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David A. Huestis has been actively involved in the field of observational astronomy for more than 40 years in Rhode Island. He is a former President of Skyscrapers, Inc., the second oldest continuously operating amateur astronomical society in the United States. He has held that position three times over this period and is now the society’s Historian. David also holds a position at Brown University’s Ladd Observatory as Astronomy Assistant. For a decade ending in 1995 he taught the “Telescopic Astronomy” course at the Boston Museum of Science, and in that same year, he completed his seventh year teaching the mini-course “How to Choose a Telescope” for the museum. David informs the local print and news media about astronomical events by writing a monthly general astronomy column. In December 2007, Huestis published a 180-page hardcover book titled 75 Years of Skyscrapers, highlighting the history of Skyscrapers. Drawing on his primary research, he wrote "Stardust Memories: Frank Evans Seagrave and Halley's Comet – 1910,” an article that appeared in the May 1986 issue of the Rhode Island History Journal, about the notable Providence astronomer who calculated Halley’s orbit with the greatest accuracy of his time. Besides writing, Huestis has published several of his aurora borealis photos. One appeared in the July 1978 issue of Sky and Telescope magazine. That same image was selected by Kelley Beatty, et al, for inclusion in The New Solar System book, the first (1981) and second (1982) editions. That exposure led him to have two aurora images and commentary appear in a sky phenomenon book titled, Sunsets, Twilights and Evening Skies by Aden and Majorie Meinel of Arizona in 1983. He has also freelanced as a book reviewer for the prestigious Sky and Telescope magazine in 1992 and 1993 on the topic of the northern lights. In addition, David has traveled widely to view total solar eclipses: Tennessee (2017), Hawaii (1991), Tanzania (1980), and Canada (1979). During February 2009, Dave received two recognition awards for his public outreach in astronomy. Brown University presented him with an Excellence Award for Citizenship as part of the Ladd Observatory Team. And, the NASA Night Sky Network, in conjunction with the International Year of Astronomy 2009 (IYA2009), presented Dave with a Certificate of Appreciation award for his contributions to public awareness of astronomy and space science as President Emeritus of Skyscrapers, Inc., The Amateur Astronomical Society of Rhode Island. On the night of September 27-28, 2015, Dave provided telescopes on the Bryant campus to view the total lunar eclipse. And on May 9, 2016, he set up telescopes with solar filters to safely view the transit of Mercury across the disk of the Sun.. Professor Huestis has been an astronomy lab instructor at Bryant since January, 2009.


    When guests visit the local observatories, staff astronomers always look to impress them with great views of the Moon, Jupiter, Saturn and Mars when any of these worlds are observable. The wealth of detail visible through each facility’s telescopes can awaken the sense of awe within children and adults alike. What child hasn’t marveled at the Moon’s vast craters? Who hasn’t watched the parade of Jupiter’s Galilean moons orbiting this gigantic planet and not thought about Galileo’s first view of this phenomenal sight? We sky interpreters love to hear the oohs and aahs as folks get a glimpse of Saturn’s magnificent rings for the first time. And when dust storms on Mars don’t spoil the view of this desert-like world, who can’t help but wonder if life may exist beneath its surface? Any night amateur astronomers can introduce casual stargazers to these magnificent worlds is a wonderful experience.

    However, while the afore-mentioned objects get most of the glory, there are two inferior planets of our solar system that are often neglected. No, they do not have any neuroses. Inferior is an astronomical term meaning these planets orbit between the Sun and the Earth. I’m referring to Mercury and Venus. Consequently, they do not stray far from the Sun in the sky from our Earthly perspective. Examine this brief video which explains what we observe. Whenever Mercury and Venus appear above either the eastern or western horizon these events are called elongations. Mercury can appear no more than a maximum of 28 degrees away from the Sun, while Venus can appear no more than a maximum of 48 degrees away from the Sun. Elevation above one’s horizon varies from one elongation to another.

    Throughout the year we have several opportunities to observe these worlds. Unfortunately, we cannot view the surfaces of either of these planets with a telescope, but telescopically we can observe each planetary disk as it goes through phases similar to that of our Moon. Because the position angle between the Earth, Sun and Mercury/Venus is constantly changing due to our orbital positions relative to one another, we see these two planetary disks change phases. Please review this graphic. A picture is most definitely worth a thousand words.

    Perhaps you’ve noticed a bright heavenly beacon high in the southwest sky after sunset since the beginning of the year. That’s Venus. On February 1 the goddess of love will be about 30 degrees above the horizon. On that same evening much, dimmer Mercury will be less than 10 degrees above the west-southwest horizon. You’ll require an unobstructed view to locate it. Through a telescope Venus’ disk will be 73% illuminated, resembling a waxing gibbous Moon phase.

    Mercury’s disk will be about 83% illuminated and will also resemble a waxing gibbous moon phase. Mercury will continue to rise higher into the sky each evening, being at its highest elevation above the horizon on the 10th. This date would be the optimum time to view the closest planet to the Sun. Its phase will then resemble that of a first quarter Moon. After this date Mercury will quickly sink back towards the western horizon and the Sun. Observing opportunities for Mercury are fairly short and are counted in weeks. Around March 1 Mercury will be seen in the morning sky before sunrise. On March 24 Mercury will be at its highest elevation above the eastern horizon.

    After February 1 Venus will continue to rise higher and higher into the evening sky and away from the Sun and horizon. Venus’s larger orbit results in the planet appearing much farther from the Sun in our sky than Mercury does. Therefore, observing opportunities for Venus are counted in months. On March 24 Venus will be at its greatest elongation from the Sun, and therefore at its highest point (about 40 degrees) above the horizon after sunset. The phase will now look like that of a first quarter Moon. Four days later on the 28th a waxing crescent Moon will be located about six degrees to the left of Venus. This sky scene will be a beautiful image to capture with a camera.         

    It is interesting to note that Venus has been approaching the Earth since superior conjunction (passing behind the Sun from our viewpoint) on August 14, 2019. As Venus draws closer to our planet the size of its planetary disk gets larger. See this website for a graphic that illustrates this progression. By March 24, despite the waning phase, Venus’ brightness will remain fairly constant because its larger apparent size compensates for the decreasing illumination.

    In addition, if you know where to scan, you can even observe Venus in broad daylight, being careful not to stray too close to the Sun for eye safety. Use a building to block the Sun from direct view before beginning your sweep of the sky. However, it’s best to observe Venus in early twilight before the sky darkens. Venus is so bright that too much contrast is a problem when observed in a dark sky. A small refracting telescope or even a scope used for bird watching will show Venus’ changing phase. Check it out every couple of weeks or so.

    After elongation Venus will begin to sink towards the horizon. It will still be coming towards us, all the time the phase will be decreasing to a smaller and smaller crescent. We’ll lose sight of Venus by the end of May.   

    In conclusion, please remember, weather permitting, the local observatories remain open during the winter months to share beautiful views of the heavens. Snow, ice or below freezing temperatures can force closures, so please check the respective websites for any cancellation notices and observing schedules before venturing out for a visit. Seagrave Memorial Observatory in North Scituate is open every clear Saturday night. Ladd Observatory in Providence is open every clear Tuesday night. The Margaret M. Jacoby Observatory at the CCRI Knight Campus in Warwick is open every clear Wednesday night. Frosty Drew Observatory in Charlestown is open every clear Friday night.

    I hope that Venus, the Roman goddess of love, will smile upon you and yours on Valentine’s Day. Just be vigilant against any errant arrows from her son Cupid!

    Clear skies to all.


Astronomical Highlights for 2020

Happy New Year everyone. Yet another year has passed into the history books, and I am once again presenting some of the astronomical highlights upcoming in 2020. While there are a couple of impressive upcoming events, any time the skies are clear and transparent many stargazers are enticed out under the vault of the heavens to explore our beautiful universe.

    The winter months around Southern New England can be quite cold, and I for one need some incentive to spend much time outdoors observing the sky. Fortunately, the sky gods provide the Quadrantid meteor shower which peaks on the night of January 3-4. While this shooting star display can produce up to 100 meteors per hour during peak, a more modest 60 meteors per hour is likely under a moon-less sky. This shower also sports a very narrow peak of activity, only several hours in duration, that can easily be missed. However, if you have the time and can tolerate the usual cold temperatures, the Quadrantids don’t disappoint the well-prepared observer.

   The fast-moving Quadrantids blaze across the sky at 25.5 miles per second. These blue meteors can appear anywhere in the sky, but their radiant point (the area of sky from where the meteors appear to originate) is not far from the end star, Alkaid, of the Big Dipper’s handle. From midnight till dawn, this area of sky will rise higher and higher above the northeast horizon. By 4:00 a.m. the radiant will be almost at zenith (directly overhead). You’ll know you’ve spotted a Quadrantid meteor if its dust train through the sky points back to the radiant point. A First Quarter Moon will set just after midnight, so it will not interfere with observing as many shooting stars as possible between then and dawn’s early light.

    Despite being wintertime, I still recommend that you get comfortable in a lounge chair to conduct your observing session. Snuggle up in a well-insulated sleeping bag and keep your head and hands warm. Just don’t get too comfortable and fall asleep like I did many moons ago!

    Speaking of moons. There are four supermoons in 2020. While the term supermoon is not an astronomical term, it has been widely used in recent years to describe a Full Moon’s closest approach (perigee) to the Earth. However, the caveat is, to be called a supermoon the moon has to be within 90 percent of its closest distance to the Earth. Following this arbitrarily assigned criteria there are supermoons on February 9, March 9, April 7 and May 7. The April 7 Full Moon is the closest one for the year and may appear slightly larger and brighter than usual.

    The most interesting highlight for 2020 will be a close encounter with Mars. Every 26 months the “Red Planet” is in opposition. That means when the Sun sets Mars will rise. October 13 is the date of opposition. The close approach of our two worlds occurs a week earlier on October 6 when our planetary neighbor will be only 38.6 million miles away. That distance is just a little farther away than Mars was at its last close approach on July 31, 2018. Also, in 2020 Mars will rise much higher into our much less hazy October sky. A telescope should reveal much detail on the Martian surface.

    However, just before the July 2018 close approach a global dust storm completely enshrouded Mars making it impossible to view any surface details. And it could happen again, since circumstances will once again favor the formation of dust storms. Should observing conditions on Mars evolve in our favor, the local observatories will certainly focus their attention on this fascinating world. Barring any major dust storms, I will present an observing guide to help identify large-scale features with a telescope.

    An interesting celestial dance of Jupiter and Saturn will commence for most casual stargazers on May 12 when both planets will sit just above the eastern horizon around midnight. A waning gibbous Moon will also join the pair. From this date forward these two worlds will appear to move closer to one another from our perspective. On December 21 they will be so close that they will appear as one object to the naked-eye just after sunset 15 degrees above the horizon. This “Great Conjunction” will be the closest these two worlds have been since 1623.

    To observe this event, you’ll need to find an observing location that commands an unobstructed view towards the southwest. If you have a telescope by all means use it to focus in on this beautiful sight. Use medium to high-power and you’ll observe both worlds in their glory in the same field of view. Hopefully the weather will cooperate, as the next Jupiter/Saturn conjunction on November 5, 2040 won’t be as “Great.” This December 21st event is really something special to note on your calendar.

    In addition, 2020 provides two penumbral lunar eclipses for our location Unfortunately, the Moon does not move into the Earth’s dark shadow. In fact, for the July 5 event only about one-third of the lunar surface will slide into the lighter penumbral shadow. Even at its maximum I doubt whether any shadow will be detectable. For the November 30 penumbral lunar eclipse roughly three-quarters of the lunar surface will pass through the lighter shadow, but will still not be close to the dark umbra. A keen-eyed observer knowing what to look for may detect a slight shading of the top portion of the lunar disk. Good luck.

    In conclusion, please remember, weather permitting, the local observatories remain open during the winter months to share beautiful views of the heavens. Snow, ice or below freezing temperatures can force closures, so please check the respective websites for any cancellation notices and observing schedules before venturing out for a visit. Seagrave Memorial Observatory in North Scituate is open every clear Saturday night. Ladd Observatory in Providence is open every clear Tuesday night. The Margaret M. Jacoby Observatory at the CCRI Knight Campus in Warwick is open every clear Wednesday night. Frosty Drew Observatory in Charlestown is open every clear Friday night.

    Some of the topics highlighted in this column may be covered in depth as an event date approaches.

    Please clip and save the following chart showing the observing prospects for the 2020 meteor showers. These displays of shooting stars only require your eyes, dark skies, and patience to enjoy.

Clip & Save

Meteor Shower Prospects for 2020

Month Shower Date Moon Phase
January Quadrantids 3-4 First Quarter
April Lyrids 22-23 New
May Eta Aquarids 6-7 Full  
July Delta Aquarids 28-29 First Quarter
July Capricornids 29-30 Waxing Gibbous
August Perseids 12-13 Last Quarter
October Orionids 21-22 Waxing Crescent
November Leonids 17-18 Waxing Crescent
December Geminids 13-14 New

        Keep your eyes to the skies for 2020 and always.

        Before you know it, I will be writing my highlights column for 2021!!


    As quickly as it started, 2019 will soon be in the history books. I for one am happy to see it go. A cloudy and rainy spring, hot and humid heat waves during the summer, then the EEE mosquito threat have conspired to prevent casual stargazers and amateur astronomers alike from enjoying the night sky and all the wonders it holds. It would be great if we could end the year on a high note, but the sky gods are not smiling down on us for December.

    Though the Geminids are the best meteor shower of the year, peaking on the night of December 13-14, the Full Moon on the 12th will overwhelm all but the brightest meteors. To complicate matters further on the peak night, that bright moon will be sitting right in the middle of the Gemini constellation. While you won’t require my usual star map to find Gemini, the proximity of the Moon to the region of the sky from where the meteors appear to radiate (near Gemini’s brightest stars, Castor and Pollux), will certainly reduce your meteor count. .

    However, one does not have to look directly at Gemini to catch a few of the brightest shooting stars. In fact, the Geminids are fairly bright and also have a reputation for producing exploding meteors called fireballs, My point: if the weather cooperates on peak night do not give up on the Geminids. You might just glimpse a few bright Geminids as they enter our atmosphere at 21.75 miles per second.

    Later in the month don’t forget that the Winter solstice begins at 11:19 p.m. on the 21st. Notice how low an arc the Sun travels across the sky. After this date and time the Sun’s arc will rise higher and higher each day as it appears to travel northward in our sky, reaching the Vernal Equinox (Spring) on March 19, 2020, at 11:50 p.m. EDT (Eastern Daylight Time). The apparent shift of the Sun’s position in the sky is the result of the Earth’s fixed axial tilt of 23.5 degrees as it revolves around the Sun. See my column Reason for the Seasons to refresh your knowledge on this topic.

    Also, as we approach the holiday season, many folks often ask me about the mystery of the Christmas Star. An unabridged version of my latest treatise on this topic can be found on the Skyscrapers website for your examination.

    Unfortunately, as we move into December, Jupiter will set soon after sunset, and Saturn will follow within 90 minutes. Since the local observatories don’t open until 7:00 p.m., these beautiful worlds will be unobservable. However, there are a wide variety of other objects to view. As long as the observatory grounds are accessible, the telescopes will be available for you to explore “deep sky” objects within the brightest constellations of the night sky. The Orion Nebula and the Andromeda Galaxy will be well placed for exploration. Many open star clusters and beautiful double stars will await your scrutiny. And our solar system’s two outermost planets, Uranus and Neptune, will show as small blue-green orbs in the telescopes available. Knowledgeable sky interpreters will be on hand to introduce you to these and other celestial wonders. Be sure to visit each observatory’s website prior to setting out for a field trip to these facilities, as wintry conditions can force unexpected closures.

    And finally, I am always looking for a great sky scene that you can easily image with just a simple camera. Just after sunset on December 28, look towards the southwest sky. A waxing crescent Moon will be a mere three degrees (6 full moon diameters) from brilliant Venus. This event definitely merits being recorded.   

    Seagrave Memorial Observatory in North Scituate is open to the public every clear Saturday night. However, in December Seagrave will be closed on the 14th. Ladd Observatory in Providence is open every clear Tuesday night. However, Ladd will be closed on Christmas Eve (24th) and New Year’s Eve (31st). The Margaret M. Jacoby Observatory at the CCRI Knight Campus in Warwick is open every clear Wednesday night. However, this observatory will be closed on Christmas Day night (25th) and New Year’s Day night (Jan 1). Frosty Drew Observatory in Charlestown is open every clear Friday night year-round.

   Happy holidays and clear skies to all.


   Venus and Mercury transits occur when these worlds, which orbit between the Earth and the Sun, can be seen to pass directly in front of the solar disk and transit across the face of our star. Why don’t we experience a transit of Venus or Mercury every time they pass between the Earth and the Sun (called inferior conjunction)? It all has to do with the orbits of these planets and our ever-changing viewing angle. Most of the time Venus and Mercury pass above or below the solar disk as seen from the Earth. This concept is simply stated here, but it took the greatest astronomical minds of the past to solve this great mystery. The process took much observation, dedication and deduction to determine the solar system design and the celestial mechanics that govern its motion.

    Venus transits are rare astronomical events. They always occur in pairs, eight years apart. We last experienced transits of Venus in 2004 and 2012. Their immediate predecessors occurred back in 1884 and 1882. And the next pair won’t be until 2117 and 2125!

    However, another planet can transit the Sun—Mercury. Though not as rare as Venus transits, transits of Mercury occur 12-13 times per century. The last one occurred on May 9, 2016 and it was observed in its entirety locally. The Mercury transit prior to that occurred on November 8, 2006, but in Southern New England we were clouded out. Unfortunately, the next one visible here after the upcoming November 11 event won’t be until May 7, 2049.   

    I encourage the reader to examine the brief article at this website to understand why transits were once so important that expeditions were sent around the world to observe them.

    First and foremost I must express several very important words of caution. My mantra is: when observing the Sun, observe caution as well. Do not attempt to observe this event unless you are an experienced solar observer. Mercury is so tiny that you won’t be able to detect it in transit with the naked eye anyway, so don’t be tempted to try. Number 14 welders’ glass will not show Mercury either. DO NOT use exposed film of any kind. This method is not safe under any circumstance. In past columns I have instructed folks on how to build a solar eclipse viewer using a shoe box. This observing method also won’t work in this circumstance because the projected solar disk is so tiny that Mercury’s even smaller silhouette won’t be detectable. Furthermore, unfortunately those solar eclipse glasses practically everyone obtained for the August 21, 2017 solar eclipse will not reveal tiny Mercury’s disk either.

    If you have never observed the Sun before this event, don’t start now! Don’t risk your eyesight due to an oversight or an outright mistake. Even if you have one of those department store refractors that often come with small glass or plastic filters, do not be tempted to use them. They have been known to shatter when exposed to the Sun’s concentrated image. (Many years ago, when I first started out in astronomy, I had one of those glass/plastic filters shatter during a partial solar eclipse. Luckily, I wasn’t looking through the eyepiece at the time. But it was a very close call.)

    If you use an unfiltered telescope to project the Sun’s image on a white screen, remember to be very cautious if other folks, especially children, are nearby. You don’t want anyone accidentally stepping up to an unguarded eyepiece to take a look. And regarding eyepieces, do not use cemented eyepieces. Use only those that are air-spaced. Eyepieces have been ruined when the cement has melted due to the concentrated sunlight collected by a telescope.

    Otherwise, experienced astronomers use special solar filters that prevent more than 99.99% of the light from even entering the telescope. That includes the dangerous infrared wavelength as well.

    Regardless of which telescope method you use, please remember to block off your telescope’s finder scope. I have seen observers singe their hair or clothes by failing to do so!!

   Our location here in Southern New England will allow us to observe the 2019 transit in its entirety. From start to finish the transit will last five and a half hours. That’s a long duration event to allow interested individuals to be able to view even a few minutes of Mercury’s passage across the solar disk.

    Please note that all times with this article are provided in Eastern Standard Time and have been specifically calculated for Providence. (Times do vary slightly by geographic location, so if you are going to be outside of the area, you may want to check online for specifics.)

    Locally the transit begins bright and early at 7:34:43 a.m. with the Sun about ten degrees above the southeast horizon. This is the moment of 1st contact when the tiny silhouette of Mercury will begin to appear along the lower left (east) edge of the Sun approximately at the eight o’clock position. Because the Sun arcs across the sky depending upon geographic location, and because we live on the surface of a sphere, the beginning and ending positions will differ greatly from the accompanying graphic. It’s all a matter of perspective. It will take two minutes for Mercury to emerge fully onto the solar disk.

    Just before it does so, a keen-eyed observer should notice the “black drop” effect. Many members of Skyscrapers observed this “black drop” during Venus’ transit in 2004. High magnification will be necessary to see this effect due to Mercury’s small size. When Mercury is seen fully in front of the solar disk is the time of 2nd contact at 7:36:24 a.m. The image of Mercury will be quite small and much darker and rounder than any sunspot. (With the Sun currently at solar minimum there will be few if any sunspots to use for comparison.)

    Mercury’s motion will continue to carry it across the face of the Sun from east (left) to west (right). The mid-transit point will occur at 10:19:46 a.m. with the Sun 28.6 degrees above the south-southeast horizon. At 1:03:13 p.m. Mercury will reach the right edge of the Sun. This is 3rd contact.  Just prior to this time an observer will once again have another opportunity to observe the “back drop” effect. Then at 1:04:54 p.m. Mercury will exit the solar disk completely. This event is called 4th contact. The Sun will then be about 26.8 degrees above the south-southwest horizon.

    If you are not an experienced solar observer and wish to experience this transit, you may be able to do so at some of the local observatories. At the time of this writing in early October, only Frosty Drew Observatory at Ninigret Park in Charlestown has an observing program scheduled. If and when any of the other facilities offer Mercury transit observing opportunities, I will email the media with the details.

    And heavens forbid the skies are cloudy here on November 11. I’m sure there will be many websites streaming the event live. I agree that watching online sites is not the same as experiencing the transit firsthand, but if the weather doesn’t cooperate, you may have no choice but to pull up a chair in front of your computer screen and watch the progress of the event. This course of action is also an option if you can’t observe it safely yourself or can’t travel to an organized observing program. Should the opportunity pass you by for any reason, you won’t have another chance locally until May 7, 2049.

    Good luck in observing this interesting astronomical phenomenon, and remember to keep your eyes safe.

November Meteor Showers

First up for November is my reminder to be sure to set your clocks back one hour on Sunday, the 3rd. That’s when most of the United States switch back to Eastern Standard Time from Daylight Saving Time. The mnemonic is “spring ahead and fall back/behind”. Thank goodness for most of us it occurs on a weekend!

    While the premiere astronomical event during November will be the transit of Mercury between the Earth and the Sun (which I will preview in a separate column), there are two meteor showers as well.

     From November 4th thru the 6th watch the sky for no more than a half dozen or so Taurid meteors. These often very bright yellow fireballs (meteors that explode and fragment into multiple pieces) are fairly slow and enter our atmosphere at approximately 17 miles per second. Observe after midnight to increase your chances of seeing one. Look in the general direction of the constellation Taurus. To locate Taurus find the V-shaped pattern that defines the bull’s face, or locate the Pleiades — the Seven Sisters star cluster. A waxing gibbous Moon will overshadow all but the brightest of the meteors this year.

        Another more productive meteor shower will occur on the night of November 17-18, with the peak of the annual Leonids between midnight and dawn on the 18th. Unfortunately a bright waning gibbous Moon in neighboring constellation Cancer will also overshadow all but the brightest of the shooting stars. An observer well away from man-made light pollution may see about 10-15 green or blue shooting stars per hour, though the interfering moonlight may reduce that optimistic forecast. Please note a cluster of stars above the Moon. It is the Beehive Cluster. Check it out with binoculars.

    The Leonids blaze across the sky at around 44 miles per second as they hit the Earth’s atmosphere nearly head-on. The resulting display produces many fireballs, with about half of them leaving trains of dust that can persist for minutes. The area of sky where the meteors appear to radiate from is in the Sickle (backwards question mark) asterism in Leo. Clear skies and some luck will favor seeing as many shooting stars as possible.

    Finally, just after sunset on the 24th look towards the southwestern sky to see a conjunction (close proximity of two celestial bodies) of Venus and Jupiter ten degrees above the horizon. They will be about 1.4 degrees apart—three full moon diameters  Venus will be the brighter of the two planets.

    Keep your eyes to the skies.