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This website has been created by and is supported by a group of Boston, MA - area amateur astronomers. It is intended to be a convenient site to access news and information about astronomy and space-related activities of interest to the community and the public.




Next Astronomy Course


Introduction to Astronomy


We sit around our campfires as the ancients did, and ponder. How did the Universe come into existence? How did life begin? Are we alone? But now we see a Universe around us containing black holes, dark matter, and expanding space. What does it all mean? In this course we’ll sit around our own campfire, and try to piece together the stories that modern astronomy is teaching us.  


One meeting will be at a local observatory.


No math or science background required!


Meets at the Cambridge Center for Adult Education, 8 Tuesdays: September 19 -  November 7, 2017, 7:45 PM - 9:15 PM.




August Astronomy-Related Events in the Boston Area  



Saturday, August 11, August 26, and September 9, 2017, 7:30 PM - 10:30 PM

Sea the Stars Cruise

We wish upon them, gaze at them, aim for them, and sometimes even thank our lucky ones! For centuries, stars have fascinated us, guided us, and provided us with nighttime illumination and splendor. Sadly, the abundance of bright lights and tall buildings has made stargazing for city dwellers difficult at best and often pretty much impossible. But fear not, amateur astronomers and celestial connoisseurs, the Museum of Science and Boston Harbor Cruises have teamed up to bring you the Sea the Stars Cruise!

Onboard a high-speed catamaran, you'll travel to where the city lights and congestion are just a bright memory for a stargazing opportunity like no other in the city.

Cruise highlights include:

Three-hour cruise aboard a high-speed catamaran from Long Wharf, Boston

Expert commentary and star identification from Museum of Science Astronomy Educators

Narration on the history and importance of celestial navigation – how sailors used the stars

Related video and content

Plenty of outdoor viewing space

Comfortable indoor seating

Cash Bar and snacks available onboard

Please note: Stargazing is dependent on clear skies. If forecasts show that clouds or precipitation will rule out good viewing, the cruise will be cancelled. Decisions on any cancellation will be made by 2:00 pm on the day of the cruise. Ticket passengers will be notified and refunds will be made. If, during the cruise, visibility limits successful stargazing, passengers will receive a rain check to return for a future Sea the Stars Cruise.

August 12 cruise coincides with the annual peak of the Perseids meteor shower, which is best seen in dark skies far away from the city!

For tickets and more information, visit

Sponsored by Boston Harbor Cruises.



Monday, August 21, 2017, 1:28 PM

Arlington Astronomy Nights

Robbins Farm Park

Arlington, MA

Don't miss a partial Solar Eclipse! I may or may not have the telescope out in the park, but be sure to take a step outside and, using proper eye protection, watch as the Moon moves across the Sun, covering as much as 60% ofe surface. Maximum eclipse will occur at 2:46pm for us and the eclipse will conclude at 3:59pm as the last edge of the Moon moves away from the edge of the Sun.




Plus (ongoing):        



Boston University

Boston, MA.
Open Night at Coit Observatory most Wednesdays 8:30 PM - 9:30 PM. 




Thursdays and Fridays (during July and August), 8:30 PM - 10:00 PM

Guilliland Observatory

Museum of Science

1 Science Park

Boston, MA 02114





The Sky Report for the Month of August 2017


 There is a partial lunar eclipse on August 7. It will be visible in eastern Europe, Africa, Asia, and Australia.


There is a total solar eclipse on August 21. The path of totality crosses the United States from Oregon to South Carolina, and a partial eclipse is visible throughout the conterminous Unites States. (See our “What’s New” section for more.)


A new mobile app developed by the Smithsonian can enrich your experience of the “Great American Eclipse”. It’s available for iTunes and Google Play.



Current Night Sky: At A Glance


            Phases of the Moon:                           



Full Moon

August 7

2:11 PM EDT

Last Quarter Moon

August 14

9:15 PM EDT

New Moon

August 21

2:30 PM EDT

First Quarter Moon

August 29

4:13 AM EDT



The Moon & Planets:



Planet Visibility:


In Evening (after sunset):

    Mercury, in W

    Jupiter, in W

    Saturn, in S

    Neptune, in E 


 At Midnight:

    Saturn, in SW

    Neptune, in SE

    Uranus, in E


 In Morning (before sunrise):

    Neptune, in SW

    Uranus, in S

    Venus, in E 





    •     There are no comets brighter than magnitude 8 visible this month.


  •     The Perseid meteors peak on August 12th. For viewers in North America, they will be best after midnight on the nights of the 11th -12th and 12th -13th. Unfortunately, the Moon, five days past full, will interfere and wash out the fainter meteors. This shower can produce rates of over 100 meteors per hour under ideal conditions; this year you may have to settle for 20 – 30 per hour.





There is a partial lunar eclipse on August 7, as the Moon moves into Earth’s shadow. The yellow circles in the image above show the shadow that Earth casts into space. When points on the Moon are within the inner circle, or umbra, no direct sunlight can reach them (although some sunlight does get refracted by Earth’s atmosphere). Locations within the outer circle, or penumbra, are only partially illuminated by direct sunlight. The image shows the Moon at maximum eclipse; during this “shallow” eclipse, the Moon only penetrates slightly into the umbra. And please note that this lunar eclipse is visible only from the Eastern Hemisphere. A half of a lunar cycle later, the eagerly awaited total solar eclipse is visible from the United States.

(August 7, 2017 – 6:20 PM UT).





The Perseid meteors originate in debris streams left by previous passages of the comet Swift-Tuttle; every year at this time, Earth plows through these debris streams, and the component particles – most of them no larger than a grain of sand – burn up as they encounter Earth’s atmosphere. This will not be a favorable year to view the Perseids, as the light from the Moon will obscure the fainter meteors when the shower is at its best between midnight and dawn. (Please note: it is extremely unlikely that you will see more than one meteor at a time!) (Courtesy: Sky & Telescope).

August 12, 2017, 11:00 PM EDT)

Saturn remains prominent in the evening sky well into fall. The tilt of the rings toward us is almost at its maximum. If you have a modest backyard telescope, you may be able to trace the thin black line of the Cassini Division all the way around the planet. Saturn’s largest moon, Titan, is at the far right of the image. Some smaller moons, Dione and Tethys, are closer in to the right of the planet. Rhea, the second largest moon, is at the far left of the image, with Enceladus closer in.

(August 23, 2017; 8:15 PM EDT).


The “Great American Eclipse” Has Arrived!


The time is finally here. After years of preparation, months of finalizing of arrangements, and weeks of mounting anticipation, the “Great American Eclipse” is almost upon us.


Total solar eclipses are not in themselves rare. There can be anywhere from none to up to two per year. But they have a nasty habit of occurring in remote - or sometimes inhospitable - parts of the world. The last one, for example, made landfall only on some islands in Indonesia.


But the eclipse of August 21, 2017, will be special. It will be the first occasion since 1979 that the path of totality falls within the continental United States – and even then, it covered only parts of five states in the Pacific Northwest. This one will make a complete traverse of the country – from the coast of Oregon to the shores of South Carolina. The last time we had a cross-country eclipse was nearly a century ago – in 1918! No wonder that the 2017 event is being hailed as “The Great American Eclipse”!


In fact, even outside the path of totality, all locations within the conterminous United States will witness at least a partial eclipse of varying duration, with the Moon’s disk covering only a portion of the Sun.


Even within the path of totality, the duration of the eclipse varies, in accordance with distance from the exact centerline of the path of totality.


The duration of eclipse at the centerline varies from 1 minute and 59 seconds at landfall on the coast of Oregon, to a maximum of 2 minutes 40.1 seconds near Hopkinsville, KY., then decreasing again to 2 minutes 34 seconds as it leaves the South Carolina coast.





The path of totality crosses the country from west to east, through parts of 14 states: Oregon, Idaho, Montana (just barely), Wyoming, Nebraska, Kansas, Iowa (also barely), Missouri, Illinois, Kentucky, Tennessee, North Carolina, Georgia, and South Carolina. Major cities within the path are Salem, OR,  Idaho Falls, ID, Jackson and Casper, WY, Lincoln, NE, Kansas City, KS, St. Louis, MO, Knoxville and Nashville, TN, and Charleston, SC. (Courtesy: Sky & Telescope).





   During the few precious moments of totality, the Moon completely covers up the Sun. This reveals features such as the Sun’s delicate corona (seen above) and prominences, as well as the so-called Bailey’s Beads and the “Diamond Ring” effect, as the Moon’s ragged limb covers and uncovers the Sun. (Courtesy F. Espenak,


Needless to say, weather prospects are of the utmost importance. No one can ensure clear skies on eclipse day; nevertheless, eclipse “experts” have done extensive studies of climate, meteorological data, and weather records for locations along the path of totality. They have concluded that the best chances of clear skies are in places such as the high desert terrain in Oregon or Wyoming. Unfortunately, it may be too late to make arrangements to stay – in those areas or others – as many hotels, motels, campgrounds, and RV parks along the path of totality are completely booked – and, in some cases, have been for years!


This would be a good time to call that friend or relative that has a home near the path of totality.


Of course, you could always wait until April 8, 2024. On that date there will be another total solar eclipse, beginning with landfall in Mexico, and traversing the U.S. from Texas into northern Vermont and Maine; it continues on through the Maritime Provinces of Canada.


Is it too soon to look forward to that one? Even as this 2017 eclipse arrives, don’t be surprised to hear people already making plans for 2024!


A WORD OF WARNING: NEVER LOOK AT THE SUN WITHOUT SUITABLE EYE PROTECTION, unless you happen to be within the path of totality - and even then only for those one or two minutes when the Sun is completely covered up by the Moon. Sunglasses, exposed film, or smoked glass do NOT provide adequate protection, as damaging infrared light can easily pass through. Use only #14 welder’s glass or “eclipse glasses” containing silvered Mylar film. Preserve your vision so you’ll be able to enjoy this eclipse, the next one, and life in between.



August Major Astronomical Events       
Aug. 2 Wed. 2:05 AM EDT Cassini Orbit 286 Ring Crossing # 16 (2920 km from Saturn, 4790 km from D ring)
Aug. 2 Wed. 1:55 PM EDT Moon @ apogee (405,025 km / 251,671 mi)
Aug. 3 Thur. 3:00 AM EDT Moon 3° N of Saturn
Aug. 7 Mon. 1:19 PM EDT Cassini Orbit 287 Ring Crossing # 17 (2940 km from Saturn, 4760 km from D ring)
Aug. 7 Mon. 1:22 PM EDT Partial lunar eclipse begins
Aug. 7 Mon. 2:11 PM EDT Full  Moon ("Full Sturgeon Moon")
Aug. 7 Mon. 2:20 PM EDT Partial lunar eclipse maximum
Aug. 7 Mon. 3:18 PM EDT Partial lunar eclipse ends
Aug. 9 Wed. 7:00 PM EDT Moon 0.9° S of Neptune
Aug. 10 Thur. 11:00 AM EDT Sun enters Leo
Aug. 12 Sat. 3:00 PM EDT Perseid meteors peak
Aug. 13 Sun. 1:00 AM EDT Moon 4° S of Uranus
Aug. 14 Mon. 9:15 PM EDT Last Quarter Moon
Aug. 15 Tue. 12:22 AM EDT Cassini Orbit 288 Periapsis Dip # 1 (1710 km from Saturn, 6990 km from D ring) "Final Five" .
Aug. 16 Wed. 3:00 AM EDT Moon 0.4° N of Aldebaran
Aug. 18 Fri. 9:18 AM EDT Moon @ perigee (366,121 km / 227,497 mi)
Aug. 19 Sat. 1:00 AM EDT Moon 2° S of Venus
Aug. 20 Sun. 11:23 AM EDT Cassini Orbit 289 Periapsis Dip # 2 (1660 km from Saturn, 6040 km from D ring) "Final Five"
Aug. 21 Mon. 1:28 PM EDT Partial solar eclipse (in Boston) begins
Aug. 21 Mon. 2:30 PM EDT New Moon
Aug. 21 Mon. 2:46 PM EDT Partial solar eclipse (in Boston) at maximum (70% diameter, 63% surface area)
Aug. 21 Mon. 3:59 PM EDT Partial solar eclipse (in Boston) ends
Aug. 25 Fri. 9:00 AM EDT Moon 3° N of Jupiter
Aug. 26 Sat. 5:00 PM EDT Mercury @ inferior conjunction
Aug. 27 Sun. 10:20 PM EDT Cassini orbit 290 Periapsis Dip # 3 (1630 km from Saturn, 6070 km from D ring) "Final Five"
Aug. 29 Tue. 4:13 AM EDT First Quarter Moon
Aug. 30 Wed. 7:25 AM EDT Moon @ apogee (404,309 km / 251,226 mi)
Aug. 30 Wed. 10:00 AM EDT Moon 4° N of Saturn


An Overview of Major 2017 Astronomical Events

Jan. 3 Tue. 7:14:38 AM EST Latest sunrise of year in Boston
Jan. 3 Tue. 9:00 AM EST Quadrantid meteors
Jan. 4 Wed. 9:00 AM EST Earth @ perihelion (0.98331 AU / 147,101,111 km / 91,404,393 mi)
Jan. 12 Thur. 8:00 AM EST Venus @ greatest eastern elongation (47.1° E); Evening "Star"
Jan. 12 Thur. 6:00 PM EST Venus 0.4° N of Neptune (21' 57" in Boston)
Jan. 17 Tue. 8:00 PM EST Vesta @ opposition (mag. 6.3)
Jan. 19 Thur. 1:00 AM EST Jupiter 2.7° S of Moon
Jan. 19 Thur. 5:00 AM EST Mercury @ greatest western elongation (24.1° W); Morning "Star"
Jan. 31 Tue. 6:00 PM EST Mars, Venus, and waxing crescent Moon fit into circle 6° in diameter
Feb. 11 Sat. 5:34 PM EST - 9:53 PM EST Penumbral Lunar Eclipse
Feb. 17 Fri. 2:00 AM EST Venus @ greatest illuminated extent
Feb. 26 Sun. 7:10 AM EST - 12:38 PM EST Annular Solar Eclipse (SW Africa. S. Atlantic, South America)
Feb. 26 Sun. 8:15 PM EST Mars 34' N of Uranus
Mar. 1 Wed. 10:00 PM EST Neptune @ solar conjunction
Mar. 12 Sun. 2:00 AM EST Daylight Saving Time begins
Mar. 20 Mon. 6:29 AM EDT March Equinox
Mar. 25 Sat. 6:00 AM EDT Venus @ inferior conjunction
Apr. 1 Sat. 6:00 AM EDT Mercury @ greatest eastern elongation (19.0° E); Evening "Star"
Apr. 7 Fri. 5:00 PM EDT Jupiter @ opposition
Apr. 12 Wed. 2:00 PM EDT Comet 41P/Tuttle-Giacobini-Kresak @ perihelion (mag. 5?)
Apr. 14 Fri. 2:00 AM EDT Uranus @ solar conjunction
Apr. 22 Sat. 8:00 AM EDT Lyrid meteors
Apr. 22 Sat.   Cassini Titan flyby begins Proximal Orbit Phase ("Grand Finale")
Apr.29 Sat. All day Astronomy Day (spring)
Apr. 30 Sun. 12:00 AM EDT Venus @ greatest illuminated extent
May 4 Thur. 9:00 AM EDT Eta Aquarid meteors
May 17 Wed. 7:00 PM EDT Mercury @ greatest western elongation (25.8° W); Morning "Star"
Jun. 2 Fri. 10:00 AM EDT Venus 2° S of Uranus
Jun. 3 Sat. 7:00 AM EDT Venus @ greatest western elongation (45.9° W); Morning "Star"
Jun. 3 Sat. 8:00 PM EST Moon 2° N  of Jupiter
Jun. 3 Sat. 10:24 PM EDT - 12:21 AM EDT Double shadow transit on Jupiter (Io, Ganymede)
Jun. 12 Wed. 4:00 AM EDT Comet C/2015 V2 (Johnson) @ perihelion (mag. 6?)
Jun. 14 Wed. 5:07:00 AM EDT Earliest sunrise of year in Boston
Jun. 15 Thur. 5:00 AM EDT Saturn @ opposition
Jun. 19 Mon. 10:06 PM EDT - 10:38 PM EDT Double shadow transit on Jupiter (Io, Europa)
Jun. 21 Wed. 12:25 AM EDT June Solstice
Jun. 27 Tue. 8:25:22 PM EDT Latest sunset of year in Boston
Jul. 3 Mon. 4:00 AM EDT Earth @ aphelion (1.01668 AU / 152,093,193 km / 94,506,329 mi)
Jul. 10 Mon. 12:10 AM EDT Pluto @ opposition
Jul. 26 Wed. 9:00 PM EDT Mars @ superior comjunction
Jul. 28 Fri. 9:00 PM EDT Moon 2° N of Jupiter
Jul. 30 Sun. 12:00 AM EDT Mercury @ greatest eastern elongation (27.2° E); Evening "Star"
Aug. 7 Mon. 11:50 AM EDT - 4:50  PM EDT Partial Lunar Eclipse (Eastern Hemisphere)
Aug. 12 Sat. 3:00 PM EDT Perseid meteors
Aug. 21 Mon. 11:46 AM EDT - 5:04 PM EDT Total Solar Eclipse (Partial 9:28 AM EDT - 11:59 PM EDT in Boston)
Sept. 5 Tue. 12:00 AM EDT Neptune @ opposition
Sept. 12 Tue. 6:00 AM EDT Mercury @ greatest western elongation (17.9° W); Morning "Star
Sept. 15 Fri. 8:07 AM EDT Cassini enters atmosphere of Saturn, burns up
Sept. 16 Sat. 2:00 PM EDT Mercury 0.03° N of Mars (3.2' in Pacific, 18' in Boston)
Sept. 22 Fri. 4:02 PM EDT September Equinox
Sept. 23 Sat.   OSIRIS_REx Earth flyby
Sept. 30 Sat. All day Astronomy Day (fall)
Oct. 5 Thur. 9:00 AM EDT Venus 0.2° N of Mars
Oct. 7 Sat.   Mars @ aphelion
Oct. 19 Thur. 1:00 PM EDT Uranus @ opposition
Oct. 26 Thur. 2:12 PM EDT Jupiter @ solar conjunction
Nov. 5 Sun. 2:00 AM EDT Daylight Saving Time ends
Nov. 5 Sun. 9:03 PM EST - 9:59 PM EST Moon occults Aldebaran
Nov. 13 Mon. 1:00 AM EST Venus 0.3° N of Jupiter
Nov. 17 Fri. 12:00 PM EST Leonid meteors
Nov. 23 Thur. 7:00 PM EST Mercury @ greatest eastern elongation (22.0° E); Evening "Star"
Nov. 28 Tue. 5:00 AM EST Mercury 3° S of Saturn
Dec. 8 Fri. 4:11:42 PM EST Earliest sunset of year in Boston
Dec. 14 Thur. 1:00 AM EST Geminid meteors
Dec. 21 Thur. 11:29 PM EST December Solstice
Dec. 21 Thur. 6:00 PM EST Saturn @ solar conjunction
Dec. 22 Fri. 10:00 AM EST Ursid meteors
Dec. 30 Sat. 7:28 PM EST - 8:21 PM EST Moon occults Aldebaran




    Supernova Style Science News  with Ms. Julie Seven Sage



August 15, 2017 - 10:00 PM EDT