Normal Stars & Star Clusters

Since antiquity, wreaths have symbolized the cycle of life, death, and rebirth. It is fitting then that one of the best places for astronomers to learn more about the stellar lifecycle resembles a giant holiday wreath itself.

The star cluster NGC 602 lies on the outskirts of the Small Magellanic Cloud, which is one of the closest galaxies to the Milky Way, about 200,000 light-years from Earth. The stars in NGC 602 have fewer heavier elements compared to the Sun and most of the rest of the galaxy. Instead, the conditions within NGC 602 mimic those for stars found billions of years ago when the universe was much younger.

Most stars form in collections, called clusters or associations, that include very massive stars. These giant stars send out large amounts of high-energy radiation, which can disrupt relatively fragile disks of dust and gas that are in the process of coalescing to form new planets.

A team of astronomers used NASA’s Chandra X-ray Observatory, in combination with ultraviolet, optical, and infrared data, to show where some of the most treacherous places in a star cluster may be, where planets’ chances to form are diminished.

The target of the observations was Cygnus OB2, which is the nearest large cluster of stars to our Sun — at a distance of about 4,600 light-years. The cluster contains hundreds of massive stars as well as thousands of lower-mass stars. The team used long Chandra observations pointing at different regions of Cygnus OB2, and the resulting set of images were then stitched together into one large image.

This graphic shows a three-dimensional map of stars near the Sun. These stars are close enough that they could be prime targets for direct imaging searches for planets using future telescopes. The blue haloes represent stars that have been observed with NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton. The yellow star at the center of this diagram represents the position of the Sun. The concentric rings show distances of 5, 10, and 15 parsecs (one parsec is equivalent to roughly 3.2 light-years).

Astronomers are using these X-ray data to determine how habitable exoplanets may be based on whether they receive lethal radiation from the stars they orbit, as described in our latest press release. This type of research will help guide observations with the next generation of telescopes aiming to make the first images of planets like Earth.

Westerlund 1 is the biggest and closest “super” star cluster to Earth. New data from NASA’s Chandra X-ray Observatory, in combination with other NASA telescopes, is helping astronomers delve deeper into this galactic factory where stars are vigorously being produced.

This is the first data to be publicly released from a project called the Extended Westerlund 1 and 2 Open Clusters Survey, or EWOCS, led by astronomers from the Italian National Institute of Astrophysics in Palermo. As part of EWOCS, Chandra observed Westerlund 1 for about 12 days in total.

A colorful, festive image shows different types of light containing the remains of not one, but at least two, exploded stars. This supernova remnant is known as 30 Doradus B (30 Dor B for short) and is part of a larger region of space where stars have been continuously forming for the past 8 to 10 million years. It is a complex landscape of dark clouds of gas, young stars, high-energy shocks, and superheated gas, located 160,000 light-years away from Earth in the Large Magellanic Cloud, a small satellite galaxy of the Milky Way.

The new image of 30 Dor B was made by combining X-ray data from NASA’s Chandra X-ray Observatory (purple), optical data from the Blanco 4-meter telescope in Chile (orange and cyan), and infrared data from NASA’s Spitzer Space Telescope (red). Optical data from NASA’s Hubble Space Telescope was also added in black and white to highlight sharp features in the image.

This new image of NGC 2264, also known as the “Christmas Tree Cluster,” shows the shape of a cosmic tree with the glow of stellar lights. NGC 2264 is, in fact, a cluster of young stars — with ages between about one and five million years old — in our Milky Way about 2,500 light-years away from Earth. The stars in NGC 2264 are both smaller and larger than the Sun, ranging from some with less than a tenth the mass of the Sun to others containing about seven solar masses.

A group of dead stars known as “spider pulsars” are obliterating companion stars within their reach. Data from NASA’s Chandra X-ray Observatory of the globular cluster Omega Centauri is helping astronomers understand how these spider pulsars prey on their stellar companions.

A pulsar is the spinning dense core that remains after a massive star collapses into itself to form a neutron star. Rapidly rotating neutron stars can produce beams of radiation. Like a rotating lighthouse beam, the radiation can be observed as a powerful, pulsing source of radiation, or pulsar. Some pulsars spin around dozens to hundreds of times per second, and these are known as millisecond pulsars.

A new movie made from over two decades of data from NASA’s Chandra X-ray Observatory shows a famous star system changing with time, as described in our latest press release. Eta Carinae contains two massive stars (one is about 90 times the mass of the Sun and the other is believed to be about 30 times the Sun’s mass).

In the middle of the 19th century, skywatchers observed as Eta Carinae experienced a huge explosion that was dubbed the “Great Eruption.” During this event, Eta Carinae ejected between 10 and 45 times the mass of the Sun. This material became a dense pair of spherical clouds of gas, now called the Homunculus nebula, on opposite sides of the two stars. The Homunculus is clearly seen in a composite image of the Chandra data with optical light from the Hubble Space Telescope (blue, purple, and white).

A new time-lapse sequence contains frames of Eta Carinae taken with Chandra from 1999, 2003, 2009, 2014, and 2020. Astronomers used the Chandra observations along with data from ESA’s XMM-Newton to watch as the stellar eruption from about 180 years ago continues to expand into space at speeds up to 4.5 million miles per hour. The two massive stars produce the blue, relatively high energy X-ray source in the center of the ring. They are too close to each other to be seen individually.

NGC 346, NGC 1672, M74 & M16
Credit: X-ray: Chandra: NASA/CXC/SAO, XMM: ESA/XMM-Newton; IR: JWST: NASA/ESA/CSA/STScI, Spitzer: NASA/JPL/CalTech; Optical: Hubble: NASA/ESA/STScI, ESO; Image Processing: L. Frattare, J. Major, N. Wolk, and K. Arcand

Four composite images deliver dazzling views from NASA's Chandra X-ray Observatory and James Webb Space Telescope of two galaxies, a nebula, and a star cluster. Each image combines Chandra's X-rays — a form of high-energy light — with infrared data from previously released Webb images, both of which are invisible to the unaided eye. Data from NASA's Hubble Space Telescope (optical light) and retired Spitzer Space Telescope (infrared), plus the European Space Agency's XMM-Newton (X-ray) and the European Southern Observatory's New Technology Telescope (optical) is also used. These cosmic wonders and details are made available by mapping the data to colors that humans can perceive.