A newly discovered dwarf-planet candidate beyond Pluto takes roughly 25,000 years to orbit the Sun and is detectable for only about 0.5% of that journey — making its chance discovery in archival images evidence that hundreds of similar worlds may remA newly discovered dwarf-planet candidate beyond Pluto takes roughly 25,000 years to orbit the Sun and is detectable for only about 0.5% of that journey — making its chance discovery in archival images evidence that hundreds of similar worlds may remain h Space Daily