Lifeboat Foundation

Two decades of monitoring from W. M. Keck Observatory on Mauna Kea in Hawaiʻi reveals a peculiar cloud dubbed X7 being pulled apart as it accelerates toward the supermassive black hole at the center of our Milky Way galaxy.

Astronomers from the UCLA Galactic Center Orbits Initiative (GCOI) and Keck Observatory have been tracking the evolution of this dusty gas filament since 2002; high-angular resolution near-infrared images captured with Keck Observatory’s powerful adaptive optics system show X7 has become so elongated that it now has a length of 3,000 times the distance between the Earth and sun (or 3,000 astronomical units).

Continue reading “The swan song of a cloud approaching the Milky Way’s supermassive black hole” »

Two groups demonstrate innovative ways to capture the ultrafast motion of electrons in atoms and molecules.

Electrons move so quickly inside of atoms and molecules that they are challenging to “capture on film” without blurring the images. One way to take fast snapshots is to ionize an atom or molecule and then use the released electrons as probes of the cloud out of which they originate. Now Gabriel Stewart at Wayne State University in Michigan and colleagues [1] and Antoine Camper at the University of Oslo in Norway and colleagues [2] have improved this “self-probing” technique. The demonstrations could lead to a better understanding of the electron motion that underpins many fundamental processes.

Scientists need to complete three key tasks to measure the evolution of an electron cloud that moves and changes on an ultrafast timescale. The first is to exactly record the beginning of the evolution—analogous to pressing “start” on a mechanical stopwatch. The second is to track how much time has gone by since the starting event—analogous to precisely measuring the ticking of the stopwatch’s second hand. And the third is to take a quick snapshot of the electron cloud so that it looks frozen in time.

The European mole, equipped with its formidable digging shovels, can effortlessly tunnel through the earth. The same holds true for the Australian marsupial mole. Despite residing in vastly different regions, the two species.

A species is a group of living organisms that share a set of common characteristics and are able to breed and produce fertile offspring. The concept of a species is important in biology as it is used to classify and organize the diversity of life. There are different ways to define a species, but the most widely accepted one is the biological species concept, which defines a species as a group of organisms that can interbreed and produce viable offspring in nature. This definition is widely used in evolutionary biology and ecology to identify and classify living organisms.

Traditionally we’ve been taught the Earth has four primary layers. Though, a distinct change at depth suggests there’s another.

Fresh evidence concerning the possibility that Earth’s inner core has a separate inner core of its own was published in Nature Communications.

In the new study, Thanh-Son Phạm and Hrvoje Tkalčić from the Australian National University collated data from existing probes.

Continue reading “Earth’s hiding fifth layer in its inner core, reveals fresh evidence” »

Scientists from The Ohio State University have a new theory about how the building blocks of life—the many proteins, carbohydrates, lipids and nucleic acids that compose every organism on Earth—may have evolved to favor a certain kind of molecular structure.

It has to do with a concept called chirality. A geometric property inherent to certain molecules, chirality can dictate a molecule’s shape, chemical reactivity, and how it interacts with other matter. Chirality is also sometimes referred to as handedness, as it can be best described as the dichotomy between our hands: Though they are not identical, the right and the left hand are mirror images of each other, and can’t be superimposed, or exactly overlaid on one another.

In the journal ACS Earth and Space Chemistry, researchers now propose a new model of how the molecules of life may have developed their “handedness.”

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Our DNA holds thousands of dead genes and we’ve only just begun to unravel their stories. But one thing is already clear: we’re not just defined by the genes that we’ve gained over the course of our evolution, but also by the genes that we’ve lost along the way.

Thanks to these illustrators for their wonderful hominin illustrations featured throughout this episode!
Julio Lacerda: https://twitter.com/JulioTheArtist.
Fabrizio de Rossi: https://www.facebook.com/ArtofFabricious/
Jack Byrley: https://twitter.com/bedupolker.

Continue reading “The Genes We Lost Along the Way” »

This process is no less relevant to humans than any other species in nature, but since our species is such an evolutionary newcomer, the extent of its influence — and how it might work today — is still difficult to pin down.

The challenge: A team of researchers in Greece and Ireland, led by Nikolaos Vakirlis at the Alexander Fleming Biomedical Sciences Research Center in Athens, argues that a key to understanding human evolution lies with short sequences of DNA named “open reading frames” (ORFs). These structures are small sections of the genome that encode tiny protein molecules — microproteins — which can perform a diverse range of crucial biological tasks, from regulating muscle performance to alerting cells to damaging stresses.

Due to their minuscule sizes, ORFs are notoriously difficult to study. Because of this, their full relevance has gone under the radar in mainstream genomics research until recently, and even today, they still aren’t considered to be proper genes in themselves. For Vakirlis’ team, this potential oversight masks the fact that the microproteins encoded by ORFs can develop their own de novo sequences over generations, which may eventually develop into new genes.

A new study has identified seven spider species previously unknown to science in the depths of Israeli caves, with the surprise finding that they are evolutionarily closer to arachnids found in southern Europe than to their neighbors at cave entrances in Israel.

The peer-reviewed research, published in the Molecular Phylogenetics and Evolution journal, was conducted by scientists from the Hebrew University in Jerusalem and the University of Madison-Wisconsin.

The study “has extensive scientific implications for uncovering the evolution of speciation in caves and the historical, geographic and climatic processes that occurred in Israel,” the Hebrew University said in a statement.

Interstellar dust captures a significant fraction of elements heavier than helium in the solid state and is an indispensable component both in theory and observations of galaxy evolution.

Dust emission is generally the primary coolant of the interstellar medium (ISM) and facilitates the gravitational collapse and fragmentation of gas clouds from which stars form, while altering the emission spectrum of galaxies from ultraviolet (UV) to far-infrared wavelengths through the reprocessing of starlight. However, the astrophysical origin of various types of dust grains remains an open question, especially in the early Universe.

Here we report direct evidence for the presence of carbonaceous grains from the detection of the broad UV absorption feature around 2175A˚ in deep near-infrared spectra of galaxies up to the first billion years of cosmic time, at a redshift (z) of ∼7. This dust attenuation feature has previously only been observed spectroscopically in older, more evolved galaxies at redshifts of z3. The carbonaceous grains giving rise to this feature are often thought to be produced on timescales of hundreds of millions of years by asymptotic giant branch (AGB) stars. Our results suggest a more rapid production scenario, likely in supernova (SN) ejecta.