Аннотация
This study presents new evidence supporting the periodic occurrence of sublimation-driven activity on the main-belt asteroid (704) Interamnia, initially detected near perihelion in 2012.New low-resolution R ≈ 600 reflectance spectra of Interamnia were obtained on 10 February 2025 at the Assy-Turgen Observatory using the 1.5-meter AZT-20 telescope, covering the 3500-7500 Å spectral range.At the time of observation, the asteroid's heliocentric distance was approximately 3.499 AU, placing it near aphelion (≈ 3.53 AU).The spectra reveal a broad absorption feature centered around 0.45-0.50µm and an overall negative spectral slope.The observed spectrum was compared with averaged data from the SMASSII and Gaia DR3 surveys.Taxonomic classification using a template-matching approach identifies the asteroid as belonging to the F-type group, with weak spectral indications of sublimation activity.A comparison with modeled spectra of carbonaceous chondrite analogs suggests a composition dominated by CM and CI chondrites, which are rich in volatiles and hydrated minerals.These findings indicate that Interamnia is a dark, carbonaceous body with a primitive composition.The presence of transient sublimation activity, along with its low albedo and thermal properties, supports the hypothesis that (704) Interamnia is a large, partially degassed primitive object.Continued spectroscopic monitoring will be essential to further constrain the nature and extent of its activity.