In today’s Bulldog wrapup of science and technology news:

  • UK: Attacker used WhatsApp, firm must help police get access
  • Apple: Software flaws in latest WikiLeaks docs are all fixed
  • German scientists test ‘artificial sun’
  • Spacewalking astronauts prep station for new parking spot

The details:

  • UK: Attacker used WhatsApp, firm must help police get access

Westminster Bridge attacker Khalid Masood sent a WhatsApp message that cannot be accessed because it was encrypted by the popular messaging service, a top British security official said Sunday.

British press reports suggest Masood used the messaging service owned by Facebook just minutes before the Wednesday rampage that left three pedestrians and one police officer dead and dozens more wounded.

As controversy swirled over the encrypted messages, police made another arrest in Birmingham, England, where Masood had lived. The 30-year-old is one of two men now in custody over possible links to the attack. Neither has been charged or publicly named.

Masood was shot dead on the grounds of Parliament.

Home Secretary Amber Rudd used appearances on BBC and Sky News to urge WhatsApp and other encrypted services to make their platforms accessible to intelligence services and police trying to carrying out lawful eavesdropping.

“We need to make sure that organizations like WhatsApp — and there are plenty of others like that — don’t provide a secret place for terrorists to communicate with each other,” she said.

Rudd did not provide any details about Masood’s use of WhatsApp, saying only “this terrorist sent a WhatsApp message and it can’t be accessed.”

  • Apple: Software flaws in latest WikiLeaks docs are all fixed

Apple said purported hacking vulnerabilities disclosed by WikiLeaks this week have all been fixed in recent iPhones and Mac computers.

The documents released by the anti-secrecy site Thursday morning pointed to an apparent CIA program to hack Apple devices using techniques that users couldn’t disable by resetting their devices.

The iPhone hack was limited to the 3G model from 2008. In a statement late Thursday, Apple said the flaw was fixed with the release of the iPhone 3GS a year later. Apple also said the Mac vulnerabilities were all fixed in all Macs launched after 2013.

Apple’s statement was consistent with assessments from security experts, who say that many of the apparent vulnerabilities were in older technology. Apple is going further in saying those flaws have all been fixed, based on its preliminary analysis.

Security experts say the exploits described in the WikiLeaks documents are plausible, but suggest they pose little threat to typical users. Besides being likely out of date, the techniques also typically require physical access to devices, something the CIA would use only for targeted individuals, not a broader population.

The CIA has not commented on the authenticity of this and earlier WikiLeaks revelations, but has previously said it complies with a legal prohibition against electronic surveillance “targeting individuals here at home, including our fellow Americans.”

  • German scientists test ‘artificial sun’

Scientists in Germany flipped the switch Thursday on what’s being described as “the world’s largest artificial sun,” a device they hope will help shed light on new ways of making climate-friendly fuels.

The giant honeycomb-like setup of 149 spotlights — officially known as “Synlight” — in Juelich, about 30 kilometers (19 miles) west of Cologne, uses xenon short-arc lamps normally found in cinemas to simulate natural sunlight that’s often in short supply in Germany at this time of year.

By focusing the entire array on a single 20-by-20 centimeter (8×8 inch) spot, scientists from the German Aerospace Center, or DLR , will be able to produce the equivalent of 10,000 times the amount of solar radiation that would normally shine on the same surface.

Creating such furnace-like conditions — with temperatures of up to 3,000 degrees Celsius (5,432 Fahrenheit) — is key to testing novel ways of making hydrogen, according to Bernhard Hoffschmidt, the director of DLR’s Institute for Solar Research.

Many consider hydrogen to be the fuel of the future because it produces no carbon emissions when burned, meaning it doesn’t add to global warming. But while hydrogen is the most common element in the universe it is rare on Earth. One way to manufacture it is to split water into its two components — the other being oxygen — using electricity in a process called electrolysis.

Researchers hope to bypass the electricity stage by tapping into the enormous amount of energy that reaches Earth in the form of light from the sun.

  • Spacewalking astronauts prep station for new parking spot

Spacewalking astronauts prepped the International Space Station on Friday for a new parking spot reserved for commercial crew capsules.

The 250-mile-high complex already has one docking port in place for the SpaceX Crew Dragon and Boeing Starliner, which should start carrying up astronauts as early as next year. Friday’s spacewalk set the stage for a second docking location. A new docking device will fly up late this year or early next.

[VIDEO: Watch a recap of the latest effort at https://www.youtube.com/watch?v=mTc22ZPMl_c ]

NASA astronaut Shane Kimbrough disconnected all four cables from an old docking port, using some extra force on one. He looped a spare tether around the balky cable and pulled, and off it came. “Nicely done, Shane,” Mission Control radioed.

On Sunday, flight controllers in Houston will move the old port to provide better clearance for the future ships. Then on Thursday, the crew will conduct another spacewalk to secure the unit.

Until the new crew capsules come on line, U.S. astronauts will keep riding Russian rockets to orbit.

As Kimbrough worked on the docking port and replaced a computer-relay box, French astronaut Thomas Pesquet hunted for signs of an ammonia coolant leak in outdoor plumbing. The leak, while still small, has worsened recently, and NASA wants to pinpoint the location.

“No leaks. No flakes whatsoever,” he reported.