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For years, the idea of nuclear weapons in space sounded more like science fiction than a realistic threat. That changed Monday (Sept. 14), when U.S. Air Force Secretary Troy Meink announced at the Air, Space and Cyber Conference in Maryland that the U.S. had deployed "on-orbit space control weapons capable of defending the Joint Force against hostile adversary action."

While the officials have not said that these weapons are nuclear, the announcement has raised a question: If countries are now openly putting weapons in space, how far away are we from a future where nuclear weapons become part of that competition?

The concerns about nukes in space goes back to the 1960s. In 1967, the U.S. and the Soviet Union signed the Outer Space Treaty, in which the nations agreed to not place nuclear weapons or other weapons of mass destruction in orbit around Earth. But this treaty never included an enforcement mechanism — and now, that tenuous compromise may have been violated entirely, inviting other countries to add their own weapons to the final frontier.

With the U.S.' recent announcement, are you worried about an arms race in space? Vote in our poll below, and leave your thoughts in the comments.

'> Are you worried about the US deploying weapons in space?

Live Science recently polled readers on whether they would want a humanoid robot doing their household chores, and the results reveal just how appealing the idea of a robotic housekeeper really is.

As of Sept. 15, over 600 people had responded, with 42% choosing to let the robot "take my chores, please." This pattern was reflected in the comments, with one reader stating, "I would, but I doubt my wife would approve of the job the robot did." To this, another reader responded, "Good for her. Take her household responsibilities for a year and report back."

Thirty-six percent of voters, the next-largest bloc, chose the opposite answer: "No, I don't trust it with my dishes (or data)." Humanoid robots are taught movements and tasks by building world models from the environments around them. While the technology remains primitive — resulting in some clumsy (albeit hilarious) mechanical failures — this, rather than privacy concerns, seems to be the current focus of deploying these machines.

It's these mechanical concerns that other commenters focused on, with one reader writing, "I don't think robots are dexterous enough to do dusting chores. Maybe vacuuming, but probably slow and clumsy moving furniture."

The reader also cast doubt on washing floors and moving furniture to mop hard floors ‪—‬ could it discern between items that could and couldn't be loaded into the dishwasher?

"Maybe robots can maintain houseplants," they continued. "Certainly, equipped with a moisture meter and a huge horticultural database, robots can probably serve a better role as waterers in huge commercial nurseries…"

'> 'Maybe robots can maintain houseplants': Readers react to letting humanoid robots take over their housework

Major cities like Antioch, Ancyra (modern-day Ankara) and Byzantium in what is now Turkey, as well as Corinth in Greece, were "better located than Rome" for those traveling by land, the team wrote in a paper published Tuesday (Sept. 15) in the journal Nature Communications.

At its height in A.D. 117, the Roman Empire covered almost 2.1 million square miles (5.5 million square kilometers) around the Mediterranean Sea, occupying much of Europe, the Middle East and North Africa, the team noted in the study.

For years, the scientists have been creating a vast digital atlas called "Itiner-e" of nearly 186,000 miles (300,000 kilometers) of Roman roads. For the new study, they calculated how well Roman cities were connected to the road system.

In fact, the empire's "most important intermediary route" by land identified in the study didn't even run through Rome.

"It follows the North African and Levantine coast past Antioch and near Ankara, crosses over to Europe at Constantinople, and moves through the Po Valley and Milan into France," study co-author Tom Brughmans, a professor of classical archaeology at Aarhus University in Denmark, told Live Science in an email.

The other well-connected cities had a bevy of reasons for their numerous roads. For instance, Corinth was better connected to the road network because the roads that ran through it linked the Greek Peloponnesian Peninsula to the rest of Greece, and Ancyra was better connected because it was a vital transportation hub for Anatolia.

Rome's unique location is likely the biggest reason why it wasn’t as well connected to the road system as these other cities.

Brughmans noted that the "Italian Peninsula is an appendix to the empire's road network, and Rome is halfway down this appendix." And when "we consider all movement within the entire Italian Peninsula, we were shocked to discover that the most central road actually follows the opposite Adriatic coastline, bypassing Rome altogether," Brughmans added.

The study also found that when the shape of the land allowed it, Roman roads tended to be straight, but they were not as straight as modern-day roads.

Today, "modern road building avoids sharp turns and aims to build as straight roads as possible by strongly modifying the terrain to facilitate faster travel by car, which is made possible by modern surveying and construction methods," the team wrote in their paper.

Sea and river connections

Although the new research sheds light on road connections, it's important to remember that road travel wasn't the only means of transport in the Roman Empire. In fact, the researchers noted that Rome may have had a more significant position for sea and river transportation than it had for road transportation.

Although the study didn't look at waterways, Rome's central location in the empire meant that it would have been an important hub of water transport, the team wrote in the study.

"Rome's central location is not due to its roads, but its physical location in the centre of the Mediterranean, on the nexus of major shipping lanes," Brughmans explained.

The team said future studies should examine sea and river transport and integrate their findings with the team's Roman roads study. When considered together, road and waterway routes may help researchers better understand Roman transportation networks.

Pažout, A. et al. (2026). Network science reveals the structure and lasting impact of the Roman road system. Nature Communications, 17(9551). https://doi.org/10.1038/s41467-026-75453-3

From Augustus to Nero, see how much you know about ancient Rome's famous leaders with our Roman emperor quiz!

'> Did 'all roads lead to Rome'? New study finds other cities in the empire were better connected.

The discovery, made at the La Tejería site near the small village of El Castellar in eastern Spain, provides some of the strongest fossil evidence yet that dinosaurs could move between North America and Europe during the Late Jurassic, when the Atlantic Ocean was still in its early stages of opening after the breakup of the supercontinent Pangaea. The researchers published their findings Tuesday (Sept. 15) in the Journal of Vertebrate Paleontology.

"Paleontological studies like this one help us better understand the history of life on Earth, reconstruct ancient ecosystems, and understand how they changed through time," study first author Sergio Sánchez Fenollosa, a doctoral student who studies biodiversity and evolutionary biology at the Joint Paleontology Foundation Teruel-Dinópolis (Dinópolis Foundation), a paleontological research institution, told Live Science via email.

A sauropod in Spain

Dippy is one of the best-known dinosaurs. After its fossils made their grand debut at the Carnegie Museum of Natural History in Pittsburgh in the early 1900s, life-size fossil replicas of the towering herbivore were sent around the world, including to England, France, Spain, Argentina and Russia.

But until now, Diplodocus' Late Jurassic fossils were known only from the Morrison Formation in the western United States ‪—‬ and the latest discovery shows that Dippy wasn't a homebody.

The newly unearthed Diplodocus specimen consists of 14 well-preserved tail vertebrae and several chevrons ‪—‬ bones that helped support blood vessels and muscles within the dinosaur's tail.

Study co-author and managing director of the Dinópolis Foundation, Alberto Cobos, said it was a friend who "thought he had spotted some bones on a mountainside," Cobos told Live Science via email. "That very day, I went to the site near El Castellar (a village in the province of Teruel). Sure enough, we saw a couple of sauropod vertebral centers."

Although only part of the skeleton has been recovered, the bones show a series of characteristics associated with Diplodocus, including large cavities corresponding to where air sacs would have been, along with deep grooves running alongside the underside of the tailbones.

"It was an exciting and continuous process of seeing the pieces of the puzzle gradually fall into place," Sánchez Fenollosa said in a statement. "From the early stages of the osteological study, we noticed strong similarities with several diplodocine sauropods … With each new result, the picture became clearer: we were looking at a Diplodocus."

It's unclear which species of Diplodocus the new specimen is, but like others of its genus, it was a huge dinosaur with an extremely long neck and whip-like tail.

"The Diplodocus from El Castellar was approximately 25 meters [82 feet] long (comparable in size to its North American relatives), making it another of the giant sauropods of the Spanish Jurassic," Cobos said in the statement.

An ancient bridge

Between 195 million and 170 million years ago, the supercontinent Pangaea broke apart as the Atlantic Ocean opened. But the ocean was much narrower than it is today, and the continents were not necessarily as isolated as their modern geography is now.

Evidence indicates that temporary land bridges may have allowed some animals to move between the two regions. The most famous prehistoric land bridge is the Bering Land Bridge that humans used to move between Asia and what is now Alaska. Previous research showed the Bering Land Bridge also existed around 68 million years ago, and it may have allowed an Asian ancestor of Tyrannosaurus rex to trek into North America.

One possible route for Diplodocus into Spain may have been a land bridge that connected what is now Newfoundland with the Iberian Peninsula.

Geological conditions may have allowed dinosaurs like Diplodocus to move between continents, Sánchez Fenollosa told Live Science in an email. "This interpretation is supported not only by the fossil record but also by geological evidence," he said.

The newfound Diplodocus fossils also suggest that the distribution of giant sauropods was more complicated than the fossil record previously indicated.

"More complete specimens will be essential to understand this story in greater detail, particularly to determine which Diplodocus species inhabited Europe: whether it was one already known from North America or a previously unknown species," Sánchez Fenollosa said. "This discovery reminds us that even for such iconic dinosaurs, there are still many unanswered questions about their evolutionary history and biogeography."

'> Fossils of iconic long-necked dinosaur Diplodocus found in Europe for first time — and it may have traveled there via land bridge