Tag: Hubble

Baby stars illuminating the dust that surrounds them

10:03 am

Baby stars illuminating dark dust
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope showing the wispy bluish clouds made of dark dust that we can only see because the dust is illuminated by the reflected light from the five red and blue stars nearby. Think of the Moon, lit only by the reflected light of the Sun.

The photo however was not taken to study the clouds, but these baby stars, located in one of the closest star forming regions of the Milky Way.

GN 04.32.8 is a small part of the stellar nursery known as the Taurus Molecular Cloud. At only roughly 480 light-years from Earth in the constellation Taurus, it’s one of the best locations for studying newly forming stars. This reflection nebula is illuminated by the system of three bright stars in the centre of this image, mainly the variable star V1025 Tauri in the very centre. One of those stars overlaps with part of the nebula: this is another variable star that is named HP Tauri, but is classified as a T Tauri star, for its similarity to yet another variable star elsewhere in the Taurus Molecular Complex. T Tauri stars are very active, chaotic stars at an early stage of their evolution, so it’s no surprise that they appear in a prolific stellar nursery like this one! The three stars are also named HP Tau, HP Tau G2 and HP Tau G3; they’re believed to be gravitationally bound to each other, forming a triple system.

Eagle-eyed viewers might notice the small, squashed, orange spot, just left of centre below the clouds of the nebula, that’s crossed by a dark line. This is a newly-formed protostar, hidden in a protoplanetary disc that obstructs some of its light. Because the disc is edge-on to us, it’s an ideal candidate for study. Astronomers are using Hubble here to examine it closely, seeking to learn about the kinds of exoplanets that might be formed in discs like it.

As beautiful as this image is, it is that tiny protostar near the bottom that likely attracts the most interest from astronomers.

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A graceful spiral galaxy

2:35 pm

A graceful spiral galaxy
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a project to study galaxies with very active central supermassive black holes.

What sets UGC 11397 apart from a typical spiral lies at its centre, where a supermassive black hole containing 174 million times the mass of the Sun is growing. As a black hole ensnares gas, dust, and even entire stars from its vicinity, this doomed matter heats up and puts on a fantastic cosmic light show. Material trapped by the black hole emits light from gamma rays to radio waves and can brighten and fade without warning. But in some galaxies, including UGC 11397, thick clouds of dust hide much of this energetic activity from view in optical light. Despite this, UGC 11397’s actively growing black hole was revealed through its bright X-ray emission — high-energy light that can pierce the surrounding dust. This led astronomers to classify it as a Type 2 Seyfert galaxy, a category used for active galaxies whose central regions are hidden from view in visible light by a doughnut-shaped cloud of dust and gas.

To me what sets this galaxy apart is its natural beauty. It also reminds me of the universe’s vastness. Located about 250 million light years away, those hazy spiral arms represent millions of stars, many of which likely harbor planets and maybe even life.

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New calculations suggest Andromeda might not collide with Milky Way

9:00 am

The uncertainty of science: Scientists using new data from the Hubble Space Telescope as well as Europe’s Gaia space telescope, combined with many computer models, have determined that the 2012 prediction that the Andromeda galaxy would collide with Milky Way in five billion years was much more uncertain. From the abstract of the paper:

[W]e consider the latest and most accurate observations by the Gaia and Hubble space telescopes, along with recent consensus mass estimates, to derive possible future scenarios and identify the main sources of uncertainty in the evolution of the Local Group over the next 10 billion years. We found that the next most massive Local Group member galaxies — namely, M33 and the Large Magellanic Cloud—distinctly and radically affect the Milky Way — Andromeda orbit. Although including M33 increases the merger probability, the orbit of the Large Magellanic Cloud runs perpendicular to the Milky Way–Andromeda orbit and makes their merger less probable.

In the full system, we found that uncertainties in the present positions, motions and masses of all galaxies leave room for drastically different outcomes and a probability of close to 50% that there will be no Milky Way–Andromeda merger during the next 10 billion years. Based on the best available data, the fate of our Galaxy is still completely open.

The press release at the first link above makes it sounds as the previous prediction of a collision had been fully accepted as certain by the entire astronomical community, and that is balder-dash. It was simply the best guess at the time, highly uncertain. This new prediction — that we really don’t know what will happen based on the data available — is simply the newest best guess.

This new analysis however is certainly more robust and honest.

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NASA unwittingly reveals its bankruptcy by its reliance on AI

10:11 am

Uranus as seen by Hubble in 2014 and 2022
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In what appeared to be a totally inexplicable press release today, NASA posted the two pictures of Uranus to the right. The accompanying text was truly puzzling, describing in a somewhat brainless and inaccurate manner what is in the pictures;

Two views of the planet Uranus appear side-by-side for comparison. At the top, left corner of the left image is a two-line label. The top line reads Uranus November 9, 2014. The bottoms line reads HST WFC3/UVIS. At the top, left corner of the right image is the label November 9, 2022. At the left, bottom corner of each image is a small, horizontal, white line. In both panels, over this line is the value 25,400 miles. Below the line is the value 40,800 kilometers. At the top, right corner of the right image are three, colored labels representing the color filters used to make these pictures. Located on three separate lines, these are F467M in blue, F547M in green, and F485M in red. On the bottom, right corner of the right image are compass arrows showing north toward the top and east toward the left. [emphasis mine]

First, the description doesn’t match the pictures precisely, as if whoever wrote it wasn’t looking at these pictures. Second, the description is ridiculously literal, and really provides no information at all. (Consider for example the highlighted sentence. All it is doing is describing a standard scale bar, in the strangest most stupid manner possible.)

I immediately surmised that someone at NASA has decided to use AI to do this work, and AI (in its typical stupid brilliance) provided this worthless text. The unnamed NASA employee — equally as stupid — then posted it without reading it, assuming AI had done his or her job perfectly.

What makes this display of stupidity even worse is that these pictures, and a real press release, were issued back in 2023, when I posted these pictures initially. Does no one at NASA ever bother to read their own press releases?

Apparently not. The advent of AI has now produced human employees at the space agency who read nothing, know nothing, and do nothing. They instead plug stuff into AI and pump it out to the public mindlessly.

No wonder Trump wants to slash NASA’s budget. We certainly ain’t getting our money’s worth from the people that are there.

I also fully expect NASA management to soon deep-six this press release, or to fix it quickly once they read this post.

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A galactic pinwheel

8:39 am

A galactic pinwheel
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It’s cool image time, partly because we have a cool image and partly because there is little news today due to the holiday. The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope and was released today as the science team’s picture of the week. It shows us a classic pinwheel galaxy located approximately 46 million light years away. From the caption:

A spiral galaxy seen face-on. Its centre is crossed by a broad bar of light. A glowing spiral arm extends from each end of this bar, both making almost a full turn through the galaxy’s disc before fading out.

The bright object with the four spikes of light is a foreground star inside the Milky Way and only 436 light years away. The bright orange specks inside the spiral arms are likely star forming regions, with the blue indicating gas clouds.

As for the holiday, I’ll have more to say about Memorial Day later today.

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Hubble snaps picture of barred spiral galaxy

10:04 am

A barred spiral galaxy as seen by Hubble
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Cool image time! While NASA celebrates the 35th anniversary of the Hubble Space Telescope with photos from its past, astronomers continue to use it to produce new wonders. The picture to the right, cropped, reduced, and sharpened to post here, was taken by Hubble recently and released today.

NGC 5335 is categorized as a flocculent spiral galaxy with patchy streamers of star formation across its disk. There is a striking lack of well-defined spiral arms that are commonly found among galaxies, including our Milky Way. A notable bar structure slices across the center of the galaxy. The bar channels gas inwards toward the galactic center, fueling star formation. Such bars are dynamic in galaxies and may come and go over two-billion-year intervals. They appear in about 30 percent of observed galaxies, including our Milky Way.

The theorized formation process of that bar is based on computer modeling using the limited data we presently have, and thus carries a great deal of uncertainty.

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NASA re-releases a slew of Hubble images to celebrate its 35th anniversary

9:23 am

Eta Carina, in focus, after 1993 repair mission
Eta Carina, in focus, after 1993 repair mission

As part of its celebration of the telescope’s 35th anniversary, NASA on April 25, 2025 re-released what it called 27 key images from the history of the Hubble Space Telescope.

More than half the images are historical, showing the telescope’s conception by astrophysicist Lyman Spitzer, its construction, its launch in 1990, and its repair in 1993 of its faulty optics. The subsequent sharp astronomical images include only a few of Hubble’s most famous and significant later photographs, including the first Hubble Deep Field, the Hourglass planetary nebula, and the Pillars of Creation snapshot.

What NASA did not include in this collection however was without doubt to those alive at the time after Hubble was finally repaired its most historically significant photo. That picture is to the right. It shows the exploding star Eta Carina as taken by Hubble in 1993 right after its repair.

For the very first time, we had a telescope above the Earth’s fuzzy atmosphere capable of taking sharp in-focus images of the mysteries of the heavens. And for the first time, we could see in this star its actual nature. It wasn’t simply surrounded by a pretty cloud — as all previous ground-based images had suggested — that cloud was formed by eruptions from the star itself. Those earlier eruptions, which had occurred in the previous century, had spewed from the star’s poles, forming two bi-polar clouds that were expanding away from the star most dramatically.

In the three decades since astronomers have used Hubble and its later upgraded cameras to track those expanding clouds, with the most recent photo taken in 2019. Hubble has shown that such massive heavenly objects are not static, but evolving, and with the right high resolution telescopes in space we can track that evolution, in real time.

At the moment no comparable replacement of Hubble is planned, or even on the drawing board. The Einstein space telescope, just launched, will provide magnificent optical images at a slight lower resolution. So will China’s planned Xuntian space telescope, set for launch in 2027. Neither however matches Hubble’s capabilities.

And Hubble is now long past its original lifespan of fifteen years. Though engineers say it is in good shape, this is not true. It presently has only two trustworthy working gyroscopes. To extend its lift, the telescope is operated on only one gyroscope, with a second held back in reserve. When these go, however, so will Hubble.

Meanwhile, the astronomy community continues to put most of its energy in building giant ground-based telescopes that not only cannot match Hubble but are threatened by the coming wave of new communication constellations. Do they rethink their approach and shift to orbital astronomy?

Nah. Instead, the astronomical community demands new powers to to ban those constellations!

Of all people, one would think astronomers more than anyone else would not put their head in the sand. But that’s what they continue to do.

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Twenty years of Hubble data map one long season on Uranus

9:09 am

Uranus over twenty years
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Astronomers using the Hubble Space Telescope multiple times since 2002 have now tracked the changes in its atmosphere during one quarter of its 84 year orbit around the Sun.

The image to the right, reduced and sharpened to post here, shows Hubble’s views across several electromagnetic wavelengths. Uranus’s rotational tilt or inclination is almost 90 degrees, so that it literally rolls on its side as it orbits the Sun. You can see this especially in the bottom two rows. From 2012 to 2022 one pole slowly shifted westward. From the press release:

The Hubble team observed Uranus four times in the 20-year period: in 2002, 2012, 2015, and 2022. They found that, unlike conditions on the gas giants Saturn and Jupiter, methane is not uniformly distributed across Uranus. Instead, it is strongly depleted near the poles. This depletion remained relatively constant over the two decades. However, the aerosol and haze structure changed dramatically, brightening significantly in the northern polar region as the planet approaches its northern summer solstice in 2030.

Since we have not yet observed Uranus over one full year, there are a lot of uncertainties in any conclusions the scientists propose. For one, we don’t know the general atmospheric patterns across all four seasons. For another, any changes seen now might simply be the planet’s weather, random events not directly related to long term climate patterns.

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A galactic ball and spiral interact

9:55 am

A galactic ball and spiral interact
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a study of the star populations in these two interacting galaxies. From the caption:

Arp 105 is a dazzling ongoing merger between an elliptical galaxy and a spiral galaxy drawn together by gravity, characterized by a long, drawn out tidal tail of stars and gas more than 362,000 light-years long. The immense tail, which extends beyond this image from NASA’s Hubble Space Telescope, was pulled from the two galaxies by their gravitational interactions and is embedded with star clusters and dwarf galaxies.

The three blue objects on the outskirts of both galaxies are thought to be active star-forming regions. Whether all three are part of this collision is unclear, as the object on the lower right might simply be a foreground object based on the available data.

What makes this galactic pair so intriguing is that the two galaxies are so different with very different theorized histories. Elliptical galaxies (“the ball”) are thought to be very old, the result of the long term evolution of spirals. You would therefore not think an elliptical would normally interact with a spiral, as their ages are likely so dissimilar.

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A galaxy surrounded by clusters of hot massive stars

8:44 am

A galaxy surrounded by hot massive stars
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Cool image time! The picture to the right, reduced and sharpened to post here, was taken by the Hubble Space Telescope of the galaxy NGC 5042, located about 48 million light years away. The picture combines data from all of Hubble’s available wavelengths from the ultraviolet to the infrared. From the caption:

Perhaps NGC 5042’s most striking feature is its collection of brilliant pink gas clouds that are studded throughout its spiral arms. These flashy clouds are called H II (pronounced “H-two”) regions, and they get their distinctive colour from hydrogen atoms that have been ionised by ultraviolet light. If you look closely at this image, you’ll see that many of these reddish clouds are associated with clumps of blue stars, often appearing to form a shell around the stars.

H II regions arise in expansive clouds of hydrogen gas, and only hot and massive stars [indicated by blue] produce enough high-energy light to create an H II region. Because the stars capable of creating H II regions only live for a few million years — just a blink of an eye in galactic terms — this image represents a fleeting snapshot of life in this galaxy.

The image also includes one star (distinguished by its four diffraction spikes) and a few background galaxies in yellow, the most obvious found in the upper and lower right.

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Hubble takes a close look at one tiny part of the Veil Nebula

12:47 pm

A small section of the Veil Nebula
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Cool image time! The picture to the right, reduced and sharpened to post here, was taken by the Hubble Space Telescope of just one very tiny section of the supernova remnant known as the Veil Nebula, located about 2,400 light years away.

The white dot on the inset (showing the entire Veil Nebula) marks the area covered by this closeup, focused on the one bright section of nebula in the Veil’s southwest quadrant. From the caption:

This nebula is the remnant of a star roughly 20 times as massive as the Sun that exploded about 10 000 years ago. … This view combines images taken in three different filters by Hubble’s Wide Field Camera 3 instrument, highlighting emission from hydrogen, sulphur and oxygen atoms. This image shows just a small fraction of the Veil Nebula; if you could see the entire nebula without the aid of a telescope, it would be as wide as six full Moons placed side by side.

Astronomers have been using Hubble to take periodic pictures of the Veil Nebular since 1994 in order to track changes as these gaseous gossamer strands evolve over time.

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Astronomers find galaxy with nine rings

11:15 am

The Bullseye Galaxy
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Using both the Hubble Space Telescope as well as the Keck telescope in Hawaii, astronomers have discovered a galaxy with nine rings, something never seen before.

The gargantuan galaxy LEDA 1313424 is rippling with nine star-filled rings after an “arrow” — a far smaller blue dwarf galaxy — shot through its heart. Astronomers using Hubble identified eight visible rings, more than previously detected by any telescope in any galaxy, and confirmed a ninth using data from the W. M. Keck Observatory in Hawaii. Previous observations of other galaxies show a maximum of two or three rings.

More information from Keck can be found here.

Keck Observatory and Hubble’s follow-up observations helped the researchers prove which galaxy plunged through the center of the Bullseye — a blue dwarf galaxy to its center-left. This relatively tiny interloper traveled like a dart through the core of the Bullseye about 50 million years ago, leaving rings in its wake like ripples in a pond. A thin trail of gas now links the pair, though they are currently separated by 130,000 light-years.

The Hubble picture is to the right, cropped, reduced, and sharpened to post here. The small blue dwarf galaxy to the left is believed to be the galaxy that plowed through LEDA 1313424 to create the rings. LEDA is itself thought to be two and a half times the size of the Milky Way, making one of the larger known galaxies.

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Hubble’s biggest image yet, of Andromeda

12:14 pm

Andromedia as seen by Hubble
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The image above, cropped and reduced to post here, was taken by the Hubble Space Telescope and shows the Andromeda galaxy, the Milky Way’s nearest spiral galaxy neighbor. The picture however is not one photo, but hundreds taken over the past decade.

This is largest photomosaic ever assembled from Hubble Space Telescope observations. It is a panoramic view of the neighboring Andromeda galaxy, located 2.5 million light-years away. It took over 10 years to make this vast and colorful portrait of the galaxy, requiring over 600 Hubble overlapping snapshots that were challenging to stitch together. The galaxy is so close to us, that in angular size it is six times the apparent diameter of the full Moon, and can be seen with the unaided eye.

Andromeda is not just visible to the naked eye, it is one of the largest objects seen in the sky. If you ever can get to a really dark sky location when it is above and have someone point it out to you (it remains faint), you will be astonished to find that it stretches across the sky the length of about six to eight full moons.

Thus, Hubble literally can’t take a picture of it. Its field of view is much too small. It must take many pictures to assemble a mosaic.

The picture above also hides the data contained in all those images. At the full resolution of each individual picture, Hubble has literally mapped the entire galaxy. Combined with other spectroscopic survey data taken by Hubble, astronomers over time will be able to decipher the galaxy’s makeup to better understand its formation history.

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Hubble captures a nice example of intergalactic microlensing

9:56 am

Micro-lensing at is most distinct
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Cool image time! The picture to the right, cropped to post here, was taken by the Hubble Space Telescope and released this week. I have specifically cropped it to focus on this ringlike feature, as it one of the nicest examples of micro-lensing I have seen. From the caption:

This curious configuration is the result of gravitational lensing, in which the light from a distant object is warped and magnified by the gravity of a massive foreground object, like a galaxy or a cluster of galaxies. Einstein predicted the curving of spacetime by matter in his general theory of relativity, and galaxies seemingly stretched into rings like the one in this image are called Einstein rings.

The lensed galaxy, whose image we see as the ring, lies incredibly far away from Earth: we are seeing it as it was when the Universe was just 2.5 billion years old. The galaxy acting as the gravitational lens itself is likely much closer. A nearly perfect alignment of the two galaxies is necessary to give us this rare kind of glimpse into galactic life in the early days of the Universe.

I am generally a very big skeptic of most astronomical studies that rely on micro-lensing. I don’t deny it happens and has been detected, as in this case. The uncertainties — such as the unknown distance to intervening galaxy that is causing the lensing — always require too many assumptions that make any reliable conclusions difficult.

Nonetheless, this object illustrates the phenomenon perfectly. The light from the distant galaxy is bent around the intervening nearer galaxy so that we that distant galaxy as a ring.

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A fading supernova 650 million light years away

10:18 am

A fading supernova 650 million light years away
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope in March 2024, and shows the fading blue light of a supernova that was first discovered by another survey telescope six weeks earlier. The galaxy, dubbed LEDA 22057, is estimated to be about 650 million light years away.

The supernova is the bright spot in the galaxy’s southeast quadrant near the edge of the galaxy’s bright body. From today’s caption release:

SN 2024PI is classified as a Type Ia supernova. This type of supernova requires a remarkable object called a white dwarf, the crystallised core of a star with a mass less than about eight times the mass of the Sun. When a star of this size uses up the supply of hydrogen in its core, it balloons into a red giant, becoming cool, puffy and luminous. Over time, pulsations and stellar winds cause the star to shed its outer layers, leaving behind a white dwarf and a colourful planetary nebula. White dwarfs can have surface temperatures higher than 100,000 degrees and are extremely dense, packing roughly the mass of the Sun into a sphere the size of Earth.

While nearly all of the stars in the Milky Way will one day evolve into white dwarfs — this is the fate that awaits the Sun some five billion years in the future — not all of them will explode as Type Ia supernovae. For that to happen, the white dwarf must be a member of a binary star system. When a white dwarf syphons material from a stellar partner, the white dwarf can become too massive to support itself. The resulting burst of runaway nuclear fusion destroys the white dwarf in a supernova explosion that can be seen many galaxies away.

The rate in which this supernova fades will help astronomers untangle the processes that cause these gigantic explosions. Though the caption makes it sound as if we know how this happens, we really don’t. There are a lot of assumptions and guesses involved in the description above, based on the limited knowledge astronomers have gathered over the past few centuries looking at many supernovae many millions of light years away.

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Using Hubble to monitor a fading supernova

9:38 am

Barred spiral
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a monitoring program of the fading supernova that occurred in this galaxy in 2014, 60 million light years away. I have added a white dot to indicate the approximate location [pdf] of that supernova, as it is now too dim to see clearly in the original image. From the caption:

Researchers have determined that SN 2014cx was a Type IIP supernova. The “Type II” classification means that the exploding star was a supergiant at least eight times as massive as the Sun. The “P” stands for plateau, meaning that after the light from the supernova began to fade, the level reached a plateau, remaining at the same brightness for several weeks or months before fading further. This type of supernova occurs when a massive star can no longer produce enough energy in its core to stave off the crushing pressure of gravity. SN 2014cx’s progenitor star is estimated to have been ten times more massive than the Sun and hundreds of times as wide. Though it has long since dimmed from its initial brilliance, researchers are still keeping tabs on this exploded star, not least through the Hubble observing programme which produced this image.

The blue regions in the galaxy’s periphery suggest younger stars, while the gold color in the interior suggests an older population.

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A galactic eye in heaven

12:30 pm

A galactic eye in space
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Cool image time! The picture to the right, reduced and sharpened to post here, was taken by the Hubble Space Telescope as part of a project to study the star formation processes over time in this galaxy, located about 76 million light years away.

A prominent bar of stars stretches across the centre of this galaxy, and spiral arms emerge from each end of the bar. Because NGC 2566 appears tilted from our perspective, its disc takes on an almond shape, giving the galaxy the appearance of a cosmic eye.

As NGC 2566 gazes at us, astronomers gaze right back, using Hubble to survey the galaxy’s star clusters and star-forming regions. The Hubble data are especially valuable for studying stars that are just a few million years old; these stars are bright at the ultraviolet and visible wavelengths to which Hubble is sensitive. Using these data, researchers will measure the ages of NGC 2566’s stars, helping to piece together the timeline of the galaxy’s star formation and the exchange of gas between star-forming clouds and stars themselves.

To get the full picture, astronomers have also obtained infrared data from the Webb Space Telescope and millimeter/submillimeter radio wavelength data from the ALMA telescope.

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Hubble takes a different look at quasar 3C 273

10:25 am

Hubble's different views of 3C 273
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One of the most studied objects in the sky is the quasar 3C 273, located about 2.5 billion light years away and the first quasar ever to be identified, in 1963. What makes it especially interesting is the 300,000-light-year-long jet that shoots out from it.

Astronomers have now used the Hubble Space Telescope to take a different view of 3C 273, using the telescope’s coronograph to block the central bright light so that the surrounding dimmer features can be seen. The two images to the right, reduced and sharpened to post here, show what this new image (bottom) reveals when compared to an earlier Hubble image (top).

The new Hubble views of the environment around the quasar show a lot of “weird things,” according to Bin Ren of the Côte d’Azur Observatory and Université Côte d’Azur in Nice, France. “We’ve got a few blobs of different sizes, and a mysterious L-shaped filamentary structure. This is all within 16,000 light-years of the black hole.”

Some of the objects could be small satellite galaxies falling into the black hole, and so they could offer the materials that will accrete onto the central supermassive black hole, powering the bright lighthouse.

What makes this observation even more outstanding is that the image was produced by using Hubble’s Space Telescope Imaging Spectrograph (STIS) as the coronograph to block the bright center of 3C 273. This improvisation of STIS has been done many times before, but it remains a great example of clever thinking by the astronomers who use Hubble.

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New stars shaped by old stars

8:50 am

New stars shaped by old stars
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a study focused on looking at star formation in nearby galaxies. From the caption:

Evidence of star formation is scattered all around NGC 1637, if you know where to look. The galaxy’s spiral arms are dotted with what appear to be pink clouds, many of which are accompanied by bright blue stars. The pinkish colour comes from hydrogen atoms that have been excited by ultraviolet light from young, massive stars. This contrasts with the warm yellow glow of the galaxy’s centre, which is home to a densely packed collection of older, redder stars.

The stars that set their birthplaces aglow are comparatively short-lived, and many of these stars will explode as supernovae just a few million years after they’re born. In 1999, NGC 1637 played host to a supernova, pithily named SN 1999EM, that was lauded as the brightest supernova seen that year. When a massive star expires as a supernova, the explosion outshines its entire home galaxy for a short time. While a supernova marks the end of a star’s life, it can also jump start the formation of new stars by compressing nearby clouds of gas, beginning the stellar lifecycle anew.

This galaxy is one worth keeping an eye on for supernovae, since every one of those blue stars has the potential of erupting.

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Hubble vs Webb, or why the universe’s secrets can only be uncovered by looking at things in many wavelengths

11:15 am

Hubble view of Sombrero galaxy
Click for original image.

Time for two cool images of the same galaxy! The picture above shows the Sombrero Galaxy as taken by the Hubble Space Telescope in 2003. The picture below is that same galaxy as seen by the Webb Space Telescope in the mid-infrared using false colors. From the press release:

In Webb’s mid-infrared view of the Sombrero galaxy, also known as Messier 104 (M104), the signature, glowing core seen in visible-light images does not shine, and instead a smooth inner disk is revealed. The sharp resolution of Webb’s MIRI (Mid-Infrared Instrument) also brings into focus details of the galaxy’s outer ring, providing insights into how the dust, an essential building block for astronomical objects in the universe, is distributed. The galaxy’s outer ring, which appeared smooth like a blanket in imaging from NASA’s retired Spitzer Space Telescope, shows intricate clumps in the infrared for the first time.

Researchers say the clumpy nature of the dust, where MIRI detects carbon-containing molecules called polycyclic aromatic hydrocarbons, can indicate the presence of young star-forming regions. However, unlike some galaxies studied with Webb … the Sombrero galaxy is not a particular hotbed of star formation. The rings of the Sombrero galaxy produce less than one solar mass of stars per year, in comparison to the Milky Way’s roughly two solar masses a year. Even the supermassive black hole, also known as an active galactic nucleus, at the center of the Sombrero galaxy is rather docile, even at a hefty 9-billion-solar masses. It’s classified as a low luminosity active galactic nucleus, slowly snacking on infalling material from the galaxy, while sending off a bright, relatively small, jet.

In infrared the galaxy’s middle bulge of stars practically vanishes, exposing the weak star-forming regions along galaxy’s disk.

Both images illustrate the challenge the universe presents us in understanding it. Basic facts are often and in fact almost always not evident to the naked eye. We always need to look deeper, in ways that at first do not seem obvious. This is why it is always dangerous to theorize with certainty any explanation too soon, as later data will always change that explanation. You can come up with an hypothesis, but you should always add the caveat that you really don’t know.

By the way, this concept applies not just to science. Having absolute certainty in anything will almost always cause you to look like a fool later. Better to always question yourself, because that will make it easier for you to find a better answer, sooner.

We need only look at the idiotic “mainstream press” during the months leading up to the November election to have an example of someone with certainty who is now exposed as an obvious fool.

The Sombrero Galaxy as seen by Webb
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A spiral galaxy as seen from the side

9:36 am

A spiral galaxy seen from the side
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Cool image time! The picture to the right, reduced to post here, was taken by the Hubble Space Telescope of what is believed to be a spiral galaxy seen edge-on. The galaxy itself is estimated to be 150 million light years away, and this view highlights two major features, the dust lanes that run along the galaxy’s length and its distinct central nucleus, bulging out from the galaxy’s flat plain.

The way this image was produced however is intriguing on its own:

Like most of the full-colour Hubble images released by ESA/Hubble, this image is a composite, made up of several individual snapshots taken by Hubble at different times and capturing different wavelengths of light. … A notable aspect of this image is that the two sets of Hubble data used were collected 23 years apart, in 2000 and 2023! Hubble’s longevity doesn’t just afford us the ability to produce new and better images of old targets; it also provides a long-term archive of data which only becomes more and more useful to astronomers.

All told, four Hubble data sets were used to produce the picture.

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A 2017 supernova as spotted by Hubble

11:20 am

Before and after of galaxy with supernova
Click for original image.

Cool image time! The pictures to the right were both compiled from photos taken by the Hubble Space Telescope, with the bottom annotated to indicate the location of a 2017 supernova that was not visible in the earlier 2005 picture.

In this collage two images of the spiral galaxy NGC 1672 are compared: one showing supernova SN 2017GAX as a small green dot, and the other without. The difference between the images is that both have been created by processing multiple individual Hubble images, each taken to capture a specific wavelength of visible light, and combining them to make a full-colour image. In one of those filtered frames, taken in 2017, the fading supernova is still visible

NGC 1672 is considered a barred spiral galaxy. Located an estimated 52 million light years away, the 2017 supernovae was not the last detected within it. In 2022 a second supernovae occurred. That’s two supernovae within five years. Meanwhile the Milky Way has not seen a supernova in more than four centuries.

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Scientists use Hubble and Webb to confirm there are as yet no planets forming in Vega’s accretion disk

11:16 am

Hubble and Webb images of Vega's accretion disk
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Using both the Hubble and Webb space telescopes, scientists have now confirmed, to their surprise, that the accretioni disk that surrounds the nearby star Vega is very smooth with almost no gaps, and thus apparently has not new exoplanets forming within it.

The two pictures to the right, cropped and reduced to post here, come from two different papers. The Hubble paper is here [pdf] while the Webb paper is here [pdf]. From the press release:

Webb sees the infrared glow from a disk of particles the size of sand swirling around the sizzling blue-white star that is 40 times brighter than our Sun. Hubble captures an outer halo of this disk, with particles no bigger than the consistency of smoke that are reflecting starlight.

The distribution of dust in the Vega debris disk is layered because the pressure of starlight pushes out the smaller grains faster than larger grains. “Different types of physics will locate different-sized particles at different locations,” said Schuyler Wolff of the University of Arizona team, lead author of the paper presenting the Hubble findings. “The fact that we’re seeing dust particle sizes sorted out can help us understand the underlying dynamics in circumstellar disks.”

The Vega disk does have a subtle gap, around 60 AU (astronomical units) from the star (twice the distance of Neptune from the Sun), but otherwise is very smooth all the way in until it is lost in the glare of the star. This shows that there are no planets down at least to Neptune-mass circulating in large orbits, as in our solar system, say the researchers.

At the moment astronomers consider the very smooth accretion disk surrounding Vega to be rare and exception to the rule, with most debris disks having gaps that suggest the presence of newly formed exoplanets within them. That Vega breaks the rule however suggests the rule might not be right in the first place.

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Post-collision images of two galaxies

10:56 am

Post-collision imagery by Hubble and Webb
Click for original image.

Using both the Hubble and Webb space telescopes, astronomers have now produced multi-wavelength images of the galaxies NGC 2207and IC 2163, as shown to the right.

Millions of years ago the smaller galaxy, IC 2163, grazed against the larger, NGC 2207, resulting today in increased star formation in both galaxies, indicated by blue in the Hubble photo. From the caption of the combined images:

Combined, they are estimated to form the equivalent of two dozen new stars that are the size of the Sun annually. Our Milky Way galaxy forms the equivalent of two or three new Sun-like stars per year. Both galaxies have hosted seven known supernovae, each of which may have cleared space in their arms, rearranging gas and dust that later cooled, and allowed many new stars to form.

The two images to the left leaves the Hubble and Webb separate, making it easier to see the different features the different wavelengths reveal. From this caption:

In Hubble’s image, the star-filled spiral arms glow brightly in blue, and the galaxies’ cores in orange. Both galaxies are covered in dark brown dust lanes, which obscure the view of IC 2163’s core at left. In Webb’s image, cold dust takes centre stage, casting the galaxies’ arms in white. Areas where stars are still deeply embedded in the dust appear pink. Other pink dots may be objects that lie well behind these galaxies, including active supermassive black holes known as quasars.

The largest and brightest pink area in the Webb image, on the bottom right and a blue patch in the Hubble image, is where a strong cluster of star formation is presently occurring.

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A galaxy squashed as it plows its way through the intergalactic medium

9:21 am

A galaxy squashed by a vacuum
Click for original image.

Time for another cool image on this relatively slow day in the space news business. The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope and released today by the European Space Agency’s press department. From the caption:

Appearances can be deceiving with objects so far from Earth — IC 3225 itself [the galaxy to the right] is about 100 million light-years away — but the galaxy’s location suggests some causes for this active scene, because IC 3225 is one of over 1300 members of the Virgo galaxy cluster. The density of galaxies in the Virgo cluster creates a rich field of hot gas between them, the so-called ‘intracluster medium’, while the cluster’s extreme mass has its galaxies careening around its centre in some very fast orbits. Ramming through the thick intracluster medium, especially close to the cluster’s centre, places an enormous ‘ram pressure’ on the moving galaxies that strips gas out of them as they go.

IC 3225 is not so close to the cluster core right now, but astronomers have deduced that it has undergone this ram pressure stripping in the past. The galaxy looks as though it’s been impacted by this: it is compressed on one side and there has been noticeably more star formation on this leading edge, while the opposite end is stretched out of shape. Being in such a crowded field, a close call with another galaxy could also have tugged on IC 3225 and created this shape. The sight of this distorted galaxy is a reminder of the incredible forces at work on astronomical scales, which can move and reshape even entire galaxies!

What makes the impact on this galaxy of that intercluster medium so astonishing is that medium is so relatively empty of material. The space between galaxies in the Virgo cluster is in all intents and purposes a vacuum far more empty than any that we can create in a chamber on Earth. And yet it was enough to distort this galaxy and cause star formation on the galaxy’s leading edge.

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A water sprinkler in space

11:42 am

A sprinkler in space

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a long term program to monitor changes in the R Aquarii binary star system, located about 700 light years away.

R Aquarii belongs to a class of double stars called symbiotic stars. The primary star is an aging red giant and its companion is a compact burned-out star known as a white dwarf. The red giant primary star is classified as a Mira variable that is over 400 times larger than our Sun. The bloated monster star pulsates, changes temperature, and varies in brightness by a factor of 750 times over a roughly 390-day period. At its peak the star is blinding at nearly 5,000 times our Sun’s brightness.

When the white dwarf star swings closest to the red giant along its 44-year orbital period, it gravitationally siphons off hydrogen gas. This material accumulates on the dwarf star’s surface until it undergoes spontaneous nuclear fusion, making that surface explode like a gigantic hydrogen bomb. After the outburst, the fueling cycle begins again.

This outburst ejects geyser-like filaments shooting out from the core, forming weird loops and trails as the plasma emerges in streamers. The plasma is twisted by the force of the explosion and channeled upwards and outwards by strong magnetic fields. The outflow appears to bend back on itself into a spiral pattern. The plasma is shooting into space over 1 million miles per hour – fast enough to travel from Earth to the Moon in 15 minutes! The filaments are glowing in visible light because they are energized by blistering radiation from the stellar duo.

The press release likens these filaments to the spray thrown out by a water sprinkler, and I must say that’s an apt description.

Since 2014 scientists have taken regular pictures of R Aquarii, and found that the central structures have been changing in a perceptible manner, despite their gigantic size. Below is a movie created from five photos taken from 2014 to 2023.
» Read more

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Jupiter’s Great Red Spot appears to jiggle like Jello on a 90-day cycle

9:07 am

Jupiter as seen by Hubble over time
Click for original image.

Using the Hubble Space Telescope to photograph Jupiter’s Great Red Spot repeatedly over a four month period from December 2023 to March 2024 scientists have detected a 90-day cycle in which the spot oscillated in shape, shaking like Jello.

“While we knew its motion varies slightly in its longitude, we didn’t expect to see the size oscillate. As far as we know, it’s not been identified before,” said Amy Simon of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, lead author of the science paper published in The Planetary Science Journal. “This is really the first time we’ve had the proper imaging cadence of the GRS. With Hubble’s high resolution we can say that the GRS is definitively squeezing in and out at the same time as it moves faster and slower. That was very unexpected, and at present there are no hydrodynamic explanations.”

The four images to the right are some of those observations. For a full movie showing the changes over ninety days, go here.

The scientists also predict that though the spot has been shrinking for decades, they expect that shrinkage to stop once the spot size no longer extends beyond the jet stream band within which it sits. At that point the different jet streams in the upper and lower bands will hold the spot in place and its size will stabilize.

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The jet 3,000 light years long that causes nearby stars to explode

10:48 am

The jet from M87
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Cool image time! The picture to the left, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope of the giant eliptical galaxy M87, known for more than a century by astronomers for the jet of gas that points outward from its center. Astronomers now know that this jet is produced by a supermassive black hole in the center of M87, weighing 6.5 billion times the mass of our Sun.

The blowtorch-like jet seems to cause stars to erupt along its trajectory. These novae are not caught inside the jet, but are apparently in a dangerous neighbourhood nearby. During a recent 9-month survey, astronomers using Hubble found twice as many of these novae going off near the jet as elsewhere in the galaxy. The galaxy is the home of several trillion stars and thousands of star-like globular star clusters.

M87 is considered an old galaxy, but its entire formation process remains uncertain.

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Webb takes an infrared look at a galaxy looked at by Hubble

12:21 pm

Comparing Hubble with Webb
For original images go here and here.

Cool image time! The bottom picture on the right, cropped to post here, is a just released false color infrared image of the galaxy Arp 107, taken by the Webb Space Telescope. The picture at the top is a previously released optical image taken by the Hubble Space Telescope and featured as a cool image back in September 2023. The Hubble image was taken as part of a survey project to photograph the entire Arp catalog of 338 “peculiar galaxies,” put together by astronomer Halton Arp in 1966. In this case Arp 107 is peculiar because it is actually two galaxies in the process of merging. It is also peculiar because the galaxy on the left has an active galactic nuclei (AGN), where a supermassive black hole is sucking up material and thus emitting a lot of energy.

The Webb infrared image was taken to supplement that optical image. The blue spiral arms indicate dust and star-forming regions. The bright orange object in the center of the galaxy is that AGN, clearly defined by Webb’s infrared camera.

When I posted the Hubble image in 2023, I noted that “if you ignore the blue whorls of the left galaxy, the two bright cores of these merging galaxies are about the same size.” In the Webb image the two cores still appear about the same size, but in the infrared they produce emissions in decidedly different wavelengths, as shown by the different false colors of orange and blue. The core of the galaxy on the right is dust filled and forming stars, while the core of the left galaxy appears to have less dust with all of its emissions resulting from the energy produced by the material being pulled into the supermassive black hole.

The universe is very active and changing, but to understand that process we humans have to look at everything across the entire electromagnetic spectrum, not just in the optical wavelengths our eyes see.

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What the Milky Way would look like if it was presently a star forming powerhouse

9:15 am

A galaxy as seen by Hubble and Webb
For the original images go here and here.

Cool image time! The two pictures to the right, taken respectively by the Hubble and Webb space telescopes of the same galaxy, shows us many different features of a barred galaxy, located about 35 million light years away. From the caption for the Hubble image:

This picture is composed of a whopping ten different images taken by the Hubble Space Telescope, each filtered to collect light from a specific wavelength or range of wavelengths. It spans Hubble’s sensitivity to light, from ultraviolet around 275 nanometres through blue, green and red to near-infrared at 1600 nanometres. This allows information about many different astrophysical processes in the galaxy to be recorded: a notable example is the red 656-nanometre filter used here. Hydrogen atoms which get ionised can emit light at this particular wavelength, called H-alpha emission. New stars forming in a molecular cloud, made mostly of hydrogen gas, emit copious amounts of ultraviolet light which is absorbed by the cloud, but which ionises it and causes it to glow with this H-alpha light.

Therefore, filtering to detect only this light provides a reliable means to detect areas of star formation (called H II regions), shown in this image by the bright red and pink colours of the blossoming patches filling NGC 1559’s spiral arms.

The Z-shaped blue indicates the stars and its most distinct spiral arms. Astronomers presently believe that the Milky Way is also a barred spiral like this, though its star-forming regions are thought to be far less extensive and distinct.

The Webb infrared image matches the Hubble data, with the false color blue indicating the near-infrared and the false color red the mid-infrared. As with the Hubble picture, the red indicates the galaxy’s extensive star forming regions.

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