WASHINGTON (AP) — Astronomers say Pluto's icy more distant sister seems even more alien than thought because it doesn't have an atmosphere.

Scientists gained that bit of new knowledge about the dwarf planet Makemake (MAH'-kay MAH'-kay) by measuring light from data gathered by several large telescopes. Researchers report in the journal Nature that the small planet may simply have some pockets of atmosphere from methane ice turning into gas.

Makemake is one of four dwarf planets in our solar system beyond Neptune. It is so far from the sun its temperature is about 400 degrees below zero. Scientists compare it to getting warmth from a 100-watt light bulb 33 feet away. It was discovered in 2005.