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Earth Might Be Sitting in a Massive ‘Supervoid’ in Space

When we gaze out into the cosmos beyond the borders of the Milky Way, we behold multitudes. Space is teeming with galaxies, speckled across the darkness like stars. If we stopped there, it would be easy to assume that the distribution of galaxies is more or less even throughout space-time.

But there’s some method to the madness: rather than wheeling freely about, galaxies tend to concentrate into clusters and clumps and filaments of the cosmic web, attracted by mutual gravity into matter highways, superhighways and nodes.

The inverse of that is voids – regions of significantly lower density, with relatively few galaxies.

Earth’s First Crust Was Continental — Long Before Plate Tectonics Began

New research suggests that Earth’s first crust, formed over 4.5 billion years ago, already carried the chemical traits we associate with modern continents. This means the telltale fingerprints of continental crust didn’t need plate tectonics to form, turning a long-standing theory on its head.

Using simulations of early Earth conditions, scientists found that the intense heat and molten environment of the planet’s infancy created these signatures naturally. The finding shakes up how we understand Earth’s evolution and could even influence how we think about crust formation on other planets.

A surprising shift in earth’s history.

JWST captures its first direct images of carbon dioxide outside solar system

The James Webb Space Telescope has captured its first direct images of carbon dioxide in a planet outside the solar system in HR8799, a multiplanet system 130 light-years away that has long been a key target for planet formation studies.

The observations provide strong evidence that the system’s four giant planets formed in much the same way as Jupiter and Saturn, by slowly building solid cores. They also confirm Webb can do more than infer atmospheric composition from starlight measurements—it can directly analyze the chemistry of exoplanet atmospheres.

“By spotting these strong carbon dioxide features, we have shown there is a sizable fraction of heavier elements, such as carbon, oxygen, and iron, in these planets’ atmospheres. Given what we know about the star they orbit, that likely indicates they formed via core accretion, which for planets that we can directly see is an exciting conclusion,” said William Balmer, a Johns Hopkins University astrophysicist who led the work.

Infrared heavy-metal-free quantum dots deliver sensitive and fast sensors for eye-safe LIDAR applications

The frequency regime lying in the shortwave infrared (SWIR) has very unique properties that make it ideal for several applications, such as being less affected by atmospheric scattering as well as being “eye-safe.” These include Light Detection and Ranging (LIDAR), a method for determining ranges and distances using lasers, space localization and mapping, adverse weather imaging for surveillance and automotive safety, environmental monitoring, and many others.

However, SWIR light is currently confined to niche areas, like scientific instrumentation and military use, mainly because SWIR photodetectors rely on expensive and difficult-to-manufacture materials. In the past few years, —solution-processed semiconducting nanocrystals—have emerged as an alternative for mainstream consumer electronics.

While toxic heavy-metals (like lead or mercury) have typically been used, quantum dots can also be made with environmentally friendly materials such as silver telluride (Ag2Te). In fact, silver telluride colloidal quantum dots show device performance comparable to their toxic counterparts. But they are still in their infancy, and several challenges must be addressed before they can be used in practical applications.

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