Baby stars illuminating the dust that surrounds them

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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The subject of this week’s Hubble Picture of the Week is a reflection nebula, identified as GN 04.32.8. Reflection nebulae are clouds of dust in space that don’t emit their own light, as other nebulae do. Instead, the light from nearby stars hits and scatters off their dust, lighting them up. Because of the way the light scatters, many reflection nebulae tend to appear blue, GN 04.32.8 included. 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. [Image Description: A long, smoky, greyish-blue cloud in the centre of the image curves in an arc around three bright stars, each with long cross-shaped diffraction spikes. The cloud is lit more brightly on the inner side facing the stars, and fades into the dark background on the outer side. A few other stars and points of light surround the cloud: one small star below it has a dark band crossing its centre.]

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Astronomers discover a perfect sphere in radio

Radio object Teleios

Using the array of radio dishes dubbed the Australian Square Kilometre Array, astronomers have made the serendipitous discovery of what appears to be a perfect sphere of radio emissions tens of light years in diameter and tens of thousands of light years away and near the galactic center.

The scientists have dubbed the object Teleios, Greek for ‘complete’ or ‘perfect’. The image to the right is that radio image. Though the astronomers posit that it must have been formed from a supernova explosion, there are problems with that conclusion. From their paper [pdf]:

Unfortunately, all examined scenarios have their challenges, and no definitive Supernova origin type can be established at this stage. Remarkably, Teleios has retained its symmetrical shape as it aged even to such a diameter, suggesting expansion into a rarefied and isotropic ambient medium. The low radio surface brightness and the lack of pronounced polarisation can be explained by a high level of ambient rotation measure (RM), with the largest RM being observed at Teleios’s centre.

In other words, this object only emits in radio waves, is not visible in optical or other wavelengths as expected, and thus doesn’t really fit with any theories describing the evolution of supernova explosions. Yet its nature fits all other possible known space objects even less, such as planetary nebulae, nova remnants, Wolf-Rayet stars, or even super-bubbles of empty space (such as the Local Bubble the solar system is presently in).

Baffled, the scientists even considered the possibility that they had discovered an artificially built Dyson Sphere, but dismissed that idea because Teleios emits no infrared near its boundaries, as such a sphere is expected to do.

At present the best theory remains a supernova remnant, though this remains a poor solution at best.

Hat tip to reader (and my former editor at UPI) Phil Berardelli.

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

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.

A telescope picture of blackness

A dust cloud in space
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was released today by the science team running the Dark Energy Camera on the Blanco 4-meter telescope in Chile.

This winding, shadowy form, accentuated by a densely-packed starry background, is the Circinus West molecular cloud — a region rich in gas and dust and known for its host of newly formed stars. Molecular Clouds, the cradles of star formation, are interstellar clouds that are so dense and cold that atoms within them bond with each other to form molecules. Some, such as Circinus West, are so dense that light cannot pass through, giving them a dark, mottled appearance and earning them the name dark nebulae. The cloud’s flourishing population of young stars has offered astronomers a wealth of insight into the processes driving star formation and molecular cloud evolution.

…Circinus West is known for harboring dozens of young stellar objects — stars that are in their early stages of development. Despite being shrouded in dense gas and dust, these infant stars make themselves known. Zooming in, various clues to their presence can be seen dotted throughout Circinus West’s snaking tendrils.

The cloud is about 2,500 light years away and is estimated to be about 180 light years across. Scientists estimate the mass in the cloud to be about 250,000 times that of the Sun.

No one however would ever even know this cloud existed if it wasn’t back dropped by thick field of stars behind it.

The structure of a ringed planetary nebula revealed in the infrared

A planetary nebula as seen by Webb
Click for original image.

Cool image time! Using the mid-infrared camera on the Webb Space Telescope, astronomers have been able to image in false colors the ringed structure surrounding a dying star about 1,500 light years away.

The nebula’s two rings are unevenly illuminated in Webb’s observations, appearing more diffuse at bottom left and top right. They also look fuzzy, or textured. “We think the rings are primarily made up of very small dust grains,” Ressler said. “When those grains are hit by ultraviolet light from the white dwarf star, they heat up ever so slightly, which we think makes them just warm enough to be detected by Webb in mid-infrared light.”

In addition to dust, the telescope also revealed oxygen in its clumpy pink center, particularly at the edges of the bubbles or holes.

NGC 1514 is also notable for what is absent. Carbon and more complex versions of it, smoke-like material known as polycyclic aromatic hydrocarbons, are common in planetary nebulae (expanding shells of glowing gas expelled by stars late in their lives). Neither were detected in NGC 1514. More complex molecules might not have had time to form due to the orbit of the two central stars, which mixed up the ejected material.

Though this false-color image of a planetary nebular is hardly ground-breaking (Hubble has been producing such pictures for decades), Webb’s better infrared data, in higher resolution, will help astronomers untangle the nebula’s complex geography. It remains however a question whether the improved capabilities of Webb were worth its $10 billion-plus cost. For that money NASA could have built and launched many different astronomical missions in the past two decades, many of which would have been able to match this data for far less.

Scientists: X-rays from the Helix Nebula caused by the destruction of a planet

A composite image of the Helix Nebula
A composite image of the Helix Nebula, combining data
from multiple ground- and space-based telescopes.
Click for original image.

Using data collected by multiple ground-bases and space telescopes over decades, scientists now think the previously unexplained high energy X-rays coming from the white dwarf star at the center of the Helix Nebula are caused by the destruction of a Jupiter-sized exoplanet.

The besieged planet could have initially been a considerable distance from the white dwarf but then migrated inwards by interacting with the gravity of other planets in the system. Once it approached close enough to the white dwarf, the gravity of the star would have partially or completely torn the planet apart. “The mysterious signal we’ve been seeing could be caused by the debris from the shattered planet falling onto the white dwarf’s surface, and being heated to glow in X-rays,” said co-author Martin Guerrero of The Institute of Astrophysics of Andalusia in Spain. “If confirmed, this would be the first case of a planet seen to be destroyed by the central star in a planetary nebula.”

The study shows that the X-ray signal from the white dwarf has remained approximately constant in brightness between 1992, 1999, and 2002 (with observations by ROSAT, Chandra and XMM respectively). The data, however, suggests there may be a subtle, regular change in the X-ray signal every 2.9 hours, providing evidence for the remains of a planet exceptionally close to the white dwarf.

You can read the original paper here. The Helix Nebula is about 650 light years away, and is one of the most studied planetary nebula, believed to have formed when the central star collapsed into a white dwarf.

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

A small section of the Veil Nebula
Click for original image.

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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In this NASA/ESA Hubble Space Telescope Picture of the Week, Hubble has once again lifted the veil on a famous — and frequently photographed — supernova remnant: the Veil Nebula. This nebula is the remnant of a star roughly 20 times as massive as the Sun that exploded about 10 000 years ago. Situated about 2400 light-years away in the constellation Cygnus, this photogenic nebula made an appearance as the Picture of the Week previously in 2021. 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. Look in the sidebar of this page to see this image superimposed on its location in the sky, and try zooming out to compare the size of the full nebula! Although this image captures the Veil Nebula at just a single point in time, it will help researchers understand how the supernova remnant has evolved over decades. Combining this snapshot with Hubble observations from 1994 will reveal the motion of individual knots and filaments of gas over that span of time, enhancing our understanding of this stunning nebula. [Image Description: A colourful, glowing nebula that reaches beyond the top and bottom of the image. It is made of translucent clouds of gas: wispy and thin with hard edges in some places, and puffy and opaque in others. Blue, red and yellow colours mix together, showing light emitted by different types of atoms in the hot gas. Bright and pointlike stars are scattered across the nebula. The background is black.]

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A rose in space

A rose in space
Click for original image.

Cool image time! Using the Gemini South telescope in Chile, astronomers have taken a very beautiful picture, cropped, reduced, and sharpened to post here, of a nebula dubbed LH 88 that surrounds a star cluster and is located 160,000 light years away in the Large Magellanic Cloud.

The bright stars seen in the image are widely separated, but their motions through space are similar, indicating that they have a common origin. The layered nebulous structures in LH 88 are the remnants of stars that have already died. The delicate leaves of the rose were formed by both the shockwaves from supernovae and the stellar winds of the O and B stars.

The intense radiation of these super giant O and B stars — that burn fast and explode as supernova after only a few million years of life — not only shapes the nebula, it lights the nebula’s different atoms and molecules in different colors, with red/orange representing hydrogen and blue oxygen. The white areas indicate a mixture of both.

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Displaying wispy layers of red, orange and yellow, the nebula encasing NGC 2040 resembles a vibrant rose in this image captured by the Gemini South telescope, one half of the International Gemini Observatory, which is supported in part by the U.S. National Science Foundation and operated by NSF NOIRLab. This nebulous flower showcases the dramatic story of stellar life, death and rebirth.

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December 31, 2024 Quick space links

Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.

Before we get to the links, I think it is time to send a hearty Happy New Year to all my readers. Thank you again for making 2024 the best year so far. And best of all, next year should even be better!

  • SpaceX touts the completion of its fifth manned Dragon capsule
    The tweet says this will be the last manned Dragon capsule, but Jay suspects that means the “last built in California.” He thinks future capsules will be built in Florida, the work driven from California due to its almost communist government. I’m not so sure. SpaceX remember is hoping Starship will replace the capsules in the future. Why build more in that case?

A fading supernova 650 million light years away

A fading supernova 650 million light years away
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 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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This NASA/ESA Hubble Space Telescope Picture of the Week features the galaxy LEDA 22057, which is located about 650 million light-years away in the constellation Gemini. Like the subject of last week’s Picture of the Week, LEDA 22057 is the site of a supernova explosion. This particular supernova, named SN 2024PI, was discovered by an automated survey in January 2024. The survey covers the entire northern half of the night sky every two days and has catalogued more than 10 000 supernovae. The supernova is visible in this image: located just down and to the right of the galactic nucleus, the pale blue dot of SN 2024PI stands out against the galaxy’s ghostly spiral arms. This image was taken about a month and a half after the supernova was discovered, so the supernova is seen here many times fainter than its maximum brilliance. 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. [Image Description: A spiral galaxy with two thin, slowly-curving arms, one fainter than the other, coming off the tips of a bright, oval-shaped core region. The disc of the galaxy is also oval-shaped and filled with fuzzy dust under the arms. It has some bright spots where stars are concentrated, especially along the arms. The core has a white glow in the centre and thick bands of gas around it. A supernova is visible as a pale blue dot near the core.]

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What kind of astronomical object is this? It doesn’t look quite like the kinds of galaxies, nebulae, star clusters or galaxy clusters which Hubble normally brings us images of. In fact, this is a spiral galaxy, named UGC 10043 — we just happen to be seeing it directly from the side! Located roughly 150 million light-years from Earth in the constellation Serpens, UGC 10043 is one of the somewhat rare spiral galaxies that are seen edge-on. From this point of view, we see the galaxy’s disc as a sharp line through space, overlain with a prominent dust lane. This dust is spread across the spiral arms of UGC 10043, but it looks very thick and cloudy when viewed from the side. You can even see the lights of some active star-forming regions in the arms, shining out from behind the dust. Strikingly, we can also see that the centre of the galaxy sports a glowing, almost egg-shaped ‘bulge’, rising far above and below the disc. All spiral galaxies have a bulge like this one as part of their structure, containing stars that orbit the galactic centre on paths above and below the whirling disc; it’s a feature that isn’t normally obvious in pictures of galaxies. The unusually large size of this bulge compared to the galaxy’s disc is possibly thanks to UGC 10043 siphoning material from a nearby dwarf galaxy. This may also be why the disc is warped, bending up at one end and down at the other. 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. You can see the exact images used in the sidebar on this page. 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. [Image Description: A spiral galaxy seen directly from the side, such that its disc looks like a narrow diagonal band across the image. A band of dark dust covers the disc in the centre most of the way out to the ends, and the disc glows around that. In the centre a whitish circle of light bulges out above and below the disc. The tips of the disc are a bit bent. The background is black and mostly empty.] Links Pan of UGC 10043

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November 8, 2024 Quick space links

Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.

My posting continues to be light for numerous reasons. Though all is generally well, the present condition of my eyes sometimes makes reading and writing difficult. Today was a particularly bad day, the double vision and blind spot making if very hard to see the words I put on the screen. Sorry.

Note too that next week posting will also be light, because I have relatives visiting from Israel and I am taking them to see the Grand Canyon for their first time. I might be able to post, but can make no guarantees.

My apologizes to my loyal readers for all this. but sometimes life gets in the way.

October 25, 2424 Quick space links

Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.

  • NASA delays decision of cutting budgets for both Chandra and Hubble
    No surprise, The announced cuts were originally announced to apply pressure on Congress to fund both telescopes. With the election upcoming the agency wants to get Congress on their side. Cutting these popular telescopes just before the election will not servie its insterets.

Webb data suggests the possibility of ice and hydrated minerals on surface of Psyche

Using the Webb Space Telescope, astronomers have detected evidence of hydrated minerals and even possibly a very tiny amount of water ice on the surface of the metal asteroid Psyche.

The Webb data point to hydroxyl and perhaps water on Psyche’s surface. The hydrated minerals could result from external sources, including impactors. If the hydration is native or endogenous, then Psyche may have a different evolutionary history than current models suggest. “Asteroids are leftovers from the planetary formation process, so their compositions vary depending on where they formed in the solar nebula,” said SwRI’s Dr. Anicia Arredondo, another co-author. “Hydration that is endogenous could suggest that Psyche is not the remnant core of a protoplanet. Instead, it could suggest that Psyche originated beyond the ‘snow line,’ the minimum distance from the Sun where protoplanetary disc temperatures are low enough for volatile compounds to condense into solids, before migrating to the outer main belt.”

However, the paper found the variability in the strength of the hydration features across the observations implies a heterogeneous distribution of hydrated minerals. This variability suggests a complex surface history that could be explained by impacts from carbonaceous chondrite asteroids thought to be very hydrated.

You can read the research paper here [pdf]. The actual amount of water possible is at most 39 parts per million and is also an order of magnitude lower than that found on the Moon, which strongly suggests that it comes from outside sources, such as impacts from other asteroids, not from the inherent geological history of Psyche itself.

The uncertainties of this research, which are large, which should be resolved when the probe Psyche, launched last year, reaches the asteroid Psyche in August 2029.

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This Hubble Picture of the Week features the galaxy LEDA 857074, located in the constellation Eridanus. LEDA 857074 is a barred spiral galaxy, with partially broken spiral arms. It also has a particularly bright spot right in its bar: this is a supernova snapped by Hubble, named SN 2022ADQZ, and quite relevant to this Picture of the Week. The NASA/ESA Hubble Space Telescope has observed a vast range of celestial objects, from galaxies, to nebulae, to star clusters, to planets in the Solar System and beyond. Observing programmes usually seek to gather data so that astronomers can answer a specific question. Naturally, this means most scheduled observations target an object that astronomers have already researched. Some are famous, like the Crab Nebula or the globular cluster Omega Centauri; others might not be so well known to the public, but still be featured in hundreds of scientific papers, such as the Spider Galaxy or NGC 4753. Not so with this galaxy: LEDA 857074 is named in fewer than five papers, one of which is the Lyon-Meudon Extragalactic Database itself. Virtually no data have been recorded about it, other than its position: since its discovery, it simply hasn’t been studied. So how did it attract the gaze of the legendary Hubble? The supernova is the answer — SN 2022ADQZ was detected by an automated survey in late 2022, and led to Hubble being pointed at its host galaxy, LEDA 857074, in early 2023. Astronomers have catalogued millions of galaxies, so while today tens of thousands of supernovae are detected annually, the chance that one is spotted in any particular galaxy is slim. We also do not know how actively LEDA 857074 is forming stars, and therefore how often it might host a supernova. This galaxy is therefore an unlikely and lucky target of Hubble, thanks to this supernova shining a spotlight on it! It now joins the ranks of many more famous celestial objects, with its own Hubble image. [Image Description: A close-in view of a barred spiral galaxy. The bright, glowing bar crosses the centre of the galaxy, with blurred spiral arms curving away from its ends and continuing out of view. It’s surrounded by bright points of light that indicate stars and galaxies. The galaxy also hosts a bright supernova in its central bar.] Links Pan of LEDA 857074

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In this week’s Hubble Picture of the Week we are treated to a wonderfully detailed snapshot of NGC 3430. A spiral galaxy, it lies 100 million light-years from Earth in the constellation Leo Minor. Several other galaxies are located relatively nearby to this one, just out of frame; one is close enough that gravitational interaction is driving some star formation in NGC 3430.  That NGC 3430 is such a fine example of a galactic spiral may be why it ended up as part of the sample that Edwin Hubble used to define his classification of galaxies. Namesake of the Hubble Space Telescope, in 1926 he authored a paper which classified some four hundred galaxies by their appearance — as either spiral, barred spiral, lenticular, elliptical or irregular. This straightforward typology proved immensely influential, and the modern, more detailed schemes that astronomers use today are still based on it. NGC 3430 itself is an SAc galaxy, a spiral lacking a central bar with open, clearly-defined arms. At the time of Hubble’s paper, the study of galaxies in their own right was in its infancy. With the benefit of Henrietta Leavitt’s work on Cepheid variable stars, Hubble had only a couple of years before settled the debate about whether these ‘nebulae’, as they were called then, were situated within our galaxy or were distant and independent. He himself referred to ‘extragalactic nebulae’ in his paper, indicating that they lay beyond the Milky Way galaxy. Once it became clear that these distant objects were very different from actual nebulae, the favoured term for a while was the quite poetic ‘island universe’. While NGC 3430 may look as if it still deserves this moniker, today we simply call it and the objects like it a ‘galaxy’. [Image Description: A spiral galaxy with three prominent arms wrapping around it, and plenty of extra gas and dark dust between the arms. There are shining blue points throughout the arms and some patches of gas out beyond the galaxy’s edge, where stars are forming. The centre of the galaxy also shines brightly. It is on a dark background where some small orange dots mark distant galaxies.]

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An international team of astronomers has used more than 500 images from the NASA/ESA Hubble Space Telescope spanning two decades to detect seven fast-moving stars in the innermost region of Omega Centauri, the largest and brightest globular cluster in the sky. These stars provide compelling new evidence for the presence of an intermediate-mass black hole. Omega Centauri is visible from Earth with the naked eye and is one of the favourite celestial objects for stargazers in the southern hemisphere. Although the cluster is 17 700 light-years away, lying just above the plane of the Milky Way, it appears almost as large as the full Moon when seen from a dark rural area. The exact classification of Omega Centauri has evolved through time, as our ability to study it has improved. It was first listed in Ptolemy’s catalogue nearly two thousand years ago as a single star. Edmond Halley reported it as a nebula in 1677, and in the 1830s the English astronomer John Herschel was the first to recognise it as a globular cluster. Omega Centauri consists of roughly 10 million stars that are gravitationally bound. [Image Description: A globular cluster, appearing as a highly dense and numerous collection of shining stars. Some appear a bit larger and brighter than others, with the majority of stars appearing blue and orange. They are scattered mostly uniformly, but in the centre they crowd together more and more densely, and merge into a stronger glow at the cluster’s core.]

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Webb takes false-color infrared image of bi-polar protostar nebula

Hourglass nebula as seen in infrared by Webb
Click for original image.

Scientists using the Webb Space Telescope have now produced a new false-color infrared image of the bi-polar hour-glass-shaped protostar nebula dubbed L1527.

That image is to the left, created from data from Webb’s MIRI (Mid-Infrared Instrument) and cropped, reduced, and sharpened to post here. While it is not quite a pretty as a prevous Webb infrared image taken in 2022 by its NIRCam (Near-Infrared Camera), it provides new information about the make-up of materials within this nebula. From the caption:

The areas colored here in blue, which encompass most of the hourglass, show mostly carbonaceous molecules known as polycyclic aromatic hydrocarbons. The protostar itself and the dense blanket of dust and a mixture of gases that surround it are represented in red. (The sparkler-like red extensions are an artifact of the telescopes’s optics). In between, MIRI reveals a white region directly above and below the protostar, which doesn’t show as strongly in the NIRCam view. This region is a mixture of hydrocarbons, ionized neon, and thick dust, which shows that the protostar propels this matter quite far away from it as it messily consumes material from its disk.

Previous to Webb, this object had mostly been studied in 2012 using radio and submillimeter wavelengths (see the papers here and here), but those papers determined this is possibly the youngest known protostar, less than 100,000 years old.

Webb produces false color infrared image of the Crab Nebula

The Crab Nebula as in infrared by Webb
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The false-color infrared picture to the right, reduced and sharpened to post here, was taken by the Webb Space Telescope of the Crab Nebula, located 6,500 light years away and created when a star went supernova in 1054 AD, in order to better understand its make-up and origins. From the caption:

The supernova remnant is comprised of several different components, including doubly ionized sulfur (represented in green), warm dust (magenta), and synchrotron emission (blue). Yellow-white mottled filaments within the Crab’s interior represent areas where dust and doubly ionized sulfur coincide.

The spectroscopic data from this infrared observation has in fact increased the puzzle of the Crab’s origin. Previously the data suggested the supernova that caused it was one type of supernova. This data now suggests it could have been a different type, without precluding the possibility of the first.

“Now the Webb data widen the possible interpretations,” said Tea Temim, lead author of the study at Princeton University in New Jersey. “The composition of the gas no longer requires an electron-capture explosion, but could also be explained by a weak iron core-collapse supernova.”

You can read the published science paper here [pdf].

June 3, 2024 Quick space links

Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.

 

 

 

 

Webb takes an infrared look at the mane of the Horsehead Nebula

Context images
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The mane of the Horsehead Nebula, seen in infrared
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The cool infrared image to the right, cropped, reduced, and sharpened to post here, was taken by the Webb Space Telescope and released today. The three pictures above provide the context, with the rectangle inside the rightmost image indicated the area covered by the close-up to the right.

Webb’s new images show part of the sky in the constellation Orion (The Hunter), in the western side of a dense region known as the Orion B molecular cloud. Rising from turbulent waves of dust and gas is the Horsehead Nebula, otherwise known as Barnard 33, which resides roughly 1,300 light-years away.

The nebula formed from a collapsing interstellar cloud of material, and glows because it is illuminated by a nearby hot star. The gas clouds surrounding the Horsehead have already dissipated, but the jutting pillar is made of thick clumps of material and therefore is harder to erode. Astronomers estimate that the Horsehead has about five million years left before it too disintegrates. Webb’s new view focuses on the illuminated edge of the top of the nebula’s distinctive dust and gas structure.

In the close-up, note the many distant tiny galaxies, both above the mane as well as glowing throught it.

Movies of two supernovae remnants produced from two decades of Chandra X-ray images

Using more than two decades of data from the Chandra X-ray Observatory, scientists have created two movies of the supernovae remnants the Crab nebula and Cassiopeia A.

I have embedded those movies below. From the press release:

Over 22 years, Chandra has taken many observations of the Crab Nebula. With this long runtime, astronomers see clear changes in both the ring and the jets in the new movie. Previous Chandra movies showed images taken from much shorter time periods — a 5-month period between 2000 and 2001 and over 7 months between 2010 and 2011 for another. The longer timeframe highlights mesmerizing fluctuations, including whip-like variations in the X-ray jet that are only seen in this much longer movie. A new set of Chandra observations will be conducted later this year to follow changes in the jet since the last Chandra data was obtained in early 2022.

…Cassiopeia A (Cas A for short) is the remains of a supernova that is estimated to have exploded about 340 years ago in Earth’s sky. While other Chandra movies of Cas A have previously been released, including one with data extending from 2000 to 2013, this new movie is substantially longer featuring data from 2000 through to 2019.

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Hubble celebrates 34 years in orbit with a new photo of the Little Dumbbell Nebula

The Little Dumbbell Nebula
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Cool image time! To celebrate the 34th anniversay of its launch in 1990, astronomers have used the Hubble Space Telescope to take a new photo of the Little Dumbbell Nebula (also known as M76), located about 3,400 light years away and one of the most well-known planetary nebulae in the sky.

That picture is to the right, cropped, reduced, and sharpened to post here. From the caption:

M76 is composed of a ring, seen edge-on as the central bar structure, and two lobes on either opening of the ring. Before the star burned out, it ejected the ring of gas and dust. The ring was probably sculpted by the effects of the star that once had a binary companion star. This sloughed off material created a thick disk of dust and gas along the plane of the companion’s orbit. The hypothetical companion star isn’t seen in the Hubble image, and so it could have been later swallowed by the central star. The disk would be forensic evidence for that stellar cannibalism.

The primary star is collapsing to form a white dwarf. It is one of the hottest stellar remnants known at a scorching 250,000 degrees Fahrenheit, 24 times our Sun’s surface temperature. 
The sizzling white dwarf can be seen as a pinpoint in the center of the nebula. A star visible in projection beneath it is not part of the nebula.



Pinched off by the disk, two lobes of hot gas are escaping from the top and bottom of the “belt,” along the star’s rotation axis that is perpendicular to the disk. They are being propelled by the hurricane-like outflow of material from the dying star, tearing across space at two million miles per hour.

Since launch Hubble has made 1.6 million observations of over 53,000 astronomical objects, and continues to be in high demand by astronomers, with only one request in six able to get time on the telescope. Not surprisingly, almost all of Hubble’s biggest discoveries were unexpected. Its future right now rests with its last three working gyroscopes used to orient it precisely. When one more fails, it will go to one-gyro mode, which will limit the precision of that orientation significantly. At that point the sharpness of the telescope’s imagery will sadly decline.

The only comparable orbital optical telescope now planned is China’s Xuntian optical telescope, scheduled for launch next year. It will fly in formation with the Tiangong-3 space station, allowing astronauts to periodically do maintenance missions to it. As I noted many times previously, American astronomers better start learning Chinese, assuming China even allows them access. Nor will these American astronomers have a right to complain, as it was their decision to not build a Hubble replacement, in their 2000, 2010, and 2020 decadal reports.

potw2417areducedsharpened

This Hubble Picture of the Week depicts the spiral galaxy ESO 422-41, which lies about 34 million light-years from Earth in the constellation Columba. The patchy, star-filled structure of the galaxy’s spiral arms and the glow from its dense core are laid out in intricate detail here by Hubble’s Advanced Camera for Surveys. Images of this galaxy have, however, a decades-long history. The name ESO 422-41 comes from its identification in the European Southern Observatory (B) Atlas of the Southern Sky. In the times before automated sky surveys with space observatories such as ESA’s Gaia, many stars, galaxies and nebulae were discovered by means of large photographic surveys. Astronomers used the most advanced large telescopes of the time to produce hundreds of photographs, covering an area of the sky. They later studied the resulting photographs, attempting to catalogue all the new astronomical objects revealed. In the 1970s a new telescope at ESO’s La Silla facility in Chile performed such a survey of the southern sky, which still had not been examined in as much depth as the sky in the north. At the time, the premier technology for recording images was glass plates treated with chemicals. The resulting collection of photographic plates became the ESO (B) Atlas of the Southern Sky. Astronomers at ESO and in Uppsala, Sweden collaborated to study the plates, recording hundreds of galaxies — ESO 422-41 being just one of those — star clusters, and nebulae. Many were new to astronomy. Astronomical sky surveying has since transitioned through digital, computer-aided surveys such as the Sloan Digital Sky Survey and the Legacy Surveys, to surveys made by space telescopes including Gaia and the Wide-Field Infrared Survey Explorer. Even so, photographic sky surveys contributed immensely to astronomical knowledge for decades, and the archives of glass plates serve as an important historical reference for large swathes of the sky. Some are still actively used today, for instance to study variable stars through time. And the objects that these surveys revealed, including ESO 422-41, can now be studied in depth by telescopes such as Hubble.  [Image Description: A spiral galaxy, with a brightly shining core and two large arms. The arms are broad, faint overall and quite patchy, and feature several small bright spots where stars are forming. A few foreground stars with small diffraction spikes can be seen in front of the galaxy.]Links Pan video: ESO 422-41

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April 16, 2024 Quick space links

Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.

 

 

A whirlpool half-hidden by dust

A whirlpool half-hidden by dust
Click for original image.

Cool image time! The picture to the right, reduced and sharpened to post here, was taken by the Hubble Space Telescope and shows us a magnificent spiral galaxy about 100 million light years away that also has very active nucleus at its center as well as many star-forming regions (in blue) in its outer arms.

That we do not see the same blue spiral arms on the right side of the photo is not because they are lacking, but because a very large stream of dust blocks our view.

This dark nebula is part of the Chamaeleon star-forming region, itself located only around 500 light-years from us, in a nearby part of the Milky Way galaxy. The dark clouds in the Chamaeleon region occupy a large area of the southern sky, covering their namesake constellation but also encroaching on nearby constellations, like Apus. The cloud is well-studied for its treasury of young stars, particularly the cloud Cha I, which has been imaged by Hubble and also by the … James Webb Space Telescope.

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