post, but I need the practice. It’s a good thing though. I’ll explain; but first about the image:

ESA: When massive stars die at the end of their short lives, they light up the cosmos with bright, explosive bursts of light and material known as supernovae. A supernova event is incredibly energetic and intensely luminous — so much so that it forms what looks like an especially bright new star that slowly fades away over time.

These exploding stars glow so incredibly brightly when they first form that they can be spotted from afar using telescopes such as the NASA/ESA Hubble Space Telescope. The subject of this image, a spiral galaxy named NGC 4051 — about 45 million light-years from Earth — has hosted multiple supernovae in past years. The first was spotted in 1983 (SN 1983I), the second in 2003 (SN 2003ie), and the most recent in 2010 (SN 2010br). These explosive events were seen scattered throughout the centre and spiral arms of NGC 4051.

The SN 1983I and SN 2010br were both categorised as supernovae of type Ic. This type of supernova is produced by the core collapse of a massive star that has lost its outer layer of hydrogen and helium, either via winds or by mass transfer to a companion. Because of this, type Ic — and also type Ib — supernovae are sometimes referred to as stripped core-collapse supernovae.

This galaxy’s beautiful spiral structure can be seen well in this image, along with other intriguing objects (including an emission-line galaxy known as SDSS J120312.35+443045.1, visible as the bright smudge to the lower middle of the image, beneath the sweeping arm of NGC 4051).NGC 4501 sits in the southern part of a cluster of galaxies known as the Ursa Major I Cluster; this cluster is especially rich in spirals such as NGC 4051, and is a subset of the larger Virgo Supercluster, which also houses the Milky Way.

Image: ESA/Hubble & NASA, D. Crenshaw and O. Fox; CC BY 4.0

Practice? I finally was forced to retire my old laptop. Keyboard was coming off, there was a crack along the back of the screen and another along the bottom. Other than not being worth anything for image processing ability, it was a decent machine. So here I am with a new computer, that can work with graphics (I have a Juno image all queued up to have a go with). The thing is this computer has a different operating system than what i am used to. Things work, just differently.

Hubble’s Look at NGC 7773

Very nice look at NGC 7773 from Hubble.

NASA: This striking image was taken by the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 (WFC3), a powerful instrument installed on the telescope in 2009. WFC3 is responsible for many of Hubble’s most breathtaking and iconic photographs.

Shown here, NGC 7773 is a beautiful example of a barred spiral galaxy. A luminous bar-shaped structure cuts prominently through the galaxy’s bright core, extending to the inner boundary of NGC 7773’s sweeping, pinwheel-like spiral arms. Astronomers think that these bar structures emerge later in the lifetime of a galaxy, as star-forming material makes its way towards the galactic center — younger spirals do not feature barred structures as often as older spirals do, suggesting that bars are a sign of galactic maturity. They are also thought to act as stellar nurseries, as they gleam brightly with copious numbers of youthful stars.

Our galaxy, the Milky Way, is thought to be a barred spiral like NGC 7773. By studying galactic specimens such as NGC 7773 throughout the universe, researchers hope to learn more about the processes that have shaped — and continue to shape — our cosmic home.

Text credit: ESA (European Space Agency)
Image credit: ESA/Hubble & NASA, J. Walsh

Galactic Hit-and-Run


Hubble et al.: The irregular galaxy NGC 4485 shows all the signs of having been involved in a hit-and-run accident with a bypassing galaxy. Rather than destroying the galaxy, the chance encounter is spawning a new generation of stars, and presumably planets.

The right side of the galaxy is ablaze with star formation, shown in the plethora of young blue stars and star-incubating pinkish nebulas. The left side, however, looks intact. It contains hints of the galaxy’s previous spiral structure, which, at one time, was undergoing normal galactic evolution.

The larger culprit galaxy, NGC 4490, is off the bottom of the frame. The two galaxies sideswiped each other millions of years ago and are now 24,000 light-years apart. The gravitational tug-of-war between them created rippling patches of higher-density gas and dust within both galaxies. This activity triggered a flurry of star formation.

This galaxy is a nearby example of the kind of cosmic bumper-car activity that was more common billions of years ago when the universe was smaller and galaxies were closer together.

NGC 4485 lies 25 million light-years away in the northern constellation Canes Venatici (the Hunting Dogs).

This new image, captured by Hubble’s Wide Field Camera 3 (WFC3), provides further insight into the complexities of galaxy evolution.

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

Text credit: Space Telescope Science Institute
Image credit: NASA, ESA; acknowledgment: T. Roberts (Durham University, UK), D. Calzetti (University of Massachusetts) and the LEGUS Team, R. Tully (University of Hawaii) and R. Chandar (University of Toledo)

Forgotten Pictor?

One of those areas of the sky I can’t see here from the north. Hubble really helps bring it to life too. Edit; Oops forgot the title of all things.

Constellation Pictor finders chart and information.

ESA/Hubble: Dotted across the sky in the constellation of Pictor (The Painter’s Easel) is the galaxy cluster highlighted here by the NASA/ESA Hubble Space Telescope: SPT-CL J0615-5746, or SPT0615 for short. First discovered by the South Pole Telescope less than a decade ago, SPT0615 is exceptional among the myriad clusters so far catalogued in our map of the Universe — it is the highest-redshift cluster for which a full, strong lens model is published.

SPT0615 is a massive cluster of galaxies, one of the farthest observed to cause gravitational lensing. Gravitational lensing occurs when light from a background object is deflected around mass between the object and the observer. Among the identified background objects, there is SPT0615-JD, a galaxy that is thought to have emerged just 500 million years after the Big Bang. This puts it among the very earliest structures to form in the Universe. It is also the farthest galaxy ever imaged by means of gravitational lensing.

Just as ancient paintings can tell us about the period of history in which they were painted, so too can ancient galaxies tell us about the era of the Universe in which they existed. To learn about cosmological history, astronomers explore the most distant reaches of the Universe, probing ever further out into the cosmos. The light from distant objects travels to us from so far away that it takes an immensely long time to reach us, meaning that it carries information from the past — information about the time at which it was emitted.

By studying such distant objects, astronomers are continuing to fill the gaps in our picture of what the very early Universe looked like, and uncover more about how it evolved into its current state.

Image: ESA/Hubble & NASA, I. Karachentsev et al., F. High et al.CC BY 4.0

Hubble Looks at NGC 2903

NGC 2903 was discovered by William Hershel in 1784. Although this spiral galaxy was certainly bright enough to be seen by Charles Messier he never added it to his famous catalog. There is an entry for it in the SEDS site.

As for this lovely image from Hubble ESA writes:

Few of the Universe’s residents are as iconic as the spiral galaxy. These limelight-hogging celestial objects combine whirling, pinwheeling arms with scatterings of sparkling stars, glowing bursts of gas, and dark, weaving lanes of cosmic dust, creating truly awesome scenes — especially when viewed through a telescope such as the NASA/ESA Hubble Space Telescope. In fact, this image from Hubble frames a perfect spiral specimen: the stunning NGC 2903.

NGC 2903 is located about 30 million light-years away in the constellation of Leo (The Lion), and was studied as part of a Hubble survey of the central regions of roughly 145 nearby disc galaxies. This study aimed to help astronomers better understand the relationship between the black holes that lurk at the cores of galaxies like these, and the rugby-ball-shaped bulge of stars, gas, and dust at the galaxy’s centre — such as that seen in this image.

Image: ESA/Hubble & NASA, L. Ho et al.; CC BY 4.0

The Egg

ESA: The Egg Nebula is a preplanetary nebula, created by a dying star in the process of becoming a planetary nebula. Planetary nebulas have nothing to do with planets – the name arose when 18th century astronomers spotted them in their telescopes and thought they looked like planets. Instead, they are the remnants of material expelled by Sun-like stars in the later stages of their lives.

The preplanetary nebula phase is extremely short-lived in astronomical terms – only a few thousand years. This makes them rare objects and, combined with the fact that they are quite faint, rather difficult to spot. The Egg Nebula, located around 3000 light years from us, was the first of its kind to be discovered in the 1970s. This image is based on observations performed in the mid 1990s by the Wide Field and Planetary Camera 2 (WFPC2) on the NASA/ESA Hubble Space Telescope.

During the preplanetary nebula phase, the central star periodically sheds its outer layers, which are then illuminated by the dying star at the centre. Eventually the star stops shedding material and the core remnant heats up, exciting the expelled gas so that it glows brightly and becomes a planetary nebula.

The dark band, sweeping beams, and criss-crossing arcs in this image can reveal a lot about the complex environment of a dying star. The central band is a cocoon of dust hiding the star from view.

Beams of light emanate from the obscured star, and it is thought that they are due to starlight escaping from the ring-shaped holes in the dusty cocoon that surrounds the star. The holes are possibly carved by a high-speed stream of matter, although the cause of these jets are unknown. The spoke-like features are shadows cast by blobs of material within the region of the holes in the cocoon.

Numerous bright arcs intersect the beams: these are shells of matter ejected by the star. The arcs are like tree rings, and can tell us something about the object’s age as they reveal that the rate of mass ejection has varied between 100 and 500 years throughout its 10 000 year history. The gas is expanding at a rate of 20 km/s and matter has been detected out to a radius of 0.6 light years, providing an estimate of the amount of matter in the nebula.

Image: R. Sahai and J. Trauger (JPL), the WFPC2 science team, and NASA/ESA

The Southern Crab

Wow! Amazing image of an amazing event.

You can get a larger version by clicking the image above. ESA provided a link for a much larger image that I highly recommend you look at, it’s a little large (1.13 MB) and well worth the download.

Image: NASA, ESA, and STScI

ESA: This incredible image of the hourglass-shaped Southern Crab Nebula was taken to mark the NASA/ESA Hubble Space Telescope’s 29th anniversary in space. The nebula, created by a binary star system, is one of the many objects that Hubble has demystified throughout its productive life. This new image adds to our understanding of the nebula and demonstrates the telescope’s continued capabilities.

On 24 April 1990, the NASA/ESA Hubble Space Telescope was launched on the space shuttle Discovery. It has since revolutionised how astronomers and the general public see the Universe. The images it provides are spectacular from both a scientific and a purely aesthetic point of view.

Each year the telescope dedicates a small portion of its precious observing time to take a special anniversary image, focused on capturing particularly beautiful and meaningful objects. This year’s image is the Southern Crab Nebula, and it is no exception [1].

This peculiar nebula, which exhibits nested hourglass-shaped structures, has been created by the interaction between a pair of stars at its centre. The unequal pair consists of a red giant and a white dwarf. The red giant is shedding its outer layers in the last phase of its life before it too lives out its final years as a white dwarf. Some of the red giant’s ejected material is attracted by the gravity of its companion.

When enough of this cast-off material is pulled onto the white dwarf, it too ejects the material outwards in an eruption, creating the structures we see in the nebula. Eventually, the red giant will finish throwing off its outer layers, and stop feeding its white dwarf companion. Prior to this, there may also be more eruptions, creating even more intricate structures.

Astronomers did not always know this, however. The object was first written about in 1967, but was assumed to be an ordinary star until 1989, when it was observed using telescopes at the European Southern Observatory‘s La Silla Observatory. The resulting image showed a roughly crab-shaped extended nebula, formed by symmetrical bubbles of gas and dust.

These observations only showed the outer hourglass emanating from a bright central region that could not be resolved. It was not until Hubble observed the Southern Crab in 1999 that the entire structure came into view. This image revealed the inner nested structures, suggesting that the phenomenon that created the outer bubbles had occurred twice in the (astronomically) recent past.

It is fitting that Hubble has returned to this object twenty years after its first observation. This new image adds to the story of an active and evolving object and contributes to the story of Hubble’s role in our evolving understanding of the Universe.


[1] The Southern Crab Nebula is so named to distinguish it from the better-known Crab Nebula, a supernova remnant visible in the constellation of Taurus.

Hubble’s Look at M2

Hubble’s look at the globular cluster first cataloged by Charles Messier in 1760.

Be SURE to visit the Charles Messier’s Catalog of Nebulae and Star Clusters at SEDS. Excellent site!

Hubble et. al: Star clusters are commonly featured in cosmic photoshoots, and are also well-loved by the keen eye of the NASA/ESA Hubble Space Telescope. These large gatherings of celestial gems are striking sights — and Messier 2 is certainly no exception.

Messier 2 is located in the constellation of Aquarius (the Water Bearer), about 55,000 light-years away. It is a globular cluster, a spherical group of stars all tightly bound together by gravity. With a diameter of roughly 175 light-years, a population of 150,000 stars, and an age of 13 billion years, Messier 2 is one of the largest clusters of its kind and one of the oldest associated with the Milky Way.

This Hubble image of Messier 2’s core was created using visible and infrared light. Most of the cluster’s mass is concentrated at its center, with shimmering streams of stars extending outward into space. It is bright enough that it can even be seen with the naked eye when observing conditions are extremely good.

Messier 2 is featured in Hubble’s Messier catalog, which includes some of the most fascinating objects that can be observed from Earth’s Northern Hemisphere. See the NASA-processed image and other Messier objects at:

Text credit: ESA (European Space Agency)
Image credit: ESA/Hubble & NASA, G. Piotto et al.

Wild Duck Cluster

The Wild Duck Cluster also known as Messier 11 in the famous catalog by Charles Messier. It’s in a fun area of the sky for viewing, Of course we won’t see it like this look from Hubble, but it’s an excellent area to peruse.

Hubble (et. al.): This star-studded image shows us a portion of Messier 11, an open star cluster in the southern constellation of Scutum (the Shield). Messier 11 is also known as the Wild Duck Cluster, as its brightest stars form a “V” shape that somewhat resembles a flock of ducks in flight.

Messier 11 is one of the richest and most compact open clusters currently known. By investigating the brightest, hottest main sequence stars in the cluster, astronomers estimate that it formed roughly 220 million years ago. Open clusters tend to contain fewer and younger stars than their more compact globular cousins, and Messier 11 is no exception: at its center lie many blue stars, the hottest and youngest of the cluster’s few thousand stellar residents.

The lifespans of open clusters are also relatively short compared to those of globular ones; stars in open clusters are spread farther apart and are thus not as strongly bound to each other by gravity, causing them to be more easily and quickly drawn away by stronger gravitational forces. As a result, Messier 11 is likely to disperse in a few million years as its members are ejected one by one, pulled away by other celestial objects in the vicinity.

Messier 11 is featured in Hubble’s Messier catalog, which includes some of the most fascinating objects that can be observed from Earth’s Northern Hemisphere. See the NASA-processed image and other Messier objects at:

Text credit: ESA (European Space Agency)
Image credit: ESA/Hubble & NASA, P. Dobbie et al.

Merging Galaxies

Can you image being on a planet in either one of these colliding galaxies? One day in the very far future this might be a good analogy of our merging with the Andromeda galaxy. What would the sky look like, even in the daytime?

ESA: Located in the constellation of Hercules, about 230 million light-years away, NGC 6052 is a pair of colliding galaxies. They were first discovered in 1784 by William Herschel and were originally classified as a single irregular galaxy because of their odd shape. However, we now know that NGC 6052 actually consists of two galaxies that are in the process of colliding. This particular image of NGC 6052 was taken using the Wide Field Camera 3 on the NASA/ESA Hubble Space Telescope.

A long time ago gravity drew the two galaxies together into the chaotic state we now observe. Stars from within both of the original galaxies now follow new trajectories caused by the new gravitational effects. However, actual collisions between stars themselves are very rare as stars are very small relative to the distances between them (most of a galaxy is empty space). Eventually things will settle down and one day the two galaxies will have fully merged to form a single, stable galaxy.

Our own galaxy, the Milky Way, will undergo a similar collision in the future with our nearest galactic neighbour, the Andromeda Galaxy. Although this is not expected to happen for around 4 billion years so there is nothing to worry about just yet.

This object was previously observed by Hubble with its old WFPC2 camera. That image was released in 2015.

Image: ESA/Hubble & NASA, A. Adamo et al.; CC BY 4.0