Welcome to the Boston Astronomy website ...

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.



A New Fall Astronomy Course!


Meet the Universe!


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, 7:45-9:15. Runs Sep. 27 - Nov. 15


For more info:




          July / August Astronomy-Related Events in the Boston Area  



Saturday, July 9th, 2016, at 8:45 PM EDT

Arlington Astronomy Nights

The planets continue their ride across the sky that will last most of the summer.  Jupiter has moved further West, tonight right beside a waxing crescent Moon and Mars and Saturn move into a place of prominence in the South.

Each Astronomy Night will start when the stars come out and usually lasts a couple hours. If it is overcast we'll have to cancel and hope for clear weather the follow night, but as long as there are some stars visible we'll give it a shot.  For reminders and weather decisions, consider joining my announcement mailing list.  Weather decisions for questionable nights will also be posted on this site.  Rain dates are the following night for each date. We set up the telescopes on the observation area of Robbins Farm Park that overlooks Boston.
Please note: it will be dark in the park!  Bring a flashlight, but please keep it aimed at the ground while you're in the park. Parents, please help your children remember this rule. It takes your eyes a while to adjust to the dark, and you'll see more in the sky once your night vision is working. Keeping your flashlight pointed at the ground helps everybody keep their eyes adjusted to the dark. Red light doesn't hurt night vision as much so a red flashlight or red cellophane over a flashlight helps a lot! Consider using bug spray too. If you have questions, feel free to contact me at



Saturday, July 9th - Thursday, July 14th.

Hokule'a Polynesian Canoe Wordwide Voyage - Boston Stopover

Fan Pier, Boston, MA

The Hokule'a, a canoe constructed and sailed according to traditional Polynesian methods, is stopping in Boston from July 9-14 as part of its world tour. A Polynesian crew has navigated the Hokule’a over 20,000 miles from Hawaii to New England coasts using only the stars to navigate as part of their mission to inspire communities to respect and care for their natural environments. The canoe and crew will participate in events with NOAA, Woods Hole Oceanographic Institution and the Museum of Science while here. They'll also showcase what makes the ship and its navigation techniques unique. Two thousand years ago, Ancient Polynesians traveled thousands of miles across open oceans and accurately navigated to distant islands, when explorers from most other cultures were still primarily sailing within sight of land. This lore is generally quite fascinating to the general public and especially people with an understanding of what it would mean to have to determine latitude without seeing Polaris. The public event schedule is as follows:

July 9 3pm-7pm - Fan Pier: Welcome ceremony: The Hōkūleʻa will be welcomed by representatives of the Massachusett Tribe and the Boston Hōkūleʻa Committee.
• July 10 10am-3pm - Fan Pier:
Outreach day: The Hōkūleʻa crew and supporting members will meet with local Native American communities, schools, maritime groups, and the general public offering activities including introductions to star compass navigation and canoe presentations

• On July 11 at 6pm-7:30pm - Harvard: Polynesian navigation lecture: the Harvard Graduate School of Design will host a talk-story session with senior crewmembers and navigators discussing the Hōkūleʻa’s worldwide voyage, Polynesian wayfinding, and ocean protection. Location: Piper Auditorium, Gund Hall, 48 Quincy Street, Cambridge, MA 02138
More information on the events and the ship can be found on our Facebook event page (please look out for the official press release and event flyer information from the Boston Hokule’a Committee being released soon) or at the Hokule’a website.



Thursday, July 14th, 2016, from 8:00 PM - 10:00 PM

Amateur Telescope Makers of Boston

Harvard-Smithsonian Center for Astrophysics

Our July Speakers:
Back by popular demand (and a voice vote from the membership at the June meeting) is our July Member Speaker Program. Among the home-grown talent presenting are Alan Sliski, his son Aaron, and Ken Launie, who will discuss their visits to Chile to review the redeployment of the APASS (AAVSO Photometric All-Sky Survey) telescope system. More info on this program can be gleaned from the AAVSO website at Club Secretary Phil Levine will talk about last April’s Nantucket Star Party and Mario Motta will cap things off with an update on his research into the wd1145 exoplanet. (TBA)


July 29 - Saturday, August 6, 2016

Summer Star Party
Peppermint Park Camping Resort
Plainfield, MA



Sunday, July 31 - Saturday, August 6, 2016

Medomak Astronomy Retreat
Washington, Maine
hosted by Kelly Beatty and Bruce Berger. 



Thursday, August 4 - Sunday, August 7, 2016

Springfield, VT

Featured speaker: Fred Espenak ("Mr. Eclipse") - The Great North American Eclipse of 2017.

A total eclipse of the sun will occur over a great swath of North America on August 21, 2017. Fred Espenak, a well known NASA Astrophysicist called Mr. Eclipse, will deliver our keynote address highlighting all aspects of this much anticpated solar alignment. Fred is an expert astrophotographer and will also give us information on the latest techniques to capture this event. Don't miss this timely talk direct from this important astrophysicist.

There will also be other talks, workshops, and numerous events, for both beginners and advanced amateurs, throughout the weekend.



Saturday, August 20th, 2016, at 8:30 PM EDT

Arlington Astronomy Nights

The Moon is below the horizon at dusk, keeping the sky as dark as we get in Arlington.  We'll look for some "deep sky" objects like star clusters, galaxies, and nebulas if we can spot them.  Jupiter is now setting at dusk, and Saturn and Mars have moved to the West, heading towards the same fate as the Earth continues its path around the Sun towards Autumn.     



Friday, August 26 - Saturday, August 27, 2016

Maine Star Party
Cobscook Bay State Park, Edmunds, Maine
Maine State Star Party




Plus (ongoing):  




Boston University

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




Fridays (every Friday, 8:30 PM)

Astronomy After Hours

Museum of Science, Boston, MA




The Sky Report for the Month of July 2016


The Earth is at aphelion – its furthest distance from the Sun – at noon EDT on July 4th The distance between the two bodies reaches its annual maximum: 94.5 million miles. (Recall that the heat of summer and the cold of winter seasons are caused not by Earth’s distance from the Sun but by its axial tilt.)


Current Night Sky: At A Glance


            Phases of the Moon:


New Moon

July 4

      7:01 AM EDT

First Quarter

July 11

8:52 PM EDT

Full Moon

July 19

6:57 PM EDT

Last Quarter Moon

July 26

7:00 PM EDT



The Moon & Planets:



Planet Visibility:


In Evening (after sunset):

    Venus, in W

    Mercury, in  W

    Jupiter, in W

    Mars, in S

    Saturn, in S



 At Midnight:

    Mars, in W

    Saturn, in W


 In Morning (before sunrise):

  •     Neptune, in S 

  •     Uranus, in SE





      •     Comet C/2013 X1 (PANSTAARS) starts July in the 6 – 7 magnitude range, but is very low in the southern sky for observers in the Northern Hemisphere; it gets higher but fades rapidly as the month goes on.


      •      The Southern Delta Aquariids peak on the night of July 29/30, but it is not a strong shower in the Northern Hemisphere; observers can expect to see about 8-10 meteors per hour.





    On the evening of the 14th, Mars, Saturn, Antares, and the waxing gibbous Moon form a rough trapezoid in the south.

    The two images below illustrate the appearance of the two planets through a telescope at this same moment.

    (July 14, 2016, 10:00 PM EDT).





    Mars is well past opposition, but is still conspicuous by virtue of its brightness and orange tint. At midmonth, it shines at magnitude -1.1, and presents a

    globe 14.6 arc-seconds in diameter. Though the planet is receding and shrinking, modest telescopes should still be able to reveal surface details. 

    (July 14, 2016, 10:00 PM EDT).





        Saturn is also past opposition; it is at magnitude +0.2 at midmonth, less than a third as bright as Mars..

    The globe of the planet is 18” across, while the visible rings measure 41” across.  

    (July 14, 2016, 10:00 PM EDT).





     The two innermost planets, Mercury and Venus, return to the evening sky this month. On the 16th, they are only a half degree apart, but they remain so low to the horizon that they are unlikely to be visible to most mid-Northern Hemisphere observers. By month’s end, however, both will have gained enough altitude to be routinely observable. A half an hour after sunset on the 31st, they form an almost-straight line with first-magnitude Regulus and – far above – Jupiter. 

    (July 31, 2016, 8:34 PM EDT).





              A Visitor to Jupiter


    Jupiter, of course, is the largest planet in our Solar System. Most people, however, have little conception of how large is truly is. Jupiter weighs in at 318 times Earth’s mass; the next largest body, Saturn, has a mass of “just” 95 Earth-masses. In fact, if you took all the planets in the Solar System except Jupiter and lumped them together, they would add up to less than half the mass of Jupiter.


    Jupiter has been known as a planet since ancient times, and the invention of the telescope in the 1600s allowed us to discover quite a bit about this “gas giant”. But, as often happens in science, hard-won knowledge leads to even more questions.


    It was not until interplanetary exploration began in earnest in the 1970s that we could see the outer planets like Jupiter close-up. To date, seven spacecraft have flown by the planet, and one – Galileo – spent more than seven years in orbit around it. But the questions remained.


    Among them were, “What is Jupiter made of?”, “Does it have a solid core?”, “What is the structure of the atmosphere?”, and “What accounts for the hugely extended magnetic field and the intense radiation belts?”.


    The next mission to Jupiter, Juno, was launched in 2011. It is set to arrive at Jupiter and insert itself into a polar orbit around the planet this July 4th. The mission will end in February of 2018; the spacecraft, having completed 37 orbits around the planet, will be commanded to deorbit and burn up in the planet’s dense atmosphere.




    Jupiter Orbit Insertion (JOI) will place the Juno spacecraft into a polar orbit around Jupiter, in order to avoid the powerful radiation belts near the planet’s equatorial regions. Over time, however, gravitational perturbations will inevitably bend the orbit to pass through more intense parts of the particle belts. Though some of the instrument package is protected inside a radiation-hardened titanium “vault”, the instruments will inevitably degrade or fail completely over time. (NASA/JPL)




    The Juno spacecraft will ultimately settle into an eccentric polar orbit around Jupiter, ranging out as far as 1.7 million miles from the planet,

    then diving to within 2,700 miles of the cloudtops. (NASA/JPL)




    Though we can map the complex structures in Jupiter’s cloudtops from Earth, we know the interior only from theoretical models. These suggest a solid core

    of rock and ice several times the mass of Earth, surrounded by metallic hydrogen, topped by a layer of liquid hydrogen just below the planet’s cloudtops.

    But other models suggest no solid core at all. Precise observations of Juno’s orbit will constrain key parameters of the models. (Kelvinsong, Wikimedia Commons)  




    Jupiter’s complex magnetic field traps charged particles in its deadly radiation belts. Some of the trapped particles travel along magnetic field lines to ionize the neutral atoms at the top of the planet’s atmosphere, causing auroral ovals over the north and south poles. Juno, the first spacecraft to fly over the polar regions, will have a ringside seat. (NASA/JPL)



    A Schedule of Events - July / August 2016
    July 1 Fri. 2:40 AM EDT Moon @ perigee (365,983 km / 227,411 mi)
    July 4 Mon. 7:01 AM EDT New Moon
    July 4 Mon. 12:00 PM EDT Earth @ aphelion (152,103,775  km. / 94,512,904 mi)
    July 4 Mon. 12:00 PM EDT Autumn equinox on Mars
    July 4 Mon. 11:18 PM EDT (ERT) Juno begins JOI burn
    July 4 Mon. 11:38 PM EDT (ERT) Juno capture into Jupiter orbit acheived
    July 4 Mon. 11:53 PM EDT (ERT) Juno ends JOI burn
    July 5 Tue. 1:48 AM EDT Juno Capture Orbit Phase begins (Perijove 0)
    July 6 Wed. 11:00 PM EDT Mercury @ superior conjunction
    July 7 Thur. 6:00 PM EDT Pluto @ opposition
    July 8 Fri.   5th Anniversary (2011) of last Space Shuttle launch (STS-135, Atlantis)
    July 9 Sat. 6:00 AM EDT Moon 0.9° of Jupiter
    July 11 Mon. 8:52 PM EDT First Quarter Moon
    July 13 Wed. 1:24 AM EDT Moon @ apogee (404,269 km / 251,201 mi)
    July 14 Thur. 2:00 PM EDT Moon 8° N of Mars
    July 16 Sat. 1:00 AM EDT Moon 3° N of Saturn
    July 16 Sat. 2:00 PM EDT Mercury 0.5° N of Venus (11° from Sun in evening sky, -1.0 & -3.9)
    July 19 Tue. 6:57 PM EDT Full Moon ("Full Buck Moon")
    July 20 Wed.   47th Anniversary (1969) of First Human Landing on Moon (Apollo 11)
    July 20 Wed.   40th Anniversary (1976) of First Mars Landing (Viking 1)
    July 20 Wed. 9:00 AM EDT Sun enters Cancer
    July 23 Sat. 12:07 AM EDT - 1:00 AM EDT Moon occults Neptune
    July 25 Mon. 12:00 AM EDT Moon 3° S of Uranus
    July 26 Tue. 7:00 PM EDT Last Quarter Moon
    July 27 Wed. 7:37 AM EDT Moon @ perigee (369,663 km / 229,698 mi)
    July 29 Fri. 6:19 AM EDT - 7:03 AM EDT Moon occults Aldebaran (daylight, Moon 23% illuminated)
    July 29 Fri.   Southern Delta Aquariid meteors peak (< 10 meteors / hour)
    Aug. 2 Tue. 4:45 PM EDT New Moon
    Aug. 4 Thur. 2:00 AM EDT Moon 3° S of Venus
    Aug. 4 Thur. 6:00 PM EDT Moon 0.6° S of Mercury
    Aug. 6 Sat. 12:00 AM EDT Moon 0.2° of Jupiter
    Aug. 9 Tue. 8:05 PM EDT Moon @ apogee (404,262 km / 251,197 mi)
    Aug. 10 Wed. 4:00 AM EDT Sun enters Leo
    Aug. 10 Wed. 2:21 PM EDT First Quarter  Moon
    Aug. 11 Thur. 6:00 PM EDT Moon 8° N of Mars
    Aug. 12 Fri. 8:00 AM EDT Moon 4° N of Saturn
    Aug. 12 Fri. 8:40 AM EDT Perseid meteors peak
    Aug. 12 Fri. 8:57 PM - 9:03 PM EDT Brightest ISS Pass in August (mag. -3.3)
    Aug. 16 Tue. 5:00 PM EDT Mercury @ greatest eastern elongation (27° W); Evening "Star"
    Aug. 18 Thur. 5:27 AM EDT Full Moon ("Full Sturgeon Moon")
    Aug. 19 Fri. 8:00 AM EDT Moon 1.1° N of Neptune
    Aug. 21 Sun. 9:19 PM EDT Moon @ perigee (367,050 km / 228,074 mi)
    Aug. 22 Mon. 6:00 AM EDT Moon 3° S of Uranus
    Aug. 24 Wed. 11:41 PM EDT Last Quarter Moon
    Aug. 25 Thur. 2:00 PM EDT Mars 4° S of Saturn
    Aug. 27 Sun. 6:00 PM EDT Venus 0.07° (4.2') N of Jupiter (closest appulse this year)
    Aug. 28 Sun. 12:00 AM EDT Mercury, Venus, Jupiter within circle 5.07° in diameter
    Aug. 28 Sun. 4:00 PM EDT Mercury 5° S of Venus


       (bold = cool or important)




    An Overview of Major 2016 Astronomical Events

    Jan. 2 Sat. 6:00 PM EST Earth @ perihelion (0.98330 AU)
    Jan. 3 Sun. 7:13 AM EST Latest sunrise
    Jan. 4 Mon. 3:00 AM EST Quadrantid meteors
    Jan. 19 Tue. 9:35 PM EST - 10:49 PM Moon occults Aldebaran
    Feb. 6 Sat. 0:00 (midnight) EST Mercury @ greatest western elongation (26° W); Morning "Star"
    Mar. 8 Tue. 5:00 AM EST Jupiter @ opposition
    Mar. 8 Tue. 7:17 PM EST - 10:38 PM EST Total Solar Eclipse (Pacific, SE Asia)
    Mar. 13 Sun. 2:00 AM EST Daylight Saving Time begins
    Mar. 14 Mon.   ESA ExoMars Trace Gas Orbiter / Schiaparelli EDL launch
    Mar. 19 Sat. 00:30 AM EST March Equinox
    Mar. 23 Wed. 5:37 AM EDT - 9:57 AM EDT Penumbral Lunar Eclipse
    Apr. 10 Sun. 6:52 PM EDT - 7:56 PM EDT Moon occults Aldebaran (daytime, late afternoon)
    Apr. 18 Mon. 8:00 AM EDT Mercury @ greatest eastern elongation (20° W); Evening "Star"
    May 5 Thur. 4:00 PM EDT Eta Aquariid meteor shower peaks
    May 9 Mon. 7:12 AM EDT - 2:42 PM EDT Transit of Mercury
    May 22 Sun. 7:00 AM EDT Mars @ opposition
    May 30 Mon. 4:00 PM EDT Mars @ closest approach
    June 3 Fri. 2:00 AM EDT Saturn @ opposition
    June 4 Sat. 3:41 PM EDT - 4:47 PM EDT Moon occults Aldebaran (daytime, close to Sun)
    June 5 Sun. 5:00 AM  EDT Mercury @ greatest western elongation (24° W); Morning "Star"
    June 6 Mon. 6:00 PM EDT Venus @ superior conjunction
    June 20 Mon. 6:00 PM EDT June Solstice
    June 26 Sun. 8:25 PM EDT Latest sunset
    July 4 Mon. 12:00 PM EDT Earth @ aphelion (1.01675 AU)
    July 4 Mon. 10:30 PM EDT (ERT) Juno Jupiter orbit insertion
    July 7 Thur. 12:00 PM EDT Pluto @ opposition
    July 23 Sat. 12:07 AM EDT - 1:01 AM EDT Moon occults Neptune
    July 29 Fri. 6:21 AM EDT - 7:03 AM EDT Moon occults Aldebaran (daytime)
    Aug. 12 Fri. 11:30 AM EDT Perseid meteors peak (ZHR 150), favoring central Pacific
    Aug. 16 Tue. 2:00 PM EDT Mercury @ greatest eastern elongation (27° W); Evening "Star"
    Aug. 27 Sat. 6:00 PM EDT Venus passes 4' from Jupiter (closest naked-eye planet conjunction)
    Sept. 1 Thur. 5:00 AM EDT Annular Solar Eclipse (Sothern Africa, Indian Ocean)
    Sept. 2 Fri. 1:00 PM EDT Neptune @ opposition
    Sept. 8 Thur. 3:00 PM EDT OSIRIS-Rex sample-return mission to asteroid Bennu launched
    Sept. 22 Thur. 10:21 AM EDT September Equinox
    Sept. 28 Wed. 3:00 PM EDT Mercury @ greatest western elongation (18° W); Morning "Star"
    Sept. 30 Fri.   Rosetta mission slow-mootion crash landing on Comet 67P.
    Oct. 15 Sat. 7:00 AM EDT Uranus @ opposition
    Oct. 16 Sun.   ExoMars TGO/Schiaparelli separation
    Oct. 19 Wed.   ExoMars TGO Mars orbit insertion
    Oct. 19 Wed.   ExoMars Schiaparelli Mars landing
    Oct. 19 Wed. 1:50 AM EDT - 2:54 PM EDT Moon occults Aldebaran
    Oct. 20 Thur. 9:00 PM EDT Ceres @ opposition
    Nov. 6 Sun. 2:00 AM EDT Daylight Saving Time ends
    Nov. 17 Thur. 6:00 AM EST Leonid meteroids
    Dec. 6 Tue. 11:18 PM EST - 12:32 AM EST Moon occults Neptune
    Dec. 10 Sat. 11:00 PM EST Mercury @ greatest eastern elongation (21° W); Evening "Star"
    Dec. 13 Tue. 7:00 PM EST Geminid meteors
    Dec. 21 Wed. 5:44 AM EST December Solstice
    Dec. 22 Thur. 4:00 AM EST Ursid meteors




    July 14, 2016




    July 14, 2016, 10:00 PM EDT