StarWatch: Moravian Univerity Astronomy

JULY 2023

JULY STAR MAP | MOON PHASE CALENDAR | STARWATCH INDEX | NIGHT SKY NOTEBOOK

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Current Geomagnetic Field:

lunar phases

1402 July 2, 2023: Venus, Mars, and More in the West: This StarWatch is coming to you just a little earlier to take advantage of a beautiful pairing of Venus, Mars, and the bright star Regulus that will be unfolding in the western sky during the next two weeks. Low in the west, Venus is at its brightest magnitude. Mars has dimmed considerably, nearly 30 times since its brilliant, close encounter with the full moon on December 7 of last year. * Observers will have to wait about 45 minutes to an hour after sunset to see the trio in a relatively dark sky. In addition, an unobstructed western horizon will be needed, and as always, binoculars will aid in searching for and spotting Mars, especially in a much brighter or hazy sky. However, do not expect to witness anything except a highly reddened sunset in the west, northwest if the Canadian wildfires send smoke our way again. * Regulus, the alpha star of Leo the Lion, will also be in this grouping and slightly brighter than Mars. Starting on Saturday, July 1, it will appear to the left of Mars, so don't get the two confused. Venus and Mars will be seen in the same field of view in binoculars. Shifting the binoculars up and to the left by about one field of view will allow Regulus and Mars to be captured in the same field. * During the next two weeks, both Venus and Regulus will appear to get noticeably closer to the horizon because the sun will be catching up to the pair, but Venus is also headed for an inferior conjunction, a coming together with the sun, when the Goddess of Love will pass between the Earth and Sol on August 13. Mars will also not be able to escape the sun's glare, but its conjunction with the sun will not happen until much later in the autumn on November 9. * During the next two weeks, watch as Regulus appears to snuggle up to Mars. Mars and Regulus will be within two degrees of each other from July 7 through the 12th and within one degree on the evenings of the 9th and 10th. The closest approach of the pair for the East Coast will occur on the 10th when their separation will be only 2/3rds of a degree (40.4 minutes of arc). Regulus will appear directly under Mars, low in the western sky about 45 minutes after sundown. * Unfortunately, the moon does not enter the picture until July 19 when Mars, Venus, Mercury, and a four percent lit, waxing crescent moon are still above the horizon during early twilight about 30 minutes after sundown. This will be a difficult observation if Mars is included in the grouping, but very attainable if Mars is ignored. As always, binoculars will be helpful, especially if there is some haze near the horizon. Ad Astra!

1403

July 9, 2023: An Epiphany of Sorts

Besides learning to love an Australian breakfast with its beans, sausage, Canadian bacon, potatoes, eggs, sautéed mushrooms, fruits, and the best cups of coffee I have ever consumed (a long black with cream), I had an epiphany of sorts with the way I do photography. I switched from my usual Canon 80D DSLR (digital single-lens reflex) camera system with its fine assortment of zoom lenses to my Google Pixel 7 Pro mobile device which had an excellent reputation for imaging with its three dedicated, built-in camera lenses, as well as taking excellent photos in low light. My niece, Erin Kloss, had shown me her Pixel 6 images several years ago, and I was truly impressed. * You might be laughing at this revelation since the digital revolution in photography has been with us for several decades and billions of phones snap pictures daily, but then you might also understand how finicky I am about imaging and creating a memory when traveling. If I have any artistic talents, they are expressed through my photography. This is likewise not to criticize the pro photographers, like Steve Miller who works for Dan's Camera City in Allentown and uses a DSLR system. His nature photography is superb. The Pixel camera is similarly not for the person who specializes in astrophotography. Here I still recommend a DSLR system or a digital camera specifically designed for astronomical applications. * What "blew me away" regarding the Pixel 7 Pro was its dynamic range, its ability to capture detail in the high contrast, bright portions of an image, as well as information in the shadowy parts of the photograph, something which my Canon 80D has difficulty in obtaining without a good workout in Adobe Photoshop. * The eye opener occurred when I decided to image a sunset while cruising on the Pacific Explorer on the evening before the April 20 total solar eclipse. I brought with me on deck my DSLR system, along with a tripod and my mobile phone stowed in my pocket, figuring that the DSLR would run circles around my mobile device. What I discovered was just the opposite. The Pixel 7 Pro produced superb colors and a higher dynamic range than my DSLR. I enthusiastically submitted to imaging with my mobile phone throughout the rest of my Australian trip, except for the astrophotography that was completed near Franklin River, Western Australia. You be the judge. A PowerPoint presentation of my trip can be found here. Ad Astra!

1404 July 16, 2023: Parkes Radio Observatory: The Dish: This week on July 20, we celebrate the 54th anniversary of humanity's greatest achievement in exploration, when we as a species first landed and walked on the lunar surface. * Neil A. Armstrong gets the credit for the first moonwalk, but I think the whole world was holding its breath and became a part of him as Armstrong piloted and brought the Eagle down to the softest landing of the six missions that humanity has made to the lunar surface. During the height of its activity, 400,000 individuals and 20,000 companies worked on the Apollo program. It was a triumph that could only have been achieved through the cooperative efforts, resources, and leadership of a nation committed to its success. * During my recent visit to Australia, I had the opportunity of visiting the Parkes Radio Observatory, perhaps best known for transmitting to the world most of the video images of the first moonwalk, but not the initial step off of the Lunar Module (LM). * I got my first view of the Parkes Telescope, which collects radio signals from space, on the road which passes it, some three or four miles distant; the 64 meter (210 foot) dish looked more than awkward perched on its circular support structure. It reminded me more of a traditional, but oversized Dutch windmill. See several pictures here. * Commissioned in 1961 as the Southern Hemisphere's then largest radio telescope, there are several reasons why Parkes has remained on the forefront of scientific research today. It is a fully steerable structure capable of looking at any part of the sky that can be seen from its location, nearly 33 degrees south of the equator. Because of its location, Parkes has access to the galactic bulge of the Milky Way which passes directly overhead. That part of the galaxy has a wealth of possible targets to observe. Finally, Parkes has seen numerous upgrades during the time that it has been in operation and is 10,000 times more sensitive than when it was first put into service. An excellent short video tour of the Parkes Observatory can be found here. * When Armstrong successfully piloted the Eagle to the lunar surface, he and Buzz Aldrin were supposed to have a four-hour rest period before donning their spacesuits and walking on the lunar surface. However, Armstrong and Aldrin opted for an immediate moonwalk after their two-hour LM systems check. The landing occurred seven hours before moonrise at the Parkes Observatory, and astronomers there thought that they would miss the entire event. In the end everything worked out because the time required for the astronauts to get into their spacesuits in the cramped quarters of the LM and depressurize the cabin brought the moon at Parkes just to the horizon as the telecast began. At first NASA alternated between the Honeysuckle Creek Tracking Station outside of Canberra, New South Wales, Australia and NASA's Goldstone Station in California. Using a less sensitive 'off-axis' detector, Parkes was able to receive the TV pictures just as the LM TV camera was switched on. Less than nine minutes later, the Moon had risen into the field of view of the Parkes telescope's main detector. Because Parkes was a larger telescope, it captured a stronger signal and so produced better pictures. Houston switched to Parkes and remained with those pictures for the rest of the 2-1/2-hour broadcast (Parkes website). Just before the moon rose, the Parkes Radio Telescope was buffeted by a series of 110 km per hour (68 mph) gusts of wind, strong enough to vibrate the interior supporting structure of the instrument and well beyond its normal operating safety limits. A major feature film, entitled The Dish (See trailer here.) released in 2000 and starring Sam Neill, highlights an embellished account of Parkes' part in the Apollo program. Ad Astra!

1405 July 23, 2023: Delta Aquarid Meteors Fly This Week!: Late July and August signals a pronounced increase of meteor activity which coincides nicely with our desire to spend more time out-of-doors. I have lots of fond memories of camping during these warmer months. My friends and I would specifically choose a dark location to view shooting stars, often in New Hampshire where we would stay at the Jefferson (NH) Campgrounds. The evening hours before midnight were literally a hoot. A bright shooting star would flash across the sky, and pockets of cheers and screams from observant campers would echo against the black dome of the Milky Way-filled sky. Gradually as the hours ticked away, the campground hoopla would slowly fade, so that by 1 a.m., it was normally just my friends and I who were still watching. We would usually recline in silent competition updating each other when a bright meteor was seen. * The nights were always very dewy, just like in our area, so plastic coverings over our sleeping bags and air mattresses, as well as a ground tarp, were a necessity; and if we were imaging the sky for shooting stars, some type of battery operated, dew-busting heater around the lens was mandated. Lately, I have used a battery-operated fan to produce airflow around the lens to alleviate the dew. Chemical hand warmers attached to the camera lens with rubber bands could also serve as a lightweight, inexpensive solution for dew removal. A tripod and a cable release or intervalometer (interval timer which allows many timed exposures to be taken in succession) may also be necessary. * By the end of July, there are at least five minor streams that are active, in addition to the Perseids, which are just beginning to heat up. The best of the lot is the Delta Aquarid Meteor Shower which reaches its maximum activity on the morning of July 30, producing about 15 to 20 meteors per hour from a rural locale and more like 5-10 meteors each hour from suburbia. Unfortunately, the moon is full on August 1, leaving only a narrow window of moonless observation from 3 a.m. until dawn. * The radiant, the location in the sky from where these meteors will appear to diverge, is positioned about five degrees underneath the planet Saturn. View the map which can be seen below. Your fist held at arm's length with the thumb on top is about 10 degrees in angular extent. Early Perseids can be viewed too! * The Perseid Meteor Shower has a reputation for producing memorable fireballs, generally radiating from high in the sky, catching observers off guard if they are viewing the heavens in the south from where the Delta Aquarids originate. More about spotting Perseid meteors next week as the moon wanes and its brightness decreases. For now, good Delta Aquarid hunting. Ad Astra!

1406 July 30, 2023: Perseids to Sizzle this August: The article was originally written for Moravian Magazine to be published in its August 2023 edition.
When I was a kid, money was tight but looking up at the sky was free. Watching for meteors, sketching the constellations, and observing the heavens through my grandfather’s binoculars became favorite pastimes during those early years. This eventually led to a career in astronomy education, first in the Allentown School District Planetarium for 38 years, and presently at Moravian University, where I will start my 14th year of instruction this coming fall semester. Without a doubt it was the Perseid Meteor Shower that inspired my serious career interests in astronomy and my first scientific observations of the night sky. * As comets orbit the sun, they leave behind a trail of dust and gases. If the Earth passes through one of these powder trails, the dross can enter the Earth’s atmosphere where it rapidly disintegrates, causing a column of air to glow around it which creates the meteor or shooting star phenomenon. The Perseids originate from Comet 109P/Swift-Tuttle which was last seen in 1992. The point in the sky from which the Perseids appear to originate (called the radiant) is located in the constellation of Perseus, hence the name of this meteor shower. * Saturday morning through Monday morning, August 12–14, will present a wonderful opportunity to view the 2023 Perseid Meteor Shower. Maximum activity is slated to occur during the post-midnight hours of the 13th. * Meteor showers are not meteor storms, so don’t expect to see shooting stars every second or two. Often Perseids occur in bunches. You might catch two or three in a minute’s worth of observation and then not see any for several minutes. In Montana in 2016, I saw six Perseids in a 15-second interval followed by a period of 10 minutes of inactivity. So don’t become disappointed if you hit a lull; you will see many Perseids if you are persistent. * The most critical factor when looking for shooting stars is the darkness of your observation location. Watching from the Sky Deck at Moravian University in Bethlehem, you may see five Perseids per hour. From a rural location like Cherry Springs State Park, Pennsylvania’s dark-sky observation site near Coudersport, you may average as many as one meteor per minute. * Regardless of your locality, you’ll see the most Perseids by looking toward the zenith, the top of the sky, which is generally the darkest region of the heavens. All meteors that are part of an organized group move through the sky from a radiant. Before midnight that position will be low in the northeast, so Perseid meteors will appear to be spraying outward from a location near the horizon. As the night progresses, the rate of seeing Perseids will increase as the Earth’s rotation moves the radiant higher into the sky. You’ll then be catching meteors from both above and below the radiant. In addition after midnight, the Earth plows into the meteoroid debris similarly to the front windshield of a moving vehicle getting splattered by more raindrops than the rear window. * Many astronomy enthusiasts call the Perseids the best shooting star event of the year, although it does not produce the highest number of meteor counts. For that, try the Geminids in frigid December. The Perseid Meteor Shower, however, combines relatively high rates of meteor counts with warm summer nights when many families are on vacation, including camping trips away from city lights. * Whether you are one of these folks or simply curious to see a meteor event, spend a few hours viewing the dark sky between midnight and dawn on Sunday morning, August 13, when Perseid rates are predicted to be at their highest. Much success in your Perseid hunting. More about the Perseids next week. Ad Astra!