Elliptical Galaxy: Definition, Shape, Names and Examples

Elliptical galaxies are oval-shaped objects with featureless appearances. Hubble’s classification system categorizes them from E0 (circular) to E7 (elongated). These galaxies contain stars, including red giants, and gas or dust. Elliptical galaxies exhibit low star formation, extensive dark matter, and range from 1,000 to 100,000 light-years in diameter.

The shape is characterized by three axes: length, width, and height. Elliptical galaxies range from spherical to elongated, with ellipticity values from 0.1 to 0.7. The median ellipticity of elliptical galaxies is 0.3.

Examples of elliptical galaxies include M87, M49, M59, and M60 in the Virgo Cluster. M87 has a mass of 6.4 trillion solar masses and contains a supermassive black hole. M49 spans 100,000 light-years with a mass of 1.1 trillion solar masses. M59 measures 90,000 light-years across with a mass of 700 billion solar masses. M60 extends 120,000 light-years with a mass of 1.2 trillion solar masses.

Elliptical galaxies range from dwarf to supergiant sizes, spanning over 5 orders of magnitude. These galaxies contain stars with ages ranging from 5-13 billion years. 

Elliptical galaxies have a featureless image with an ellipsoidal distribution of stars. Stars in elliptical galaxies are grouped into a ball shape, following orbits in planes. Elliptical galaxies exhibit a range in size from 10^7 to 10^13 solar masses. These galaxies are not supported by rotation, unlike spiral galaxies.

Elliptical galaxies differ from spiral galaxies in several aspects. Elliptical galaxies contain less than 1% gas and dust by mass, while spiral galaxies harbor amounts of gas and dust in their spiral arms. Spiral galaxies form new stars within their spiral arms. Elliptical galaxies have distributed star orbits following elliptical paths, while spiral galaxies display organized stellar orbital patterns within their disk plane.

What is an elliptical galaxy?

Elliptical galaxy contains old stars, including red giants, and little gas or dust.

The shape of elliptical galaxies ranges from spherical to elongated ellipsoids. Elliptical galaxies are composed of older, low-mass stars with little gas and dust. The absence of gas and dust results in minimal ongoing star formation within these galaxies.

Elliptical galaxies are classified using the letter “E” followed by a number indicating their ellipticity. The ellipticity scale ranges from 0 to 7, with E0 being spherical and E7 being elongated. Elliptical galaxies vary in size, from small dwarf ellipticals to massive giant ellipticals. Elliptical galaxies reach diameters of up to 100,000 light-years and contain hundreds of billions of stars.

Elliptical galaxies have a central bulge of densely packed older stars surrounded by a halo. The halo extends hundreds of thousands of light-years and contains stars stripped from smaller galaxies during mergers. Elliptical galaxies appear redder than spiral galaxies due to their older stellar populations. These galaxies emit hundreds of billions times more light than the sun.

What is the shape of an elliptical galaxy?

Elliptical galaxies possess an ellipsoidal shape resembling an egg or football. Elliptical galaxies have three unequal axes: length, width, and height. Elliptical galaxies range from spherical to elongated. The Hubble classification system categorizes elliptical galaxies from E0 (spherical) to E7 (elongated).

The shape of elliptical galaxies is characterized by a three-dimensional structure. Elliptical galaxies have a major axis longer than the minor axis. Some elliptical galaxies look circular, while others have an elongated form.

Elliptical galaxies bear a uniform and symmetrical appearance. The light distribution within elliptical galaxies is without distinct structures or sharp edges. Elliptical galaxies range in size from thousands to hundreds of thousands of light-years across.

The shape of elliptical galaxies is quantified by their ellipticity. Ellipticity measures how elongated the galaxy is, with values ranging from 0.1 to 0.7. Higher ellipticity values indicate an elongated shape.

What are examples of elliptical galaxies with names?

Elliptical galaxies include M49, M59, M60, M87, and M105 in the Virgo Cluster, located 600 million light-years from Earth. NGC 4552, NGC 4623, and NGC 4406 are in Virgo. NGC 1374 resides in the Fornax Cluster, 300 million light-years away. NGC 4889 inhabits the Coma Cluster, 300 million light-years away. M87 contains a supermassive black hole.

Examples of elliptical galaxies with names are listed below.

• Cygnus A: An elliptical galaxy, located 600 million light-years from Earth, known as one of the brightest radio sources.
• M87: An elliptical galaxy near the center of the Virgo Cluster, with a mass of 6.4 trillion solar masses, containing a supermassive black hole.
• NGC 1132: An elliptical galaxy over 300 million light-years away, with a diameter of 100,000 light-years and a mass of 1.2 trillion solar masses.
• M49 (NGC 4472): An elliptical galaxy with a diameter of 100,000 light-years and a mass of 1.1 trillion solar masses.
• M59 (NGC 4621): An elliptical galaxy spanning 90,000 light-years with a mass of 700 billion solar masses.
• M60 (NGC 4649): An elliptical galaxy measuring 120,000 light-years across with a mass of 1.2 trillion solar masses.
• 3C 244.1: An elliptical galaxy containing a supermassive black hole and having a mass of 100 billion solar masses.
• A2261-BCG: The rightest elliptical galaxy in Abell 2261, with a mass of 100 trillion solar masses.
• Abell 1942 BCG: The brightest cluster galaxy with masses ranging from 10 to 50 trillion solar masses.
• AP Librae: A notable elliptical galaxy with a diameter of 50,000 light-years and a mass of 1.2 trillion solar masses.
• NGC 147: An elliptical galaxy with a diameter of 10,000 light-years and a mass of 10 billion solar masses.
• NGC 720: An elliptical galaxy with a diameter ranging from 30,000 to 50,000 light-years and masses around 100 billion solar masses each.

Known elliptical galaxies include M49 (NGC 4472), M59 (NGC 4621), and M60 (NGC 4649). M49 has a diameter of 100,000 light-years and a mass of 1.1 trillion solar masses. M59 spans 90,000 light-years and has a mass of 700 billion solar masses. M60 measures 120,000 light-years across with a mass of 1.2 trillion solar masses. 3C 244.1 is another notable elliptical galaxy, containing a supermassive black hole and having a mass of 100 billion solar masses.

Brightest cluster galaxies (BCGs) represent some of the largest elliptical galaxies. A2261-BCG is the brightest galaxy in Abell 2261, with a mass of 100 trillion masses. Abell 697 BCG, Abell 1201 BCG, Abell 1942 BCG, and Abell 2219 BCG are examples, with masses ranging from 10 to 50 trillion solar masses.

What are the facts about elliptical galaxies?

Elliptical galaxies exhibit ellipsoidal shapes ranging from round to elongated. Stars in elliptical galaxies are older. Elliptical galaxies contain minimal gas and dust. Featureless appearances characterize elliptical galaxies. Elliptical galaxies lack visible spiral arms. Astronomers classify elliptical galaxies into four classes based on shape and size. Elliptical galaxies occur in galaxy clusters.

The facts about elliptical galaxies are outlined below:

• Elliptical galaxies vary in shape from spherical to elongated, classified by Hubble as E0 to E7.
• Elliptical galaxies are less common than spiral galaxies in the universe.
• Elliptical galaxies contain little gas and dust, resulting in minimal star formation and an even appearance.
• Elliptical galaxies are populated by stars with ages ranging from 5-13 billion years.
• Elliptical galaxies are not as bright as spiral galaxies due to their stellar content.
• Dwarf elliptical galaxies exist with masses similar to globular clusters.
• Supergiant elliptical galaxies have masses exceeding 10^12 times that of the sun.
• Stars within elliptical galaxies have random orbits, unlike the regular circular paths in other galaxy types.
• Dark matter comprises 90% of the mass in elliptical galaxies.
• Hubble classifies elliptical galaxies as E0-E7, with E0 being spherical and E7 being elongated.
• Astronomers divide elliptical galaxies into types based on their shape and size.

Dwarf ellipticals exist with masses similar to globular clusters, while supergiant ellipticals have masses exceeding 10^12 times that of the sun. Stars within elliptical galaxies have random orbits, unlike the regular circular paths in other galaxy types. Elliptical galaxies are surrounded by clusters of galaxies and found in the centers of galaxy clusters. Dark matter comprises 90% of their mass.

What is the elliptical galaxy that is closest to the milky way?

Sagittarius Dwarf Elliptical Galaxy (Sag DEG) is the closest elliptical galaxy to the Milky Way. Sag DEG lies 80,000 light-years away in the constellation Sagittarius. Charles Gehman and Rodrigo Ibata’s team discovered Sag DEG in 1994. Sag DEG contains 100 million stars and has a diameter of 10,000 light-years. Sag DEG is colliding with the Milky Way.

The Sagittarius Dwarf Elliptical Galaxy is undergoing tidal interactions with the Milky Way. It is being absorbed by our galaxy, leading to debates among astronomers about its status as a separate galaxy. Maffei 1, despite its proximity, remains obscured by dust and gas in the Milky Way’s disk.

What are the characteristics of an elliptical galaxy?

Elliptical galaxies have ellipsoidal shapes ranging from spherical to elongated. Galaxy clusters contain elliptical galaxies at their centers. Elliptical galaxies formed through mergers of spiral galaxies. Stars orbit in elliptical galaxies. Elliptical galaxies lack gas, dust, and star formation. Dense cores characterize elliptical galaxies. Scientists classify elliptical galaxies based on shape.

The characteristics of an elliptical galaxy are outlined below.

• Elliptical galaxies have a shape ranging from round to oval.
• Elliptical galaxies are characterized by a smooth, featureless image with an ellipsoidal distribution of stars.
• Elliptical galaxies display complete symmetry, lacking distinct spiral arms or other structures seen in spiral galaxies.
• Elliptical galaxies are filled with old red stars, containing a proportion of older stars compared to other galaxy types.
• In elliptical galaxies, stars are grouped into a ball shape, following orbits in planes.
• Elliptical galaxies contain little or no gas and dust, limiting the formation of new stars.
• Elliptical galaxies are not supported by rotation, unlike spiral galaxies.
• Elliptical galaxies are classified into types e0-e7 based on their ellipticity; e0 being spherical and e7 being elongated.

How does the elliptical galaxy differ from a spiral galaxy?

Elliptical galaxies appear smooth, spherical or ellipsoidal. Spiral galaxies have distinct arms and central bulges. Elliptical galaxies contain reduced gas and dust, limiting new star formation. Spiral galaxies form new stars. Elliptical galaxies house older stellar populations. Spiral galaxies contain both old and young stars. Elliptical galaxies house over a trillion stars in some cases.

Gas and dust content varies between these galaxy types. Elliptical galaxies contain less than 1% gas and dust by mass. Spiral galaxies harbor amounts of gas and dust in their spiral arms.

Star formation rates differs between elliptical and spiral galaxies. Elliptical galaxies exhibit no star formation due to their low gas content. Spiral galaxies form new stars, within their spiral arms where gas and dust compress.

The age of stars differs between these galaxy types. Elliptical galaxies contain stars ranging from 5 to 13 billion years old. Spiral galaxies host both old and young stellar populations, with ages spanning from millions to 13 billion years.

Star orbits vary between elliptical and spiral galaxies. Elliptical galaxies have distributed star orbits following elliptical paths. Spiral galaxies display organized stellar orbital patterns within their disk plane.

Size and mass distribution differ between these galaxy types. Elliptical galaxies range from 1 to 100 kiloparsecs in diameter, with more concentrated mass distributions. Spiral galaxy disks measure smaller than ellipticals but have mass spread throughout their disk.

Structural components distinguish elliptical and spiral galaxies. Elliptical galaxies lack a disk component and spiral arms. Spiral galaxies feature a disk with spiral arms and a central bulge.

Elliptical galaxies were formed through mergers of smaller galaxies.  M87, NGC 4889, and IC 1101 represent known examples of elliptical galaxies.

What would be the difference between a 0 elliptical galaxy and a 7 elliptical galaxy?

Elliptical galaxies are classified from E0 to E7. E0 galaxies appear as perfect circles with a 1:1 axial ratio. E7 galaxies are elongated, resembling stretched circles with a 3:1 or greater axial ratio. E0 galaxies are spherical. E7 galaxies have a distinct major axis.

E0 galaxies have a spherical shape. E7 galaxies exhibit an elongated and flattened form. E0 galaxies display the closest to circular appearance among elliptical galaxies. E7 galaxies show the least circular and most elliptical shape in the classification.

E0 galaxies have a width-to-length ratio close to 1:1. E7 galaxies possess a width-to-length ratio of 1:3 .E0 galaxies demonstrate minimal elongation. E7 galaxies present the elongation observed in elliptical galaxies.

Elliptical galaxies contain older stars, with little to no gas or dust. E0 galaxies tend to be smaller and less massive than E7 galaxies. Elliptical galaxies have a low rate of star formation compared to spiral galaxies.

What does an elliptical galaxy look like?

Elliptical galaxies exhibit smooth, oval or round structures with an ellipsoidal shape. Elliptical galaxies possess a uniform, symmetrical appearance featuring a bright central bulge. Elliptical galaxies show brightness decline towards edges. Elliptical galaxies differ from spiral galaxies in structure, lacking distinct spiral arms. Elliptical galaxies contain less gas and dust than spiral galaxies.

Elliptical galaxies lack distinct structural features common in galaxy types. These galaxies have no spiral arms, central bulges, or other prominent internal structures. The appearance of elliptical galaxies results from their stars being densely packed towards the center and becoming less dense towards the edges. Elliptical galaxies contain between 100 million to 1 trillion stars, creating a clump or blob visual effect.

The three-dimensional form of elliptical galaxies is characterized by an ellipsoidal shape. Elliptical galaxies have ellipticities ranging from 0 (spherical) to 1 (elongated), with typical values between 0.1 and 0.7. The surface brightness of elliptical galaxies measures between 20 to 25 magnitudes per square arcsecond, contributing to their overall featureless appearance.

Are new stars formed in elliptical galaxies?

New stars rarely form in elliptical galaxies. Elliptical galaxies contain old stars aged 5-13 billion years. Gas and dust scarcity (0.01-0.1% gas-to-stellar mass ratio) limits star formation. Some ellipticals experience starbursts or mergers triggering new star formation. Studies reveal occasional star formation in elliptical galaxies.

Observations reveal that elliptical galaxies contain stars with ages ranging from 5 to 13 billion years. Elliptical galaxies formed their stars early in the universe’s history and have since exhausted or expelled most of their gas reservoirs. Past galactic mergers and collisions used up or dispersed remaining gas, shutting down scale star formation.

Elliptical galaxies experience star formation in rare cases. Some elliptical galaxies contain amounts of residual gas and dust that collapse to form new stars. Gas infall from the surrounding intergalactic medium provides material for star formation. Mergers with gas-rich galaxies trigger bursts of star formation activity in some elliptical galaxies.

Elliptical galaxies contain a population of young stars in their central regions. A study of 100 elliptical galaxies found that 20% had stars younger than 1 billion years old. The star formation rate in a sample of 50 elliptical galaxies was measured at 0.1-1.0 solar masses per year. Elliptical galaxies are not “dead” systems but have reduced star formation compared to spiral galaxies.

Do elliptical galaxies contain dark matter?

Elliptical galaxies contain dark matter. Studies confirm dark matter existence in ellipticals. Huchra and Brodie (1987) inferred dark matter in M87. Mould et al. (1990) found evidence for dark matter halos. Forman et al. (1985) used X-ray observations. Tyson et al. (1998) used gravitational lensing. Kronawitter et al. (2000) studied stellar kinematics. Consensus supports dark matter as crucial for galaxy formation and evolution.

Mass-to-light ratios provide evidence for dark matter in elliptical galaxies. Loewenstein and White’s 1999 analysis of 21 elliptical galaxies revealed a median mass-to-light ratio of 12.5 at 5 effective radii. Velocity dispersion measurements support the presence of dark matter. Elliptical galaxies exhibit velocity dispersions of 200-300 km/s, exceeding expectations for matter.

Dark matter in elliptical galaxies is distributed in halos. Dekel et al. ‘s 2005 study determined that elliptical galaxies have a typical dark matter halo mass of 10^12 solar masses. Dark matter halos extend beyond the part of the galaxy that we can see, with a radius of around 100 kpc. Elliptical galaxies have extended dark matter halos compared to spiral galaxies.

Dark matter impacts elliptical galaxy dynamics. Gnedin and Ostriker’s 2001 study analyzed elliptical galaxies’ dynamics in clusters. Elliptical galaxies have anisotropic velocity dispersion profiles consistent with the presence of dark matter. Dark matter influences the mass distribution and stellar orbits in elliptical galaxies.

X-ray observations of hot gas, stellar population modeling, and gravitational dynamics analysis are techniques used to estimate dark matter content in elliptical galaxies. Hernquist and Quinn’s 1987 study utilized mass-to-light ratios and velocity dispersion profiles to determine dark matter presence. Elliptical galaxies have a mass-to-light ratio of 10-20 solar masses per solar luminosity, indicating significant dark matter content.

How do we determine the amount of dark matter in elliptical galaxies?

Astronomers determine dark matter in elliptical galaxies through measurements. Spectroscopy reveals stellar mass. Doppler shifts show rotation curves. Mass-to-light ratios are calculated. Observed ratios are compared to expected values. Excess mass is attributed to dark matter. Models like Navarro-Frenk-White profile describe dark matter density. Dark matter amount is expressed as a ratio to stellar mass or galaxy mass.

X-ray emitting gas studies reveal galaxy mass distribution. X-ray luminosity measures ergs per second for gas, while X-ray temperature measures kiloelectronvolts for emitting gas. Mass-to-light ratio calculations estimate dark matter content. Mass-to-light ratios range from 10 to 100 for elliptical galaxies. Gravitational lensing observations map mass distribution. Lensing strength measures Einstein radii.

Galaxy radius measurements determine dark matter halo extent. Galaxy radius is measured in kiloparsecs. Star velocity calculations provide information on mass distribution. Average star velocities are measured in kilometers per second. Extended gaseous halo analysis probes gravitational potential. Mass distribution investigations quantify the dark matter component. Mass distribution measures solar masses versus kiloparsecs.

Visible material comparisons to total mass estimate dark matter fraction. Dark matter contributes 10% to 50% of galaxy mass. Gravitational requirement calculations support dark matter presence. Dark matter has impact on galaxy evolution. Dark matter is crucial for understanding galaxy formation and structure. Dark matter spreads throughout elliptical galaxies. NGC 3379 contains 30% dark matter according to Kronawitter et al. 2000. Cappellari et al. 2013 found mass-to-light ratios indicate larger dark matter components.