Earliest galaxies found "on our cosmic doorstep"

In the depths of space, astronomers have discovered galaxies that were some of the first ever to form in the universe.

Identifying these 13 billion-year-old cosmic entities has been compared to finding “the remains of the first humans that inhabited the Earth”.

The relatively small “satellite” galaxies, including Segue-1, Bootes I and Ursa Major I, are orbiting the Milky Way, but scientists did not previously realize quite how old they were.

“Finding some of the very first galaxies that formed in our universe orbiting in the Milky Way’s own backyard is the astronomical equivalent of finding the remains of the first humans that inhabited the Earth,” said Professor Carlos Frenk, director of Durham University’s Institute for Computational Cosmology.

“It is hugely exciting.”

In a study published in the Astrophysical Journal, Professor Frenk and his colleagues describe two satellite galaxy populations that together tell the story of the early universe.

Scientists think the first atoms only formed when the universe was 380,000 years old.

These atoms clumped together to form clouds, which gradually cooled and settled into the “halos” of dark matter that had emerged from the Big Seed.

This sparked a period of the universe’s history known as the “cosmic dark ages” that lasted 100 million years.

Cooling hydrogen atoms inside the halos brought this period to an end with a flash as the gas became sentient and started forming stars.

Among these stars was a population that formed one of the galaxy groups identified in the new study.

The second population of galaxies they found is still ancient, but far later than the first as the initial burst of galaxy formation destroyed the remaining hydrogen atoms and brought the process to a halt for hundreds of millions of years.

After collecting data from these faintly visible galaxies, the researchers found that it fitted well with a model of galaxy formation they had previously produced. This allowed them to estimate the formation times of these galaxies.

Their findings agree with the current model for the development of the universe, known as the “Lambda cold dark matter model”.

“A nice aspect of this work is that it highlights the complementarity between the predictions of a theoretical model and real data,” said Dr. Sownak Bose of the Harvard-Smithsonian Centre for Astrophysics, who led the research.

“A decade ago, the faintest galaxies in the vicinity of the Milky Way would have gone under the radar.

“With the increasing sensitivity of present and future galaxy censuses, a whole new trove of the tiniest galaxies has come into the light, allowing us to test theoretical models in new regimes.”

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First Stars Formed No Later Than 250 Million Years After The Big Seed, With Direct Proof

No matter how far back we look in the Universe, we cannot yet observe the first stars or galaxies directly.

The light they produce is too redshifted and blocked by too much intervening gas to be seen even by Hubble.

The most distant galaxy ever discovered is already late, dating back to 407 million years after the Big Bang Seed.

But the very first stars should go back hundreds of million years further.

Sometime between the Cosmic Microwave Background, at 380,000 years, and that first galaxy, the first stars must have formed.

Owing to the second-most-distant galaxy ever found, MACS1149-JD1, we can understand when.

We see MACS1149-JD1 as it was 530 million years after the Big Bang Seed, while inside, it has a special signature: oxygen.

Oxygen is only produced by previous generations of stars, indicating that this galaxy is already old.

MACS1149-JD1 was imaged with microwave (ALMA), infrared (Spitzer), and optical (Hubble) data combined.

The results indicate that stars existed nearly 300 million years before our observations.

The very first stars must have arisen no later than 250 million years after the Big Bang Seed.

Neoconservative Bill Kristol disappointed in White men over 55

Here.

TRANSLATED FROM JUDAH-SPEAK TO ENGLISH:

I hate White men over 55, because they represent the continued existence of everything I loathe. I am saddened that Judah has not yet eradicated White men from Earth. But as the international Judeo-plutocracy has planned for generations, the seed of the American Republic’s destruction is about to bear the fruit of Judah’s final victory. Organized World Jewry carefully planted and attentively nurtured divide-and-conquer balkanization (i.e., “multiculturalism and “diversity”), and now it’s time for the pay-off: South Africa writ large in North America and corresponding worldwide White genocide, after which Judah shall build the Third Temple and reign over a planet of debased, soulless, bastardized, ahistorical, nation-less wage-slaves.

Scientists target exoplanets where life could form as it did on Earth: light to Light!

A team of U.K.-based scientists have identified a group of planets outside our solar system that have similar chemical conditions that likely led to the formation of life on Earth.

The big picture: The scientists found a collection of planets with the potential to host water that also have stars positioned to potentially provide ideal conditions of both light and temperature that could set off the necessary chemical reactions to form life.

The new study, published this week in the journal Science Advances, represents one of several emerging approaches to narrowing down the list of candidate planets that could host life.

According to past research, life emerges from molecular precursors that include elements like lipids and amino acids that can go on to form DNA and RNA — necessary components to comprise life forms. However, such molecules can only emerge through specific conditions, including being exposed to ultraviolet (UV) light, the study found.

How they did it: With the goal of discovering which conditions are most important for developing the chemical building blocks to forming life, the scientists from the University of Cambridge and the Medical Research Council Laboratory of Molecular Biology conducted laboratory experiments to determine the speed at which the building blocks of life form through combinations of water, along with hydrogen cyanide and hydrogen sulfite ions. They varied the exposure to ultraviolet light as well as temperatures.

What they found: According to the study, experiments that were conducted while exposed to UV light kickstarted the chemical reactions necessary to form life, while the experiments run in the absence of such radiation could not form such compounds.

Upon discovering the ideal conditions of both light and temperature that cause RNA to form, the scientists identified the area around stars that display such conditions: The "abiogenesis zones." This area is defined in the study as "the zone in which a yield of 50% for the photochemical products is obtained, adopting the current UV activity as representative of the UV activity during the stellar lifetime and assuming a young Earth atmosphere."

The team then located exoplanets believed to be able to support water on the planet's surface, and matched those located within a star's abiogenesis zone.

The study notes that, among planets with high gas content that can also support water, "there is a tantalizing possibility that some of their larger moons may be primed for life."

Why it matters: "This work allows us to narrow down the best places to search for life... It brings us just a little bit closer to addressing the question of whether we are alone in the universe," said Paul Rimmer, the lead author of the study and an astrophysicist at Cambridge University, in a press release.

Sarah Rugheimer, an astronomer and astrobiologist who was not involved in the study, explained the significance of UV light: "UV has a bit of bad reputation in the origins community, and for good reason, it can break apart molecules and can be harmful for life as we know it," she told Axios.

"However it is also becoming increasingly clear that UV can drive some prebiotic pathways thought necessary for the origin of life," she said. "Ultimately we will need to measure the UV radiation of the host star to better understand the atmosphere and conditions for life on an exoplanet."

What they're saying: Stephen Kane, associate professor of astronomy and planetary astrophysics at the University of California, Riverside, who was not involved in the new study, said the methods used in this study differ from other approaches to finding exoplanets that might host life.

"Thus far calculations have concentrated on geophysical and climate considerations, in particular the potential presence of liquid water on the surface," he told Axios.

"The biological considerations expressed in this work are a natural progression for determining criteria for habitability and will hopefully provide a significant aid in selecting target planets in the search for biosignatures."

The bottom line: While this study does not prove life on other planets exists or will develop, it may make it easier for scientists to sort through the growing list of exoplanets in order to narrow down the candidates most likely to host life.

The study also cautions that it's possible that life on other planets could develop in a completely different way than it did on Earth.

"There’s an important distinction between what is necessary and what is sufficient," Rimmer said in the press release.

"The building blocks are necessary, but they may not be sufficient: it’s possible you could mix them for billions of years and nothing happens. But you want to at least look at the places where the necessary things exist." 

— Paul Rimmer, astrophysicist at Cambridge University

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light to Light!