Messier 87

Messier 87, also called Virgo A or NGC 4486, is a very large galaxy in the constellation Virgo. It is one of the biggest and most massive galaxies near us, with many trillions of stars. Unlike spiral galaxies, which have arms like our own Milky Way, Messier 87 has a smooth, round shape.

The French astronomer Charles Messier found Messier 87 in 1781. It is about 53 million light-years from Earth and is the second-brightest galaxy in the Virgo Cluster. Messier 87 has many globular clusters — about 15,000 — orbiting around it. This is far more than the 150–200 around our own galaxy.

At the center of Messier 87 is a supermassive black hole. In 2019, the Event Horizon Telescope showed the first picture of this black hole. This helped scientists learn more about black holes and how they affect galaxies.

Messier 87 gives off strong radio waves and other radiation. It has a jet of energetic material stretching far from its center. Astronomers, both amateur and professional, often study this galaxy to learn more about space.

Observation history

In Hubble's galaxy classification scheme, M87 is an E0 galaxy.

In 1781, French astronomer Charles Messier made a catalogue of fuzzy things in the sky. This was to help people not confuse them for comets. M87 was the eighty-seventh object in his list. Later, it was also called NGC 4486 in another star chart by John Dreyer.

As years passed, astronomers discovered more about M87. In 1922, Edwin Hubble showed that M87 was a giant elliptical galaxy, not just a cloudy shape in the sky. In 2017, the Event Horizon Telescope took the first picture ever of a black hole’s shadow. It showed the black hole at the center of M87.

Visibility

Messier 87, or M87, is a galaxy near the edge of the Virgo constellation, close to the constellation Coma Berenices. You can see this galaxy with a small telescope, about 6 cm (2.4 in) in size. It looks about 7.2 × 6.8 arcminutes wide. The galaxy has a very bright center. Its jet can be seen with special photography. Before 1991, only one astronomer, Otto Struve, had seen the jet with a very large Hooker telescope. Today, larger amateur telescopes can sometimes see it under perfect conditions.

Properties

Stellar velocity map of the central region of M87, showing the motion of stars relative to Earth: away towardsThe image shows a slight rotation in the vertical plane (the lower right moving toward earth, the upper left moving away), showing that M87 is rotating slowly.

Messier 87, or M87, is a very big round galaxy in the constellation Virgo. It is one of the largest galaxies near us. M87 shoots out a powerful jet of energetic particles from its center.

M87 is about 132,000 light-years wide, which is larger than our own Milky Way. It has about twice as much mass as the Milky Way, most of which is not made of stars. M87 has many smaller galaxies moving around it and has taken in material from other galaxies, making it even bigger and heavier.

Enclosed mass
Radius kpc	Mass ×10¹² M_☉
32	2.4
44	3.0
47	5.7
50	6.0

Components

The core of Messier 87 has a supermassive black hole, one of the biggest we know. This black hole is billions of times heavier than the Sun. Around it is a spinning disk of hot gas, moving very fast. Scientists have pictures of this black hole, showing a dark spot where its shadow is.

Composite image showing how the M87 system looked, across the entire electromagnetic spectrum, during the Event Horizon Telescope's April 2017 campaign to take the first image of a black hole. Requiring 19 different facilities on the Earth and in space, this image reveals the enormous scales spanned by the black hole and its forward-pointing jet. It shows the image of the larger-scale jet taken by ALMA (upper left), on the same scale as the visible image by the Hubble Space Telescope (center) and the X-ray image by Chandra (upper right).

Messier 87 also sends out a strong jet of energy from its center. This jet moves almost at the speed of light and goes far from the galaxy. The jet's energy comes from the spinning black hole and can make bright spots and patterns in space. Astronomers study these jets to learn more about black holes and galaxies.

Messier 87 has many "globular clusters"—groups of stars held together by gravity. It has about 15,000 of these clusters, much more than our Milky Way galaxy, which has only about 150–200. These clusters are different in size and makeup, with many far from the galaxy's center.

Selected elemental abundances in the M87 core
Element	Abundance (solar values)
C	0.63 ± 0.16
N	1.64 ± 0.24
O	0.58 ± 0.03
Ne	1.41 ± 0.12
Mg	0.67 ± 0.05
Fe	0.95 ± 0.03

Environment

Photograph of Markarian's Chain of Galaxies, taken through a widefield telescope. M87 is visible in the bottom left corner

Main article: Virgo Cluster

Messier 87 is found at the center of the Virgo Cluster, a group of about 2,000 galaxies. This cluster is part of a much bigger structure called the Virgo Supercluster, which includes our own Local Group and the Milky Way. Messier 87 is probably the biggest galaxy in this cluster and looks very calm compared to others. The Virgo Cluster has thin, hot gas that gives off X-rays.