Astronomy Across the US

From October, 1997 through February, 1998, I made a cross-country trip with my parents. They are both in their sixties, and wanted someone else to share the driving load in their small motorhome. I was more than happy to fill the spot, so off we went. Sometimes we went too fast, sometimes too slow, and we stayed in too many RV parks and too few National Parks for my taste, but it was a lot of fun anyway. In eight months, we traveled through 23 states. I used any clear, dark nights to observe the stars through my 8x56 binoculars, which doubled as birdwatching glasses during the day. Here is my account of astronomical adventures from the trip.


The skies were cloudy when I was at Flamingo in the Florida Everglades (the southernmost point of my trip), but I spent plenty of time below 35 degrees North, and thus had an additional 10-15 degrees of southern sky to gaze at. Two of the brightest stars in the sky lie between -50 degrees and -60 degrees Declination: Canopus in Carina and Achernar in Eridanus. Canopus, second only to Sirius in brightness at magnitude -0.7, shines through the heavy atmosphere on the horizon, though it may be reddened or flash colors like Sirius so often does when seen from northern latitudes. Achernar, 5 degrees farther south than Canopus and a magnitude dimmer, requires a very favorable southern horizon and probably a latitude below 30 degrees North. I saw Canopus from many places; my best views of Achernar came from Goose Island and Seminole Canyon State Parks in Texas.


Another bonus of southern travel was the chance to see Mercury in November and early December when it was a tough catch for most of the US. From Mercury eastward stretched a line of planets in the evening sky. On numerous occasions, I was able to see eight planets with just my eyes and binoculars. Mercury was low during twilight, Mars and Venus were higher up, I needed binoculars for Neptune, Uranus was often visible to the naked eye, Jupiter was just up from Uranus, and Saturn was high in the Southeast. One more planet, the Earth, was literally close enough to touch. The Moon often appeared near one or more planets, and occulted Saturn on the morning of December 9.

I wish I had had a telescope along to view the Saturn occultation, anything that would show the rings being devoured by the dark side of the Moon. As it was, I had to make do with my 8x56 binoculars, which show Saturn as a small ellipse with no differentiation between disk and rings. I was lucky to see the occultation at all. The weather in Safford, Arizona, was mostly horrible. Even half an hour before the event, slashing wind and rain prevailed. Miraculously, just 15 minutes later, the clouds parted to reveal the two bodies about to meet. The occultation would even be visible to the naked eye. Through binoculars, the Moon covered Saturn's ellipse: just a slight dimming at first, then perceptible motion, and then the remaining portion of the planet seemed to leap forward into oblivion. Shortly thereafter, the clouds returned.

A second occultation was visible from Safford three nights later, this one of Aldebaran. The Moon was very nearly full. I kept trying to trace the circle of the Moon, thinking that Aldebaran would disappear some appreciable distance from the bright part. Instead, the star just kept going and going, and when it disappeared I wasn't sure whether it had been occulted yet or simply appeared to merge with the Moon at the resolution limit of my binoculars.

During December I started viewing Venus during daylight, admiring the sight of a tiny, pure white, perfect crescent through my binoculars. For a month I watched the crescent grow larger and thinner as Venus neared Earth. At times I thought I detected elongation using just my unaided eye. As Venus appeared to close in on the Sun in January, I kept following it by blocking the Sun behind the motorhome and then searching for the planet with my binoculars. Venus passed inferior conjunction early on January 16, 1998. This implies that Venus went between the Earth and the Sun, but from our vantage point Venus was a few degrees north of the Sun. I observed Venus on the 15th and 17th, and would have observed it on the 16th as well had that day not been cloudy. I found the daylight and very bright twilight the best times to view Venus through binoculars (i.e., low magnification instruments of any kind) if the phase is to be discerned. The planet is higher in the sky at this time, so seeing is often better. The real advantage, however, is the lessening of glare from Venus itself, which tends to make the crescent shape less evident in nighttime views.

On the evening of January 20, Jupiter and Mars passed near each other from an earthly point of view. Unfortunately, the clouds ruled most of the day and night. Still, I caught a few glimpses of the pairing through the muck. Through binoculars, the most striking aspect was the difference in color and size of the two planets. Jupiter was a clearly defined disk of creamy yellow, while tiny Mars varied from rusty to pink as it twinkled in the heavy atmosphere near the horizon. The bodies were about 0.25 degrees apart that night, and widening quickly.


Comet 103P/Hartley 2 graced the early evening sky from late November through January. Again, a southern latitude helped bring this object into view. In my binoculars, the comet was a small, round nebulous patch of 8th magnitude, easily seen when the Moon didn't interfere. Meanwhile, another periodic comet was returning to view. Comet 55P/Tempel-Tuttle, the parent comet of November's Leonid meteor shower, has a period of 33 years. During mid-January, it passed roughly 30 million miles from Earth. Like most periodic comets, it was quite faint despite this closeness. Tempel-Tuttle was predicted to be magnitude 9.5, possibly at the limit of my binoculars. Luckily, on January 18 (UT) it seemed to be about one magnitude brighter. I followed it for a few days, temporarily lost it in Cassiopeia's bright Milky Way, then picked it up again as it passed close to the planetary nebula M76 on January 24 (UT). The comet appeared as a large, diffuse fuzzball with a slight central condensation. Comet Hartley 2, though fading at magnitude 9, was still visible across the sky to the west, so these evenings offered two binocular comets in addition to the usual bright constellations and Milky Way objects.

Several meteor showers occurred during my travels. For the Orionids, I was clouded out in Virginia. A gibbous Moon would have interfered anyway. A Full Moon plagued the 1997 Leonids, but the possibility of high rates and bright meteors led me to hope for good weather. Alas, the Texas Gulf Coast was cold and cloudy on the night of maximum. With another Full Moon and a bit of haze in Safford, AZ, I didn't even try for the December Geminids. Perhaps the wind chill was a factor as well. That left the Quadrantids, a shower I had never viewed before. The Quadrantids peak in a few hours on January 3 or 4, depending on leap years. If the morning nearest the peak is clouded out, that's it. You've missed it until next year, which will probably be cloudy as well. In Oregon, clouds are the norm in early January. Perhaps a change of venue, to warm and sunny Organ Pipe Cactus National Monument in Southern Arizona, would make a difference. The Quadrantids were predicted to peak around 19 hours UT on January 3, or Noon MST. That meant that I would have to catch the activity on the rise on the morning of the 3rd. Peak rates are usually 120/hour, but observing before the peak I predicted only 20-30/hour for my viewing window. Alas, the weather came into play, with forecasts for cloudy skies throughout the continental US. At Organ Pipe, the skies remained clear until 2 a.m., just as the radiant was becoming well-placed. Clouds ruled, but cleared enough to observe at 4 a.m. This first observing period lasted 15 minutes, during which I observed 9 Quadrantids and 6 other meteors. In the 1 hour, 50 minutes I was outside, I mixed 1 hour of observing with 50 minutes of breaks due to clouds. During that hour, I counted 31 Quadrantids and 19 sporadic meteors. Skies were fairly transparent when free of clouds, with an average limiting magnitude of 6.7. The Quadrantids were very pretty meteors, moving at a medium speed like the Geminids. Most of the brighter ones showed a touch of blue, though a few were orange. The average magnitude was a rather dim +2.8. Only the two brightest Quadrantids left trains, a brilliant blue -2 and an orange -1. My estimate of the Zenithal Hourly Rate for 11h-13h UT, 1998 January 3, was 41 +/- 6, based on my data. Despite the variable conditions, my observation was successful, and hopefully is a good sign for 1998, when most of the major showers are free from moonlight.


It seemed that relatively few new deep-sky objects were revealed by this change in latitude. Mostly, going south improved the view of objects that are visible with difficulty in Oregon. Throughout the fall, I enjoyed views of the large galaxies NGC 55 and NGC 300, both of which I was barely able to pull out of the muck at the 1997 Oregon Star Party. These objects sit at around -40 degrees Declination. Nearby objects such as the galaxy NGC 1097 and the planetary nebula NGC 1360 were visible, but so small in binoculars as to be of only passing interest. The same was true of the globular cluster NGC 1851 in Columba. The Milky Way region below Sirius presented open clusters aplenty, most beautifully NGC 2451 and NGC 2477. I nicknamed NGC 2451 "Carina's Ruby Necklace" (I know it's in Puppis; Carina must have lost it there). NGC 2477 reminded me of M46; large but cottony and unresolved due to the faintness of its stars. Nearby these is the beautiful Pi Puppis triangle, another color treat in binoculars.

Of course, the objects I was waiting for were Omega Centauri and NGC 5128. Organ Pipe Cactus National Monument was a very nice place to view these objects on late December mornings. This pair is essentially inaccessible in Oregon skies, but at Organ Pipe Omega Centauri rose 10 degrees above the horizon and was easily visible to the naked eye. In binoculars it put the brightest northern globulars, M13 and M5, to shame with its size and brilliance. NGC 5128 was easily visible as a round glow, but try as I might I could not discern the famous dark lane through its center. I hope to observe both of these objects again with a good-sized telescope.

Another major advantage of the southward trek was that I got to observe winter objects in relative comfort. For the first time since I got my binoculars I took prolonged looks at certain objects and regions. I found the Rosette and Flame nebulae easily visible on acceptably dark nights, and I dug into the scads of open clusters out there by starting work on the Astronomical League's Binocular Deep Sky Club list. I thought this list, comprised almost entirely of open clusters, might be dull, but found it a surprisingly pleasant undertaking. Many open clusters have a character visible in binoculars but lost with the higher magnifications and restricted fields of telescopes.


Of the many places we camped, a few stood out as exceptionally transparent and had a minimum of light pollution. The two best observing sites were Seminole Canyon State Historical Park in West Texas and Organ Pipe Cactus National Monument in Arizona. From Organ Pipe, I was able to see the California Nebula through my binoculars without the aid of a nebula filter. Big Bend National Park in Texas is also impressive. A few other potentially good sites escaped evaluation due to El Nino-related weather problems. I hope news of my trip inspires others to go out into the desert and observe.