The New Horizons mission currently flying through the Kuiper Belt could be facing an unexpected change of plans. NASA's Science Mission Directorate is soliciting input on turning the spacecraft into a heliospheric science probe. The agency wants to do it much sooner than mission planners intended. If that happens, it will stop further planned planetary exploration of objects in that distant regime of the solar system.

The changes NASA proposes come as a surprise since the spacecraft continues to perform Kuiper Belt object observations. And, it has received a very good recent senior science review. That report stated, "This is likely the only spacecraft humans will send through the outer solar system for at least 20–30 years.

Extreme cold is merciless on machinery. Fluids thicken to useless goo. Rubber seals stiffen and crack.

The problems pile up as the temperature falls. Metal becomes brittle, and wires contract. Batteries stop working, adhesives stop sticking and LCD screens go black as their liquid crystal freezes solid.

And that's just here on Earth.

When NASA's new lunar rover lands on the moon's south pole next year, it will encounter a whole new kind of cold.

Temperatures there hover around minus 280 degrees Fahrenheit (minus 173 degrees Celsius). In the permanent shadows of polar craters, it can fall to minus 388 F (minus 233 C).

For context, Antarctica's Vostok Station holds the record for the lowest temperature ever recorded on this planet: minus 128.6 F (minus 89.2 C), recorded July 21, 1983. A typical day on the moon is about 150 degrees colder than the coldest it has ever been on Earth.

Previous rovers for the moon and Mars—which is also cold, averaging minus 80 F—have been equipped with built-in heaters that switch on at the start of the lunar or Martian day and take several hours to warm enough for the machines to begin their daily tasks.

SpaceX on Monday postponed the first test flight of Starship, the most powerful rocket ever built, designed to send astronauts to the Moon and Mars and beyond.

Liftoff of the giant rocket was called off just minutes ahead of the scheduled launch time because of a pressurization issue in the booster stage, SpaceX officials said.

SpaceX said the launch will be delayed for at least 48 hours.

Starship had been scheduled to blast off at 8:20 am Central Time (1320 GMT) from Starbase, the SpaceX spaceport in Boca Chica, Texas.

The US space agency NASA has picked the Starship spacecraft to ferry astronauts to the Moon in late 2025—a mission known as Artemis III—for the first time since the Apollo program ended in 1972.

A frozen valve forced a postponement on Monday of the first test flight of SpaceX's Starship, the most powerful rocket ever built, designed to send astronauts to the Moon, Mars and beyond.

Liftoff of the gigantic rocket was called off less than 10 minutes ahead of the scheduled launch because of a pressurization issue in the first-stage booster, SpaceX said.

The private space company continued with the countdown in what it called a "wet dress rehearsal," stopping the clock with 10 seconds to go, just before the massive engines on the booster were to have been ignited.

SpaceX founder Elon Musk said a frozen pressure valve forced a scrub of the launch, which had been planned for 8:20 am Central Time (1320 GMT) from Starbase, the SpaceX spaceport in Boca Chica, Texas.