Notice: Function _load_textdomain_just_in_time was called incorrectly. Translation loading for the polylang domain was triggered too early. This is usually an indicator for some code in the plugin or theme running too early. Translations should be loaded at the init action or later. Please see Debugging in WordPress for more information. (This message was added in version 6.7.0.) in /var/webs/wwwhelmos2/www/wp-includes/functions.php on line 6114
Δημοσιεύσεις – Page 2 – Αστεροσκοπείο Χελμού

Δημοσιεύσεις

Δημοσιεύσεις2023-07-31T14:19:06+03:00

Πρόσφατες Δημοσιεύσεις

Deep optical study of the mixed-morphology supernova remnant G 132.7+1.3 (HB3)

17/02/2022|

We present optical ccd images of the large supernova remnant (SNR) G132.7 + 1.3 (HB3) covering its full extent for the first time, in the emission lines of H α+ [N II], [S II] and [O III], where new and known filamentary and diffuse structures are detected. These observations are supplemented by new low-resolution long-slit spectra and higher-resolution images in the same emission lines. Both the flux-calibrated images and spectra confirm that the optical emission originates from shock-heated gas since the [S II]/H α > 0.4.

Constraints on the structure and seasonal variations of Triton’s atmosphere from the 5 October 2017 stellar occultation and previous observations

27/01/2022|

A stellar occultation by Neptune's main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection. We aimed at constraining Triton's atmospheric structure and the seasonal variations of its atmospheric pressure since the Voyager 2 epoch (1989). We also derived the shape of the lower atmosphere from central flash analysis.

First deep images catalogue of extended IPHAS PNe

31/08/2021|

A significative fraction of all massive stars in the Milky Way move supersonically through their local interstellar medium (ISM), producing bow shock nebulae by wind-ISM interaction. The stability of these observed astrospheres around cool massive stars challenges precedent two-dimensional (magneto-)hydrodynamical simulations of their surroundings. We present three-dimensional magneto-hydrodynamical (3D MHD) simulations of the circumstellar medium of runaway M-type red supergiant stars moving with velocity v* = 50 km s−1 . We treat the stellar wind with ...

3D MHD astrospheres: applications to IRC-10414 and Betelgeuse

12/07/2021|

A significative fraction of all massive stars in the Milky Way move supersonically through their local interstellar medium (ISM), producing bow shock nebulae by wind-ISM interaction. The stability of these observed astrospheres around cool massive stars challenges precedent two-dimensional (magneto-)hydrodynamical simulations of their surroundings. We present three-dimensional magneto-hydrodynamical (3D MHD) simulations of the circumstellar medium of runaway M-type red supergiant stars moving with velocity v* = 50 km s−1 . We treat the stellar wind with ...

Edge-on boxes with X-features as parts of galactic bars – NGC 352: A direct piece of observational evidence

01/03/2021|

This paper is a contribution to the discussion about whether the X/peanut component is part of the bar, or the bar itself. Our goal is to present a clear-cut case of a barred-spiral galaxy in which all structural components (i.e. the thick and thin part of the bar and the spiral arms) can be observed in its image and their dimensions directly measured there. We obtained deep images of the nearby galaxy NGC 352, which has an ideal inclination allowing us to observe all of the parts that compose its morphology, estimate their relative sizes, and determine the topology of the luminous matter...

Ανακαλύψτε το Σύμπαν

Go to Top