Occasionally I see references in Astronomy to the speed of something as “supersonic.” I’m having trouble reconciling this term with velocities typically found among astronomical objects. Wouldn’t “relativistic” be closer to the truth? Anything close to sonic speeds in Earth’s atmosphere wouldn’t cover much distance in outer space. Peter IanchiouTucson, Arizona One would certainly thinkContinue reading "What does the term ‘supersonic’ mean in astronomy?"

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Earth has many unique features for a planet, such as a magnetic field, a large moon, and plate tectonics. It’s also the only planet we know of that harbors life. These facts form the basis of the Rare Earth hypothesis, which posits that we haven’t found aliens because other planets in the Galaxy probably don’t have all the right conditions for life. 

Another characteristic of Earth is that about 30% of its surface is land and about 70% is ocean. Recently, Columbia University Assistant Professor David Kipping investigated whether the proportion of Earth’s surface covered by dry land versus ocean, or its land fraction, is another reason Earth is habitable not only for simple single-celled organisms, but also for intelligent species like humans. 

To test this hypothesis, Kipping created 4 statistical models of planets with different land fractions that intelligent aliens could potentially evolve on. First, he created an equation to describe the likelihood that a planet in its star’s habitable zone has a particular land fraction, known as a probability distribution. Kipping weighted this probability distribution toward the extreme ends, making it more likely that a planet would be covered by a single huge landmass or a single vast ocean than by a mix of both, as on Earth. 

Kipping then incorporated this land fraction probability distribution into his statistical models to calculate the probability that a random planet will have that land fraction and host intelligent life. The 4 scenarios Kipping tested were: 1) that intelligent life is more likely to emerge on land-dominated planets, 2) that it’s more likely to emerge on ocean-dominated planets, 3) that it’s more likely to emerge on planets with roughly equal amounts of land and ocean, and 4) that its emergence is independent of a planet’s land fraction. 

As a first step in determining the kinds of planets intelligent aliens would tend to emerge on, Kipping used each model to predict the probability that intelligent life would emerge on a planet with the same land fraction as Earth. He then compared these probabilities by calculating the ratios between each value. Because Earth is the only known planet with intelligent life, a model that predicted a greater probability for humanity’s existence on Earth would be more likely to reflect reality.

Kipping considered it strong evidence that a given model was more realistic than another if the ratio between 2 of them was greater than 10, meaning one model was 10 times more likely to predict the existence of Earth and humanity. Kipping found that no comparison of any 2 models passed this threshold. However, the models assuming that intelligent life prefers ocean-dominated planets or planets with a land-ocean balance were 2.5 and 3 times more likely to predict the existence of humanity than the model assuming that intelligent life prefers land-dominated planets. Additionally, the model assuming that intelligent life prefers a land-ocean balance was always more likely to predict humanity than any other model, though marginally. 

Kipping also addressed whether finding more planets with intelligent life would affect which model was deemed most realistic, for example, if scientists discovered conclusive evidence of life on Mars in its distant past. Here, Kipping identified 2 complications. First, it’s uncertain how much of Mars’s surface was once covered by water – some estimate it had a land fraction as high as 81%, while others estimate it was as low as 25%. Second, proving that Mars once had life would not prove it once had intelligent life.

Regardless, Kipping reran the models assuming that ancient Mars had a land fraction comparable to Earth’s. Adding this second data point produced ratios similar to those in the earlier Earth-only calculations, meaning it still didn’t make any single model 10 times more likely to predict the existence of humans and Martians, respectively. 

Kipping then took the 10-times threshold and reversed the calculations to find what conditions would exceed it. In doing so, he calculated that astronomers would need to find 14 other planets with intelligent life and known land fractions to robustly determine whether intelligent life is more likely to occur on desert planets, ocean planets, balanced planets, or without bias.

Kipping concluded that he can’t yet definitively state whether there is something special about Earth’s land fraction when it comes to producing intelligent species. However, Earth’s existence would suggest that intelligent life is unlikely to favor extreme desert planets, so the Milky Way probably isn’t filled with Tatooines and Jakkus. And while his analysis doesn’t debunk the Rare Earth hypothesis, it does undermine the argument that Earth’s ocean size explains why Earth is rare. 

The post Is Earth’s water why intelligent life evolved here? appeared first on Sciworthy.

Mercury reaches greatest elongation in the evening sky this month. Venus and Jupiter have a spectacular conjunction, and later in the month the Moon occults Venus. Meanwhile, Jupiter drops deeper into twilight as it sinks toward next month’s conjunction with the Sun. The morning sky hosts ever-more-prominent Saturn, while Mars and Uranus meet in Taurus.Continue reading "June 2026: What’s in the sky this month? Venus and Jupiter have a spectacular conjunction, and the Moon occults Venus"

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Nour Haydar speaks with Christopher Knaus about the BHP files – the cache of internal documents leaked to the Guardian and the ABC’s Four Corners – which show that the world’s biggest miner has war-gamed ways to massively delay decarbonisation

Additional audio in this episode was sourced by Financial Times Live

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Earth Oddities • Strange Weather Phenomena • Desert Ecosystems • Go back to Strange Sounds Death Valley is experiencing a rare superbloom, a spectacular desert event in which vast numbers of wildflowers suddenly bloom across the valley floor after rare rainfall. This is the best flowering desert phenomenon in the driest place in North America […]

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Go back to Strange Sounds · Discover more in the Newsletter Archive From sinkholes swallowing roads to the disappearance of the Aral Sea, volcanic unrest across the Ring of Fire, and light measured in billionths of a second — reality is not static. It is constantly shifting. A vehicle sinks into a sudden roadway collapse […]

The post Earth Systems Update: Sinkhole Collapse, Aral Sea Warning & Ring of Fire Activity (Feb 2026) appeared first on Strange Sounds.

Cape Canaveral Space Force Station (CCSFS) in Florida resumed operations Friday following the explosion of Blue Origin’s New Glenn rocket during a test Thursday night. Space Launch Delta 45 (SLD 45), which manages the U.S. Space Force’s Eastern Range and oversees all East Coast rocket and missile launches, said Friday that a SpaceX Falcon 9 rocket deployedContinue reading "New Glenn explosion: what it means for Blue Origin and SpaceX"

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After completing what it said was a “thorough assessment,” the FAA on Wednesday ordered SpaceX to investigate anomalies that its Super Heavy booster experienced during the 12th test flight of its behemoth Starship rocket. The aviation regulator on Tuesday was ambiguous about whether an investigation would be required into Starship Flight 12, which launched Friday evening fromContinue reading "FAA grounds SpaceX Starship after V3 debut"

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As winter’s brilliant stars slip toward the western horizon and the constellations of spring climb higher, Northern Hemisphere observers discover a quieter but richly rewarding sky. Spring is celebrated for its galaxies, yet our own Milky Way offers an equally compelling bounty of open and globular clusters. From youthful, loosely packed groups that still sparkleContinue reading "Observe spring’s star clusters"

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Exclusive: Mining giant says technology is not yet advanced enough to run a fully electrified fleet but experts say it is hooked on federal fuel tax credits

• Revealed: the internal BHP memo that slammed the brakes on world’s biggest miner’s climate push

• Read more from the BHP files investigation here

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BHP has continued to spend hundreds of millions of dollars buying diesel trucks in the Pilbara despite internal documents suggesting it would increase emissions and be “misaligned” with its decarbonisation goals.

The mining giant is Australia’s biggest consumer of diesel and trucks are its biggest single source of diesel emissions. Replacing the fleet with battery-electric trucks is considered a critical step in the multinational’s efforts to decarbonise.

While Westminster’s attention is focused on Andy Burnham and Makerfield, another pivotal byelection is taking place in Scotland’s north-east

The coming byelection in Makerfield, from where Andy Burnham aspires to make rapid progress towards Downing Street, is perhaps the most consequential in British political history. But the decision by the Scottish National party’s former Westminster leader, Stephen Flynn, to relocate to Holyrood means that another pivotal contest is taking place more than 350 miles to the north. If Makerfield is a test case for Mr Burnham and Labour’s ability to see off Reform UK, Mr Flynn’s old constituency of Aberdeen South is on the frontline of the increasingly fraught politics of North Sea oil.

Labour, despite finishing second in the 2024 general election thanks largely to anti-Tory tactical voting, will not be expecting much this time round. The ramifications of Donald Trump’s reckless war in Iran have exposed Britain’s ongoing vulnerability to fossil-fuel-related energy shocks, highlighting the practical benefits of moving to a green economy. But the knock-on effects of the closure of the strait of Hormuz have also been a gift for the Scottish Conservatives and Reform, who are framing the byelection as a local referendum on reviving oil and gas production beyond Westminster-imposed limits.

Grattan Institute calls on Labor to set policies that will further reduce the use of gas in order to meet net zero targets

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After more than a half a century of growth, the use of gas in Australia has peaked in all sectors and entered a “structural decline”. But use will need to fall fast to meet climate targets, according to new research from an influential thinktank.

The Grattan Institute warned the government had failed to acknowledge the decline and instead needed policies to further reduce gas use and avoid the need for expensive carbon capture technologies to meet net zero targets.

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Labour leadership hopeful says NI reduction for firms could ‘incentivise’ hiring, particularly of younger people

Wes Streeting has backed calls for national insurance cuts for businesses, and for the government to drill for oil and gas in the North Sea.

The former health secretary and potential Labour leadership candidate told the Sunday Times there should be a “targeted reduction” of employers’ national insurance contribution as a way to “actively incentivise” hiring, particularly of young people.

Australia is pioneering a revolution in home renewables and battery use, proving what is possible with the right policies

The timing was rich with symbolism. As intense heatwaves pummelled Europe and Asia, and oil markets around the world leapt and sputtered, the two big chimneys of one of Australia’s largest power stations were being demolished. Meanwhile, the Australian energy minister was holding a media conference to hail a fall of up to 10% in the benchmark electricity price in parts of the country.

Quietly, and with surprisingly little fanfare from the rest of the world, Australia is pioneering a revolution in home renewables and battery use, proving what is possible with the right policies. The country was already one of the global leaders in domestic solar power, with panels on one in three homes. It also remains, however, a major contributor to the climate crisis through its vast fossil fuel exports. But it is batteries that are giving Australia a new burst of speed.

Guardian investigation shows how US presidency blurs line between policy and enrichment of American ruling family and those around it

On a graffitied Sarajevo backstreet, a path leads past an overgrown patch of garden to a white door. Beyond is the registered office of a company that is on the brink of winning contracts worth more than $1bn.

AAFS Infrastructure and Energy is close to securing a concession to build and operate a pipeline across the Balkans to allow fossil gas shipped from the US to replace supplies that come from Russia. “This could be the most important infrastructure project ever in Bosnia and Herzegovina,” says one of the country’s top officials, who, like others, asks to remain anonymous to discuss sensitive negotiations.

As summers become hotter, air conditioner sales are booming. If you’re looking to invest, here’s what to consider

When a heatwave struck the UK this week, Jon Connorton, a software developer, began monitoring temperatures inside his east Hampshire terrace house. With some rooms reaching close to 40C, it was time to deploy the air conditioner. “We just wheel it out in emergencies,” he said. “We were having trouble sleeping.”

Connorton and his wife have a portable air conditioner. These plug-in devices cool interior air by removing heat from it and blowing that heat outside, typically via a large hose slung from a window or door.

Datacentres used 22% of country’s electricity last year, pushing up household bills, study suggests

Energy demand by datacentres in Ireland has added hundreds of euros to household electricity bills in a pattern that could be replicated across Europe, according to a report.

Ireland’s growing number of datacentres last year used 22% of the country’s electricity, more than all urban homes combined, according to the Central Statistics Office. The equivalent figure in the US and UK is 6%.

Energy specialists say abandoning net zero and increasing oil and gas drilling would cause more instability for Britons

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Abandoning net zero and drilling for more oil and gas in the North Sea would be a massive setback for the UK and would not help the economy, leading experts have said in response to claims by the former prime minister Tony Blair.

“This is a bizarre intervention to make during the worst May heatwave on record and when the Iran crisis is providing yet more evidence of the enormous costs of oil and gas,” said Ed Matthew, the UK programme director at the E3G thinktank. “Clean energy is cheaper energy – it protects our bills from prices skyrocketing, its running costs are virtually zero, and it doesn’t cause climate change which threatens economic collapse ... The government should ignore Blair’s ideological nonsense and focus on what works.”

With early tests suggesting the presence of crude oil, the Caribbean island has begun to debate whether it could justify becoming a producer

Jamaica is closer than ever to drilling for oil. Tests on samples from the seabed off the Caribbean island’s south coast earlier this year identified hydrocarbons, which suggest the presence of crude oil below ground.

Jamaica imports all its fuel, which costs about $1.5-2bn (£1.1bn-1.5bn) annually, depending on global oil prices. It is a persistent drag on an economy that generated $4.3bn from tourism, its biggest earner, in 2024.

More Americans are using small solar panels in their back yards or balconies as a clean way to cut their electric bills

If you feel like your electricity bill just keeps climbing, you aren’t imagining it. Since 2020, US residential energy prices have surged by about 30%, making power the largest household energy expense behind gasoline, according to the US Energy Information Administration.

But for residents like Alex Curtis, the days of feeling powerless against rising costs are coming to an end. Curtis is waging a war on his electric bill, and his new weapon of choice is a lightweight, thin-film solar panel.