Solar Granulation


A successful attempt to image Solar granulation with an amateur 280mm Schmidt-Cassegrain telescope located in Central Europe.

M 51

Ultra-deep view of the Whirlpool Galaxy—a collaboration project initiated by Yuri Toropin.

Melotte 15


Melotte 15

Melotte 15 is a very young star cluster in the IC 1805 nebula, also known as the Heart Nebula. It consists of massive OB stars with a mean age of only 1.5 million years. Melotte 15 is one of the core clusters of the Cas OB6 stellar association.

Ultra-Luminous X-ray Sources: an Overview of Discussion on Their Origins and Nature

The subject of the nature and origins of ultra-luminous X-ray sources (ULXs) remains at the frontier of modern research. Existing data allows to fit a wide range of interpretations, including those based on stellar-mass black holes (sMBHs) and intermediate-mass black holes (IMBHs), accretion-powered pulsars, microquasars, and so on. The research of the ULXs is of cosmological and astrophysical importance, as they may become evidence of the existence of IMBHs that may be intimately connected to the formation of first active galactic nuclei engines at z~6.4. Although more recent research favors ULX interpretation based on stellar origins, the presence of IMBHs cannot be ruled out completely. In particular, hyper-luminous X-ray sources (HLXs), which comprise the brightest subset of the ULXs with X-ray luminosities LX 1041 erg s−1, are considered to be the strongest cases for harboring black holes of that type. This report will overview some of the observations and general properties of ULXs and will serve as an introduction to the discussion on the underlying physical models. In addition to ULX models based on black holes of both types, alternative interpretations will be reviewed. Within the sMBH framework, in particular, the importance of interpreting short timescale variations of ULXs is emphasized as a good diagnostic for revealing the underlying super-Eddington emission mechanisms.

Essay: Ultra-Luminous X-ray Sources: an Overview of Discussion on Their Origins and Nature

Detection of Population III Stars

It is suggested that two distinct Population III classes may have existed: population III.1 and population III.2. The former, consisting of stars of ∼ 100M⊙, and possibly going as high as 500M⊙, is believed to be formed in dark matter halos at z ≈ 10–30 which corresponds to the times of 0.1–0.48 Gyr after the Big Bang (Rydberg et al. 2013).

Note: Detection of Population III Stars

Galaxy Photometry


The aims of this project are as following:

  1. Reduce multi-band (BVR) CCD data of the M 51, M 63, M 106 (NGC 4258) and NGC 4725 galaxies obtained via 0.8-m (30-inch) telescope at the McDonald Observatory (MDO) in Austin, TX.
  2. Prepare scientific and color-combined frames.
  3. Discuss differences and similarities of galactic features appearing in the images that depend on the wavelength and the galaxy type.
  4. Conduct preliminary surface photometry of galaxies.

Project Report: Galaxy Photometry