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The guitar shape in the “Guitar Nebula” comes from bubbles blown by particles ejected from the pulsar through a steady wind as it moves through space. A movie of Chandra (red) data taken in 2000, 2006, 2012, and 2021 has been combined with a single image in optical light from Palomar. X-rays from Chandra show a filament of energetic matter and antimatter particles, about two light-years long, blasting away from the pulsar (seen as the bright white dot). The movie shows how this filament has changed over two decades.
X-ray: NASA/CXC/Stanford Univ./M. de Vries et al.; Optical full field: Palomar Obs./Caltech & inset: NASA/ESA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare)

Normally found only in heavy metal bands or certain post-apocalyptic films, a “flame-throwing guitar” has now been spotted moving through space. Astronomers have captured movies of this extreme cosmic object using NASA’s Chandra X-ray Observatory and Hubble Space Telescope.

The new movie of Chandra (red) and Palomar (blue) data helps break down what is playing out in the Guitar Nebula. X-rays from Chandra show a filament of energetic matter and antimatter particles, about two light-years or 12 trillion miles long, blasting away from the pulsar (seen as the bright white dot connected to the filament).

Astronomers have nicknamed the structure connected to the pulsar PSR B2224+65 as the “Guitar Nebula” because of its distinct resemblance to the instrument in glowing hydrogen light. The guitar shape comes from bubbles blown by particles ejected from the pulsar through a steady wind. Because the pulsar is moving from the lower right to the upper left, most of the bubbles were created in the past as the pulsar moved through a medium with variations in density.

The guitar shape in the “Guitar Nebula” comes from bubbles blown by particles ejected from the pulsar through a steady wind as it moves through space. Images from Chandra taken in 2000, 2006, 2012 and 2021 have been combined with a single image in optical light from Palomar. X-rays from Chandra show a filament of energetic matter and antimatter particles, about two light-years long, blasting away from the pulsar (seen as the bright white dot). The movie shows how this filament has changed over two decades. An inset shows a closeup of the “guitar head” from NASA’s Hubble Space Telescope also changing over time from 1994-2021.
X-ray: NASA/CXC/Stanford Univ./M. de Vries et al.; Optical: (Hubble) NASA/ESA/STScI and (Palomar) Hale Telescope/Palomar/CalTech; Image Processing: NASA/CXC/SAO/L. Frattare

At the tip of the guitar is the pulsar, a rapidly rotating neutron star left behind after the collapse of a massive star. As it hurtles through space it is pumping out a flame-like filament of particles and X-ray light that astronomers have captured with Chandra.

How does space produce something so bizarre? The combination of two extremes — fast rotation and high magnetic fields of pulsars — leads to particle acceleration and high-energy radiation that creates matter and antimatter particles, as electron and positron pairs. In this situation, the usual process of converting mass into energy, famously determined by Albert Einstein’s E = mc2 equation, is reversed. Here, energy is being converted into mass to produce the particles.

Particles spiraling along magnetic field lines around the pulsar create the X-rays that Chandra detects. As the pulsar and its surrounding nebula of energetic particles have flown through space, they have collided with denser regions of gas. This allows the most energetic particles to escape the confines of the Guitar Nebula and fly to the right of the pulsar, creating the filament of X-rays. When those particles escape, they spiral around and flow along magnetic field lines in the interstellar medium, that is, the space in between stars.

The new movie shows the pulsar and the filament flying towards the upper left of the image through Chandra data taken in 2000, 2006, 2012 and 2021. The movie has the same optical image in each frame, so it does not show changes in parts of the “guitar.” A separate movie obtained with data from NASA’s Hubble Space Telescope (obtained in 1994, 2001, 2006, and 2021) shows the motion of the pulsar and the smaller structures around it.

Hubble Space Telescope data: 1994, 2001, 2006, and 2021.
X-ray: NASA/CXC/Stanford Univ./M. de Vries et al.; Optical full field: Palomar Obs./Caltech & inset: NASA/ESA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare)

A study of this data has concluded that the variations that drive the formation of bubbles in the hydrogen nebula, which forms the outline of the guitar, also control changes in how many particles escape to the right of the pulsar, causing subtle brightening and fading of the X-ray filament, like a cosmic blow torch shooting from the tip of the guitar.

The structure of the filament teaches astronomers about how electrons and positrons travel through the interstellar medium. It also provides an example of how this process is injecting electrons and positrons into the interstellar medium.

A paper describing these results was published in The Astrophysical Journal and is available here.

NASA’s Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.

Read more from NASA’s Chandra X-ray Observatory.

Learn more about the Chandra X-ray Observatory and its mission here:

https://www.nasa.gov/chandra

https://chandra.si.edu

Visual Description:

This release features two short videos and a labeled composite image, all featuring what can be described as a giant flame-throwing guitar floating in space.

In both the six second multiwavelength Guitar Nebula timelapse video and the composite image, the guitar shape appears at our lower left, with the neck of the instrument pointing toward our upper left. The guitar shape is ghostly and translucent, resembling a wispy cloud on a dark night. At the end of the neck, the guitar’s headstock comes to a sharp point that lands on a bright white dot. This dot is a pulsar, and the guitar shape is a hydrogen nebula. The nebula was formed when particles being ejected by the pulsar produced a cloud of bubbles. The bubbles were then blown into a curvy guitar shape by a steady wind. The guitar shape is undeniable, and is traced by a thin white line in the labeled composite image.

The pulsar, known as PSR B2224+65, has also released a long filament of energetic matter and antimatter particles approximately 12 trillion miles long. In both the composite image and the six second video, this energetic, X-ray blast shoots from the bright white dot at the tip of the guitar’s headstock, all the way out to our upper righthand corner. In the still image, the blast resembles a streak of red dots, most of which fall in a straight, densely packed line. The six second video features four separate images of the phenomenon, created with Chandra data gathered in 2000, 2006, 2012, and 2021. When shown in sequence, the density of the X-ray blast filament appears to fluctuate.

A 12 second video is also included in this release. It features four images that focus on the headstock of the guitar shape. These images were captured by the Hubble Space Telescope in 1994, 2001, 2006, and 2021. When played in sequence, the images show the headstock shape expanding. A study of this data has concluded that the variations that drive the formation of bubbles in the hydrogen nebula also control changes in the pulsar’s blast filament. Meaning the same phenomenon that created the cosmic guitar also created the cosmic blowtorch shooting from the headstock.

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