“Hand Of God” Fancied In X-ray Glow Of Pulsar Wind Nebula

The pattern of an open hand is easy to imagine in this recent X-ray photo of a supernova’s cloudy remains. The structure radiating high-energy X-rays is shown in blue. Lower-energy X-ray light previously detected by NASA’s Chandra X-ray Observatory is shown in green and red. Click to enlarge. Credit: NASA/JPL-Caltech/McGill

A new X-ray photo taken by NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) showing a cloud of ejected material from a former supernova shows an eerie shape reminiscent of a hand reaching into space. A thumb of glowing gas extends from the palm; higher up, ghostly fingers touch a speckled red haze. Nicknamed the “Hand of God” it’s the remnant debris cloud from a long-ago exploding star.

Model of a pulsar, a tiny, rapidly rotating star that’s had its electrons and protons crunched together into pure neutrons during the core collapse in a supernova explosion. Beams of electromagnetic radiation and particles shoot out from the star’s poles as it rotates. Credit: NASA

Buried within lies the pulsar PSR B1509-58, itself a remnant of the supernova.This superdense, city-sized star spins around seven times a second and fires a wind of particles and radiation into the cloud. As they interact with the magnetic fields threading the supernova’s dregs, X-rays are released causing the cloud to glow.

A pulsar is the rapidly rotating neutron star that beams a pulse of radiation like a lighthouse during every spin. It’s what remains of a supergiant star’s core after it collapses and compacts in the wake of a supernova explosion. Almost all the empty space between and within atoms is squeezed out as electrons and protons are crushed into neutrons.

Not only are neutron stars fantastically dense – all the people of the Earth would fit in one teaspoon of pulsar star matter – but incredibly small. Pulsars pack at least one to three sun’s worth of material into a sphere some 6-15 miles (10-25 km) across.

When the pulsar’s beam sweeps in Earth’s direction we see a quick blip of light. The fastest spinning pulsar, named PSR J1748-2446ad, revolves at 716 times per second! Credit: W. Kramer

The pulsar is located inside the bright white spot and can’t be seen in the photo, but it’s energetic interaction with the remaining supernova gases creates the hand-shaped nebula. The red cloud at the end of the finger region is a different structure, called RCW 89. Astronomers think the pulsar’s wind is heating the cloud, causing it to glow with lower-energy X-ray light. One of the unanswered questions is whether the pulsar’s emissions light up the cloud in the shape of a hand or whether the cloud really has a natural hand shape.

Terms like “God particle” and “Hand of God” are great ways of making a human connection to cosmic wonders, but I’ll admit I cringe a little whenever I hear them because they might imply a supernatural explanation when there’s a perfectly natural one at hand.

Left image is normal while the right side of the right image has been darkened using the “hand of God” burning technique in Photoshop. Credit: Bob King

Funny. Back in the darkroom days when we used enlargers to project a negative image on a sheet of photo-sensitive paper and then dipped the sheets into developer to watch the images magically appear, “Hand of God” had an entirely different meaning.

We’d often darken the bright borders of our photographs so they’d look better in the newspaper by creating a small aperture with our fist under the enlarger lens.  Light pouring through the hole would be directed to this or that area of paper like a flashlight to darken or “burn it in”. We called it “hand of God” burning because it was artificial – not in the original photo – and sometimes used or misused to overpowering effect.

However you see the wonder of the universe from darkroom to pulsar winds, may it always buoy your spirits.

4 Responses

    1. astrobob

      One reader suggested it would be better named “The Hand of Homer” after the Simpsons character.

Comments are closed.