A remarkable image from a camera the size of a planet
The image of Sagittarius A*, the supermassive black hole at the centre of the our Galaxy, produced using the Event Horizon Telescope, is astounding. Five years in the making, and taken with a ‘camera’ the size of Earth; it’s the result of collaboration between 80 institutions and more than 300 scientists. It is the first direct visual proof that our theories are correct, and there really is an immense gravitational engine driving our Galaxy. Astronomy writer Jane Green explores the story behind the image.
Sagittarius A* may be out of reach for us amateur astronomers, but the summer skies are full of deep-sky targets for observers and imagers with telescopes – even from towns and cities, if you know where to look. Someone who does is American amateur astronomer Rod Mollise, and in From City Lights to Deep Space he continues his series with 21 summer deep-sky targets, all visible with some degree of skyglow.
You’ll want to observe these deep-sky delights at the start and end of July, avoiding the week or so around the 13th, when it’s full Moon and bright moonlight will wash the sky. This full Moon is a noteworthy one, though – the largest perigee full Moon of the year and so the closest to Earth. While this only increases its apparent size by a few arcminutes, what will make far more of an impression is the Moon illusion, that powerful trick of the eye when the Moon is close to the horizon and appears much bigger than normal.
Moonrise is at 21:11 BST on the 13th – do look out for it.
Enjoy the issue!
PS Our next issue goes on sale on Thursday 14 July.