Six Images by Chandra

Chandra Archive Collection: Six images that combine Chandra data with those from other telescopes.

With the passing of Chandraʼs 15th anniversary, the Chandra Data Archive, which houses all of the missionʼs data, continues to grow each successive year. These images – that include a wide range of astronomical objects -- combine X-rays from Chandraʼs archive with data from other telescopes. This technique of creating “multi-wavelength” images allows scientists and the public to see how X-rays fit with data of other types of light, such as optical, radio, and infrared.

PSR B1509-58 (upper left)
Pareidolia is the psychological phenomenon where people see recognizable shapes in clouds, rock formations, or otherwise unrelated objects or data. When Chandra's image of PSR B1509-58, a spinning neutron star surrounded by a cloud of energetic particles, was released in 2009, it quickly gained attention because many saw a hand-like structure in the X-ray emission. In this new image of the system, X-rays from Chandra in gold are seen along with infrared data from NASA's Wide-field Infrared Survey Explorer (WISE) telescope in red, green, and blue. Pareidolia may strike again in this image as some people report seeing a shape of a face in WISE's infrared data.

RCW 38 (upper right)
A young star cluster about 5,500 light years from Earth, RCW 38 provides astronomers a chance to closely examine many young, rapidly evolving stars at once. In this composite image, X-rays from Chandra are blue, while infrared data from NASA's Spitzer Space Telescope are orange and additional infrared data from the 2MASS survey appears white. There are many massive stars in RCW 38 that will likely explode as supernovas. Astronomers studying RCW 38 are hoping to better understand this environment as our Sun was likely born into a similar stellar nursery.

Hercules A (middle left):
Some galaxies have extremely bright cores, suggesting that they contain a supermassive black hole that is pulling in matter at a prodigious rate. Astronomers call these "active galaxies," and Hercules A is one of them. In visible light (colored red, green and blue, with most objects appearing white), Hercules A looks like a typical elliptical galaxy. In X-ray light, however, Chandra detects a giant cloud of multimillion-degree gas (purple). This gas has been heated by energy generated by the infall of matter into a black hole at the center of Hercules A that is over 1,000 times as massive as the one in the middle of the Milky Way. Radio data (blue) show jets of particles streaming away from the black hole. The jets span a length of almost one million light years.

Kes 73 (middle right):
The supernova remnant Kes 73, located about 28,000 light years away, contains a so-called anomalous X-ray pulsar, or AXP, at its center. Astronomers think that most AXPs are magnetars, which are neutron stars with ultra-high magnetic fields. Surrounding the point-like AXP in the middle, Kes 73 has an expanding shell of debris from the supernova explosion that occurred between about 750 and 2100 years ago, as seen from Earth. The Chandra data (blue) reveal clumpy structures along one side of the remnant, and appear to overlap with infrared data (orange). The X-rays partially fill the shell seen in radio emission (red) by the Very Large Array. Data from the Digitized Sky Survey optical telescope (white) show stars in the field-of-view.

Mrk 573 (lower left):
Markarian 573 is an active galaxy that has two cones of emission streaming away from the supermassive black hole at its center. Several lines of evidence suggest that a torus, or doughnut of cool gas and dust may block some of the radiation produced by matter falling into supermassive black holes, depending on how the torus is oriented toward Earth. Chandra data of Markarian 573 suggest that its torus may not be completely solid, but rather may be clumpy. This composite image shows overlap between X-rays from Chandra (blue), radio emission from the VLA (purple), and optical data from Hubble (gold).

NGC 4736 (lower right):
NGC 4736 (also known as Messier 94) is a spiral galaxy that is unusual because it has two ring structures. This galaxy is classified as containing a "low ionization nuclear emission region," or LINER, in its center, which produces radiation from specific elements such as oxygen and nitrogen. Chandra observations (gold) of NGC 4736, seen in this composite image with infrared data from Spitzer (red) and optical data from Hubble and the Sloan Digital Sky Survey (blue), suggest that the X-ray emission comes from a recent burst of star formation. Part of the evidence comes from the large number of point sources near the center of the galaxy, showing that strong star formation has occurred. In other galaxies, evidence points to supermassive black holes being responsible for LINER properties. Chandra's result on NGC 4736 shows LINERs may represent more than one physical phenomenon.

Image credit: NASA/CXC/SAO

Note: For more information, see Chandra Archive Collection: Chandra's Archives Come to Life.

Magnetar 3XMM J185246.6+003317 Below Supernova Remnant Kesteven 79

Massive stars end their life with a bang, exploding as supernovas and releasing massive amounts of energy and matter. What remains of the star is a small and extremely dense remnant: a neutron star or a black hole.

Neutron stars come in several flavors, depending on properties such as their ages, the strength of the magnetic field concealed beneath their surface, or the presence of other stars nearby. Some of the energetic processes taking place around neutron stars can be explored with X-ray telescopes, like ESA's XMM-Newton.

This image depicts two very different neutron stars that were observed in the same patch of the sky with XMM-Newton. The green and pink bubble dominating the image is Kesteven 79, the remnant of a supernova explosion located about 23,000 light-years away from us.

From the properties of the hot gas in Kesteven 79 and from its size, astronomers estimate that it is between 5000 and 7000 years old. Taking account of the time needed for light to travel to Earth, this means that the supernova that created it must have exploded almost 30,000 years ago. The explosion left behind a young neutron star with a weak magnetic field, which can be seen as the blue spot at the center of Kesteven 79.

Beneath it, a blue splotch indicates an entirely different beast: a neutron star boasting an extremely strong magnetic field, known as a magnetar. Astronomers discovered this magnetar, named 3XMM J185246.6+003317, in 2013 by looking at images that had been taken in 2008 and 2009. After the discovery, they looked at previous images of the same patch of the sky, taken before 2008, but did not find any trace of the magnetar. This suggests that the detection corresponded to an outburst of X-rays released by the magnetar, likely caused by a dramatic change in the structure of its magnetic field.

While the neutron star in the supernova remnant is relatively young, the magnetar is likely a million years old; the age difference means that it is very unlikely that the magnetar arose from the explosion that created Kesteven 79, but must have formed much earlier.

This false-color image is a composite of 15 observations performed between 2004 and 2009 with the EPIC MOS camera on board XMM-Newton. The image combines data collected at energies from 0.3 to 1.2 keV (shown in red), 1.2 to 2 keV (shown in green) and 2 to 7 keV (shown in blue).

Image credit: ESA/XMM-Newton/ Ping Zhou, Nanjing University, China

Artist’s Impression of the Magnetar in the Star Cluster Westerlund 1

This artist’s impression shows the magnetar in the very rich and young star cluster Westerlund 1. This remarkable cluster contains hundreds of very massive stars, some shining with a brilliance of almost one million suns. European astronomers have for the first time demonstrated that this magnetar — an unusual type of neutron star with an extremely strong magnetic field — probably was formed as part of a binary star system. The discovery of the magnetar’s former companion elsewhere in the cluster helps solve the mystery of how a star that started off so massive could become a magnetar, rather than collapse into a black hole.

Illustration credit: ESO/L. Calçada

Note: For more information, see Magnetar Formation Mystery Solved?

Magnetar SGR 0418+5729 With a Magnetic Loop

This image shows an artist's impression of the magnetar SGR 0418+5729.

Magnetars are peculiar pulsars – the spinning remnants of massive stars – that are characterised by unusually intense magnetic fields. Astronomers discovered them through their exceptional behavior at X-ray wavelengths, including sudden outbursts of radiation and occasional giant flares. These peculiar features of magnetars are caused by their extremely strong magnetic fields, which range between 1014 and 1015 Gauss (G) and are hundreds or thousands of times more intense than those of regular pulsars.

Since it was discovered in 2009, SGR 0418+5729 has been puzzling astronomers. Its dipolar magnetic field – the most direct manifestation of a magnetar's average magnetic field, which can be estimated from its spin-down rate – is about two orders of magnitude lower than other magnetars. Astronomers believed that this magnetar concealed, in its interior, a very strong magnetic field. A study based on data from ESA's XMM-Newton X-ray Observatory has found evidence to confirm this, revealing that the magnetar's internal field may even exceed 1015 G, removing any lingering doubts about the object's true identity.

The strong internal magnetic field of this magnetar reveals itself only in a small feature emerging from its surface, where protons absorb some of the X-rays emitted by the magnetar. The protons are confined in this region by a strong and localized magnetic field, with lines that are probably shaped like a series of adjacent arcs, resembling the appearance of loops on the surface of the Sun.

Illustration credit: ESA/ATG medialab

Note: For more information, see Weakling Magnetar Reveals Hidden Strength; also, Magnetic Loop on Magnetar SGR 0418.

SGR 0418+5729

SGR 0418+5729: A magnetar located in our galaxy, about 6,500 light years from Earth.

This graphic shows a magnetar called SGR 0418+5729 (SGR 0418 for short), a type of neutron star that has a relatively slow spin rate and generates occasional large blasts of X-rays. Most magnetars have extremely high magnetic fields on their surface that are ten to a thousand times stronger than for the average neutron star. New data from NASA’s Chandra X-ray Observatory, ESA’s XMM-Newton and NASA's Swift and RXTE satellites shows that SGR 0418 is exceptional, with a surface magnetic field similar to that of mainstream neutron stars. In the image on the left, data from Chandra shows SGR 0418 as a pink source in the middle. Optical data from the William Herschel telescope in La Palma and infrared data from NASA’s Spitzer Space Telescope are shown in red, green and blue. On the right is an artist’s impression giving a close-up view of SGR 0418. This illustration highlights the weak surface magnetic field of the magnetar, and the relatively strong, wound-up magnetic field lurking in the hotter interior of the star. SGR 0418 is located about 6,500 light years from Earth.

Scale: Image is about 2 arcmin across. (about 3 light years).

Image credit: X-ray: NASA/CXC/CSIC-IEEC/N.Rea et al; Optical: Isaac Newton Group of Telescopes, La
Palma/WHT; Infrared: NASA/JPL-Caltech; Illustration: NASA/CXC/M.Weiss.

Note: For more information, see SGR 0418+5729: A Hidden Population of Exotic Neutron Stars.

New Understanding of Magnetars

This illustration depicts a magnetar: a spinning neutron star, characterized by rotation periods between 2 and 10 seconds, occasional episodes of extremely enhanced emission, and intense, short bursts of X-rays and gamma rays; these highly energetic events are presumed to be powered by an intense magnetic field.

A new, comprehensive study of the magnetar 1E 1547.0-5408 (see Kuiper et al., 2012), using data from INTEGRAL, RXTE and Swift, revealed unusual behavior - the creation of both pulsed and unpulsed luminous non-thermal X-ray emission after a star quake. This is consistent with a model (Beloborodov, 2009) in which a star quake twists magnetic field lines that are anchored to the star's surface. When these twisted lines unravel they release magnetic energy and produce the observed radiation.

In this illustration, the curves converging at the poles of the magnetar represent the dipolar magnetic field lines; the entangled lines inside the magnetar symbolize the internal magnetic field.

Illustration credit: ESA

Note: For more information, see Massive Glitch Moves Magnetar Modeling Forward.

Magnetar SGR 0418+5729

This illustration represents the recently discovered magnetar SGR 0418+5729.

Magnetars are pulsars (spinning neutron stars) characterized by long rotations periods, occasional episodes of extremely enhanced emission (about 10–100 times the usual value) and intense, short bursts of X-rays and gamma-rays; these highly energetic events are presumed to be powered by an intense magnetic field.

Unlike all other magnetars detected so far, SGR 0418+5729 has a relatively weak dipolar magnetic field, B<7.5 x 1012 Gauss, which is 2–3 orders of magnitude lower than the typical value for a magnetar. Astronomers deduce that the magnetar-like activity of SGR 0418+5729 is powered by a strong, internal magnetic field, B~5 x 1014 Gauss, which is undetectable by observations.

The curves converging at the poles of the magnetar represent the dipolar magnetic field lines, whereas the entangled lines inside the magnetar symbolize the internal magnetic field.

Illustration credit: European Space Agency

Notes: For more information, see Are Most Pulsars Really Magnetars in Disguise? The initials "SGR" stand for "Soft Gamma Repeater."

Magnetar in Star Cluster Westerlund 1

This artist’s impression shows the Magnetar in the very rich and young star cluster Westerlund 1. This remarkable cluster contains hundreds of very massive stars, some shining with a brilliance of almost one million suns. European astronomers have for the first time demonstrated that this magnetar — an unusual type of neutron star with an extremely strong magnetic field — was formed from a star with at least 40 times as much mass as the Sun. The result presents great challenges to current theories of how stars evolve, as a star as massive as this was expected to become a black hole, not a magnetar.

Illustration credit: ESO/L. Calçada

Photo credit: European Southern Observatory

Note: For more information and photographs, see How Much Mass Makes a Black Hole?