It resembles a stairway to heaven. In fact, it is a series of steps in the death of a distant star. Using the Hubble space telescope, astronomers in Europe have peered across 2 300 light years of space to examine the strange structure of HD44179, sometimes called the Red Rectangle.
The star takes its name from the unique shape and colour seen from ground-based telescopes. It is similar to the sun, but far older, and now in its death throes.
HD44179 started firing off its outer layers about 14 000 years ago. In a few thousand years, it will become smaller and hotter, releasing cascades of ultraviolet light into its own nebula, the cloud of gas and dust around it.
”The structures that impress me most look like the rungs of a ladder, although they are actually projections of gas cones, like a series of nested wine glasses filled to their brim with gas and seen from the side,” said Hans van Winckel, of the Catholic University of Leuven, Belgium, who reports with colleagues in the Astronomical Journal.
Although other telescopes show the object as a rectangle, the Hubble photographs reveal an x-shape, probably from outflows of gas and dust from the centre. The cone-shaped discharges in opposite directions are linked by puzzling structures that look like the rungs of a ladder, or strands of a spider’s web.
These might represent eruptions, separated by periods of relative quiet — HD44179 could be a pair of stars, orbiting each other and ripping huge quantities of material from each other.
It was first spotted more than 30 years ago, when an infrared telescope was launched aboard a rocket for one quick preliminary survey.
Astronomers are interested because Earth, and its living creatures, are recycled from the rubble of heavy elements, hydrocarbons and complex molecules shot from some long-vanished dying star. — Â