Posts Tagged ‘jupiter’

Venus, Jupiter and the Moon, Cosmic Ballet in February and March 2012.

February 21, 2012

For those who have been paying attention to the sky over the past few months, you will have seen Venus crawl out of the evening twilight, and Jupiter sink towards it.  These two VERY naked eye planets (both outshine even the brightest stars) are now only about 15 degrees apart (about the spread of your fingers held out at arms length), with that value set to shrink to about 3 degrees over the next 3 weeks.  Get the popcorn is ‘cos its gonna be a fantastic show!

The ballet is highlighted in the sequence below.

Venus Jupiter conjunction of 2012 (click to enlarge)

A) t= 0.  Jupiter and Venus hang in the evening sky.  Venus, by far the brighter of the two lies below Jupiter, and the pair are separated by about 15 degrees.  For reference, the Moon and Sun are about half a degree in diameter, and your outstretched fingers at arms length are about 15 degrees in angular size.

B) t= 5days.  The moons orbit takes it out of the solar glare and by the 26th it resides between Venus and Jupiter.  This will be a spectacular sight for those who get to see it, with the 2nd, 3rd and 4th brightest objects so close together in the sky.  The angular distance between the two planets has now closed to about 10 degrees.  Most of this apparent motion of Jupiter is due to the Earth moving around the Sun, while with Venus, about half of the apparent motion comes from this planet orbiting the Sun.

C) t~21 days. The Venus, Jupiter conjunction of 2012.  The two most spectacularly bright planets appear at their closest  (~3 degrees).

D) t~33days.  The Moon has now made a complete orbit since it last visited these planets.  When it last did, Jupiter was the higher, and Venus the lower.  The second time the moon visits these planets the order is reversed!  Venus the beguiling bright is now the higher of the two objects!  The objects are again separated by about 10 degrees.

For those who want to see what this looks like in animation form, take a look!  Download the  free solar system visualization software Celestia (http://www.shatters.net/celestia/)

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A Night looking at Uranus!

August 24, 2011

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.

Movement of Uranus vs 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)

So it was that I set out with my scope on the evening of 22nd 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!

Watching Sunset on the Moon, and things that go bump in the night!

August 20, 2011

Well it’s a start.  Sunset on the Moon!

This is the time lapse of sunset on the moon, taken at prime focus with a cpc11 with a focal reducer and a canon 60D.  The conditions were less than perfect.  This was about 9 hrs all in, and really quite an infuriating 9 hrs.

Firstly, since my ‘run in’ with the mountain lion, I’ve become VERY twitchy about things that go bump in the night, and would periodically scan the torch around, looking for ‘eyes’.  There was also an amusing part when a piece of paper blew out of the car.  The ‘sudden noise’ in the dark elicited an immediate reaction from me, which to the impartial observer must have appeared quite funny and disproportionate! (twirling around ready to attack the piece of paper…… hmmmm….  time to switch to decaf!)

Not all bad though, amazing what the heightened senses can find!


For some reason the telescope is lousy at tracking the moon.  I think this is to do with the fact that the Earth axis, and the normal of the orbit of the moon are out by about 6 degrees.  Practically what this means is the moon not only moves at a different rate to the stars (that is it goes around the sky in about 25 hours, not 24 like pretty much everything else).  But even with lunar rate, the tracking is poor.  I think the moon is also moving up/ down due to the difference in the normal of the Earth rotation and the moons orbit, and the mount is not smart enough to work this out.  The practical upshot of which is the moon will drift out of the field of view over a period of about an hour, so I had to set the alarm to go off every 20 minutes throughout the night in order to recenter the moon.

Further recentering the frames, taken every 2 minutes in editing is also a pain in the ass.  Thankfully Sony Vegas now has a ‘motion stabilizer’ feature that takes a lot of the donkey work out of this.

This is the finished product!  Well actually, only part of it.  At prime focus the telescope can get the best part of the moon in the frame.  I just selected one crater, as it shows the shadows nicely.

Tracking on everything else is perfect, in that at the end of the evening I dialed up Jupiter, and it went straight to it.  Cute! Never seen Jupiter by the full light of day before!

The Solar System in Perspective!

August 10, 2011

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.

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!.

Movement of Uranus vs 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)

Wedneday 27th July (It’s like sex!)

July 28, 2011

It was a disheveled piece of human flotsam that crawled out of the mountains that morning.  I had spent a night fighting a losing battle again sleep, and had, in terms of results, very little to show for it.  I know I thought to myself, look the night might have been one long concatenated mess, but at least I can haul my carcuss down to town and get a thousand calorie breakfast from mcdonalds, and Im sure you will start to get a grip once you have  a full stomach.  Regrettably, by the time I got down to town Mcdonalds had JUST finished breakfast.  The moment was a cross between ‘Falling Down’ and that moment in ‘Evil Dead, Army of Darkness’ in the alternative ending where he oversleeps.  Oh yeah it was one of those ‘the world conspires against me’ type moments.  After a long deep sigh, the eyes snap open with regained focus: time to go on the offense!  Online I soon discovered that the reason the Orion Deepspace Video camera wasn’t working up to expectation is it has an integration function in the menus!  I laughed, when all else fails: READ THE INSTRUCTIONS.  Spent a few hours rendering and uploading what I had.  Now the next problem, that damn screw!  I need a replacement for that damn screw.  Turns out Ridgecrest has a Home Depot, and I figured that was the logical place to try for a bizarre screw.  I was wrong- they had nothing!  Arse, thousands of bux worth of telescope crippled by a tiny screw.  Then it dawned on me, I could just drill and tap a hole myself for any screw I wanted.  Deep in my mind there was a spark, I had a drill and tap and a load of screws that would fit in the car, they were part of the stuff for the airplanes.

Picked up some supplies and headed back up into the mountains, same place at last night.  This time I was more seasoned on that grinding hill though and got up all the way without even a hint of overheating.

Up at the top of mountains, I sorted out firstly the backend of the telescope,

Then the webcam.

Come the test of first light, both performed admirably.  The sky wasn’t still enough for planets, but it was wonderfully clear.

The Deepsky video camera worked as expected! (~500 bux) 🙂

The stripped MS webcam worked admirably (~50 bux) 🙂

The video of the planets shot on by eyepiece projection onto the sensor of the D60 (~900 bux) was okay, but not as good as channeling it straight into a video camera.

The 60d I have to admit is a heinous machine for astro!  I got it primarily as I needed 2 DSLRS to do some of the projects I want to get done on this trip, to work with the 40D.  The 60D just idles circles around the 40D.  I think a lot of it is simply a better sensor.  More pixels, if they are not being used for resolution, mean faster light gathering, and lower noise.  The bottom line is the 60D goes up to iso ~6000, at least 2x what the 40D will do.  The 60D will also do video, which I thought might be useful, although thus far it hasn’t panned out, although this might just be teething troubles with the camera.  Just for an example, crank the ISO up to about 5000 and do a 1min exposure (unguided, bar the telescope tracking) on M51, and this is what you get:

M51, The Whirlpool Galaxy

M51, The Whirlpool Galaxy, 1min exposure, iso 5000, canon 60d

After that, all you need is an intervalometer and deepskystacker.  In many ways it’s such a cheat.  When I was young, I improvised all sorts of devices for the tracking, and there was none of this ‘cap a test frame to see if it’s centered’.  You took the pictures, and after minutes of painstaking guiding, you had to wait till at least the next day to see how well you did when you got the film processed.  Many a time I chuckle at night as to how what used to be hours of work, and a day or two to see the results from can now be effortlessly superseeded by a minute of scope time.

Later in the night, after visiting many a deep sky object, I turned the scope to Jupiter, then Mars, then the very late moon, all using the same magnification, just so I could give folks the scale of these things, all on the same magnfication.  The seeing was abysmal!  Mars was a swimming ball!  However all on the same magnification I got Saturn, Jupiter, Mars and the moon!

 

So yeah, I guess its like sex, in the dark, the first time is always a fumbled and inept experience.  However, having seen things in the broad light of day, and having had time to ponder on what went wrong and why, the second time can be more of the ‘tour de force!’ 🙂

Monday 25th July (WHOLE SKY time lapse!)

July 26, 2011

Monday 25th July, up after dawn and rolled into LA.  Traffic is a nightmare!  Picked up the fixed camcorder by 9ish and headed over to a mcdonalds for wifi.    Caught up with blog n emails.  Notably I’ve now got a buddy in Hawaii who’s ready to give the global timelapse thing a go.  He sounds like he really knows what he’s doing and certainly has much better kit than me.  However I still needed a location to head to.  I checked out the clear sky forecasts and they were excellent in the Sierra Nevada valley.  Packup up and headed out, charging batteries on the way.  This is always the absolute nightmare of astro-on-the-road is when you are spending so much time out of doors in the hard sunlight, your body really syncs up with the sun in a powerful way.  Almost to the point where, sun goes down and you go to sleep, and yeah it’s REALLY hard to fight against that to stay up all night doing stuff.  On the way out of LA I stopped by and saw Lisa, who had lent me a couch during TAM.  Then the drive out to the North.   Again the traffic was a nightmare.  Got to Ridgecrest in late afternoon passing enroute something that looked like an observatory, but I now believe to be military radar of some sort.  It looks a good site.  Lots of roads leading off into the desert near the top of a mountain, purportedly for dirt bikers, but whatever, looked like my polite surburban 2wd low clearance could handle it.  Picked up the largest coffee I could find, and headed out into the desert.  In the end I hardly had to go that far off the road and was there for a fantastically dark sunset.  However there was wind, 10-20 mph wind.  Firstly thats the kiss of death if you are trying to point a telescope at a point source, and secondly there was a small amount of dust with it.  Now that was great for the lasers, meant you could see them easily, however its a killer for shutter mechanisms, drives gears etc.  I decided I would stand off on setting up the scope till the wind died down.  The wind didn’t die down, not even a little.  However the sky was superb with the milky way forming a glowing arch from horizon to horizon.  Started messing around with the cameras.  Even if I can’t do any astro, I’ve got some stuff to field test.  Most notably the 4mm ‘180 degree lens’.  Gave good piccies of the Milkyway and after a while I decided to laser my name into a mountain, just for yuks.  After that, I spent a wonderfully pleasant night, with the cool desert wind blowing steadily through my car, all the time with my head poked out of the window, watching the stars slowly spin above my head.  Jupiter rose fast and high, and the late cresent moon somewhat after it.  The next morning I was quite happy with the results!