A Night looking at Uranus!

Uranus is frequently overlooked and for many reasons.  Firstly, lets just say its name hasn’t phonetically aged well.  Secondly it’s small and faint, barely visible to the naked eye, and even the most powerful telescopes show little more than a tiny featureless grey-green disk.

Most powerful telescopes will show the five main moons of Uranus, Miranda, Ariel, Umbriel, Titania and Oberon.  The innermost of these Miranda, has, if memory serves the highest cliffs in the solar system (due to being previously (presumably) smashed by an impact) and has an orbital period of about 1.5 days.  That means you should be able to easily see its movement over the period of a night.

Now I had tried this previously, and had been surprised that the planets movement was comparable to the movement of its moons, but that night had been scuppered by a flat battery.

The stars in the background are fixed. The two picture of Uranus are taken a few hours apart, and while the moons (relatively close to the planet) don't move much, the planet conspicuously moves against the background stars!) (click to enlarge)

So it was that I set out with my scope on the evening of 22^nd Aug 2011 to see what could be captured.  I decided to head up to an observatory site that had previously seemed good up near the top of the somewhat active volcano, Lassen Peak.  The site is high, almost 2 miles up, but the seeing was less than perfect (a very constant ~ 5mile an hour wind, which was probably a blessing in that it bought warmer air from somewhere, but was also a curse due to the wind chill- I was surrounded by snow fields!).

Nonetheless, at prime focus of the 11in CPC1100 with ~1000 iso and 4 second exposure on a canon 60D seemed to bring out easily at least 4 of the moons of Uranus.

After that, I just had to maintain the kit for 8 or so hour.  A pain in the ass, as there were several pieces of kit that all need to work or the night would be ‘lost’.  So you basically have to periodically check all the batteries on the various time lapse and tracking kit are working functionally.  The bottom line is you can actually get quite a lot of sleep, but its horribly disjointed. The practical upshot of which was the next day I was wiped out to the point where I had actually planned to head up into Oregon to do something, but for the first time ever on a road trip I did something I’d never countenanced before.  I stayed a night in a motel!!  First time in 5 years!  A motel 6 I should add!  All I wanted was somewhere where I could get a shower, a bed for the night, and damn, just sit back for a moment, put my feet up, and have a glass of wine……ahhhhhh.

I was REALLY happy when I processed this, not really for what I had hoped to achieve, which was to get the motion of the moons, as while it was visible, it wasn’t that great.  But what was great was the motion of the whole Uranus system against the background stars.  I knew this MIGHT be visible, but I really didn’t expect it to looks as cool as it did!  Now it should be said that most of the motion you see here is probably not due to the motion of Uranus, but due to the motion of the Earth.  Nonetheless, its still really cool!

The finished results!

The Solar System in Perspective!

The Moon, the Jovian (jupiter) system, and the Uranus system, all on the same scale (all photographed prime focus through an 11in f6.3 SCT) aug 10th 2011.

The moon, Jupiter and moons, and Uranus and moons, all to scale. Click to enlarge.

It’s all part of a larger project I’ve been working on of trying to get time-lapse of various extra-terrestrial bodies.

The real problem is the Earth is just spinning too bloody fast!  Damn, there’s a reason why all those new telescopes are going out there in the Legrange points!

Initially I was having all sorts of trouble tracking the moon!  Hmm that just shouldn’t be, it tracks everything else in the sky just fine.  Then of course, the obvious dawns on me:- it’s tracking the stars and not the moon!  The moon goes around the sky an extra time every 28 days! Thats about 12 degrees a day, or half a degree an hour!  Given that the moons only about half a degree in diameter, no wonder it kept drifting out of the field!  Okay, so I got intermediate time-lapse of the moon, that shows the project is possible.  A failure, sure, but a very instructive failure.

After the moon I took some caps of Jupiter and moons, and Uranus and moons, great for putting them all into perspective.  Then it dawns on me, that it might be possible to do a timelapse of Uranus’s moons too, that’d be really cool.  So I set up the scope to take pictures every 5 minutes.  The results weren’t that impressive (well it only ran for a few hours before dawn), but more interestingly is that you can actually see uranus move against the background stars over this period.  It really threw me, because I was trying to line up the background stars, and it just wasn’t possible, then the obvious came to mind.  Duhh, Uranus is moving!  So yeah, inadvertently I’ve now found that you can watch the planets move in real time!  Probably works best on the faint ones, like Uranus, as you can see more background stars!.

The stars in the background are fixed. The two picture of Uranus are taken a few hours apart, and while the moons (relatively close to the planet) don't move much, the planet conspicuously moves against the background stars!) (click to enlarge)