Search results
May 9, 2022 · Elliptical galaxies have an even, ellipsoidal shape. They typically contain a much greater proportion of older stars than spiral galaxies do. Four classes are used to classify galaxies: spiral; barred spiral; elliptical and irregular. Elliptical galaxies have a smooth ellipsoidal or spherical appearance, and they have far less structure than ...
160 Elliptical Galaxies Elliptical galaxies are those galaxies classified according to their shape and size. The shapes go from round – soccer-ball like – to extreme elongated – football-like – and are classified E0 (soccer ball shapes) to E5 (football shapes).Elliptical galaxies have very little dust and gas, and appear to be the oldest class of galaxies.
People also ask
Why do elliptical galaxies have different names?
What are elliptical galaxies?
How are elliptical and irregular galaxies different?
Do elliptical galaxies form stars?
Elliptical galaxies consist almost entirely of old stars and have shapes that are spheres or ellipsoids (somewhat squashed spheres) (Figure 13.8.4 13.8. 4 ). They contain no trace of spiral arms. Their light is dominated by older reddish stars (the population II stars discussed in The Milky Way Galaxy).
- 1 Introduction
- 2 The Simulation
- 3 The Semi-Analytic Model
- 4 The Star Formation History of Elliptical Galaxies
- 5 The Distribution of Ages and Metallicity
- 6 Discussion and Conclusions
- Acknowledgments
Elliptical galaxies are the most massive stellar systems in the local Universe and appear to define a homogeneous class of objects with uniformly old and red populations, negligible amounts of gas and very little star formation. Their deceptively simple appearance inspired a ‘classical’ formation scenario in which they form in a single intense burs...
In this study, we analyse a large collisionless cosmological simulation which follows N= 21603 particles of mass 8.6 × 108h−1 M⊙ within a comoving box of size 500 h−1 Mpc on a side (Springel et al. 2005). The spatial resolution is 5 h−1 kpc, available everywhere in the periodic box. The cosmological model is a ΛCDM model with parameters Ωm= 0.25, Ω...
Our technique for grafting the semi-analytic model onto the Millennium Simulation is similar in spirit to that used by Springel et al. (2001) and De Lucia, Kauffmann & White (2004b), but has been updated in a number of important points. A full description of the model is given by Springel et al. (2005) and Croton et al. (2006), but we here give a b...
As discussed earlier, the uniformly red and old stellar populations of elliptical galaxies have traditionally been interpreted as evidence for a formation scenario in which these galaxies form in a single intense burst of star formation at high redshift and then passively evolve to the present day. Direct observations of the formation and evolution...
We now turn to an analysis of the distribution of ages and metallicities of model elliptical galaxies as a function of stellar mass and environment. In Fig. 4, we show the distribution of the formation redshifts for model elliptical galaxies. We define the formation redshift as the redshift when 50 per cent (or 80 per cent) of the stars that make u...
We have combined a large high-resolution cosmological N-body simulation with semi-analytic techniques to investigate the formation and evolution of elliptical galaxies in a hierarchical merger model. Understanding the formation and the evolution of these systems represents an issue of fundamental interest as 50 per cent or more of the stellar mass ...
GDL would like to thank M. Pannella and V. Strazzullo for intense and provocative discussions on our poor knowledge of galaxy formation and evolution. We thank B. Poggianti and A. Aragón-Salamanca for useful comments and stimulating discussions. GDL thanks the Alexander von Humboldt Foundation, the Federal Ministry of Education and Research and the...
- Gabriella De Lucia, Volker Springel, Simon D. M. White, Darren Croton, Guinevere Kauffmann
- 2006
The situation with spiral galaxies is apparently very different. The bulges of these galaxies formed early, like the elliptical galaxies (Figure 28.27). However, the disks formed later (remember that the stars in the disk of the Milky Way are younger than the stars in the bulge and the halo) and still contain gas and dust.
Nov 21, 2023 · Astronomers have identified three types of galaxies based on their shapes: elliptical, spiral, and irregular. Elliptical galaxies are shaped like spheres or cucumbers and contain old stars that ...
May 23, 1992 · of galaxies, according to astronomers in the US. The discovery could mean. that scientists’ estimates of the distances to these galaxies are wrong. Elliptical galaxies are ellipsoidal in shape ...
