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.
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São quase 6 dezenas os investigadores, académicos e profissionais da indústria que já integram a RE², uma rede de partilha e debate para os exploradores espaciais portugueses.
The post RE²: esta rede quer por em contacto os exploradores espaciais portugueses appeared first on Tek Notícias.
Researchers say the isolated white dwarfs Gandalf and Moon-Sized define a new class of stellar remnant because they share five traits, including X-ray emission. Across the immense scale of the Universe, a single unusual object can prompt astronomers to look for others like it, sometimes leading to the recognition of an entirely new class of [...]A new method could improve cosmology research by analyzing supernovae together with the galaxies that host them. An international collaboration led by scientists at the Institute of Cosmos Sciences of the University of Barcelona (ICCUB) has created a new approach that may sharpen what researchers can learn about how the Universe expands and what dark [...]Models suggest that impact-ejected material from Earth could reach Venus’ clouds and potentially survive there briefly. Panspermia is the idea that life, or the ingredients needed for life, can move through space on asteroids, comets, and other objects. If life’s building blocks appear on one planet, a powerful impact could blast material from its surface [...]Michael Guillén, a physicist who has taught at Harvard University and worked as a science editor at ABC News, has pushed a provocative claim into the public bloodstream: that the biblical Paradise may have a physical “address” in the universe. In a January 18, 2026 opinion essay for Fox News, Guillén argues that modern cosmology, […]
The post A Harvard-Trained Physicist Maps Heaven to the Edge of the Observable Universe appeared first on Curiosmos.
GPS is commonly treated as a way to find a route or track a delivery. In critical infrastructure, its quieter function is often more consequential: it distributes precise time that helps far-flung systems agree on when something happened. That shared time base supports cellular and broadband networks, parts of the electric grid, and regulated timekeeping […]
The post If GPS Went Dark, What Would Fail First? appeared first on Curiosmos.
Dark matter is one of the biggest mysteries of modern science, because we can’t see it, touch it or feel it with our current instruments, and yet, we know it’s there because we can see how it affects galaxies, and its presence is felt through its gravity. Light bends around it as it travels across […]
The post 10 Dark Matter Facts That Will Surprise You appeared first on Curiosmos.
Forty years ago, the future seemed just around the corner—and the vehicle that was going to take us there was NASA's Space Shuttle. Originally envisioned as part of a larger integrated space transportation system, the shuttle was billed as a fully reusable vehicle, totally unlike the one-and-done capsules of the fading Apollo era, capable of making monthly (and perhaps even weekly) ferry flights to low Earth orbit.
The shuttle, it was hoped, would transform human space flight from extraordinary to mundane. Brands like Coke and Pepsi were quick to hop aboard and expand the Cola Wars into space, and there were even plans to blast Sesame Street's Big Bird into orbit.
The loss of Challenger in January 1986—carrying educator Christa McAuliffe, who would have been the first private citizen in space—put the kibosh on all of that. The shuttle, while fantastically advanced, would never be the vehicle to help humankind slip all of our surly bonds, so to speak. Even operating at its most frantic peak in 1985 just before Challenger's loss, the shuttle hardware managed a maximum of nine flights in one calendar year; for most of the 1990s, it performed at five or six flights per year. Civilians in space—to say nothing of Big Bird—would have to wait.
© 20th Century Fox
Welcome to Edition 8.43 of the Rocket Report! A disclaimer: No one yet fully appreciates the ramifications of Blue Origin's New Glenn rocket explosion Thursday night on its launch pad at Cape Canaveral, Florida. What we know as of this writing is that much of Blue's sole orbital-class launch pad has been destroyed, and the New Glenn rocket will be grounded for an extended period of time. It is too soon for any hot takes, at least until the Sun rises at the Cape on Friday morning. One thing I am sure of is that we will be writing about this event for weeks, months, and years to come.
As always, we welcome reader submissions. If you don't want to miss an issue, please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets, as well as a quick look ahead at the next three launches on the calendar.
Charting China's contribution to space junk. There's a problem with the drastic uptick in Chinese space launches over the last decade. China appears to be ignoring long-established norms about disposing of the upper stages of rockets, Ars reports. These are the parts of the vehicle that separate from the first stage of a rocket and push a satellite or spacecraft into orbit. In the early decades of spaceflight, launch operators routinely left upper stages in orbit after they released their payloads. But most launch companies today reserve enough propellant in their rockets to remove them from orbit to avoid the risk of spent upper stages becoming a source of space debris. But China is not following this trend. There has been striking growth in China’s rocket body mass. In the past five years, the mass of Chinese rocket bodies in long-lived orbits has risen from less than 100 metric tons to 252, according to a new analysis by Space Domain Awareness expert Jim Shell.
© VCG/VCG via Getty Images
Thursday night's detonation of Blue Origin's New Glenn rocket during a static-fire test produced a spectacular fireball over Florida, sending shards of the rocket flying far and wide, into the sea and across the coastal scrubland nearby.
With sunrise on Friday teams from Blue Origin, the US Space Force, and NASA will be able to begin more thoroughly assessing the damage to Blue Origin's facilities and begin picking up pieces of the rocket.
— Nick Johnson (@NickJohnson315) May 29, 2026
© Blue Origin
On Thursday evening, Blue Origin attempted to test fire its massive New Glenn rocket at its Florida launch site, but something went very wrong after engine ignition. The super heavy lift rocket exploded in spectacular and disastrous fashion.
The static fire test was being filmed by NASASpaceflight.com on its Space Coast Live feed, which captured video of the conflagration that followed the destruction of the booster. The first stage of New Glenn, fueled with methane, produced a massive fireball above the launch site along the Florida coast, LC-36A. It is possibly the most dramatic and powerful rocket explosion since the Soviet Union's N1 rocket was destroyed during a launch attempt in 1969.
Blue Origin's New Glenn just blew up at LC-36 while attempting to Static Fire ahead of NG-4.https://t.co/tANS0dWyIH pic.twitter.com/PztxFoBqIw
— NSF - NASASpaceflight.com (@NASASpaceflight) May 29, 2026
© Blue Origin
It was less than two months ago that the third flight of Blue Origin's heavy-lift New Glenn rocket left a customer's payload in an unusable orbit. Investigators have now identified the cause of the failure, and Blue Origin is preparing to launch the next New Glenn mission as soon as next week.
The Federal Aviation Administration and Blue Origin announced the closure of the failure investigation May 22. Yesterday, officials confirmed Blue Origin's next launch will loft a payload of 48 commercial satellites for Amazon's broadband network in low-Earth orbit. This will be the most satellites Amazon has launched on a single rocket, surpassing previous flights on United Launch Alliance's Atlas V, SpaceX's Falcon 9, and Europe's Ariane 6.
Blue Origin and Amazon, each founded by Jeff Bezos, have not officially revealed a target launch date, but public notices of airspace and maritime closures suggest the mission is set to lift off from Cape Canaveral Space Force Station, Florida, as soon as next Thursday, June 4. Blue Origin is expected to roll the New Glenn rocket to its launch pad in the coming days for a test-firing of its seven main engines, fueled by liquified natural gas and liquid oxygen.
© Blue Origin
NASA satellites designed to observe cyclone wind speeds and collapsing ice sheets have also proven capable of identifying the approximate locations of GPS jammers. That could help monitor high-risk areas for aircraft and ships navigating the growing prevalence of GPS interference worldwide.
Two different NASA satellite systems showed how they could locate a known but mysterious GPS jammer within several kilometers of its position in Iran, according to an experiment by Sean Gorman, CEO and cofounder of the location-based technology company Zephr.xyz that was detailed in the magazine GPS World. Such jammers use strong signals to overpower the weaker radio signals coming from US-operated GPS satellites and other global navigation satellite systems.
Such NASA satellites cannot perform “near-real time monitoring” or pinpoint the exact location of GPS jammers, said Clara Chew, principal scientist and lead of the GNSS systems and data team at the California-based satellite manufacturer Muon Space, who was not involved in the study. But Chew told Ars that identifying the approximate locations of GPS jammers “could potentially be helpful for flight planning” or for “indicating high risk areas for maritime shipping.”
© NASA/JPL-Caltech
SpaceX has won a lucrative contract to provide the US military with a means of distributing space-based sensing and targeting data, forming the "backbone" of a rearchitected network after separate Pentagon initiatives stalled, officials announced Tuesday.
Space Systems Command, the Space Force's primary procurement and acquisition center, announced the $2.29 billion firm-fixed-price agreement, confirming long-simmering reports that the Pentagon was likely to tap SpaceX for a new communications network in low-Earth orbit. SpaceX's selection for the Space Data Network (SDN) Backbone contract "accelerates the delivery of a resilient, high-speed communications network in space," Space Systems Command said in a statement.
The network will be based on technology originally developed for SpaceX's Starlink global Internet constellation. SpaceX already builds and launches specially designed satellites, called Starshield, for military applications. The SDN Backbone network in low-Earth orbit (LEO) will presumably use the Starshield platform.
© US Space Force/Gwendolyn Kurzen
NASA officials announced contract awards for the initial elements of a lunar base on Tuesday, including two rovers that will provide mobility to astronauts.
With the series of announcements, NASA Administrator Jared Isaacman sought to maintain momentum around a Moon Base initiative revealed two months ago as part of the space agency's return to the Moon. "For those waiting patiently, the grand return is close at hand, and we will not slow down," he said.
The manager for the lunar base, Carlos Garcia-Galan, said the space agency had selected two companies, Astrolab and Lunar Outpost, to build approximately 1-ton rovers that would be ready for delivery to the Moon in 2028. Astrolab will receive $219 million for its "CLV-1" rover, and Lunar Outpost $220 million for its "Pegasus" rover, building upon initial contracts awarded two years ago. Each rover is expected to have a range of 200 km and be capable of driving autonomously, with guidance from operators on Earth, in addition to being driven by astronauts.
© NASA
Up until a decade ago, China had never launched as many as 20 orbital rockets a year. But beginning in 2022, the Asian country launched 64 rockets and last year reached a record total of 93, marking it as the second-most productive space power in the world.
Further growth is anticipated from both the company's state-owned enterprises as well as a rapidly expanding number of private launch companies. There is nothing wrong with this, as China's rapid growth in launch has been mirrored by the United States and, in particular, SpaceX.
However there is an issue with these launches, as China appears to be ignoring long-established norms about disposing of the upper stages of rockets. These are the parts of the vehicle that separate from the first stage of a rocket and push a satellite or spacecraft into orbit.
© Jim Shell
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