page_title: 142 Polana
hierarchical_section_title: 142 Polana
caption_attribution_description: The orbit of 142 Polana compared to Mars and Jupiter. This asteroid is in a 1:2 resonance with Mars.
context_page_description: Polana is a very dark asteroid from the asteroid belt. It was discovered by Johann Palisa on January 28, 1875, and named after the city of Pola, home of the Austrian Naval Observatory where he made the discovery.
  It is a major member of the eponymously named Polana family, which is a subgroup of the Nysa family. The asteroid has an estimated diameter of about 55.3 km and a low albedo of 0.045. It is orbiting at a distance of 2.419 times the separation of the Earth from the Sun, with an orbital period of 3.76 years and an eccentricity of 0.14.
  In the Tholen classification scheme, Polana is a primitive carbonaceous asteroid of type F, which is a subdivision of more common C-type. Under the SMASS classification taxonomy, Polana is listed as a B-type asteroid; a group that combines both the Tholen B and F types. The spectrum of this object suggests the presence of magnetite, which gives it the spectrally blue coloration that is a characteristic of this SMASS class.
context_section_description: Polana (minor planet designation: 142 Polana) is a very dark asteroid from the asteroid belt. It was discovered by Johann Palisa on January 28, 1875, and named after the city of Pola (now Pula, Croatia), home of the Austrian Naval Observatory where he made the discovery.
  It is a major member of the eponymously named Polana family, which is a subgroup of the Nysa family. The asteroid has an estimated diameter of about 55.3 km and a low albedo of 0.045. It is  orbiting at a distance of 2.419 times the separation of the Earth from the Sun, with an orbital period of 3.76 years and an eccentricity of 0.14.
  In the Tholen classification scheme, Polana is a primitive carbonaceous asteroid of type F, which is a subdivision of more common C-type. Under the SMASS classification taxonomy, Polana is listed as a B-type asteroid; a group that combines both the Tholen B and F types. The spectrum of this object suggests the presence of magnetite (Fe₃O₄), which gives it the spectrally blue coloration that is a characteristic of this SMASS class.
caption: Polana is in a 1:2 resonance with Mars