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The forensic scientist’s toolbox is growing thanks to creative methods that generate reliable leads, analyze evidence, identify suspects and solve cold cases

Longer growing seasons and increased pollen production driven by climate change could be aggravating your seasonal allergy symptoms

The next total solar eclipse to hit the United States will be in 2033, but it will only be visible in Alaska. The Lower 48 won't get one until 2044.

Video: 00:00:07

A total solar eclipse swept across North America yesterday, blocking out the Sun momentarily with parts of the continent plunged into darkness. Geostationary satellites orbiting 36 000 km away captured images of the rare celestial event. 

These images, captured by the Geostationary Operational Environmental Satellite (GOES-16), captured the moon’s shadow moving across North America from approximately 16:00 to 23:00 CEST (15:00 to 22:00 BST.)

A total solar eclipse occurs when the Moon passes between the Sun and Earth and, for a short period, blocks the face of the Sun, save for a visible ring of light, known as the Sun’s corona. 

The track of the moon’s shadow across Earth’s surface, called the path of totality, spanned across the North American continent – from Mexico to the very eastern tip of Canada.

The GOES series is a collaborative development and acquisition effort between National Oceanic and Atmospheric Administration (NOAA) and NASA. The GOES-16 (GOES-East) satellite, the first of the series, provides continuous imagery and atmospheric measurements of Earth's western hemisphere and monitors space weather.

The Copernicus Sentinel-3 mission also captured images of the eclipse with its Sea and Land Surface Temperature Radiometer (SLSTR).

The eclipse also acts as a laboratory for researching what happens to weather when the Moon’s shadow passes over. The shadow makes air temperatures drop and can cause clouds to evolve in different ways. Data from GOES, Sentinel-3 and other satellites are now being used to explore these effects.

Releasing 1 gigatonne of ground-up olivine on coastal shelves each year could help lower atmospheric carbon dioxide levels, find researchers, but questions remain over the ecological impact

Releasing 1 gigatonne of ground-up olivine on coastal shelves each year could help lower atmospheric carbon dioxide levels, find researchers, but questions remain over the ecological impact

Every month since April 2023 has been the hottest on record, as climate continues its record-breaking streak

Every month since April 2023 has been the hottest on record, as climate continues its record-breaking streak

What created this unusual celestial firework?

Only in the fleeting darkness of a total solar eclipse is the

On 8 April, a total solar eclipse passed over Mexico, the US and Canada – here are some of the most stunning images

On 8 April, a total solar eclipse passed over Mexico, the US and Canada – here are some of the most stunning images

Life on Earth depends on six critical elements: Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorous, and Sulfur. These elements are referred to as CHNOPS, and along with several trace micronutrients and liquid water, they’re what life needs.

Scientists are getting a handle on detecting exoplanets that might be warm enough to have liquid water on their surfaces, habitability’s most basic signal. But now, they’re looking to up their game by finding CHNOPS in exoplanet atmospheres.

We’re only at the beginning of understanding how exoplanets could support life. To grow our understanding, we need to understand the availability of CHNOPS in planetary atmospheres.

A new paper examines the issue. It’s titled “Habitability constraints by nutrient availability in atmospheres of rocky exoplanets.” The lead author is Oliver Herbort from the Department of Astrophysics at the University of Vienna and an ARIEL post-doctoral fellow. The paper has been accepted by the International Journal of Astrobiology.

At our current technological level, we’re just beginning to examine exoplanet atmospheres. The JWST is our main tool for the task, and it’s good at it. But the JWST is busy with other tasks. In 2029, the ESA will launch ARIEL, the Atmospheric Remote-sensing Infrared Exoplanet Large survey. ARIEL will be solely focused on exoplanet atmospheres.

An artist’s impression of the ESA’s Ariel space telescope. During its four-year mission, it’ll examine 1,000 exoplanet atmospheres with the transit method. It’ll study and characterize both the compositions and thermal structures. Image Credit: ESA

In anticipation of that telescope’s mission, Herbort and his co-researchers are preparing for the results and what they mean for habitability. “The detailed understanding of the planets itself becomes important for interpreting observations, especially for the detection of biosignatures,” they write. In particular, they’re scrutinizing the idea of aerial biospheres. “We aim to understand the presence of these nutrients within atmospheres that show the presence of water cloud condensates, potentially allowing the existence of aerial biospheres.”

Our sister planet Venus has an unsurvivable surface. The extreme heat and pressure make the planet’s surface uninhabitable by any measure we can determine. But some scientists have proposed that life could exist in Venus’ atmosphere, based largely on the detection of phosphine, a possible indicator of life. This is an example of what an aerial biosphere might look like.

This artistic impression depicts Venus. Astronomers at MIT, Cardiff University, and elsewhere may have observed signs of life in the atmosphere of Venus by detecting phosphine. Subsequent research disagreed with this finding, but the issue is ongoing. Image Credits: ESO (European Space Organization)/M. Kornmesser & NASA/JPL/Caltech

“This concept of aerial biospheres enlarges the possibilities of potential habitability from the presence of liquid water on the surface to all planets with liquid water clouds,” the authors explain.

The authors examined the idea of aerial biospheres and how the detection of CHNOPS plays into them. They introduced the concept of nutrient availability levels in exoplanet atmospheres. In their framework, the presence of water is required regardless of other nutrient availability. “We considered any atmosphere without water condensates as uninhabitable,” they write, a nod to water’s primacy. The researchers assigned different levels of habitability based on the presence and amounts of the CHNOPS nutrients.

This table from the research illustrates the authors’ concept of atmospheric nutrient availability. As the top row shows, without water, no atmosphere is habitable. Different combinations of nutrients have different habitability potential. ‘red’ stands for redox, and ‘ox’ stands for the presence of the oxidized state of CO2, NOx, and SO2. Image Credit: Herbort et al. 2024.

To explore their framework of nutrient availability, the researchers turned to simulations. The simulated atmospheres held different levels of nutrients, and the researchers applied their concept of nutrient availability. Their results aim to understand not habitability but the chemical potential for habitability. A planet’s atmosphere can be altered drastically by life, and this research aims to understand the atmospheric potential for life.

“Our approach does not directly aim for the understanding of biosignatures and atmospheres of planets, which are inhabited, but for the conditions in which pre-biotic chemistry can occur,” they write. In their work, the minimum atmospheric concentration for a nutrient to be available is 10?9, or one ppb (part per billion.)

“We find that for most atmospheres at ( p gas, T gas) points, where liquid water is stable, CNS-bearing molecules are present at concentrations above 10?9,” they write. They also found that carbon is generally present in every simulated atmosphere and that sulphur availability increases with surface temperature. With lower surface temperatures, nitrogen (N2, NH3) is present in increasing amounts. But with higher surface temperatures, nitrogen can become depleted.

Phosphorus is a different matter. “The limiting element of the CHNOPS elements is phosphorus, which is mostly bound in the planetary crust,” they write. The authors point out that, at past times in Earth’s atmosphere, phosphorus scarcity limited the biosphere.

An aerial biosphere is an interesting idea. But it’s not the main thrust of scientists’ efforts to detect exoplanet atmospheres. Surface life is their holy grail. It should be no surprise that it still comes down to liquid water, all things considered. “Similar to previous work, our models suggest that the limiting factor for habitability at the surface of a planet is the presence of liquid water,” the authors write. In their work, when surface water was available, CNS was available in the lower atmosphere near the surface.

But surface water plays several roles in atmospheric chemistry. It can bond with some nutrients in some circumstances, making them unavailable, and in other circumstances, it can make them available.

“If water is available at the surface, the elements not present in the gas phase are stored in the crust condensates,” the authors write. Chemical weathering can then make them available as nutrients. “This provides a pathway to overcome the lack of atmospheric phosphorus and metals, which are used in enzymes that drive many biological processes.”

Artist’s impression of the surface of a hycean world. Hycean worlds are still hypothetical, with large oceans and thick hydrogen-rich atmospheres that trap heat. It’s unclear if a world with no surface can support life. Image Credit: University of Cambridge

This complicates matters on worlds covered by oceans. Pre-biotic molecules might not be available if there’s no opportunity for water and rock to interact with the atmosphere. “If indeed it can be shown that life can form in a water ocean without any exposed land, this constraint becomes weaker, and the potential for the surface habitability becomes mainly a question of water stability,” the authors write.

Some of the models are surprising because of atmospheric liquid water. “Many of the models show the presence of a liquid water zone in the atmospheres, which is detached from the surface. These regions could be of interest for the formation of life in forms of aerial biospheres,” Herbort and his colleagues write.

If there’s one thing that research like this shows, planetary atmospheres are extraordinarily complex and can change dramatically over time, sometimes because of life itself. This research makes some sense in trying to understand it all. Emphasizing the complexity is the fact that the researchers didn’t include stellar radiation in their work. Including that would’ve made the effort unwieldy.

The habitability issue is complicated, confounded by our lack of answers to foundational questions. Does a planet’s crust have to be in contact with water and the atmosphere for the CHNOPS nutrients to be available? Earth has a temporary aerial biosphere. Can aerial biospheres be an important part of exoplanet habitability?

But beyond all the simulations and models, as powerful as they are, what scientists need most is more data. When ARIEL launches, scientists will have much more data to work with. Research like this will help scientists understand what ARIEL finds.

The post Measuring the Atmospheres of Other Worlds to See if There are Enough Nutrients for Life appeared first on Universe Today.

During the total solar eclipse, skywatchers saw ruby-colored prominences sticking out of the moon's shadow. Here's the science of those red dots

The total solar eclipse of 2024 thrilled millions of people who turned up to watch the celestial event unfold across North America.

The next great eclipse is upon us, with viewers across North America witnessing the moon passing in front of the Sun. It’s an amazing experience, but also an opportunity to do science. Let’s talk about what we can learn from this momentous event.

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Scientific American staffers headed to locations ranging from Texas to Vermont to try to catch a glimpse of the total solar eclipse

Artificial Intelligence is making its presence felt in thousands of different ways. It helps scientists make sense of vast troves of data; it helps detect financial fraud; it drives our cars; it feeds us music suggestions; its chatbots drive us crazy. And it’s only getting started.

Are we capable of understanding how quickly AI will continue to develop? And if the answer is no, does that constitute the Great Filter?

The Fermi Paradox is the discrepancy between the apparent high likelihood of advanced civilizations existing and the total lack of evidence that they do exist. Many solutions have been proposed for why the discrepancy exists. One of the ideas is the “Great Filter.”

The Great Filter is a hypothesized event or situation that prevents intelligent life from becoming interplanetary and interstellar and even leads to its demise. Think climate change, nuclear war, asteroid strikes, supernova explosions, plagues, or any number of other things from the rogue’s gallery of cataclysmic events.

Or how about the rapid development of AI?

A new paper in Acta Astronautica explores the idea that Artificial Intelligence becomes Artificial Super Intelligence (ASI) and that ASI is the Great Filter. The paper’s title is “Is Artificial Intelligence the Great Filter that makes advanced technical civilizations rare in the universe?” The author is Michael Garrett from the Department of Physics and Astronomy at the University of Manchester.

“Without practical regulation, there is every reason to believe that AI could represent a major threat to the future course of not only our technical civilization but all technical civilizations.”

Michael Garrett, University of Manchester

Some think the Great Filter prevents technological species like ours from becoming multi-planetary. That’s bad because a species is at greater risk of extinction or stagnation with only one home. According to Garrett, a species is in a race against time without a backup planet. “It is proposed that such a filter emerges before these civilizations can develop a stable, multi-planetary existence, suggesting the typical longevity (L) of a technical civilization is less than 200 years,” Garrett writes.

If true, that can explain why we detect no technosignatures or other evidence of ETIs (Extraterrestrial Intelligences.) What does that tell us about our own technological trajectory? If we face a 200-year constraint, and if it’s because of ASI, where does that leave us? Garrett underscores the “…critical need to quickly establish regulatory frameworks for AI development on Earth and the advancement of a multi-planetary society to mitigate against such existential threats.”

An image of our beautiful Earth taken by the Galileo spacecraft in 1990. Do we need a backup home? Credit: NASA/JPL

Many scientists and other thinkers say we’re on the cusp of enormous transformation. AI is just beginning to transform how we do things; much of the transformation is behind the scenes. AI seems poised to eliminate jobs for millions, and when paired with robotics, the transformation seems almost unlimited. That’s a fairly obvious concern.

But there are deeper, more systematic concerns. Who writes the algorithms? Will AI discriminate somehow? Almost certainly. Will competing algorithms undermine powerful democratic societies? Will open societies remain open? Will ASI start making decisions for us, and who will be accountable if it does?

This is an expanding tree of branching questions with no clear terminus.

Stephen Hawking (RIP) famously warned that AI could end humanity if it begins to evolve independently. “I fear that AI may replace humans altogether. If people design computer viruses, someone will design AI that improves and replicates itself. This will be a new form of life that outperforms humans,” he told Wired magazine in 2017. Once AI can outperform humans, it becomes ASI.

Stephen Hawking was a major proponent for colonizing other worlds, mainly to ensure humanity does not go extinct. In later years, Hawking recognized that AI could be an extinction-level threat. Credit: educatinghumanity.com

Hawking may be one of the most recognizable voices to issue warnings about AI, but he’s far from the only one. The media is full of discussions and warnings, alongside articles about the work AI does for us. The most alarming warnings say that ASI could go rogue. Some people dismiss that as science fiction, but not Garrett.

“Concerns about Artificial Superintelligence (ASI) eventually going rogue is considered a major issue – combatting this possibility over the next few years is a growing research pursuit for leaders in the field,” Garrett writes.

If AI provided no benefits, the issue would be much easier. But it provides all kinds of benefits, from improved medical imaging and diagnosis to safer transportation systems. The trick for governments is to allow benefits to flourish while limiting damage. “This is especially the case in areas such as national security and defence, where responsible and ethical development should be paramount,” writes Garrett.

News reports like this might seem impossibly naive in a few years or decades.

The problem is that we and our governments are unprepared. There’s never been anything like AI, and no matter how we try to conceptualize it and understand its trajectory, we’re left wanting. And if we’re in this position, so would any other biological species that develops AI. The advent of AI and then ASI could be universal, making it a candidate for the Great Filter.

This is the risk ASI poses in concrete terms: It could no longer need the biological life that created it. “Upon reaching a technological singularity, ASI systems will quickly surpass biological intelligence and evolve at a pace that completely outstrips traditional oversight mechanisms, leading to unforeseen and unintended consequences that are unlikely to be aligned with biological interests or ethics,” Garrett explains.

How could ASI relieve itself of the pesky biological life that corrals it? It could engineer a deadly virus, it could inhibit agricultural food production and distribution, it could force a nuclear power plant to melt down, and it could start wars. We don’t really know because it’s all uncharted territory. Hundreds of years ago, cartographers would draw monsters on the unexplored regions of the world, and that’s kind of what we’re doing now.

This is a portion of the Carta Marina map from the year 1539. It shows monsters lurking in the unknown waters off of Scandinavia. Are the fears of ASI kind of like this? Or could ASI be the Great Filter? Image Credit: By Olaus Magnus – http://www.npm.ac.uk/rsdas/projects/carta_marina/carta_marina_small.jpg, Public Domain, https://commons.wikimedia.org/w/index.php?curid=558827

If this all sounds forlorn and unavoidable, Garrett says it’s not.

His analysis so far is based on ASI and humans occupying the same space. But if we can attain multi-planetary status, the outlook changes. “For example, a multi-planetary biological species could take advantage of independent experiences on different planets, diversifying their survival strategies and possibly avoiding the single-point failure that a planetary-bound civilization faces,” Garrett writes.

If we can distribute the risk across multiple planets around multiple stars, we can buffer ourselves against the worst possible outcomes of ASI. “This distributed model of existence increases the resilience of a biological civilization to AI-induced catastrophes by creating redundancy,” he writes.

If one of the planets or outposts that future humans occupy fails to survive the ASI technological singularity, others may survive. And they would learn from it.

Artist’s illustration of a SpaceX Starship landing on Mars. If we can become a multi-planetary species, the threat of ASI is diminished. Credit: SpaceX

Multi-planetary status might even do more than just survive ASI. It could help us master it. Garrett imagines situations where we can experiment more thoroughly with AI while keeping it contained. Imagine AI on an isolated asteroid or dwarf planet, doing our bidding without access to the resources required to escape its prison. “It allows for isolated environments where the effects of advanced AI can be studied without the immediate risk of global annihilation,” Garrett writes.

But here’s the conundrum. AI development is proceeding at an accelerating pace, while our attempts to become multi-planetary aren’t. “The disparity between the rapid advancement of AI and the slower progress in space technology is stark,” Garrett writes.

The difference is that AI is computational and informational, but space travel contains multiple physical obstacles that we don’t yet know how to overcome. Our own biological nature restrains space travel, but no such obstacle restrains AI. “While AI can theoretically improve its own capabilities almost without physical constraints,” Garrett writes, “space travel must contend with energy limitations, material science boundaries, and the harsh realities of the space environment.”

For now, AI operates within the constraints we set. But that may not always be the case. We don’t know when AI might become ASI or even if it can. But we can’t ignore the possibility. That leads to two intertwined conclusions.

If Garrett is correct, humanity must work more diligently on space travel. It can seem far-fetched, but knowledgeable people know it’s true: Earth will not be inhabitable forever. Humanity will perish here by our own hand or nature’s hand if we don’t expand into space. Garrett’s 200-year estimate just puts an exclamation point on it. A renewed emphasis on reaching the Moon and Mars offers some hope.

The Artemis program is a renewed effort to establish a presence on the Moon. After that, we could visit Mars. Are these our first steps to becoming a multi-planetary civilization? Image Credit: NASA

The second conclusion concerns legislating and governing AI, a difficult task in a world where psychopaths can gain control of entire nations and are bent on waging war. “While industry stakeholders, policymakers, individual experts, and their governments already warn that regulation is necessary, establishing a regulatory framework that can be globally acceptable is going to be challenging,” Garrett writes. Challenging barely describes it. Humanity’s internecine squabbling makes it all even more unmanageable. Also, no matter how quickly we develop guidelines, ASI might change even more quickly.

“Without practical regulation, there is every reason to believe that AI could represent a major threat to the future course of not only our technical civilization but all technical civilizations,” Garrett writes.

This is the United Nations General Assembly. Are we united enough to constrain AI? Image Credit: By Patrick Gruban, cropped and downsampled by Pine – originally posted to Flickr as UN General Assembly, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=4806869

Many of humanity’s hopes and dreams crystallize around the Fermi Paradox and the Great Filter. Are there other civilizations? Are we in the same situation as other ETIs? Will our species leave Earth? Will we navigate the many difficulties that face us? Will we survive?

If we do, it might come down to what can seem boring and workaday: wrangling over legislation.

“The persistence of intelligent and conscious life in the universe could hinge on the timely and effective implementation of such international regulatory measures and technological endeavours,” Garrett writes.

The post Does the Rise of AI Explain the Great Silence in the Universe? appeared first on Universe Today.

This year's first solar eclipse, the total solar eclipse 2024 has officially begun!