star forming galaxies

10

Closest Supernova In Years Brings Cosmic Fireworks To Earth’s Skies

“Cosmic fireworks like these don’t truly happen at random; they are clustered in time and space around the most massive, intense star-forming regions of all. You can’t have a bigger star-forming region than one that includes the entire galaxy, and the sweeping, grand, irregular arms of the Fireworks galaxy are as good as they come. Based on what we see, we expect this elevated rate to continue for more than a million years.”

Every once in a while, a new light appears somewhere in the night sky: the result of a massive star reaching the end of its life. From many millions of light years away, the brilliance of a supernova shines across the cosmos. Just a few days ago, a new light was discovered in a galaxy only 22 million light years away, making it the closest supernova discovered in three years. The galaxy housing it is a hotbed of supernova formation, having been home to ten such explosions in the past 100 years: more than we’ve found in any other galaxy. The reason? This entire galaxy, despite having only half the stars of the Milky Way, is a giant star-forming region. Starburst galaxies like this are the best place to look for cataclysmic events like this, and NGC 6946 is maybe the best example of all.

Come see the night sky’s newest, closest supernova, and learn how to see it for yourself!

10

Ask Ethan: What Surprises Might NASA’s Future Space Telescopes Discover?

“One of the primary science goals for WFIRST is to survey the sky out to very large distances to look for new type Ia supernovae. These are the same events that led to the discovery of dark energy, but instead of tens or hundreds, it will collect many thousands, and out to very large distances. And what it will allow us to measure is not just the rate of expansion of the Universe, but how it’s changed over time, to about ten times better precision than we can currently measure. If dark energy is different from a cosmological constant by even 1%, we’ll find it. And if it’s even 1% more negative than a cosmological constant’s negative pressure, our Universe will end in a Big Rip.”

We know what NASA’s James Webb and WFIRST are designed for, and we know what we expect to find. James Webb will be the largest space telescope ever, focused mostly on infrared observations probing exoplanets, star-forming nebulae, galaxy evolution and the first stars and galaxies in the Universe. WFIRST will be just like Hubble, except with better instruments and 100 times the field-of-view. But the best discoveries from Hubble were things like dark energy: things we didn’t expect to find! What might some of the surprises be – without hypothesizing radical new physics – that these two observatories might uncover? They range from signatures of exoplanetary life to being able to possibly falsify dark matter, and they’re all incredible.

Find out seven of the most tantalizing possibilities today, on this week’s astonishing Ask Ethan!

Dawn of the cosmos: Seeing galaxies that appeared soon after the Big Bang

Arizona State University astronomers Sangeeta Malhotra and James Rhoads, working with international teams in Chile and China, have discovered 23 young galaxies, seen as they were 800 million years after the Big Bang. The results from this sample have been recently published in the Astrophysical Journal.

Long ago, about 300,000 years after the beginning of the universe (the Big Bang), the universe was dark. There were no stars or galaxies, and the universe was filled with neutral hydrogen gas. In the next half billion years or so the first galaxies and stars appeared. Their energetic radiation ionized their surroundings, illuminating and transforming the universe.

Keep reading

7

The Future Of Astronomy: Thousands Of Radio Telescopes That Can See Beyond The Stars

“Radio astronomy has brought us pulsars, quasars, microquasars, and mysterious sources like Cygnus X-1, which turned out to be black holes. The entire Universe is out there, waiting for us to discover it. When SKA is completed, it will shed a light on the Universe beyond stars, galaxies, and even gravitational waves. It will show us the invisible Universe as it truly is.”

When we break out the big guns – space telescopes like Hubble or James Webb – we can see the Universe as it was billions of years ago, if we look for long enough. From the first moment that the Universe forms stars and galaxies, so long as that light has a path to our eyes, humanity can view it with the right equipment. This record-breaking approach has brought us in contact with galaxies from as early as when the Universe was just 400 million years old: 3% of its current age. Yet no matter how far back we go, we’ll never be able to see the era from before there were stars or galaxies at all using this approach. But a new, ambitious project just might. The Square Kilometer Array (SKA), set to begin construction next year, will map out the invisible hydrogen in the Universe, including during the epochs in where there are no stars at all.

In the truest sense, these thousands of radio telescopes, working together, will reveal the invisible Universe at long last. Come find out how!

New insight into dark matter halos

Research from the University of Pennsylvania could shed light on the distribution of one of the most mysterious substances in the universe.

In the 1970s, scientists noticed something strange about the motion of galaxies. All the matter at the edge of spiral galaxies was rotating just as fast as material in the inner part of the galaxy. But according to the laws of gravity, objects on the outskirts should be moving slower.

The explanation: A form of matter called dark matter that does not directly interact with light.

Keep reading

The towering primary mirror of NASA’s James Webb Space Telescope stands inside a cleanroom at NASA’s Johnson Space Center in Houston, where it will undergo its last cryogenic test before it is launched into space in 2018. In preparation for testing, the “wings” of the mirror (which consist of the three segments on each side) were spread open.  This photo shows one fully deployed wing, and one that is moments from being fully deployed. An engineer observes the move.

The James Webb Space Telescope is the world’s most advanced space observatory. This engineering marvel is designed to unravel some of the greatest mysteries of the universe, from discovering the first stars and galaxies that formed after the big bang to studying the atmospheres of planets around other stars. It is a joint project of NASA, ESA (the European Space Agency) and the Canadian Space Agency.

Image Credit: NASA/Chris Gunn

James Webb Space Telescope

Time And Space

8

Earliest, Brightest Galaxies Shine A Ghostly Green In Surprising New Find

“But there’s another, green line that happens only when oxygen gets doubly ionized at the hottest temperatures of all: 50,000 K and above. Only planetary nebulae, with super-hot young white dwarfs, and the ultra-rare “green pea” galaxies exhibit these features. But by looking at the most active star-forming galaxies in the Subaru Deep Field (above), Matthew Malkan and Daniel Cohen found, that all galaxies from 11 billion years ago or more emit this green signature.”

Galaxies come in many different colors today: white, blue or red, mostly, depending on the populations of stars inside. But in a very rare set of circumstances, there can be green emissions as well, due mostly to the emission lines of doubly-ionized oxygen. The problem is we only see these in extraordinarily hot regions of the Universe, where ultra-hot stars or extremely unusual ultraviolet processes are found. Yet by looking at the farthest star-forming galaxies available, two scientists broke the light up into components and found something shocking: this green emission feature was found to be incredibly strong in every one of thousands of galaxies that fit the criteria. It leads to a huge mystery: how do these ultra-hot stars form in the first place? Is it metallicity? Higher stellar masses? Or a top-heavy initial mass function?

The jury’s still out, but it’s looking more-and-more like these are the galaxies that reionized the Universe in the first place! Come get the whole story on this week’s Mostly Mute Monday!

Bones made of elements that form stars and galaxies, they say.
But mine must be of sadness and crippling anxiety, to make me feel this way.
—  M.C.E I cannot be made up of the same as you // You are perfect and I am chaos.

This shot from the NASA/ESA Hubble Space Telescope shows a maelstrom of glowing gas and dark dust within one of the Milky Way’s satellite galaxies, the Large Magellanic Cloud (LMC). This stormy scene shows a stellar nursery known as N159, an HII region over 150 light-years across. N159 contains many hot young stars. 

10

The James Webb Space Telescope Will Truly Do What Hubble Only Dreamed Of

“By the same token, the James Webb Space Telescope will teach us an incredible amount about the Universe, including further details about how stars form, what the earliest stellar populations look like, will show us gas giants and rogue planets in unprecedented detail and will tell us what made up the Universe at any given time in the past. It will show us a whole slew of things that Hubble cannot, by virtue of it reaching to much longer wavelengths of light than Hubble could ever hope to see. And with its huge, large-aperture primary mirror, it will be able to collect more light in a single day than Hubble could in a week. The most exciting things, of course, will be the unexpected: the things we’ll discover that we don’t even know to look for yet.

But even if you don’t learn about any of the science that James Webb will bring to us, there’s one thing it will deliver that everyone can enjoy: the James Webb Space Telescope will show us how the Universe grew up.”

The Hubble Space Telescope, for all of its scientific findings and how it revolutionized our understanding of the Universe itself, touched us all in a way that no piece of knowledge could ever encapsulate. In perhaps the greatest find of all, Hubble answered a question that many of us have had on our minds every time we’ve gazed up at a night sky: what does the Universe actually look like? From its images of star-forming regions, stellar deaths, galaxies, gravitational lenses and the deep abyss of empty space, it’s awed us in a way no other observatory ever has. But James Webb is poised to do us one better, and show us something Hubble never could. It will show us how the Universe went from a state with no stars, no planets, and no galaxies to the Universe we know, recognize and inhabit today.

In short, the James Webb Space Telescope will show us how the Universe grew up. Come learn exactly what that means, and see if you aren’t awed by the possibility!

anonymous asked:

Would you say evolution and science are compatible with HP? Just making sure I have the right idea here.

Religion has the reputation of being un-scientific. By its definition, religion—the believe in something one can’t prove—seems the polar opposite of science. So what of Hellenismos? Is that incomaptible with science like most major world religions? No. What I love about Hellenic mythology and philosophy is that it works with science—and the ancient philosophers agreed.

I have explained before how I differentiate between mythology and philosophy, where I feel myth was inspired by the Theoi Themselves, while philosophy was created by humans who saw society and drew conclusions from it. These conclusions often included a religious aspect because society was religious (even though the ancient Hellenes didn’t have a word for ‘religion’), but at its core, they deal not with religious matters. They deal with the influence of religion on humanity and society.

An example: the ancient Hellenic philosophers and mythographers were pretty much in agreement, however, that the Gods, indeed, created the universe—or are the universe itself. The most famous account of how everything came to be comes from Hesiod. His ‘Theogogy’ is a complete recounting of the story, starting with Khaos:

“Verily at the first Chaos came to be, but next wide-bosomed Earth, the ever-sure foundations of all  the deathless ones who hold the peaks of snowy Olympus, and dim Tartarus in the depth of the wide-pathed Earth, and Eros, fairest among the deathless gods, who unnerves the limbs and overcomes the mind and wise counsels of all gods and all men within them. From Chaos came forth Erebus and black Night; but of Night were born Aether and Day, whom she conceived and bare from union in love with Erebus. And Earth first bare starry Heaven, equal to herself, to cover her on every side, and to be an ever-sure abiding-place for the blessed gods. And she brought forth long Hills, graceful haunts of the goddess-Nymphs who dwell amongst the glens of the hills. She bare also the fruitless deep with his raging swell, Pontus, without sweet union of love. But afterwards she lay with Heaven and bare deep-swirling Oceanus, Coeus and Crius and Hyperion and Iapetus, Theia and Rhea, Themis and Mnemosyne and gold-crowned Phoebe and lovely Tethys. After them was born Cronos the wily, youngest and most terrible of her children, and he hated his lusty sire.” [ll. 116-138]
He goes on to list a great many deities, cutting out a rough shape of the cosmos while doing so. There are many variations of this family tree, and in the ancient writings, there are also creation stories that range beyond this basic framework. Many of them match very well with science, though.

I believe in the theory of the Big Bang, where the universe was in an extremely hot and dense state and began expanding rapidly. After the initial expansion, the universe cooled sufficiently to allow energy to be converted into various subatomic particles, including protons, neutrons, and electrons. Giant clouds of these primordial elements later coalesced through gravity to form stars and galaxies, and the heavier elements were synthesized either within stars or during supernovae (courtesy of Wikipedia, because of ease). I see no issue in overlaying this theory with Hesiod’s cosmology, however. The Big Bang theory does sound like first there was Khaos, and from that, matter came into being to eventually form the Earth as it is now. So as far as the creation of the universe and the Gods goes, I will go with Hesiod and his explanation, although a variation of his work is also fine by me.

As for how we came to be, I believe in evolution. I don’t think we were put on the Earth ready-made by the Gods. That said, the proposal that one type of animal could descend from an animal of another type goes back to some of the first pre-Socratic Hellenic philosophers, such as Anaximander and Empedocles, so it’s not an odd frame of mind to have for a Hellenist; even the ancient Hellenes flirted with the idea that at least animal species evolved from one another. I love the myth of Prometheus, but no, that is not how I think we came to be, although I won’t rule out that the Gods had a hand in our formation through evolution.

All in all, I think Hellenismos and science go together very well. Most (if not all) scientific breakthroughs either work with Hellenic mythology or don’t detract from it. Hellenic scientific research and philosophy often forms the base of our modern understanding of the world around us. The ancient Hellenes made great contributions to the field of ‘science’. So yes, Hellenismos is 100% compatible with science and evolution, and that is something I find very appealing.

I honestly do not understand fics that depict kylo as being domineering and controlling in the bedroom when he is clearly the subbiest sub to ever sub

Like it’s so obvious in the movie that his appearance of control is all an act and what he wants more than anything is for someone to tell him what’s right and wrong and make decisions for him because he can’t trust his own judgment

He has such an intense need to please—to be useful—he spends the entire movie trying to satisfy both snoke and his grandfather’s memory and is constantly in agony over the thought of not being good enough

That mask, that robe, his cocky attitude… it’s all just posturing

SCIENTISTS GET BEST MEASURE OF STAR-FORMING
MATERIAL IN GALAXY CLUSTERS IN EARLY UNIVERSE

** Synopsis: The international SpARCS collaboration based at UC Riverside has made the best measurement yet of the amount of fuel available to form stars in clusters of galaxies located in the early universe. **

The international Spitzer Adaptation of the Red-sequence Cluster Survey (SpARCS) collaboration based at the University of California, Riverside has combined observations from several of the world’s most powerful telescopes, including W. M. Keck Observatory on Maunakea, Hawaii, to carry out one of the largest study yet of molecular gas – the raw material which fuels star formation throughout the universe – in three of the most distant clusters of galaxies ever found, detected as they appeared when the universe was only four billion years old. Allison Noble, a postdoctoral researcher at the Massachusetts Institute of Technology, led this newest research from the SpARCS collaboration.

Results were recently published in The Astrophysical Journal Letters.

Clusters are rare regions of the universe consisting of tight groups of hundreds of galaxies containing trillions of stars, as well as hot gas and mysterious dark matter.

First, the research team used spectroscopic observations from the Very Large Telescope in Chile and Keck Observatory’s powerful Multi-Object Spectrograph for Infrared Exploration (MOSFIRE) to confirm nearly a dozen galaxies were star-forming members of the three massive clusters.

“Keck Observatory’s MOSFIRE data were essential to proving conclusively that the 11 galaxies analyzed (two pairs) were indeed members of the three clusters and not foreground galaxies,” said Gillian Wilson, a professor of physics and astronomy at UC Riverside and the leader of the SpARCS collaboration.

The Tadpole Galaxy is a disrupted spiral galaxy showing streams of gas stripped by gravitational interaction with another galaxy. Molecular gas is the required ingredient to form stars in galaxies in the early universe. IMAGE CREDIT: HUBBLE LEGACY ARCHIVE, ESA, NASA AND BILL SNYDER.

Next, the researchers took images through multiple filters from NASA’s Hubble Space Telescope, which revealed a surprising diversity in the galaxies’ appearance, with some galaxies having already formed large disks with spiral arms.

One of the telescopes the SpARCS scientists used is the extremely sensitive Atacama Large Millimeter Array (ALMA) telescope capable of directly detecting radio waves emitted from the molecular gas found in galaxies in the early universe. ALMA observations allowed the scientists to determine the amount of molecular gas in each galaxy, and provided the best measurement yet of how much fuel was available to form stars.

The researchers compared the properties of galaxies in these clusters with the properties of “field galaxies” (galaxies found in more typical environments with fewer close neighbors). To their surprise, they discovered that cluster galaxies had higher amounts of molecular gas relative to the amount of stars in the galaxy compared to field galaxies. The finding puzzled the team because it has long been known that when a galaxy falls into a cluster, interactions with other cluster galaxies and hot gas accelerate the shut off of its star formation relative to that of a similar field galaxy (the process is known as environmental quenching).

“This is definitely an intriguing result,” said Wilson. “If cluster galaxies have more fuel available to them, you might expect them to be forming more stars than field galaxies, and yet they are not.”

Allison Noble, a SpARCS collaborator and this study’s leader, suggests several possible explanations: It is possible that something about being in the hot, harsh cluster environment surrounded by many neighboring galaxies perturbs the molecular gas in cluster galaxies such that a smaller fraction of that gas actively forms stars. Alternatively, it is possible that an environmental process, such as increased merging activity in cluster galaxies, results in the observed differences between the cluster and field galaxy populations.

“While the current study does not answer the question of which physical process is primarily responsible for causing the higher amounts of molecular gas, it provides the most accurate measurement yet of how much molecular gas exists in galaxies in clusters in the early universe,” Wilson said.

The SpARCS team has developed new techniques using infrared observations from NASA’s Spitzer Space Telescope to identify hundreds of previously undiscovered clusters of galaxies in the early universe.

In the future, they plan to study a larger sample of clusters. The team has recently been awarded additional time on ALMA, Keck Observatory, and the Hubble Space Telescope to continue investigating how the neighborhood in which a galaxy lives determines for how long it can form stars.