NASA's deep-space robots are engineering wonders. Voyager probes are still operational decades after launch. Parker Solar Probe's heat shield will keep it running for years.
Lucy, despite its problems, will visit a few space rocks during the next 12 years.
DART won't advance solar system research for decades. The November 2021 spacecraft will be gone this week.
DART is NASA's test of a planetary defence system that smashes spaceships into approaching asteroids.
Asteroids the size of refrigerators and cars often hit Earth. Most of the rock burns up in Earth's atmosphere, making them harmless. 66 million years ago,
a gigantic space asteroid named Chicxulub killed off dinosaurs.