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Abstract. A survey of Class II methanol masers at 6.7 GHz was made in the Northern hemisphere with the 32-m Medicina radio telescope. 42 objects were detected, 20 of them are new detections at 6.7 GHz. Our results show that the detection rate of 6.7 GHz masers toward the inner part of the Galaxy is higher than in other directions. It is confirmed that most of the methanol masers are associated with faint compact HII regions. The 6.7 GHz methanol masers show large velocity dispersion and large velocity offset from the velocity of parent molecular clouds.

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The Russian Academy of Sciences and Federal Space Agency, together with the participation of many international organizations, worked toward the launch of the RadioAstron orbiting space observatory with its onboard 10-m reflector radio telescope from the Baikonur cosmodrome on July 18, 2011. Together with some of the largest ground-based radio telescopes and a set of stations for tracking, collecting, and reducing the data obtained, this space radio telescope forms a multi-antenna groundspace radio interferometer with extremely long baselines, making it possible for the first time to study various objects in the Universe with angular resolutions a million times better than is possible with the human eye. The project is targeted at systematic studies of compact radio-emitting sources and their dynamics. Objects to be studied include supermassive black holes, accretion disks, and relativistic jets in active galactic nuclei, stellar-mass black holes, neutron stars and hypothetical quark stars, regions of formation of stars and planetary systems in our and other galaxies, interplanetary and interstellar plasma, and the gravitational field of the Earth. The results of ground-based and inflight tests of the space radio telescope carried out in both autonomous and ground-space interferometric regimes are reported. The derived characteristics are in agreement with the main requirements of the project. The astrophysical science program has begun.

Eight class I methanol masers [DR21(OH), DR21W, OMC-2, NGC 2264, M8E, NGC 6334I(N), L379, W33Met] in the transition at 44069 MHz were imaged with angular resolution with the 7 0 È6 1 A`D0A .2 The images show a di †erent distribution of maser "" spots ÏÏ from a simple structure of one or two VLA.2 spots at NGC 2264, M8E, DR21W, to a very complex structure of many spots at DR21(OH) (17 spots), OMC-2 (8 spots), NGC 6364I(N) (23 spots), L379 (11 spots), and W33Met (5 spots). Some spots are partially resolved, but the majority of them are still unresolved. The maximum brightness temperatures of the methanol (44,069 MHz) emission features at the observed sources ranges from 1.9 ] 106 to 3.6 ] 108 K. The velocity range varies from the minimum 0.8 km s~1 at NGC 2264 to the maximum 6.9 km s~1 at DR21(OH).