Hail the size of grapefruit shattered car windows in Johnson City, Texas. In June, 2024, a storm chaser found a hailstone almost as big as a pineapple. Even larger hailstones have been documented in South Dakota, Kansas and Nebraska. Hail has damaged airplanes and even crashed through the roofs of houses. Hail begins as tiny crystals of ice that are swept into a thunderstorm's updraft. As these ice embryos collide with supercooled water ' liquid water that has a temperature below freezing ' the water freezes around each embryo, causing the embryo to grow. Supercooled water freezes at different rates, depending on the temperature of the hailstone surface, leaving layers of clear or cloudy ice as the hailstone moves around inside a thunderstorm. If you cut open a large hailstone, you can see those layers, similar to tree rings. Rotating, long-lived, severe thunderstorms called supercells tend to produce the largest hail. In supercells, hailstones can be suspended for 10-15 minutes or more in strong thunderstorm updrafts, where there is ample supercooled water, before falling out of the storm due to their weight or moving out of the updraft....

Since President Donald Trump excitedly announced that he would be accepting a US$400 million plane from the Qatari government to serve as the next Air Force One, even members of his own party have expressed alarm. There's the price tag of refurbishing the plane with top-secret systems ' upward of $1 billion, according to some estimates. Then there are the conflicts of interest from accepting such a large present from a foreign nation ' what some say would be the most valuable gift ever given to the U.S. Franklin D. Roosevelt became the first president to fly while in office. In January 1943, he boarded the Navy-owned, civilian-operated Boeing Dixie Clipper ' a sea plane ' for a trip to Casablanca to meet with Allied leaders. The security measures needed to safely transport the president ' especially during wartime ' spurred the creation of the first custom-built aircraft for presidential use, a heavily modified VC-54 Skymaster. Though officially named 'The Flying White House,' the new presidential aircraft became better known by its nickname, the 'Sacred Cow.'...

Hamad International Airport, in Qatar's capital, is sometimes home to the $400 million 'palace in the sky,' a luxury liner that Trump is eyeing. Qatar's royal family plans to give the plane to Trump as a temporary replacement for the aging Air Force One and then to his future presidential library after he leaves office. The Qatari aircraft was in Texas, not Doha, during the tarmac welcome ceremony that Trump received on the second stop of his Middle East trip. But questions about the gift's security and ethics have shadowed the entire week. Trump has privately defended accepting the Qatari plane as a replacement for the current Air Force One, which dates to 1990. He has told aides and advisers that it is 'humiliating' for the president of the United States to fly in an outdated plane and that foreign leaders will laugh at him if he shows up at summits in the older aircraft, a White House official and an outside adviser told us, granted anonymity to discuss private conversations. The outside adviser said that Trump has also mused about continuing to use the Qatari plane after he departs the White House....

Twice in the past five months, the company launched a hypersonic vehicle over the Pacific Ocean, accelerated it to more than five times the speed of sound, and autonomously landed at Vandenberg Space Force Base in California. Stratolaunch used the same vehicle for both flights. This is the first time anyone in the United States has flown a reusable hypersonic rocket plane since the last flight of the X-15, the iconic rocket-powered aircraft that pushed the envelope of high-altitude, high-speed flight 60 years ago. Stratolaunch announced the results of its two most recent test flights Monday. In December and again in March, Stratolaunch's Talon-A2 rocket plane launched from the belly of an enormous carrier aircraft over the Pacific Ocean and flew several hundred miles to Vandenberg, a military spaceport about 140 miles northwest of Los Angeles. There, the aircraft touched down on a concrete runway that NASA and the Air Force once considered for Space Shuttle landings. Zachary Krevor, president and CEO of Stratolaunch, spoke with Ars on Monday afternoon. He said the Talon test vehicle advances the capability lost with the retirement of the X-15 by flying autonomously. Like the Talon-A, the X-15 released from a carrier jet and ignited a rocket engine to soar into the uppermost layers of the atmosphere. But the X-15 had a pilot in command, while the Talon-A flies on autopilot....