Archive for the ‘Planet’ Category

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Observing Report: PVAA star party on Mount Baldy

April 22, 2015

PVAA Mt Baldy Star Party 2015-04-15 panorama

Last Saturday a bunch of us from the Pomona Valley Amateur Astronomers, plus a few folks from neighboring clubs, got together at Cow Canyon Saddle on Mount Baldy for the monthly PVAA star party. Here’s a panorama of the whole group while we were setting up before sunset. It’s worth clicking on to scan around the full-size image. I wasn’t holding a camera on a tilt, the parking lot really does slope down significantly from northeast (right) to southwest (left).

PVAA Mt Baldy Star Party 2015-04-15 west end group

I spent most of the early evening with these folks at the southwest end of things. From left to right here we have Cori Charles, our local outreach coordinator for the Planetary Society; my son, London, with his XT4.5; Gary Thompson, our club treasurer – his powder-blue 8-in Dob is mostly hidden behind London; Rob Record of the Riverside Astronomical Society with his C6 SCT; and Terry Nakazono with his StarBlast 4.5EQ. My Celestron C80ED is in the right foreground, and with Venus in the photo near the bottom of this post.

PVAA Mt Baldy Star Party 2015-04-15 Kassandra and Kevin Garcia

Here are Kassandra and Kevin Garcia with their 8-inch SCT – they treated all of us to a steady stream of wonderful views.

I didn’t get pictures of everyone and their scopes. People I missed included Bill Maxey and his Vixen VMC 200L, Brandon Finnegan and his XT8, Frank Nelson, some folks who came while I was out and brought a Celestron FirstScope, and possibly others. And I haven’t mentioned Ed Grobel and Patty Morrison yet…

PVAA Mt Baldy Star Party 2015-04-15 Patty Morrison

Ed and Patty are relatively new to amateur astronomy and to the club, but they are getting up to speed very fast. Here’s Patty looking at Jupiter through their Celestron NexStar 6 Evolution. Yes, that’s a bunny ear you can see on her hat. Ed was wearing a chicken hat, I think. I’m going to ask Patty to make me a dinosaur hat.

Anyway, in the early part of the evening I split my time between socializing, looking through other people’s scopes, and helping London with a few things, although he is pretty independent with the XT4.5. He found the Orion Nebula, the Pleiades, and the Beehive (M44) all by himself, and the open cluster M41 and the galaxy pair M81/M82 with just a little help from me. I also got nice views of Jupiter through several scopes, and Brandon Finnegan treated me to great views of the Sombrero Galaxy (M104) and the triple star Beta Monoceros in his XT8.

At around 10:00 I left to run London home, but I was back on the mountain by 11:00. After that, my own scope sat mostly neglected while I cadged looks off everyone else. I spent a lot of time, close to four hours, observing with Ed and Patty and their C6. I probably missed a few things, but a mostly-complete list of objects we looked at includes Comet Lovejoy – still surprisingly bright as it heads north out of the solar system – Jupiter, Saturn, M13, M5, M57, M81/M82, NGC 6543, the Leo Triplet, Epsilon Lyrae, Albireo, Polaris, M51 and NGC 5195, M4, M27, Brocchi’s Coathanger (in the finderscope of the XT4.5), Saturn again, Jupiter again, NGC 4565, and Saturn yet again to conclude.

PVAA Mt Baldy Star Party 2015-04-15 C80ED and Venus

For me, the best views of the night were of globular clusters and Saturn. There was a stretch around 11:30 when most of us still on the field went a little glob-mad. I looked at M13 through both of the C6 SCTs and through Gary’s 8-inch Dob. I was extremely impressed by the 6-inch SCTs. They gave up surprisingly little to the Dob in terms of image brightness and their long focal lengths and comparatively high magnifications meant that everything we looked at had a nice image scale. All of the globs we looked at in Ed’s and Patty’s scope had nicely resolved outer halos, and NGC 6543, the Cat’s Eye Nebula, was distinctly bluish-green in the eyepiece.

Then there was Saturn. Seeing was very good Saturday night and Saturn was just stunning. I have never been able to hold the Cassini Division in direct vision for so long at a time. Occasionally a random gust or roil would smear it out but it was easily visible at least 80% of the time. The disk of the planet showed salmon-colored bands, and we could make out the shadows of the rings on the planet, and of the planet on the rings, so dark and crisp they looked inked in. That’s why we kept going back for more.

After Ed and Patty packed up about 3:00 AM, I wussed out and crawled in the Mazda for a couple of hours of sleep. I had a couple of quick peeks with the XT4.5 after I got up, but by then the sky was starting to get bright. Terry had pushed right through with only a half hour catnap earlier in the evening, adding 7 or 8 new objects to his tally, which now includes over 1000 unique deep-sky objects. We packed up and went down the hill for breakfast. All in all, a great time.

Before the star party, someone wrote to Gary to ask if non-members are welcome at PVAA star parties. The answer is yes, always! If you are within striking distance, come on out and see some things with us. Our star party calendar and directions are available on the PVAA website, http://pvaa.us/. I hope to see you out there.

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Chasing Comet Lovejoy

February 4, 2015

I’ve been out a few times in the last few weeks, mostly to see comet 2014 Q2/Lovejoy. It’s still nice and bright and it’s an easy catch in binoculars. You can get up-to-date finder charts from Heavens Above.

Our notes from January 17 - Steve's sketch of Jupiter and my sketches of the Trapezium and comet Lovejoy.

Our notes from January 17 – Steve’s sketch of Jupiter and my sketches of the Trapezium and comet Lovejoy.

About three weeks ago now, on January 17, I was up at the Webb Schools observatory with Steve Sittig, who you’ll recall from the virtual star party, last summer’s birthday observing run, and – farther back, in 2010 – comet 103P/Hartley. We were using the equatorially mounted C14 in the Webb Schools’ Hefner Observatory. We started on Orion just to get warmed up, and we could easily see the E and F stars in the Trapezium. After that we went after the comet. It was kind of a comedy of errors. We had problems getting the telescope pointed where we needed it, and neither of us had seen the comet yet so we were a little unsure of where to look. Finally we started scanning around with binoculars and then the comet was an easy catch, and we were able to get the scope on target. I made a couple of sketches a few minutes apart that show the comet moving through the field, but the western sky was getting hazy and pretty soon the comet was lost to us.

Jupiter from Webb - Jan 17 2015 - with labels

Jupiter and the four Galilean moons on January 17, 2015. Click through to see the moons. Photo by Steve Sittig.

After that we turned east to have a look at Jupiter. Steve made a sketch and got some photos with his DSLR mounted to the C14. As is usually the case, the photos do not nearly capture all of the detail that we could see at the eyepiece. We could see many cloud bands at high latitudes, and north and south equatorial belts were highly detailed with ruffled edges and festoons. Io was distinctly yellow at the eyepiece, much more so than the other moons, which ranged from white to a very faint blue. Thanks to Steve for the photos and for the great, if brief, night of stargazing.

Comet Lovejoy 2015-01-24 invert

The next Saturday, January 24, London and I set up telescopes in the driveway and took in some of the best and brightest objects (most of which London found himself!). I sketched the comet a couple of times, to show it moving against the background starfield.

I have another long-delayed observing report, from a trip to Anza-Borrego Desert State Park late last fall, but that will have to wait for another time.

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Earth-moon distance and the diameters of the planets

June 15, 2014

A few days ago Mike sent me this:

Earth-moon distance and planetary diameters

I was surprised to see so many people calling BS on this–it’s simple enough to double-check. So I did. Here are the results.

Mean radii in km, from Wikipedia:

  • Mercury – 2400
  • Venus – 6100
  • Mars – 3400
  • Jupiter – 69,900
  • Saturn – 58,200
  • Uranus – 25,400
  • Neptune – 24,600
  • Total – 190,000

Doubled, to convert to diameters – 380,000 km

Average Earth-moon distance, also from Wikipedia: 384,000 km.

Yep, this checks out. With the proviso that the Earth-moon distance actually varies from 363,000 to 405,000 km, so sometimes you’d have to leave out Mars and Venus, and other times you’d have to clone them to fill the extra space.

If you want a remarkable coincidence, the moon formed maybe only 10,000 miles from Earth and has been gradually receding ever since. So we are living in the tiny slice of Earth history when the moon is at just the right distance to appear the same relative size as the sun, and thus produce total eclipses as we know them. Annular eclipses have only been around for a few tens of millions of years, and in another few tens of millions of years, they’re all we’ll ever get, because the moon will be too distant to completely block the sun.

Anyway, after I sent Mike this reply, he said, “That is a whole lot of awesome, which clearly ought to be a 10MA post”. And now it is.

UPDATE October 13, 2014: A much more detailed explanation of the end of total solar eclipses in the distant future can be found on this page, under the “Final Totality” heading.

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Hell yes–wheels down on Mars again!

August 6, 2012

We all stayed up last night to watch Curiosity land on Mars. It was amazing, to be watching the live feed from Mission Control at JPL, hearing the live telemetry being relayed, and then just moments after touchdown get to see the first photo sent back by the rover (it’s grainy and blurry because the transparent lens cap is still on the camera to protect it from the dust kicked up by the landing).

As John Holdren, President Obama’s assistant for science and technology, said, “there’s a one ton automobile-sized piece of American ingenuity and it’s sitting on the surface of Mars right now.”

I was particularly engaged because I had gotten to see parts of the actual spacecraft, including the aeroshell and rocket skycrane, during a tour of JPL two and a half years ago. Strange and amazing to know that the same machinery I saw in the big white room at JPL is now on Mars.

During the landing, data were relayed  back by the Mars Odyssey spacecraft, which has been in orbit around Mars for 10 years, 9 months, and 13 days. This decade-old craft was never designed to function as a data relay, but, you know, engineers are smart. Curiosity joins the rover Opportunity, which is still going strong 3116 days into its 92.5-day mission.

Turns out, we weren’t the only ones watching the landing. The Mars Reconnaissance Orbiter got a photo of Curiosity on the way down, using its HiRISE camera.

This is the second time MRO has caught a Mars lander on the way down; it got a photo of Phoenix descending under its parachute back in 2008.

Happily, today’s xkcd explains why I’m blogging about space on a Monday morning:

Or, as my buddy Jarrod put it on Facebook, “We just landed a one-ton NUCLEAR ROBOT on another planet with a SUPERSONIC PARACHUTE and a FRICKIN’ ROCKET SKYCRANE.”

Good times.

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Curiosity arrives at Mars this weekend!

August 2, 2012

Our newest and largest Mars rover, Curiosity, will arrive at Mars Sunday night or Monday morning, depending on your time zone (image from Wikipedia). I say “will arrive at Mars” because we won’t know if it landed safely or just hit Mars until 7 minutes after the fact. As you can see from this nifty calculator, the distance between Earth and Mars is currently 152 million miles and growing. The landing is scheduled to occur at 10:31 PM, PDT, on August 5, or 1:31 AM EDT, or 5:31 AM UT/GMT.

This video about the landing explains something of the difficulty and complexity of landing a BIG rover on Mars, and some (but not all) of the justification for going with the never-before-attempted skycrane landing method.

Fingers firmly crossed!

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The conjunction last Sunday morning

July 18, 2012

In the latest Mount Baldy observing report I described an awesome predawn conjunction of the moon, Venus, Jupiter, and the bright star Aldebaran. What made it so great was not just the close appearance of four bright objects in the eastern sky, but the almost perfect symmetry of their arrangement: not only did they form an almost perfect arrowhead shape, but the arrowhead pointed straight up toward the Pleiades. All in all, just about the most beautiful celestial sight I’ve seen with my naked eyes.

Just as the kite was flying up over the hill to the east of our observing site, a nice couple drove up and set up a camera. They were Robert and Elizabeth Preston, and they kindly send this photo with permission to post. Trust me, you’re going to want to click through to the big version.

Here’s a closeup of the four conjunction objects from a photo by Terry Nakazono. The moon, Jupiter (top), and Venus (bottom) are all unmodified. I had to crop out the area around Aldebaran (right) and boost the contrast to bring out the star.

I can’t imagine a better end to an observing run.

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Observing report: All-nighter on Mount Baldy

July 15, 2012

Whew! Last night rocked. Terry Nakazono was out from LA, and we had been planning for about two weeks to spend the night observing up on Mount Baldy. We had made a shorter, half-night run up the mountain back in June, Terry to chase faint galaxies with his SkyScanner and me to log a few Herschel 400 objects with the XT10. Last night was basically the same plan, but on steroids–the moon was rising later, and neither of us had anywhere to be today. My wife and son were both out of town, she on work and he on a sleepover, so I was released on my own recognizance.

We got up there about 8:45 and met fellow PVAA member Craig Matthews setting up his 8″ Dob. Former PVAA president Ron Hoekwater joined us a little later on.

Terry was rolling with his SkyScanner again, and aiming for galaxies in Ursa Major and Bootes. I decided to leave the XT10 at home and take the Apex 127 Mak instead. I’ve had that scope for about a year, but before last night I had not really tried it out under dark skies. It did go to the Salton Sea in February, but we were mostly clouded out that night. Five inches is a lot of aperture under dark skies, and I was anxious to see what the Mak could do. Mount Baldy is not stupid-dark like Afton Canyon or western Arizona, but it’s not bad at all. The Milky Way was prominent and showed a fair amount of detail, especially after midnight when a strong marine layer at lower altitudes effectively halved the light pollution to the south (Inland Empire) and southwest (Los Angeles). On light pollution maps Baldy shows as being in the Orange zone, Bortle Class 5, but between the altitude and the marine layer it is sometimes effectively Green (Bortle 4). Last night was such a night.

I also took along the Celestron Travel Scope 70, which I had otherwise only used for quick peeks from my driveway. I’ve been meaning to blog about that scope. Right now you can get the scope, finder, two eyepieces, a tripod, and a backpack carrying case from Amazon for about $70 shipped. The finder is a travesty–an all-plastic “5×20” unit that is in fact stopped down to 10mm right behind the objective. I stripped the so-called optics out of mine and use it as a naked-eye sight tube, in which role it performs admirably, and a heck of a lot better than it ever did as a magnifying finder. The tripod is a joke, the sort of thing that gives other flimsy tripods a bad name. It struggles to hold a point-and-shoot digital camera steady, let alone a telescope, so I donated it to a museum. But the eyepieces are serviceable, the carry bag is fine, and the telescope itself is okay–more on this in the next post–so for $70 it is a screaming deal. As with the Apex 127, I was anxious to see what it could do under dark skies.

It was not yet fully dark when we arrived so I spent some time jawing with Craig. It was cloudless and clear where we were, but we could tell it was raining in the Mojave Desert, because the northeastern sky flickered with distant lightning. And we knew it was far off because we never heard even a hint of thunder. The lightning was not reflecting off clouds but off of the sky itself. It was as if the sky was on the fritz, like a bad florescent bulb. It was a profoundly weird and unearthly effect.

I started my observing run by putting the Apex 127 on Saturn. In addition to observing with “new” scopes, I was also rolling with genuinely new eyepieces. Explore Scientific has been having a CUH-RAY-ZEE sale on their well-reviewed 68, 82, and 100-degree eyepieces, so I sold some unused gear and bought a few: the 24mm ES68, which delivers the widest possible true field in a 1.25″ eyepiece, and the 14mm and 8.8mm ES82s. The Apex 127 is my longest focal length scope at 1540mm, so those eyepieces yielded 64x (24mm), 110x (14mm), and 175x (8.8mm). I also have a 6mm Orion Expanse that gives 257x–that is my default high-mag eyepiece in any scope. The ES eyepieces had just arrived in the mail last week so last night was my first time to try  them out.

Anyway, the seeing was limiting, with the view shaky at 175x and downright ugly at 257x, but Saturn was crisp and jewel-like at 110x and I could see four moons even at 64x. I haven’t checked the charts to see for sure which ones they were, but Titan certainly, and Dione, Rhea, and Tethys probably. I have seen up to five moons of Saturn at once before, but that requires steadier skies than we had last night.

After Saturn I hit a few favorite Messiers, including the globs M13, M5, and M4, all of which were impressively resolved for a 5″ scope. My favorite view of the evening through the Apex 127 was of the galaxies M81/M82 in the same field at 64x, with tantalizing hints of detail visible in both.

Then I got to work, finding and logging Herschel 400 objects. I was chasing mostly open clusters in Cygnus and Cassiopeia. I logged NGCs 6866, 7062, 7086, 7128, 7008 (a planetary nebula) and 7790. I also tried for open clusters NGC 7044 in Cygnus and 136 in Cassiopeia, but could not locate anything I felt comfortable calling a definitive open cluster at the charted locations amid the rich Milky Way starfields. This was also an issue with several of the Cygnus clusters I did log—at high magnification they tended to disappear into the surrounding star chains and asterisms.

Getting skunked is no fun, and by that time I’d been working on H400s for about two hours. For a change of pace, I switched over to the Travel Scope 70 and started plinking at Messiers. With a 32mm Plossl eyepiece I got 12.5x magnification and a stunning 4-degree true field–more like a finder on steroids than a telescope. I started with the Double Cluster as soon as I saw it was over the horizon, then hit M31, but didn’t immediately see its satellite galaxies. Then it was on to the “steam” rising from the teapot of Sagittarius: M8, M20, M22, M24, M25, M23, M18, M17, M16—these last three all nicely framed in the same field—M26, and M11 up in Scutum. Then back to the “bottom” of Scorpio and Sagittarius to catch M6 (M7 had already set behind a hill to the south—bummer), M69, M70, and M54, then all across the sky for M51, M101, M102, M13, M92, M15, back to Andromeda for a nice view of M31, M32, and M110 all prominent in the same field, M52, M103, M33, M76, and M34. I’d seen all these things before, but for most of them this was the lowest magnification I had seen them at, given that my binocular observations of them had mostly been with 15x70s. One of my favorite views of the night was M103 in Cassiopeia with NGCs 654, 663, and 659 in an arc below in the same field.

A little after 3:00 AM it was time for another goal: tracking down the outer giants. I had looked up the finder charts for Uranus and Neptune on Sky & Telescope’s website and logged their positions in my atlas. I found Neptune first, in Aquarius, using the Apex 127. Neptune was a very blue spark, and required 257x to appear non-stellar. Uranus, farther east in Pisces, was obviously non-stellar even at 64x. I also ran up to 257x on it, but the most pleasing view was at 175x. I had seen both planets before, but never as well, nor spent as much time on them as I did last night. Very strange to see giant Neptune as a tiny point of light in the mind-boggling darkness and immensity of space.

After observing planets I went back to the TS70 to continue the Messier survey. Logged M57, M56, M27, M45—absolutely stunning in the center of the field at low power—M72, M73, M2, M30, M75, M71—and old adversary from my early days with the XT6, but dead easy at low mag under dark skies—and M77. I tried for the faint face-on spiral galaxy M74 and suspected something there but couldn’t be sure. For a few these objects, including M72 and M77, I had to go up in magnification to pull them out of the skyglow or make sure they were not stars, using the 25mm (16x) and 17mm (23.5x) Plossls. I tried the 24mm ES68 but it was too heavy for the long cantilever from the mid-tube dovetail to the extended focuser tube of the TS70.

The last big show of the night was an upside-down kite shape rising in the east, with Jupiter at the top, Venus at the bottom, the thin crescent moon on the left, and Aldebaran on the right. I looked at the planets with the Apex 127 at 64x—the near-horizon seeing was bad but Venus’s crescent shape was well-defined, and Jupiter showed a couple of cloud bands and of course the four Galilean moons. Update: Pictures of this conjunction are posted here.

And that was it. The sky was rapidly getting brighter in the east, so we didn’t need artificial light to pack up. We pulled out at 5:25, went to Norm’s diner for breakfast, and I dropped Terry off at his hotel and went home for some badly-needed rack.

My final tally for the night was 8 new H400s, including NGCs 654 and 659; 44 Messiers, 42 of which I saw in the TS70; and 5 planets, including all four gas giants and Venus. Favorite observations were the flashing sky from over-the-horizon lightning, M81 and M82 in the same field in the Apex 127, M31 and both satellite galaxies in TS70, my best-yet views of Neptune and Uranus, and the dawn conjunction of planets, moon, and stars. Between dusk and dawn I observed five of the seven planets visible in a 5-inch scope, missing only Mars and Mercury (both were achievable, it turns out, I just didn’t try for them). It was a heck of a good night.

How did all the equipment perform? Stay tuned for the next post!