Messier 87

Messier 87, also called Virgo A or NGC 4486, is a giant elliptical galaxy in the constellation Virgo. It is one of the largest and most massive galaxies known, containing several trillion stars and about 15,000 globular clusters, far more than the Milky Way. A powerful jet of energetic plasma shoots out from its center, traveling at nearly the speed of light.

The French astronomer Charles Messier discovered M87 in 1781. It lies about 53 million light-years from Earth and is the second-brightest member of the Virgo Cluster of galaxies. Unlike spiral galaxies, M87 has a smooth, round shape with stars spreading out evenly from its center.

At the heart of M87 is a huge supermassive black hole, one of the first ever to be imaged by the Event Horizon Telescope. This black hole powers the galaxy’s bright center and the energetic jet that stretches far into space. M87 shines brightly in many types of light, especially radio waves, making it a favorite subject for astronomers around the world.

Observation history

In 1781, the French astronomer Charles Messier published a catalogue of fuzzy objects to help people tell them apart from comets. M87 was the eighty-seventh object in this list. Later, in the 1880s, it was added to another list called the New General Catalogue by John Dreyer.

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

In 1918, an astronomer named Heber Curtis noticed something unusual about M87 — a bright streak coming from its center. In 1922, another astronomer found evidence of a supernova, a huge explosion in a star, in M87.

Later, the famous astronomer Edwin Hubble helped us understand that M87 was a giant ball of stars, not part of our own Milky Way galaxy. He called it an elliptical galaxy.

In the 1940s and 1950s, scientists discovered that M87 was also a strong source of radio waves and had a thin, fast-moving jet shooting out from its center. In 2017, the Event Horizon Telescope made the first-ever picture of the shadow of a black hole — and it was the black hole at the center of M87!

Visibility

Messier 87, or M87, is located near the edge of the Virgo constellation, close to Coma Berenices. You can spot it with a small telescope, about 6 cm (2.4 inches) wide, though it looks small and faint. It stretches across an area of sky about 7.2 by 6.8 arcminutes. The center of M87 shines very brightly. Seeing its energetic jet without a camera is very hard and was only achieved by astronomer Otto Struve many years ago using a very large telescope.

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, also known as M87, is a giant elliptical galaxy in the constellation Virgo. It is one of the largest and most massive galaxies close to us. M87 appears almost perfectly round and is classified as a special type of galaxy because of the energetic jet that shoots out from its center.

M87 is about 132,000 light-years wide, which is larger than our own Milky Way galaxy. It contains about twice as much mass as the Milky Way, though most of this mass is not in stars but in an invisible form called dark matter. M87 has many smaller galaxies orbiting around it and is part of a large group of galaxies called the Virgo Cluster. Astronomers study M87 to learn about how big galaxies form and change over time.

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

Components

The core of the Messier 87 galaxy contains a very massive supermassive black hole, called M87*. Its mass is billions of times that of the Sun. In 2019, the Event Horizon Telescope captured the first-ever image of this black hole, showing its dark shadow surrounded by bright material.

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).

M87 also has a powerful jet shooting out from its center at nearly the speed of light. This jet stretches far from the galaxy and is made of energetic particles. Scientists study this jet to learn more about black holes and how they affect their surroundings.

The galaxy is filled with many globular clusters—about 15,000, much more than the Milky Way has. These clusters are groups of old stars bound together by gravity.

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 sits near the center of the Virgo Cluster, a dense group of about 2,000 galaxies. This cluster is part of an even larger structure called the Virgo Supercluster, which includes our own Local Group with the Milky Way. Among these galaxies, M87 is likely the largest and appears to be very still compared to others in the cluster. The space between these galaxies contains a thin, hot gas that glows in X-rays. Scientists think M87 may have interacted with nearby galaxies like M49 and M86, shaping its structure over time.