Starship Asterisk*

When Mars met Neptune

Explanation: On January 1, a Mars-assisted viewing opportunity allowed binocular-equipped skygazers to cross an ice giant off their life list. Remarkably, the line-of-sight to the bright Red Planet could guide you to within 0.02 degrees of a faint, pale Neptune in Earth's night skies. Taken within 3 hours of their closest conjunction, these panels capture the odd couple's appearance in skies over Brisbane, Australia. A wide field view includes the new year's slender crescent moon near the western horizon and Venus as the brilliant evening star. Mars and Neptune are indicated at the upper right. The two inset magnified views were taken with the same telephoto lens and so do show the Mars-Neptune conjunction and the apparent size of the crescent moon at the same scale. This week Neptune hangs out near Venus on the western sky.

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I love the color contrast between Mars and Neptune!

Ann

When Galileo was first observing Jupiter, and thought the four moons were stars, Uranus was coincidentally nearby and I think appears in one or more of Galileo's drawings as a star. After some weeks Galileo figured out that those four "stars" were satellites, but he did not twig to Uranus.

heehaw wrote:
When Galileo was first observing Jupiter, and thought the four moons were stars, Uranus was coincidentally nearby and I think appears in one or more of Galileo's drawings as a star. After some weeks Galileo figured out that those four "stars" were satellites, but he did not twig to Uranus.

Galileo saw Neptune not Uranus.

(Galileo would have created a slight breach of etiquette by skipping Uranus and going right for Neptune.)

Darn, I would have liked to see this. Wish I had known.

Stan wrote:
Darn, I would have liked to see this. Wish I had known.

• I'll have what he's having.

Stan wrote:Darn, I would have liked to see this. Wish I had known.

Over the years, I've found this Sky & Telescope site quite helpful. Scrolling down through the observing articles you'll find the Mars Meets Neptune post.

Stan wrote:Darn, I would have liked to see this. Wish I had known.

Yeah, me too.
Next one I can see in a chart that looks good is:
December 7, 2018 14:55:51 UTC Mars 2' south of Neptune at 88.3° East

Don't you just love the language of the occult? Why is the hidden so much more a part of our fascination than what's obvious. Especially when it's just for an IOTA of time. Opposing, I suppose it'll be a while before Mars will actually hide Neptune. That's another mystery.

Fred the Cat wrote:I suppose it'll be a while before Mars will actually hide Neptune. That's another mystery.

It's certainly a rare event, so yeah it will be a while. Except for year 2100, the 2017 and 2018 conjunctions are the closest through 2200.

1. Mars occulted Neptune on Aug 25,1278. Their separation was ~0 arcseconds and the event lasted around 20 seconds
2. On Aug 23, 2100, their separation will be 8 arcseconds. Given their diameters will be 3.6" (Mars) and 2.2" (Neptune), their limb separation well be ~6 arcseconds

alter-ego wrote:
Mars occulted Neptune on Aug 25,1278.

Their separation was ~0 arcseconds and the event lasted around 20 seconds

Darn, I would have liked to see this. Wish I had known.