Science

Leading economist Kaushik Basu's new book argues that we can increase our overall happiness by thinking more clearly

A rare family murder adds piquancy to Brian Klaas's account of "chance, chaos and why everything we do matters"

Within almost every galaxy there is a supermassive black hole. This by itself implies some kind of formative connection between the two. We have also observed how gas and dust within a galaxy can drive the growth of galactic black holes, and how the dynamics of black holes can both drive star formation or hinder it depending on how active a black hole is. But one area where astronomers still have little information is how galaxies and their black holes interacted in the early Universe. Did black holes drive the formation of galaxies, or did early galaxies fuel the growth of black holes? A recent study suggests the two evolved hand in hand.

It’s difficult to observe the complex dynamics of black holes and galaxies in the early cosmos, but one way to study them is to compare the mass of a galactic black hole with the mass of all the stars in its galaxy. This can be expressed as a ratio MBH / M* to see how it varies over time. This means measuring this ratio at ever-increasing redshifts, since the greater the redshift, the younger the galaxy.

For this study, the team looked at 61 galaxies with active galactic nuclei (AGNs) as identified by X-ray observations. The luminosity of the AGNs gives us an idea of the black hole’s mass. They then added JWST observations of these galaxies from the COSMOS-Web and PRIMER surveys. From these, they could get the infrared luminosity of the galaxies, which let them determine their total stellar mass.

The mass ratios of this study (red dots) compared to earlier studies. Credit: Tanaka, et al

The galaxies they observed have redshifts between z = 0.7 and z = 2.5, meaning that the galaxies are seen as they were 6 billion to 11 billion years ago. What they found is that galaxies and their black holes grow hand in hand. As the galaxy increases in mass, so does the black hole. The relationship is very roughly linear, though the ratio favors the black hole slightly at higher redshifts. For you math geeks, the team found the ratio varies as MBH / M* = (1 + z)0.37. This means the black holes grow at a slightly slower rate than the galaxies.

Unfortunately, the uncertainty of this result is rather large. It will take more observations, particularly at the higher redshift end, to pin down the relation more precisely. But in the coming years, astronomers should be able to gather this data. This study shows that galaxies and their black holes grow at similar rates across billions of years. Future studies will help us understand the more subtle connections between them.

Reference: Tanaka, Takumi S., et al. “The MBH-M* relation up to z = 2 through decomposition of COSMOS-Web NIRCam images.” arXiv preprint arXiv:2401.13742 (2024).

The post Even Early Galaxies Grew Hand-in-Hand With Their Supermassive Black Holes appeared first on Universe Today.

I predicted (or hoped) that with New Zealand’s new Prime Minister, Christopher Luxon of the centrist National Party, New Zealand’s educational system, which was circling the drain, would find its way out. After all, Luxon promised to reform the educational system by emphasizing “teaching the basics.”  (New Zealand performs poorly in math and reading compared to countries of comparable well being.) Most of all, I hoped that Luxon would purge the wokeness of the Kiwi educational system, especially the teaching of indigenous superstitions and “ways of knowing” that seem to be insinuating themselves into science education.

Now I’m not so sure.

Reader Al sent me the tweet below, which was like a (mild) punch in the gut. It comes from the (now protected) account of New Zealand’s Chief Science Advisor, Dame Juliet Gerrard. She was appointed for a three-year term on July 1, 2018, a term that was apparently renewed in 2021 by the woke and now ex-Prime Minister Jacinda Ardern. Gerrard’s present term expires on June 30 of this year. I hope Luxon replaces her, as she’s clearly woke and misguided, and a fan of those who sacralize the indigenous people, a tendency that’s warped New Zealand academics.

At any rate, have a look at this tweet:

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UPDATE:  The tweet appears to be from 2019, but recall that Gerrard is still the Chief Science Advisor for New Zealand. It’s not clear to me when Gerrard locked her account. The point remains that the present Science Adviser to the Prime Minister has a view of sex that is misguided, probably because of wokeness. In my view, she should not be the science advisor, but that may be solved in June.

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The PM of New Zealand's Chief Science Advisor @ChiefSciAdVisor has locked her account after tweeting this stupidity… pic.twitter.com/K0x66eTfnP

— Andy (@lecanardnoir) January 31, 2024

The first sentence is okay, the second is crazy, at least regarding “sex”. The third is mixed, for if you go to Wikipedia under Intersex, you see the declaration that sex is not binary, but also that indicators of sex, like genitalia, are pretty close to binary:

Intersex people are individuals born with any of several sex characteristics including chromosome patterns, gonads, or genitals that, according to the Office of the United Nations High Commissioner for Human Rights, “do not fit typical binary notions of male or female bodies”.

Sex assignment at birth usually aligns with a child’s anatomical sex and phenotype. The number of births with ambiguous genitals is in the range of 1:4,500–1:2,000 (0.02%–0.05%).[3] Other conditions involve atypical chromosomes, gonads, or hormones.

The best source I know of for the frequency of intersex is that of Leonard Sax, which is also quoted ion the Wikipedia article:

A study published by Leonard Sax reports that this figure includes conditions such as late onset congenital adrenal hyperplasia and XXY/Klinefelter syndrome which most clinicians do not recognize as intersex; Sax states, “if the term intersex is to retain any meaning, the term should be restricted to those conditions in which chromosomal sex is inconsistent with phenotypic sex, or in which the phenotype is not classifiable as either male or female,” stating the prevalence of intersex is about 0.018%. This means that for every 5,500 babies born, one either has sex chromosomes that do not match their appearance, or the appearance is so ambiguous that it is not clear whether the baby is male or female.

In both cases, the number of people considered “intersex” is very low.  But that’s pretty much irrelevant to the discussion of whether sex is a spectrum, for biologists, as we discussed yesterday, use a definition of sex involving gametes: if you have the reproductive apparatus to produce small mobile gametes (even if that apparatus is inactive), you’re a male who makes sperm. If you have the apparatus to produce large immobile gametes (even if you can’t, as if you’re postmenopausal or sterile), you’re a female who makes eggs.  If you don’t fit either of these classes, you’re often (but not invariably) classified as intersex.  The athlete Caster Semenya, for example, has internal undescended testes, designed for making sperm, but other female sex traits, like a vagina.  Biologically I’d call her a male, but wouldn’t quarrel if others want to call her “intersex”.

But the point is that intersex individuals are not members of a third sex, so don’t really affect the sex binary: there remain only two types of gametes. We have males, females, and those unclassifiable, with the latter having frequency of one individual in 5600.

I keep repeating myself on the sex binary, along with others like Richard Dawkins, Carole Hooven, and Colin Wright, but I’ll add that the sex binary humans says nothing about the humanity of intersex individuals or transgender individuals (who usually can be classified as biological sex). With a few exceptions involving things like sports and jails, the legal and moral rights of transgender or intersex individuals are independent how “sex” is defined by biologists, and these individuals should never be denigrated for their desire to transition or for the fact that they have a biological condition that makes them intersex.

Finally, the Science Advisor cites Siouxie Wiles, who you can read about on this site (two posts here), a science communicator and microbiologist who’s done some good things, but also vigorously opposed the Listener letter that argued against teaching indigenous ways of knowing as science.  As for @whaeapower on X, it’s another protected account, so I don’t know what it’s about. It may be a Māori site given that “whae” means “mother or aunt” in that language, and because Dame Gerrard has a Māori koru (fern front) tattoo on her back.

At any rate, I guess Dame Gerrard did protect her tweets, as this is what you find when you look for them:

My point, however, is this: the official Science Advisor to the Prime Minister should not be making erroneous statements about sex, even if those statements are made to give succor to people that are not of conventional gender. That she misunderstands sex does not bode well for science education in New Zealand if Dame Gerrard continues in her position after June 30.

As for whether what looks like a quasi-official “X” account should be protected, well, you can be the judge.

Long-lasting hats, jumpers and watch straps that function as smart devices can be made thanks to a cheap and reliable method of creating conductive fibre that can be woven into fabric

Four-atom molecules glued together by microwaves have broken the record for being the most complicated molecule to reach temperatures just billionths of a degree away from absolute zero

DNA from bones found in a cave in Germany has been identified as from Homo sapiens, showing that our species endured frigid conditions there as they expanded across the continent

Prospectors around the world are scrambling to find reserves of "gold hydrogen", a naturally occurring fuel that burns without producing carbon dioxide. But how much is really out there and how easy is it to tap into?

Officials set up almost 2000 camera traps covering 120,000 square kilometres to estimate the number of snow leopards in India’s mountainous regions

My favorite Hindu god, the beloved elephant-headed Ganesha (I have a big collection of bronze Ganesha statues acquired during my many trips to India) appears in today’s Jesus and Mo strip, called “hose.” Remember that in last week’s strip Ganesh appeared as an example of religious discrimination via the Hindu caste system.

Now a Hindu god walks into a bar and. . . . .

The supplement industry continues to be plagued by deliberate adulteration of products.

The post Adulteration of Herbal Supplements Continues first appeared on Science-Based Medicine.

Scientists have mapped the brain circuit behind a form of Alice in Wonderland syndrome, when someone sees themselves or others in distorted proportions, in research that could improve how it is treated

Scientists have analysed the stars that an upcoming NASA telescope will target in its search for biosignatures, narrowing down the candidates for those that could host potential extraterrestrial life

Universe Today has proudly examined the importance of studying impact craters, planetary surfaces, and exoplanets, and what they can teach scientists and the public about finding life beyond Earth. Impact craters both shape these planetary surfaces and hold the power to create or destroy life, and we learned how exoplanets are changing our views of planetary formation and evolution, including how and where we might find life in the cosmos. Here, we will discuss how these disciplines contribute to the field responsible for finding life beyond Earth, known as astrobiology. We will discuss why scientists study astrobiology, also known as astrobiologists, challenges of studying astrobiology, and how students can pursue studying astrobiology, as well. So, why is it so important to study astrobiology?

Dr. Manasvi Lingam, who is an astrobiologist and assistant professor in the Department of Aerospace, Physics and Space Sciences at the Florida Institute of Technology, tells Universe Today, “Astrobiology deals with some of the deepest questions that have fascinated humankind for millennia: Where did we come from? Are we alone? Where are we going?”

The unofficial definition of astrobiology is “the study of life in the universe”. While this is often interpreted as life beyond Earth, it actually includes Earth. Previously, we learned how planetary geologists use Earth as an analog for studying planetary surfaces on other worlds, and astrobiologists also use Earth—which is the only planet known to have life—as an analog for trying to find life on other worlds, as well. They examine the myriad of processes that take place for life to both exist, survive, and thrive on our small, blue world, and ask whether these same processes could be responsible for life existing on other worlds, not just in our solar system, but throughout the universe. Therefore, what are some of the challenges of studying astrobiology?

“Astrobiology is an inherently multidisciplinary and transdisciplinary subject,” Dr. Lingam tells Universe Today. “Hence, it requires acquiring a considerable base of knowledge, and then synthesizing that knowledge in a meaningful fashion.”

What makes the field of astrobiology unique is that it involves a myriad of scientific disciplines and backgrounds. These disciplines include astronomy, astrophysics, biology, chemistry, computer science, geology, physics, and planetary science, who use fieldwork, laboratory studies, and computer models and come together with the common goal of both better understanding life on Earth and how we can find it beyond Earth, as well. A specific aspect of astrobiology that has taken root in the last few years is the study of extremophiles, which is life that can both survive and thrive in environments too extreme for both humans and most of life on the Earth. These extremophiles have been found to live in extreme heat, cold, salinity (salt), and pressure environments. But what has been the most exciting aspect of astrobiology that Dr. Lingam has studied throughout his career?

“I have enjoyed all areas of astrobiology that I have worked on,” Dr. Lingam tells Universe Today. “Some recent highlights include: (1) understanding how information sensing and transmission in varied environments may have shaped the origin and evolution of life; (2) formulating novel detectable signatures of extraterrestrial technology and intelligence (i.e., technosignatures); (3) investigating how high-energy astrophysical processes (e.g., supernovae) can sterilize large portions of galaxies; (4) modeling the lifetimes of technospheres on habitable worlds.”

2017 video showing Dr. Manasvi Lingam discussing how we can detect biosignatures on exoplanets.

While present technological constraints currently limit our direct search for life beyond Earth to our solar system, there are several planetary bodies that are targets for astrobiologists, including the planets Venus and Mars, along with Jupiter’s icy moon, Europa, and Saturn’s largest moon, Titan. Beyond the solar system, the study of exoplanets continues to shape our understanding of the formation and evolution of planets and their atmospheres, some of which exhibit characteristics that vary greatly from what we see in our solar system.

Regarding what advice Dr. Lingam can offer upcoming students who wish to pursue studying astrobiology, he tells Universe Today, “I would advise students to specialize in one particular area (physics in my case) — as it will be the core field through which they interface with astrobiology — while also acquiring a broad knowledge base in fields like chemistry, astronomy, biology, geology, and planetary science.”

Several academic institutions in the United States offer both undergraduate and graduate programs for astrobiology, including Arizona State University, Florida Institute of Technology, Penn State University, and University of Washington. However, it might be safe to assume that any scientific degree of choice could lead to a career in astrobiology, which includes research, academia, and science communication.

Dr. Lingam concludes by telling Universe Today, “Carl Sagan wrote of astronomy: ‘It has been said that astronomy is a humbling and character-building experience.’ This beautiful statement is even more applicable to astrobiology, which grapples with the grand theme of understanding and making sense of our place in the grand cosmic scheme of things.”

How will astrobiology help us better understand our place in the universe in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Astrobiology: Why study it? How to study it? What are the challenges? appeared first on Universe Today.

To find poison ivy before it finds you, scientists have published a new study in which they show how they used artificial intelligence to confirm that an app can identify poison ivy. The app is not yet commercially available, nor is there a timetable for it to be available.

In several billion years, our Sun will become a white dwarf. What will happen to Jupiter and Saturn when the Sun transitions to become a stellar remnant? Life could go on, though the giant planets will likely drift further away from the Sun.

Stars end their lives in different ways. Some meet their end as supernovae, cataclysmic explosions that destroy any orbiting planets and even sterilize planets light-years away. But only massive stars explode like that.

Our Sun is not massive enough to explode as a supernova. Instead, it’ll spend time as a red giant. The red giant phase occurs when a star runs out of hydrogen to feed fusion. It’s a complicated process that astronomers are still working hard to understand. But red giants shed layers of material into space that light up as planetary nebulae. Eventually, the red giant is no more, and only a tiny, yet extraordinarily dense, white dwarf resides in the middle of all the expelled material.

Researchers think that some white dwarfs have debris disks around them, out of which a new generation of planets can form. But researchers have also wondered if some planets can survive as stars transition from the main sequence to red giant to white dwarf.

Researchers at the Space Telescope Science Institute, Goddard Space Flight Center, and other institutions have found what seem to be two giant planets orbiting two white dwarfs in two different systems. Their research is titled “JWST Directly Images Giant Planet Candidates Around Two Metal-Polluted White Dwarf Stars,” and it’s in pre-print right now. The lead author is Susan Mullally, Deputy Project Scientist for JWST.

Theoretical thinking shows that exoplanets should exist around white dwarfs. Outer planets beyond where the asteroid belt is in our Solar System should survive their star’s transition from the main sequence to a red giant to a white dwarf. But stars inside this limit will be engulfed by the red giant as it expands. In our Solar System, the Sun will likely completely engulf or tidally disrupt and destroy Mercury, Venus, and Earth. Maybe even Mars.

Artist’s impression of a red giant star. As these stars lose mass, they expand and can envelop planets that are too close. Credit: NASA/ Walt Feimer

Planets that survive this will likely drift further from the star since the star loses mass and its gravity weakens during the red giant phase.

But the problem is that it’s difficult to detect planets around white dwarfs. Despite pointed efforts, astronomers have only found a few planetary-mass objects orbiting white dwarfs.

As it stands now, Mullally and her colleagues have found two candidate planets around white dwarfs. They’re about 11.5 and 34.5 AU from their stars, which are 5.3 billion and 1.6 billion years old. If the planets are as old as the stars, then MIRI photometry shows that the planets are between 1 to 7 Jupiter masses. They could be false positives, but there’s only a 1 in 3,000 chance that that’s the case.

“If confirmed, these would be the first directly imaged planets that are similar in both age and separation
to the giant planets in our own solar system, and they would demonstrate that widely separated giant
planets like Jupiter survive stellar evolution,” the authors write.

If the researchers are correct, and the planets formed at the same time as the stars, this is an important leap in our understanding of exoplanets and the stars they orbit. It may also have implications for life on any moons that might be orbiting these planets.

But this discovery relates to another issue with white dwarfs: white dwarf metallicity.

Some white dwarfs appear to be polluted with metals, elements heavier than hydrogen and helium. Astronomers think that these metals come from asteroids in the asteroid belt, perturbed and sent into the white dwarf by giant planets. “Confirmation of these two planet candidates with future MIRI imaging would provide evidence that directly links giant planets to metal pollution in white dwarf stars,” the authors write.

Astronomers have found that up to 50% of isolated white dwarfs with hydrogen atmospheres have metals in their photospheres, the stars’ surface layer. These white dwarfs must be actively accreting metals from their surroundings. The favoured source for these metals is asteroids and comets.

“In this scenario, planets that survive the red-giant phase occasionally perturb the orbits of asteroids and comets, which then fall in towards the WD,” the authors write.

This artist’s illustration shows rocky debris being drawn toward a white dwarf. Astronomers think that giant planets perturb smaller objects like asteroids and comets inside the WD’s Roche limit. They’re destroyed, and the debris is drawn onto the star’s surface. Image Credit: NASA, ESA, Joseph Olmsted (STScI)

Astronomers have struggled to find planets around WDs. The main methods of finding planets aren’t very effective around white dwarfs. The transit method used by Kepler and TESS is ineffective because WDs are so tiny and dim. The other method is the radial velocity method. It senses how a star wobbles due to a planet’s influence. It measures the change in the star’s spectrum due to the wobbling. However, WDs have nearly featureless spectra, making radial changes difficult to detect.

But now we have the JWST.

“JWST’s infrared capabilities offer a unique opportunity to directly image Jupiter-mass planets orbiting
nearby WDs,” the researchers write in their paper.

The JWST is powerful enough to directly image large planets around tiny stars without using a coronagraph, as long as the planets are far enough away from the star. “Taking advantage of JWST’s superb resolution, it is possible to directly image a planet at only a few au from nearby WDs without the use of a coronagraph,” Mullally and her colleagues explain.

Part of the effort in this work is identifying point sources. In astronomy, a point source is a single, identifiable source of light. Its opposite is a resolved source or an extended source. The researchers had to be confident that what they’re seeing around the white dwarfs are point sources, which are mostly likely planets in this case. “We expect these to appear as point sources that increase in brightness at longer wavelengths,” they write.

To determine if what they’re seeing are point sources, astronomers use a process called reference differential imaging. It’s a complex procedure, but basically, it involves subtracting the sources from the images. It’s especially effective at finding planets close to stars.

This figure from the research explains some of the findings. Each row is a separate white dwarf and planet candidate. In the top row, the large object in the north is a background galaxy unrelated to the research. The researchers went through a process of subtracting and then adding back in both the stars and the giant planet candidates. Image Credit: Mullally et al. 2024.

The figure above shows how the team worked with the images, subtracting both the white dwarf and the candidate planets and identifying the planets as point sources. “In both cases, the candidate is removed cleanly, indicating it is point-source in nature,” the authors write. The researchers examined four separate white dwarfs and only two of them have candidate exoplanets.

“If confirmed, these two planet candidates provide concrete observational evidence that outer giant planets like Jupiter survive the evolution of low-mass stars,” the authors write. Confirmation would also support the idea that 25%-50% of white dwarfs host large planets. That’s a big step forward in understanding.

But these results unfortunately can’t answer another question: are large planets responsible for sending debris onto the surface of white dwarfs? “The confirmation of these planets are not, however, sufficient to fully validate that large-mass giant planets are the driver of accretion without further observations,” writes Mullally and her co-authors.

An answer to that question can only come from observing more white dwarfs, especially with the JWST. Hopefully, we won’t have to wait long.

The post Webb Directly Images Two Planets Orbiting White Dwarfs appeared first on Universe Today.

Not only can parrots fly and walk, they can also swing along branches using their beak, in a technique called beakiation

An international team has developed a new method to make and manipulate a widely studied class of high-temperature superconductors. This technique should pave the way for the creation of unusual forms of superconductivity in previously unattainable materials.

An international team has developed a new method to make and manipulate a widely studied class of high-temperature superconductors. This technique should pave the way for the creation of unusual forms of superconductivity in previously unattainable materials.

NGC 4753 is a prime example of what happens after a galactic merger. It looks like a twisted mess, with dust lanes looping around the massive galactic nucleus. Astronomers long wondered what happened to this galaxy, and with a sharp new image created by the Gemini South telescope, they can finally explain its tortured past.

Officially, NGC 4753 is classified as a “peculiar” galaxy due to its odd appearance. But, like other survivors of galactic mergers and acquisitions, it has probably had several “shapes” throughout its history. Most galaxies are classified as spirals, ellipticals, lenticulars, and irregulars. For this one, astronomers suspect it was formerly a lenticular with a substantial disk and not much in the way of spiral arms. Then, more than a billion years ago, it encountered a neighboring dwarf galaxy and they tangled together. A team led by astronomer Tom Steiman-Cameron at Indian University studied this galaxy in great detail to understand how it got the way it is today. “Galaxies that gobble up another galaxy often look like train wrecks,” he said, ”and this is a train-wreck galaxy.”

NGC 4753 lies in the Virgo Cluster of galaxies, at a distance of about 60 million light-years. It lies within its own smaller galactic collective, called the NGC 4753 group. The galaxy itself appears to have a dark matter shell, and about a thousand globular clusters orbiting its core. Its peculiar dust lanes first caught astronomers’ attention in the 20th Century, although the galaxy itself was discovered by William Herschel in 1784.

Galactic Mergers and Acquisitions

Galaxies have merged throughout the history of the Universe. In the beginning, small shreds of galaxies mixed with their neighbors to form larger ones. That process continued, creating the amazing diversity of galactic forms we see today. When galaxies meet like this, they mingle their stars and material. Gravitational forces sculpt the galaxies, and shock waves induce waves of star birth. This makes galaxies very dynamic objects, changing over time as they meet and mingle with their neighbors.

An HST image of the interacting galaxies in IC 1623. They are plunging headlong into one another in a process known as a galactic merger. That ignited a frenzied spate of star formation known as a starburst, creating new stars at a rate more than twenty times that of the Milky Way galaxy.

We see this process playing out across the Universe. Our own Milky Way Galaxy is the result of numerous galactic mergers since it began to form about 13 billion years ago. Each collision brought infusions of new stars and interstellar gas and dust and changed our galaxy’s appearance. Today, the Milky Way is a barred spiral shape, but it began as an indistinct lump of stars, gas, and dust in the early Universe. It continues its merger history in modern times. Astronomers are tracking the action as our galaxy gobbles up several smaller galaxies, including the Sagittarius Dwarf. In addition, the Milky Way and Andromeda galaxies will merge in about five billion years. That process will radically alter their shapes, too, resulting in a vast galaxy known as Milkdromeda.

View of Milkdromeda from Earth “shortly” after the galactic merger of the Milky Way and Andromeda, around 3.85-3.9 billion years from now Credit: NASA, ESA, Z. Levay and R. van der Marel (STScI), T. Hallas, and A. Mellinger A Tale of NGC 4753’s Galactic Merger

When NGC 4753 began its cosmic dance, it tangoed with a gas-rich dwarf galaxy. Bursts of star formation triggered by the collision (and influx of gas) injected huge amounts of dust into the region. The galaxy followed a spiraling path into the collision, and that smeared out the dust into the disk. Ultimately, the activity gave the galaxy its peculiar look. “For a long time nobody knew what to make of this peculiar galaxy,” said Steiman-Cameron. “But by starting with the idea of accreted material smeared out into a disk, and then analyzing the three-dimensional geometry, the mystery was solved. It’s now incredibly exciting to see this highly-detailed image by Gemini South 30 years later.”

Steiman-Cameron and his team explain the galaxy’s peculiarity with a phenomenon known as “differential precession”. Precession occurs when a rotating object’s axis of rotation changes orientation, like a spinning top. Differential means that the rate of precession varies depending on the radius. For the dusty accretion disk orbiting the galactic nucleus in this collision, the rate of precession is faster toward the center and slower near the edges. This galactic wobble-like motion results from the angle at which NGC 4753 and its former dwarf companion collided. That resulted in the strongly twisted dust lanes threading through this galaxy.

Implications for Other Peculiar Galaxies

Interestingly, although this galaxy certainly looks weird enough in the Gemini image, it’s all a matter of viewing perspective. We’re looking at it from an edge-on view. That’s how we can spot the dust lanes and other features in the disk.

A model of NGC 4753 as seen from various viewing orientations. From left to right and top to bottom, the angle of the line of sight to the galaxy’s equatorial plane ranges from 10° to 90° in steps of 10°. Although galaxies similar to NGC 4753 may not be rare, only certain viewing orientations allow for easy identification of a highly twisted disk. This infographic is a recreation of Figure 7 from a 1992 research paper.

But, if we could get in a spaceship and fly directly “north” of NGC 4753 to get a “top-down” view, it would look pretty much like a standard spiral galaxy. Now that astronomers know about its galactic merger history, they can do further studies to understand its stellar populations and interactions of those bizarre dust lanes. And, its history may go a long way toward explaining the appearances of other “peculiar” galaxies in the Universe.

For More Information

Gemini South Captures Twisted Dusty Disk of NGC 4753, Showcasing the Aftermath of Past Merger
The Remarkable Twisted Disk of NGC 4753 and the Shapes of Galactic Halos

The post The Aftermath of a Recent Galactic Merger appeared first on Universe Today.