unicorns
As far as we know, Haumea does not have an atmosphere, though future advances in telescopes or probes may yet provide a definitive answer.
rock and gas because...
Haumea is sometimes known by its minor-planet designation, 136108 Haumea.
To the best of our knowledge, no satellites or robots have directly explored the planet Haumea. Haumea is a dwarf planet located in the Kuiper Belt beyond Neptune, and its distance from Earth makes it challenging to send a mission there. Most of our knowledge about Haumea comes from observations made by telescopes on Earth.
Haumea's rotational period is 3.9155 hours.
Hi`iaka and Namaka, two of the daughters of Haumea
No. Haumea is not classified as a planet. It is a dwarf planet.
Yes, Haumea is a rocky, terrestrial planet.
A day on Haumea is very short compared to here on Earth. Haumea's rotational period is just 3.9155 hours.
Haumea's orbital period is 283 or 103,468 days
At this time it is believed tha Haumea has no atmosphere.