And what would that be?<\/p>\n
First\u00a0predicted<\/a>\u00a0in the 1980s, Mercury’s tail was\u00a0discovered<\/a>\u00a0in 2001. Its source is\u00a0Mercury’s super-thin atmosphere<\/a>. Mercury is so close to the sun, pressure from sunlight itself can push atoms out of the atmosphere and into space. The escaping gas forms a tail more than 24\u00a0million<\/em>\u00a0km long.<\/p>\n
The tail is rich in sodium–a substance sputtered from Mercury’s surface by solar wind and micrometeorite impacts. That’s why [Dr. Sebastian] Voltmer’s yellow sodium filter did such a good job revealing the gaseous stream. [spaceweather.com<\/strong><\/a>]<\/em><\/p><\/blockquote>\n
There’s a lovely backyard picture of it at the above link, but I shan’t steal it.<\/p>\n
It makes sense, of course, but that with the addition of a yellow filter your telescope can see it caught me by surprise. And pleases me.<\/p>\n","protected":false},"excerpt":{"rendered":"
And what would that be? First\u00a0predicted\u00a0in the 1980s, Mercury’s tail was\u00a0discovered\u00a0in 2001. Its source is\u00a0Mercury’s super-thin atmosphere. Mercury is so close to the sun, pressure from sunlight itself can push atoms out of the atmosphere and into space. The escaping gas forms a tail more than 24\u00a0million\u00a0km long. The tail \u2026 Continue reading