The enormous, 25-meter Giant Magellan Telescope (GMT) will not only usher in a new era in ground-based astronomy, but will take the first cutting-edge images of the Universe where stars are seen exactly as they actually are: without diffraction spikes. (Giant Magellan Telescope — GMTO Corporation)

World’s Largest Telescope To Finally See Stars Without Artificial Spikes

One of astronomy’s most iconic sights in an artifact of faulty optics. Here’s how a new, great design will overcome it.

When you look out at the greatest images of the Universe, there are a few sights that light up our memories and fire our imaginations. We can see the planets in our own Solar System to incredible detail, galaxies lying millions or even billions of light years away, nebulae where new stars are being birthed, and stellar remnants that give an eerie, fatalistic look into our cosmic past and our own Solar System’s future. But the most common sight of all are stars, lying everywhere and in any direction we care to look, both in our own Milky Way and beyond. From ground-based telescopes to Hubble, stars almost always come with spikes on them: an image artifact due to how telescopes are constructed. As we prepare for the next generation of telescopes, however, one of them — the 25-meter Giant Magellan Telescope — stands out: it’s the only one that won’t have those artificial spikes.

Hickson compact group 31, as imaged by Hubble, is a spectacular “constellation”, but almost as prominent are the few stars from our own galaxy visible, noted by the diffraction spikes. In only one case, that of the GMT, will those spikes be absent. (ASA, ESA, S. Gallagher (The University of Western Ontario), and J. English (University of Manitoba))