Video: Take a Spin Through the Pencil Nebula
Eleven-thousand years ago a star exploded, sending a wispy witch's broomstick flying across the southern sky.
When it comes to enduring legacies, supernovae have little competition in the universe. What you are looking at above is the Pencil Nebula (though its appearance is sometimes compared to a witch’s broomstick) as captured in a new image by the Wide Field Imager at the European Southern Observatory’s La Silla Observatory in Chile. From our vantage point on Earth, it is still noticeably moving across the night sky even though it is something like 8,000 light-years away. All this from a star that exploded 11,000 years ago.
The linear glowing portion of the nebula above (the part that gives it its name) is the brightest part of a huge shell of gas produced when a dying star exploded in the southern constellation of Vela, sending a massive shockwave hurtling across the region. That shockwave heated gas and dust in the region as it pushed its way through space, first to millions of degrees and then to varying temperatures as the shockwave lost momentum. It also spawned the beautiful filaments of nebulosity that appear to trail from the pencil itself. The blue regions are populated largely by ionized oxygen, while red indicates cooler emissions from clusters of hydrogen.
The pencil nebula measures roughly three-quarters of a light year across and is still moving so fast–roughly 400,000 miles per hour–that even at its vast distance from Earth it will visibly change positions in the sky over the course of a human lifetime, even though the explosion that first set the whole thing in motion occurred long before the first human lives were recorded by history. Take a flight through it yourself below.