Starry-shores - No Frontiers

Pickering’s Triangle

Helicoprion: What if, like, teeth,

Mesosaurus: Yeah?

Helicoprion: but WHEEL

Mesosaurus: No don't -

Helicoprion:

(Image by ДиБгд)

Say hello to globular cluster 47 Tucanae 👋

This glittery spray of ancient stars is about 16,700 light-years away from Earth toward the constellation Tucana. Globular clusters like this one are isolated star cities, home to hundreds of thousands of stars that are held together by their mutual gravity. And like the fast pace of cities, there’s plenty of action in these stellar metropolises. The stars are in constant motion, orbiting around the cluster’s center.

Past observations have shown that the heavyweight stars tend to crowd into the “downtown” core area, while lightweight stars reside in the less populated suburbs. But as heavyweight stars age, they rapidly lose mass, cool down and shut off their nuclear furnaces. After the purge, only the stars’ bright, superhot cores – called white dwarfs – remain. This weight loss program causes the now lighter-weight white dwarfs to be nudged out of the downtown area through gravitational interactions with heftier stars.

Until these Hubble observations, astronomers had never seen the dynamic conveyor belt in action. The Hubble results reveal young white dwarfs amid their leisurely 40-million-year exodus from the bustling center of the cluster.

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Crows Are Capable of Conscious Thought, Scientists Demonstrate For The First Time

The research has been published in Science.

New research into the minds of crows has revealed a jaw-dropping finding: the canny corvids aren’t just clever - they also possess a form of consciousness, able to be consciously aware of the world around them in the present. In other words, they have subjective experiences.

This is called primary, or sensory, consciousness, and it had only previously been demonstrated in primates - which means we now may have to rethink our understanding of how consciousness arises, in addition to reconsidering the avian brain.

“The results of our study opens up a new way of looking at the evolution of awareness and its neurobiological constraints,” said animal physiologist Andreas Nieder of the University of Tübingen.

Continue Reading.

Hubble’s Messier Catalog by NASA’s Marshall Space Flight Center

The Himalayan plateau, as seen from the ISS by europeanspaceagency

In honor of the first frost of the year, I propose a new winter cryptid: the Snow Crow.

Who sparks those ice crystals along rooftops and cars?  If they’re in a good spot for sledding, it might just be a Snow Crow.

What are brown dwarfs?

In order to understand what is a brown dwarf, we need to understand the difference between a star and a planet. It is not easy to tell a star from a planet when you look up at the night sky with your eyes. However, the two kinds of objects look very different to an astronomer using a telescope or spectroscope. Planets shine by reflected light; stars shine by producing their own light. So what makes some objects shine by themselves and other objects only reflect the light of some other body? That is the important difference to understand – and it will allow us to understand brown dwarfs as well.

As a star forms from a cloud of contracting gas, the temperature in its center becomes so large that hydrogen begins to fuse into helium – releasing an enormous amount of energy which causes the star to begin shining under its own power. A planet forms from small particles of dust left over from the formation of a star. These particles collide and stick together. There is never enough temperature to cause particles to fuse and release energy. In other words, a planet is not hot enough or heavy enough to produce its own light.

Brown dwarfs are objects which have a size between that of a giant planet like Jupiter and that of a small star. In fact, most astronomers would classify any object with between 13 times the mass of Jupiter and 75 times the mass of Jupiter to be a brown dwarf. Given that range of masses, the object would not have been able to sustain the fusion of hydrogen like a regular star; thus, many scientists have dubbed brown dwarfs as “failed stars”.

A Trio of Brown Dwarfs

This artist’s conception illustrates what brown dwarfs of different types might look like to a hypothetical interstellar traveler who has flown a spaceship to each one. Brown dwarfs are like stars, but they aren’t massive enough to fuse atoms steadily and shine with starlight – as our sun does so well.

On the left is an L dwarf, in the middle is a T dwarf, and on the right is a Y dwarf. The objects are progressively cooler in atmospheric temperatures as you move from left to right. Y dwarfs are the newest and coldest class of brown dwarfs and were discovered by NASA’s Wide-field Infrared Survey Explorer, or WISE. WISE was able to detect these Y dwarfs for the first time because it surveyed the entire sky deeply at the infrared wavelengths at which these bodies emit most of their light. The L dwarf is seen as a dim red orb to the eye. The T dwarf is even fainter and appears with a darker reddish, or magenta, hue. The Y dwarf is dimmer still. Because astronomers have not yet detected Y dwarfs at the visible wavelengths we see with our eyes, the choice of a purple hue is done mainly for artistic reasons. The Y dwarf is also illustrated as reflecting a faint amount of visible starlight from interstellar space.

In this rendering, the traveler’s spaceship is the same distance from each object. This illustrates an unusual property of brown dwarfs – that they all have the same dimensions, roughly the size of the planet Jupiter, regardless of their mass. This mass disparity can be as large as fifteen times or more when comparing an L to a Y dwarf, despite the fact that both objects have the same radius. The three brown dwarfs also have very different atmospheric temperatures. A typical L dwarf has a temperature of 2,600 degrees Fahrenheit (1,400 degrees Celsius). A typical T dwarf has a temperature of 1,700 degrees Fahrenheit (900 degrees Celsius). The coldest Y dwarf so far identified by WISE has a temperature of less than about 80 degrees Fahrenheit (25 degrees Celsius).

Sources: starchild.gsfc.nasa.gov & nasa.gov 

 image credit: NASA / JPL-Caltech

from Asimov’s ‘Nightfall’

Here’s a great explanation of language usage in sci-fi literature for all those who cannot keep their nit-picking to themselves:

Kalgash is an alien world and it is not our intention to have you think that it is identical to Earth, even though we depict its people as speaking a language that you can understand, and using terms that are familiar to you. Those words should be understood as mere equivalents of alien terms-that is, a conventional set of equivalents of the same sort that a writer of novels uses when he has foreign characters speaking with each other in their own language but nevertheless transcribes their words in the language of the reader. So when the people of Kalgash speak of “miles,” or “hands,” or “cars,” or “computers,” they mean their own units of distance, their own grasping-organs, their own ground-transportation devices, their own information-processing machines, etc. The computers used on Kalgash are not necessarily compatible with the ones used in New York or London or Stockholm, and the “mile” that we use in this book is not necessarily the American unit of 5,280 feet. But it seemed simpler and more desirable to use these familiar terms in describing events on this wholly alien world than it would have been to invent a long series of wholly Kalgashian terms.

In other words, we could have told you that one of our characters paused to strap on his quonglishes before setting out on a walk of seven vorks along the main gleebish of his native znoob, and everything might have seemed ever so much more thoroughly alien. But it would also have been ever so much more difficult to make sense out of what we were saying, and that did not seem useful. The essence of this story doesn’t lie in the quantity of bizarre terms we might have invented; it lies, rather, in the reaction of a group of people somewhat like ourselves, living on a world that is somewhat like ours in all but one highly significant detail, as they react to a challenging situation that is completely different from anything the people of Earth have ever had to deal with. Under the circumstances, it seemed to us better to tell you that someone put on his hiking boots before setting out on a seven-mile walk than to clutter the book with quonglishes, vorks, and gleebishes.

If you prefer, you can imagine that the text reads “vorks” wherever it says “miles,” “gliizbiiz” wherever it says “hours,” and “sleshtraps” where it says “eyes.” Or you can make up your own terms. Vorks or miles, it will make no difference when the Stars come out.

-I.A.

-R.S.