Marcel Drechsler

Deep optical emission-line images are presented for nine known plus three new Galactic supernova remnants (SNRs), all but one having at least one angular dimension >1°. Wide-field images taken in H α and [O iii ] λ 5007 reveal many new and surprising remnant structures including large remnant shock extensions and “breakout” features not seen in pub...

We report the serendipitous discovery of a 8 ′ × 12 ′ emission shell brightest in [O iii ] centered on the X-ray binary B[e] star, CI Cameleopardalis (CI Cam). This shell, detected during a survey of optical emission associated with the Galactic supernova remnant G150.3+4.5, is seen outside but immediately adjacent to the remnant’s optical filament...

Drechsler et al. reported the unexpected discovery of a 1.°5 long [O iii ] emission nebula 1.°2 southeast of the M31 nucleus. Here we present additional images of this large emission arc, called the Strottner–Drechsler–Sainty Object (SDSO), along with radial velocity and flux measurements from low-dispersion spectra. Independent sets of [O iii ] im...

Aims. Our goal is to study the long-term mass-loss rate characteristics of asymptotic giant branch (AGB) stars through wind-wind and wind-interstellar medium interaction. Methods. Far-ultraviolet (FUV) images from the GALEX survey are used to investigate extended UV emission associated with AGB stars. Results. FUV emission was found towards eight o...

Drechsler et al. (2023) reported the unexpected discovery of a 1.5 degree long [O III] emission nebula 1.2 degrees southeast of the M31 nucleus. Here we present additional images of this large emission structure, called SDSO, along with radial velocity and flux measurements from low-dispersion spectra. Independent sets of [O III] images show SDSO t...

We report the discovery of a broad, 1.°5 long filamentary [O iii ] emission nebulosity some 1.°2 southeast of the M31 nucleus. This nebulosity is not detected in H α and has no obvious emission counterparts in X-ray, UV, optical, infrared, and radio surveys. To our knowledge, this emission feature has not been previously reported in the literature....

We present the key results from an intensive and coordinated ten-year amateur observational programme designed to uncover and confirm Galactic planetary nebulae (PNe). This was undertaken and led by a dedicated group of largely French amateur astronomers in collaboration with professional colleagues. Over this period this group has uncovered a tota...

Galactic supernova remnants (SNRs) with angular dimensions greater than a few degrees are relatively rare, as are remnants located more than 10° off the Galactic plane. Here we report a UV and optical investigation of two previously suspected SNRs more than 10° in both angular diameter and Galactic latitude. One is a proposed remnant discovered in...

Context. During a search for previously unknown Galactic emission nebulae, we discovered a faint 36′ diameter H α emission nebula centered around the periodic variable YY Hya. Although this star has been classified as an RR-Lyr variable, such a classification is inconsistent with a Gaia distance of ≃450 pc. The GALEX image data also show YY Hya as...

During a search for previously unknown Galactic emission nebulae, we discovered a faint 36' diameter Halpha emission nebula centered around the periodic variable YY Hya. Although this star has been classified as RR-Lyr variable, such a classification is inconsistent Gaia distance of ~450 pc. GALEX image data also shows YY Hya to have a strong UV ex...

Galactic supernova remnants (SNRs) with angular dimensions greater than a few degrees are relatively rare, as are remnants located more than ten degrees off the Galactic plane. Here we report the results of a UV and optical investigation of two previously suspected SNRs that are more than ~10 degrees in both angular diameter and Galactic latitude....

Wide-field Hα images of the Galactic plane have revealed a new supernova remnant (SNR) nearly three degrees in diameter centred at l = 107.0, b = +9.0. Deep and higher resolution Hα and [O III] 5007 Å images show dozens of Hα filaments along the remnant’s northern, western, and southwestern limbs, but few [O III] bright filaments. The nebula is wel...

Wide-field H-alpha images of the Galactic plane have revealed a new supernova remnant (SNR) nearly three degrees in diameter centred at l = 107.0, b = +9.0. Deep and higher resolution H-alpha and [O III] 5007 Ang images show dozens of H-alpha filaments along the remnant's northern, western, and southwestern limbs, but few [O III] bright filaments....