gjdonatiello
Ultra-deep imaging of M33: exploring its stellar halo
Ultra-deep imaging of M33: exploring its stellar halo
Credit: Giuseppe Donatiello
Triangulum Galaxy Extended Halo - And450 survey (sample)
by Giuseppe Donatiello flic.kr/p/2q7MZSG
Triangulum Galaxy (M33) extends well beyond its disk in a radius of some degrees. In this region, excluding the dust cirrus clouds, there is a system of faint stellar streams and debris produced by the tidal destruction of dwarf galaxies.
Such structures are extremely weak, but they can be highlighted with an appropriate treatment of the data (it is not a simple "inverted") that enhances the latent signal.
(J2000) RA: 01h 33m 50.02s Dec: +30° 39′ 36.7″
Messier 33 is a low-luminosity flocculent spiral galaxy at 3 million light-years in Triangulum. It is catalogued also as NGC 598 and known as Triangulum Galaxy. The galaxy is the smallest spiral galaxy in the Local Group and it is believed to be a big satellite of the Andromeda Galaxy.
M33 has two asymmetric faint arms, and an interstellar medium rich in gaseous filaments that extends for about 7 kpc. Although the inner disk is relatively undisturbed, the northern arm is less regular in shape than the southern one. M33, is a bulge-free galaxy with only two optically luminous dwarf galaxies believed to be its satellites: AndXXII (McConnachie et al., 2009; Martin et al., 2016) and Pisces VII (Martínez-Delgado et al., 2022) m discovered by me in 2020. However, given its mass, ΛCDM cosmological simulations predict that M33 should host a larger number of satellites, at least 10.
The neutral hydrogen (HI) disk is three times larger than the star-forming disk and is clearly warped. The outer disk has the same inclination as the inner one with respect to our line of sight but the position angle of the major axis changes by about 30 degrees compared to the inner disk and is more aligned with the M31 direction. While M33's undisturbed inner disk indicates that no major collisions between M31 and M33 or between M33 and a satellite have occurred in the past, the distortion could be the result of a flyby about 9 billion years ago. Timing assessments make this scenario unlikely and favor the hypothesis of a first fall of M33 in the region of influence of M31.
The image is a panel from my And450 photo survey that I have been doing for a few years.
The nomenclature used is according to the PAndAS survey.
The image used as a color inset is only a short exposure layer as the processed image is much deeper with saturated luminance.
This image uses data obtained primarily with telephoto lenses. EQ5 and Avalon M-zero Obs mount.
This image is distributed in full-resolution as CC0 but for its use please refer to what is indicated in the info here: www.flickr.com/people/133259498@N05/
Full resolution image is obtainable only upon reasonable request.
Ultra-deep imaging of M33: exploring its stellar halo
Ultra-deep imaging of M33: exploring its stellar halo
Credit: Giuseppe Donatiello
Triangulum Galaxy Extended Halo - And450 survey (sample)
by Giuseppe Donatiello flic.kr/p/2q7MZSG
Triangulum Galaxy (M33) extends well beyond its disk in a radius of some degrees. In this region, excluding the dust cirrus clouds, there is a system of faint stellar streams and debris produced by the tidal destruction of dwarf galaxies.
Such structures are extremely weak, but they can be highlighted with an appropriate treatment of the data (it is not a simple "inverted") that enhances the latent signal.
(J2000) RA: 01h 33m 50.02s Dec: +30° 39′ 36.7″
Messier 33 is a low-luminosity flocculent spiral galaxy at 3 million light-years in Triangulum. It is catalogued also as NGC 598 and known as Triangulum Galaxy. The galaxy is the smallest spiral galaxy in the Local Group and it is believed to be a big satellite of the Andromeda Galaxy.
M33 has two asymmetric faint arms, and an interstellar medium rich in gaseous filaments that extends for about 7 kpc. Although the inner disk is relatively undisturbed, the northern arm is less regular in shape than the southern one. M33, is a bulge-free galaxy with only two optically luminous dwarf galaxies believed to be its satellites: AndXXII (McConnachie et al., 2009; Martin et al., 2016) and Pisces VII (Martínez-Delgado et al., 2022) m discovered by me in 2020. However, given its mass, ΛCDM cosmological simulations predict that M33 should host a larger number of satellites, at least 10.
The neutral hydrogen (HI) disk is three times larger than the star-forming disk and is clearly warped. The outer disk has the same inclination as the inner one with respect to our line of sight but the position angle of the major axis changes by about 30 degrees compared to the inner disk and is more aligned with the M31 direction. While M33's undisturbed inner disk indicates that no major collisions between M31 and M33 or between M33 and a satellite have occurred in the past, the distortion could be the result of a flyby about 9 billion years ago. Timing assessments make this scenario unlikely and favor the hypothesis of a first fall of M33 in the region of influence of M31.
The image is a panel from my And450 photo survey that I have been doing for a few years.
The nomenclature used is according to the PAndAS survey.
The image used as a color inset is only a short exposure layer as the processed image is much deeper with saturated luminance.
This image uses data obtained primarily with telephoto lenses. EQ5 and Avalon M-zero Obs mount.
This image is distributed in full-resolution as CC0 but for its use please refer to what is indicated in the info here: www.flickr.com/people/133259498@N05/
Full resolution image is obtainable only upon reasonable request.