Tag: science

Hubble eyes the Egg Nebula

10:48 am

Hubble eyes the Egg Nebula
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Cool image time! The picture to the right, reduced to post here, was taken by the Hubble Space Telescope as part of a study of “preplanetary nebula,” the initial stages of a planetary nebula that forms as some star types begin dying. From the caption:

Many preplanetary nebulae are relatively dim and hard to spot. They are made of layers of gas ejected by the star, but that star is not yet hot enough to ionise the gas and cause it to glow. The Egg Nebula is relatively unique, easily visible as a sparkling jewelled egg in space. Powerful beams of starlight blast out of the inner cloud, two a-side, giving a breathtaking illumination to this cosmic structure. Fast-moving outflows of hot molecular hydrogen also emerge from within the dust cloud, visible just at the base of the searchlight beams. These outflows glow with infrared light, which is shown in this image by orange highlights.

The central cloud of dust is surrounded by concentric rings, themselves made up from thin, faint arcs of gas. These were created by successive outbursts from the central star, which ejected a little more material from its outer surface every few hundred years. The beams of starlight are reflected by these layers of gas, creating an appearance like ripples on the surface of water. The way that gas molecules reflect and scatter light gives a bluish colour to the arcs. The reflected starlight reveals important details about the central star, which is impossible to view directly in its dusty shell.

Many planetary nebula get their spectacular shapes because they have a binary star system in their center, that act like the blades in a blender as they circle each other, mixing the materials the stars’ eject to form those shapes. Because of those surrounding shells, it is often impossible to determine with the nebula has a single central star, or a binary system.

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How Saturn’s moon Enceladus causes an aurora on Saturn

9:38 am

Enceladus orbiting Saturn
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Using data collected by the orbiter Cassini while it orbited Saturn more than a decade ago, scientists now think they have mapped out how the moon Enceladus interacts with Saturn’s magnetic field and helps create an aurora in Saturn’s polar regions.

You can read the paper here. The artist rendering to the right comes from the press release, and shows that interaction. From that release:

The study, published in the Journal of Geophysical Research: Space Physics, shows how wave structures, known as ‘Alfvén wings’, travel like vibrations on a string along magnetic field lines connecting Enceladus to Saturn’s pole. The initial ‘main’ Alfvén wing is reflected back-and-forth both by Saturn’s ionosphere and the plasma torus that encircles Enceladus’s orbit, resulting complex and structured system. By using a multi-instrumental approach, researchers were able to show that the influence of Enceladus extends over a record distance of over 504,000 km – more than 2,000 times the moon’s radius.

…As well as the large-scale structures, the team found evidence that turbulence teases out the waves into filaments within the main Alfvén wing. This fine-scale structure helps the waves bounce off Enceladus’s plasma torus and reach the high-latitudes in Saturn’s ionosphere where auroral features associated with the moon form.

The white haze below Enceladus in the graphic represents the material that comes out of the “tiger stripe” fractures near its south pole.

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A lava tube on Venus?

9:18 am

Theorized lava tube on Venus

The uncertainty of science: Scientists in Italy have reanalyzed the radar data of Venus by the Magellan orbiter from 1990 to 1992 and concluded that at least one open pit on the side of a shield volcano might be the entrance to a underground lava tube.

You can read their paper here [pdf]. The graphic above comes from figures 2 and 3 of their paper, with the radar image of the pit to the right, and the cartoon to the left their interpretation of that radar data. From the abstract:

Between 1990 and 1992, the Synthetic Aperture Radar (SAR) instrument on board the Magellan spacecraft mapped the Venusian surface. By leveraging a SAR imaging technique developed for detecting and characterizing accessible subsurface conduits in the proximity of skylights, we analysed
the Magellan radar images in locations where there is evidence of localized surface collapses. Our analyses reveal the existence of a large and open subsurface conduit in the Nyx Mons region. This feature is hypothesized to be a pyroduct, characterized by a diameter of about 1 km, a roof thickness of at least 150 m and an empty void height of no less than 375 m. The conduit extends in the subsurface for at least 300 meters from the skylight.

To strengthen their conclusions, which are based on a LOT of assumptions, the scientists also compared this radar data with radar data taken of similar-sized lava tube skylights on Earth.

Their conclusion is reasonable, as Venus is a planet of volcanoes, with more than a million detected in radar data. Lava tubes should exist. Nonetheless, their interpretation of the radar data is very uncertain, and must be viewed with a great deal of skepticism.

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India picks landing site for its Chandrayaan-4 lunar sample return mission

10:22 am

Landing sites at the Moon's South Pole

Scientists at India’s space agency ISRO have now picked [pdf] a preliminary landing site for its planned Chandrayaan-4 lunar sample return mission, scheduled to launch in 2028.

[Four] sites of Mons Mouton area was fully characterised with respect to terrain characteristics using high resolution OHRC multiview image datasets and it was found that 1km x 1km area around MM-4 (-84.289, 32.808) contains the less hazard percentage, mean slope of 5°, Mean height of 5334m and most number of hazard free grids of size 24m x 24m. Hence MM-4 can be considered for the potential site of Chandrayaan-4 mission.

The study area of all four sites is indicated on the map to the right by the red dot labeled “Chandrayaan-4”. This mountain, Mons Mouton, is essentially a flat plateau between the numerous craters in the south pole region (many with permanently shadowed craters). Intuitive Machines second lander, Athena, attempted a landing there last year, and tipped over, as did that company’s first lander, Odysseus, both indicated in green. Astrobotic’s Griffin lander (yellow) is targeting this mountain also, hopefully to launch later this year.

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One of Cassini’s first close-up images of Saturn’s rings

12:48 pm

The rings of Saturn
Click for original image.

Cool image time! My exploration of the Cassini image archive continues. The picture to the right, reduced and enhanced to post here, was taken on May 2, 2005 by Cassini soon after it moved into a close orbit of Saturn where it could get high resolution images of Saturn’s rings. This is one of the first.

This is also a raw image that has not been calibrated or validated, to use the science team’s terms. Thus, the white dots scattered across the image could be artifacts that need to be cleaned up, not examples of Saturn’s many moons.

Regardless, the image illustrates the incredible delicacy of these rings, despite the fact that they are gigantic, spanning almost 45,000 miles in width, with a thickness ranging from 30 to 1,000 feet. And yet, there are so many distinct rings they almost resemble an old-fashioned vinyl record.

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Pluto’s implausible atmosphere, as seen in 2015 by New Horizons

2:07 pm

Pluto's implausible atmosphere
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Cool image time! The picture to the right, cropped to post here, was taken on July 14, 2015 by the camera on the New Horizons probe as it flew past Pluto, the only time a human craft has gotten close to this distant planet. From the link:

These high phase angle images show many artifacts associated with scattered sunlight; the Sun was less then 15 degrees from the center of the LORRI frame for these observations. But the outline of Pluto and its hazy atmosphere are also visible.

To see the atmosphere the light from the planet itself has been blocked out.

What is implausible about Pluto’s atmosphere is the location of the planet, about 3.7 billion miles from the Sun, out in the nether reaches of the solar system. At that distance sunlight is very weak, and produces very little energy. And yet, there is enough energy here to produce an atmosphere of mostly nitrogen gas, with trace amounts of metane and carbon monoxide. Scientists think this atmosphere only exists when Pluto is closer to the Sun in its somewhat oblong orbit, and freezes out the rest of the time. As Pluto was just retreating in 2015 from that closest approach in the last two decades of the 20th century, New Horizons could detect its presence.

But then, we really can’t be sure if this atmosphere truly vanishes when the planet is farthest from the Sun, as we have only so far observed 96 years in Pluto’s 248-year orbit.

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Astronomers use SphereX infrared space telescope to study interstellar Comet 3I/Atlas

8:32 am

False color images of SphereX infrared data
False color images of SphereX infrared data.
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Using NASA’s SphereX infrared space telescope, astronomers have now detected a range of new molecules in the coma surround interstellar Comet 3I/Atlas as that coma brightened and grew in December 2025 following the comet’s closest approach to the Sun in the fall.

You can read the research paper here. From the press release:

In a new research note, mission scientists describe the detection of organic molecules, such as methanol, cyanide, and methane. On Earth, organic molecules are the foundation for biological processes but can be created by non-biological processes as well. The researchers also note a dramatic increase in brightness two months after the icy body had passed its closest distance to the Sun, a phenomenon associated with comets as they vent water, carbon dioxide, and carbon monoxide into space.

In every way this interstellar object continues to behave like an ordinary comet, which is actually quite profound. It tells us the rest of the universe is not that different than our solar system.

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One of Saturn’s many weird moons

11:47 am

Saturn's moon Atlas
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Cool image time! The picture to the right, cropped and reduced to post here, was taken on April 13, 2017 by the orbiter Cassini as it began it last close loops around Saturn before diving into its atmosphere to burn up.

Those close loops allowed it to get good close-up images of a few of the tiny moons that orbit in or close to the gas giant’s rings. On the right is one of those pictures, of the moon Atlas, taken from a distance of about 10,000 miles.

The moon’s weird ravioli shape is thought to be caused by the accretion of dust and ice from the nearby rings along Atlas’s equator.

Scientists also found the moon surfaces to be highly porous, further confirming that they were formed in multiple stages as ring material settled onto denser cores that might be remnants of a larger object that broke apart. The porosity also helps explain their shape: Rather than being spherical, they are blobby and ravioli-like, with material stuck around their equators. “We found these moons are scooping up particles of ice and dust from the rings to form the little skirts around their equators,” Buratti said. “A denser body would be more ball-shaped because gravity would pull the material in.”

Atlas itself is about 25 miles wide and about 11.5 miles thick, at its thickest point. I suspect if you tried to walk on it you would sink into the accumulated dust and ice, as it is likely no more dense as newly fallen snow.

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A nice summary of all space-based research of reproduction in space

10:12 am

Regulatory recommendations by these scientists
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Link here to the press release. The paper itself can be read here.

The paper is an excellent summary of practically all the research that has been done in space and on the ground studying the impact of the harsh environment of space on reproduction. It notes above all that we really know very little despite this research, because the risks to the newborn have precluded direct study. From the paper’s abstract:

Despite over 65 years of human spaceflight activities, little is known of the impact of the space environment on the human reproductive systems during long-duration missions. Extended time in space poses potential hazards to the reproductive function of female and male astronauts, including exposure to cosmic radiation, altered gravity, psychological and physical stress, and disruption to circadian rhythm.

This review encapsulates current understanding of the effects of spaceflight on reproductive physiology, incorporating findings from animal studies, a recent experiment on sperm motility, and omics-based insights from astronaut physiology. Female reproductive systems appear to be especially vulnerable, with implications for oogenesis and embryonic development in microgravity. Male reproductive function reveals compromised DNA integrity, even when motility appears to be preserved. This review examines the limited embryogenesis studies in space, which show frequent abnormal cell division and impaired development in rodents.

In the paper’s conclusion, these academics sadly revert to type, and propose the establishment of an international regulatory framework for controlling this issue, as shown in the graphic to the right. This is empty foolishness, because such regulations will only do more harm than good, stifling research while failing to accomplish anything.

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Pluto and Charon come out of the dark

1:40 pm

Pluto and Charon come out of the dark
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Cool image time! I have decided to start delving into the archives of some of the older planetary missions, because there is value there that is often forgotten now years later, that should not be forgotten.

In looking through the archive of images from the main camera on New Horizons as it sped past Pluto in July 2015, I found the picture to the right, taken on July 10, 2015 when New Horizons was still about three million miles away.

This is the raw image from that camera, cropped, reduced, and sharpened to post here. It is also the first time in human history we had a sharp look at these two planets that sit at the outer fringes of the solar system. The science team that day released a version that they enhanced to bring out the details, which I immediately posted. They then noted the following:

A high-contrast array of bright and dark features covers Pluto’s surface, while on Charon, only a dark polar region interrupts a generally more uniform light gray terrain. The reddish materials that color Pluto are absent on Charon. Pluto has a significant atmosphere; Charon does not. On Pluto, exotic ices like frozen nitrogen, methane, and carbon monoxide have been found, while Charon’s surface is made of frozen water and ammonia compounds. The interior of Pluto is mostly rock, while Charon contains equal measures of rock and water ice. “These two objects have been together for billions of years, in the same orbit, but they are totally different,” said Principal Investigator Alan Stern of the Southwest Research Institute (SwRI), Boulder, Colorado.

This difference is quite clear in the raw image, with Charon markedly dimmer than Pluto even though they are getting the same amount of light from the Sun.

More than any other objects in the solar system, the double planet system of Pluto-Charon demonstrates how uniquely different every object in the solar system is from every other object. Even when formed together, as these two planets were, they formed in a manner that made them drastically different.

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Dumb science: Researchers claim Jupiter is 0.0028% thinner than previously measured

9:29 am

Stupidity on display: According to researchers using data from the Jupiter orbiter Juno, Jupiter is a tiny bit thinner at the equator and flatter at the poles than previously measured.

Leading an international team from Italy, the United States, France and Switzerland, Weizmann Institute of Science researchers [Israel] have produced more precise measurements of Jupiter’s size and shape than ever before, using new data from NASA’s Juno spacecraft.

The peer-reviewed research, published today in Nature Astronomy, shows that the radius of Jupiter is about four kilometers (2.5 miles) thinner at its equator and 12 kilometers (7.5 miles) flatter at the poles than believed in earlier assessments. The scientists determined the planet has a radius of 71,484 kilometers (44,418 miles). Earlier data measured it at 71,492 kilometers (44,423 miles).

The absurdity of this research is galling. The revision they claim is tiny, a mere 0.0028% difference at the equator, and 0.0084% at the poles. These numbers are insignificant. Moreover, Jupiter is a gas giant. It has no precisely known surface. Instead, it has an atmosphere that gradually thins as you go up. To claim any precise diameter is absurd, especially because seasonally and over time that atmosphere will expand and shrink.

And of course, at least two mainstream news outlets, Scientific American and The Times of Israel (linked above), report this story without any skepticism, as if this is a Earth-shaking discovery. All that tells me is that when it comes to science, both are incompetent sources of information.

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A galaxy’s swirling dust lanes

12:07 pm

A galaxy with swirling dust lanes
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Cool image time! The picture to the right, cropped, reduced, and enhanced to post here, was taken by the Hubble Space Telescope as part of follow-up observations of a now faded supernovae that occurred there two years earlier.

This was on purpose: the aim of the observations was to witness the aftereffects of the supernova and examine its surroundings, which can only be done once the intense light of the explosion is gone.

The galaxy itself, NGC 7722, is 187 million light years away, and is unusual in itself.

A “lenticular”, meaning “lens-shaped”, galaxy is a type that sits in between the more familiar spiral galaxies and elliptical galaxies. It is also less common than these — partly because when a galaxy has an ambiguous appearance, it can be hard to determine if it is actually a spiral, actually an elliptical galaxy, or something in between. Many of the known lenticular galaxies sport features of both spiral and elliptical galaxies. In this case, NGC 7722 lacks the defined arms of a spiral galaxy, while it has an extended, glowing halo and a bright bulge in the center similar to an elliptical galaxy. Unlike elliptical galaxies, it has a visible disc — concentric rings swirl around its bright nucleus. Its most prominent feature, however, is undoubtedly the long lanes of dark red dust coiling around the outer disc and halo.

The streak in the lower left is a very distant background galaxy, seen on edge.

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