The astronauts who rode Boeing's Starliner spacecraft to the International Space Station last month still don't know when they will return to Earth.

The problems are twofold. The spacecraft's reaction control thrusters overheated, and some of them shut off as Starliner approached the space station June 6. A separate, although perhaps related, problem involves helium leaks in the craft's propulsion system.

On Thursday, NASA and Boeing managers said they still plan to bring Wilmore and Williams home on the Starliner spacecraft. In the last few weeks, ground teams completed testing of a thruster on a test stand at White Sands, New Mexico. This weekend, Boeing and NASA plan to fire the spacecraft's thrusters in orbit to check their performance while docked at the space station.

The problems have led to speculation that NASA might decide to return Wilmore and Williams to Earth in a SpaceX Crew Dragon spacecraft. There's one Crew Dragon currently docked at the station, and another one is slated to launch with a fresh crew next month. Steve Stich, manager of NASA's commercial crew program, said the agency has looked at backup plans to bring the Starliner crew home on a SpaceX capsule, but the main focus is still to have the astronauts fly home aboard Starliner.

Changes by the tests' maker in recent years have shifted scores upward. That has led to hundreds of thousands of additional students getting what's considered a passing score -- 3 or above on the 1-to-5 scale -- on exams in popular courses including AP U.S. History and AP U.S. Government.

The nonprofit behind the tests, College Board, says it updated the scoring by replacing its panel of experts with a large-scale data analysis to better reflect the skills students learn in the courses. Some skeptical teachers, test-prep companies and college administrators see the recent changes as another form of grade inflation, and a way to boost the organization's business by making AP courses seem more attractive.

"It is hard to argue with the premise of AP, that students who are talented and academically accomplished can get a head start on college," said Jon Boeckenstedt, the vice provost of enrollment at Oregon State University. "But I think it's a business move." The number of students cheering their higher AP scores could rise again next year. The College Board said it is still recalibrating several other subjects, including its most popular course, AP English Language, which attracts more than half a million test takers.

For many people, the aroma of freshly brewed coffee is the start of a great day. But caffeine can cause headaches and jitters in others. That's why many people reach for a decaffeinated cup instead. I'm a chemistry professor who has taught lectures on why chemicals dissolve in some liquids but not in others. The processes of decaffeination offer great real-life examples of these chemistry concepts. Even the best decaffeination method, however, does not remove all of the caffeine -- about 7 milligrams of caffeine usually remain in an 8-ounce cup. Producers decaffeinating their coffee want to remove the caffeine while retaining all -- or at least most -- of the other chemical aroma and flavor compounds.

Decaffeination has a rich history, and now almost all coffee producers use one of three common methods. All these methods, which are also used to make decaffeinated tea, start with green, or unroasted, coffee beans that have been premoistened. Using roasted coffee beans would result in a coffee with a very different aroma and taste because the decaffeination steps would remove some flavor and odor compounds produced during roasting. Here's a summary of each method discussed by Dr. Crowder:

• The Carbon Dioxide Method: Developed in the early 1970s, the carbon dioxide method uses high-pressure CO2 to extract caffeine from moistened coffee beans, resulting in coffee that retains most of its flavor. The caffeine-laden CO2 is then filtered out using water or activated carbon, removing 96% to 98% of the caffeine with minimal CO2 residue.

• The Swiss Water Process: First used commercially in the early 1980s, the Swiss water method uses hot water and activated charcoal filters to decaffeinate coffee, preserving most of its natural flavor. This chemical-free approach removes 94% to 96% of the caffeine by soaking the beans repeatedly until the desired caffeine level is achieved.

• Solvent-Based Methods: Originating in the early 1900s, solvent-based methods use organic solvents like ethyl acetate and methylene chloride to extract caffeine from green coffee beans. These methods remove 96% to 97% of the caffeine through either direct soaking in solvent or indirect treatment of water containing caffeine, followed by steaming and roasting to ensure safety and flavor retention.

"It's chemically impossible to dissolve out only the caffeine without also dissolving out other chemical compounds in the beans, so decaffeination inevitably removes some other compounds that contribute to the aroma and flavor of your cup of coffee," writes Dr. Crowder in closing. "But some techniques, like the Swiss water process and the indirect solvent method, have steps that may reintroduce some of these extracted compounds. These approaches probably can't return all the extra compounds back to the beans, but they may add some of the flavor compounds back."

Somehow, this two and a half minute skit perfectly captures the essence of the entire series.

Shamelessly posted based on a comment in another post from @Heikki@lemm.ee

The FTC has sent mandatory notices for information to eight companies it says engages in "surveillance pricing", the process by which prices are rapidly changed using AI based on data about customer behavior and characteristics. This process, the FTC claims, allows companies to charge different customers different prices for the same product.

The list includes Mastercard, JPMorgan Chase, Accenture and consulting giant McKinsey. It also includes software firm Task, which counts McDonald's and Starbucks as clients; Revionics, which works with Home Depot, Tractor Supply and grocery chain Hannaford; Bloomreach, which services FreshDirect, Total Wine and Puma; and Pros, which was named Microsoft's internet service vendor of the year this year. "Firms that harvest Americans' personal data can put people's privacy at risk," FTC Chair Lina Khan said in a news release. "Now firms could be exploiting this vast trove of personal information to charge people higher prices."

Top: Captain Picard and Kamala in The Perfect Mate

Bottom: Professor X and Jean Grey in X-Men: The Last Stand

Had no idea Patrick Stewart and Famke Janssen had collaborated prior to X-Men.

Phoebus 2A, the most powerful space nuclear reactor ever made, was fired up at Nevada Test Site on June 26, 1968. The test lasted 750 seconds and confirmed it could carry first humans to Mars. But Phoebus 2A did not take anyone to Mars. It was too large, it cost too much, and it didn’t mesh with Nixon’s idea that we had no business going anywhere further than low-Earth orbit.

But it wasn’t NASA that first called for rockets with nuclear engines. It was the military that wanted to use them for intercontinental ballistic missiles. And now, the military wants them again.

A solar superstorm in May caused thousands of satellites to simultaneously maneuver to maintain altitude due to the thickening of the upper atmosphere, creating potential collision hazards as existing prediction systems struggled to cope. Space.com reports:

According to a pre-print paper published on the online repository arXiv on June 12, satellites and space debris objects in low Earth orbit -- the region of space up to an altitude of 1,200 miles (2,000 kilometers) -- were sinking toward the planet at the speed of 590 feet (180 meters) per day during the four-day storm. To make up for the loss of altitude, thousands of spacecraft began firing their thrusters at the same time to climb back up. That mass movement, the authors of the paper point out, could have led to dangerous situations because collision avoidance systems didn't have time to calculate the satellites' changing paths.

The solar storm that battered Earth from May 7 to 10 reached the intensity of G5, the highest level on the five-step scale used by the National Oceanic and Atmospheric Administration (NOAA) to assess the strength of solar storms. It was the strongest solar storm to hit Earth since 2003. The authors of the paper, however, pointed out that the environment around the planet has changed profoundly since that time. While only a few hundred satellites were orbiting Earth twenty years ago, there are thousands today. The authors of the paper put the number of "active payloads at [low Earth orbit]" at 10,000. [...] The new paper points out that space weather forecasts ahead of the May storm failed to accurately predict the duration and intensity of the event, making satellite collision predictions nearly impossible.

On the upside, the storm helped to clear out some junk as defunct satellites and debris fragments spiraled deeper into the atmosphere. The authors of the report estimate that thousands of space debris objects lost several kilometers in altitude during the storm. More powerful solar storms can be expected in the coming months as the peak of the current solar cycle -- the 11-year ebb and flow in the number of sunspots, solar flares and eruptions -- is expected in late 2024 and early 2025.

The paper can be found here.