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The purpose of this paper consists in constructing the near-equilibrium model of the dwarf planet Haumea and developing the latent mechanism of accumulation of icy masses at sharp ends of the rapidly rotating planet. The model can be introduced by combining the ellipsoidal stone core with confocal icy shell and represents a non-uniform figure of rotating gravitating mass with superficial tension from the icy layer. We thoroughly study its dynamic properties and achieve that the gravitational potential on an external and intermediate (between the core and the mantle) surfaces was square-law function from coordinates. Using the new rigorous method we found that the thickness of an ice shell is equal to $h \approx 30\mbox{ km}$ , and its mass makes only 6.6 % from mass of a stone core. In absence of coherence between two surfaces of level, there is a growth of stresses and restructuring the core and the shell. It is found that the difference between angular velocities on both surfaces doesn’t exceed 6 %, which activates a special mechanism of relaxation. The relaxation may lead to considerable (up to 10 %) lengthening the equatorial size of the body. This restructuring the shell leads to accumulation of icy masses at the sharp ends of the planet, which then separate from Haumea. For formation of two satellites of the planet Haumea it has been spent only 8 % from the mass of a shell. Before separation of satellites the planet Haumea was in near-equilibrium state, and its angular momentum was at 1.13 more, and the period of rotation was $16^{m}$ shorter and made $T \approx 3.64\mbox{ h}$ . The mechanism predicts that the orbits of satellites can not deviate much from the equatorial plane of Haumea. This is consistent with observations: indeed, the orbit of Namaka is almost in the equatorial plane, and the orbit of massive Hi’iaka deviates only on 13°. The new mechanism can be useful also for studying the evolution of other ice-cover planets and satellites.

Observations of the distant dwarf planet Haumea constrain its size, shape and density, and reveal an encircling planetary ring. The discovery suggests that rings are not as rare in the Solar System as previously thought. See Letter p.219 Haumea is a dwarf planet beyond the orbit of Neptune. It is rapidly rotating and very elongated, unlike the other three known trans-Neptunian dwarf planets. Jose Ortiz and collaborators obtained observations from multiple Earth-based telescopes as Haumea passed in front of a background star. This occultation enabled the team to constrain the density of Haumea to an upper limit of about 1,885 kilograms per cubic metre. They also constrained its ellipsoid shape and albedo (0.51). They did not detect an atmosphere around the planet, but found a ring circling it. They determined that the ring is 70 kilometres wide, has a radius of about 2,287 kilometres and lies in the same orbital plane as Haumea's equator and largest moon. It has an orbital period that is three times the spin period of Haumea. The ring absorbed roughly half of the star light coming through, giving it an opacity of 0.5.