Lifeboat Foundation

The highest rung on the ladder is studied by analyzing the redshifts of distant galaxies. This technique can be used to measure distances across of billions of light-years, by contrast.

Redshift occurs because, as objects race away from us due to the expansion of the universe, the light they emit that takes billions of years to travel to us has its wavelength stretched by this expansion. That lengthening reddens the light and even causes it to move to infrared wavelengths sometimes. This is actually why the James Webb Space Telescope (JWST), which is highly sensitive to infrared light, is so adept and seeing galaxies in the early universe.

The cosmic distance ladder can help cosmologists measure the rate at which the universe is expanding, a value called the Hubble constant, named in honor of astronomer Edwin Hubble. This is because his observations of distant galaxies were key in overturning the idea that the universe exists in a steady state, neither growing nor shrinking.

Diamond is the strongest material known. However, another form of carbon has been predicted to be even tougher than diamond. The challenge is how to create it on Earth.

The eight-atom body-centered cubic (BC8) crystal is a distinct carbon phase: not diamond, but very similar. BC8 is predicted to be a stronger material, exhibiting a 30% greater resistance to compression than diamond. It is believed to be found in the center of carbon-rich exoplanets. If BC8 could be recovered under ambient conditions, it could be classified as a super-diamond.

This crystalline high-pressure phase of carbon is theoretically predicted to be the most stable phase of carbon under pressures surpassing 10 million atmospheres.

In preparation for a permanent human colony on the Moon, DARPA has awarded a contract to Northrop Grumman to develop a lunar railway concept, as part of the 10-year Lunar Architecture (LunA-10) Capability Study.

Running a train on the Moon may seem profoundly silly, but there is some very firm logic behind it. Even as the first astronauts were landing on the Sea of Tranquility in 1969, it was realized that a permanent human presence on Mars would require an infrastructure to maintain it. That includes mines for water ice, nuclear power plants, factories, and railways.

Though many people think the Moon is small, it is, in fact, a very large place with a surface area equivalent to that of Africa. Over such an expanse, even a limited presence would require some sort of a transport system to link various outposts and activities.

Human brain organoids are an intrinsically self-organized neuronal ensemble grown from three-dimensional assemblies of human-iPSCs. As shown here, brain organoids offer a window into the complex neuronal activity that emerges from intrinsically-formed circuits capable of mirroring aspects of the developing human brain³². Applying high-density CMOS MEA to large multi-cellular networks spanning millimeters of the brain organoid cross-sections we isolated single-unit activity and computed the timing of successive action potentials not due to refractoriness referred to as ISIs. As observed in neocortical neurons in vivo, we observed action potentials with irregular ISI’s that followed a Poisson-like process. From a set of 224 neurons analyzed from four different organoids, 16% ± 8% of the total units fit a Poisson distribution (Fig. 3) with, by definition, the CV approaches one for a perfectly homogenous Poisson process, whereas purely periodic distributions have CV values of zero. Thus, a minority fraction of ISIs were highly irregular (Fig. 3), whereas a majority displayed comparatively more regular spiking patterns with less variation (denoted by a lower CV), which may function to send lower-noise spike-rate signals. ISI distributions have also been fitted to gamma distributions that are mathematically equivalent to an exponential distribution when the shape parameter (k) is one and converges to a normal distribution for large k, thus providing a useful measure of ISI-regularity similar to the CV²⁸. Depending on architectonically defined brain regions with specialized cellular compositions and intrinsic circuitry, neurons process information differently^67,68,69. Indeed, neuronal firing varies considerably across cortical regions of monkeys^28,70,71. Therefore, different organizational features across the brain organoid may exhibit different dynamics to account for the observed ISI distributions. The minority fraction of irregular ISI distributions may be a feature of higher levels of entropy and circuit complexity and contain increased capacity for computation and information transfer as found in prefrontal cortex compared to more regular firing patters found in motor regions²⁸.

We derived a graph of weighted edges that couple single unit node pairs to send and receive spikes over a wide spatial range. Due to the thickness of our organoid slices, many neurons in the slice are too far from any electrode for their spikes to be detected⁵³. Thus, we cannot rule out the possibility that intermediate undetected neurons may account for the coupling between two correlated units. The graph does not imply downstream or upstream routes of information transfer beyond the individual binary couplings. Importantly, what the network does demonstrate is a non-random pattern of a relatively small number of statistically strong (reliable) couplings against a backdrop of weaker couplings. As demonstrated in the murine brain^51,52, high anatomical connection strength edges shape a non-random framework against a background of weaker ones (Fig. 6 and Supplementary Fig. 14). The majority of the singe units (nodes), which we refer to as brokers, have large proportions of incoming and outgoing edges. The dynamic balance among receivers and senders could likely reflect short-term plasticity⁷².

Brain organoids—composed of roughly one million cells—have neuronal assemblies of sufficient size, cellular orientation, connectivity and co-activation capable of generating field potentials in the extracellular space from their collective transmembrane currents. The basis for low frequency LFPs may be the cellular diversity that emerges in the organoid from the variety of GABAergic cells (Fig. 2), consistent with their role in the generation of highly correlated activity networks detected as LFPs³¹, parvalbumin cells (Fig. 2c), associated with sustaining network dynamics⁷³, and axon tracts that extended over millimeters (Fig. 2b). Coherence of theta oscillations over spatial extents of the organoid was observed and was unlikely due to volume conduction from distant sources, as happens in EEG and MEG measurements⁵⁴, because the voltage recordings were conducted within a small tissue volume (≈3.5 mm³). Consistent with minimal volume conduction effects, we validated theta oscillations by demonstrating that the imaginary part of coherency⁵⁴ projected onto the same spatial locations identified by cross-correlation analysis (Supplementary Fig. 19). Correlations between theta oscillations and local neuronal firing (Fig. 7) strongly supported a local source for the rhythmic activity^19,20,53. The local volume through which theta dispersed extended to the z-dimension as shown with the Neuropixels shank (Fig. 9).

Open any astronomy textbook to the section on white dwarf stars and you’ll likely learn that they are “dead stars” that continuously cool down over time. New research published in Nature is challenging this theory, with the University of Victoria (UVic) and its partners using data from the European Space Agency’s Gaia satellite to reveal why a population of white dwarf stars stopped cooling for more than eight billion years.

“We discovered the classical picture of all white dwarfs being dead stars is incomplete,” says Simon Blouin, co-principal investigator and Canadian Institute of Theoretical Astrophysics National Fellow at UVic.

“For these white dwarfs to stop cooling, they must have some way of generating extra energy. We weren’t sure how this was happening, but now we have an explanation for the phenomenon.”

Calling all stargazers: Oregon is now home to the largest Dark Sky Sanctuary in the world.

Earlier this month, DarkSky International certified a remote, 2.5 million-acre area in the southeastern part of the state. From this rugged swath of high desert landscape dotted with sagebrush, visitors who stay up late can see large numbers of stars, planets and other celestial bodies.

“It’s surprising sometimes to see that many stars all at once,” says Bob Hackett, executive director of Travel Southern Oregon, to the Guardian’s Dani Anguiano. “It catches you, and it makes you pause because you feel like you can touch it … That vastness of the whole cosmos up there—it almost makes you get closer to the people you’re with on the ground.”

The study of “exoplanets,” the sci-fi-sounding name for all planets in the cosmos beyond our own solar system, is a pretty new field. Mainly, exoplanet researchers like those in the ExoLab at the University of Kansas use data from space-borne telescopes such as the Hubble Space Telescope and Webb Space Telescope. Whenever news headlines offer findings of “Earth-like” planets or planets with the potential to support humanity, they’re talking about exoplanets within our own Milky Way.

Jonathan Brande, a doctoral candidate in the ExoLab at the University of Kansas, has just published findings in the open-access scientific journal The Astrophysical Journal Letters showing new atmospheric detail in a set of 15 exoplanets similar to Neptune. While none could support humanity, a better understanding of their behavior might help us to understand why we don’t have a small Neptune, while most solar systems seem to feature a planet of this class.

“Over the past several years at KU, my focus has been studying the atmospheres of exoplanets through a technique known as transmission spectroscopy,” Brande said. “When a planet transits, meaning it moves between our line of sight and the star it orbits, light from the star passes through the planet’s atmosphere, getting absorbed by the various gases present. By capturing a spectrum of the star — passing the light through an instrument called a spectrograph, akin to passing it through a prism — we observe a rainbow, measuring the brightness of different constituent colors. Varied areas of brightness or dimness in the spectrum reveal the gases absorbing light in the planet’s atmosphere.”

The Einasto Supercluster is so vast that it would take a light signal 360 million years to get from one end to the other.

Understanding how a thermonuclear flame spreads across the surface of a neutron star—and what that spreading can tell us about the relationship between the neutron star’s mass and its radius—can also reveal a lot about the star’s composition.