March/April 2017 – Vol. 29 No. 6

Celestial Highlights for May and June 2016

Posted: Wednesday, May 11th, 2016

by Robert C. Victor. Twilight sky maps by Robert D. Miller. Planet rising and setting graphs by Jeffrey L. Hunt

Make necessary preparations to safely observe the transit of Mercury across the Sun on May 9. Jupiter is brightest “star” in evening sky this spring until Mars offers serious competition in late May, as the Red Planet presents its brightest and closest approach since 2005. Mars-Saturn-Antares triangle expands in size and rises earlier in evening as weeks pass. Moon-Jupiter pair up on May 14, and a “Blue Moon” and Red Mars at its brightest, team up on May 21. Provide your students chances in May and June to get close-up telescopic views of all three bright outer planets!

On our chart depicting the sky at evening mid-twilight in May, we find two bright stars, Rigel south of west, and Aldebaran in WNW, leaving the scene early in the month – they may have already departed by the date you receive this. The brightest star, Sirius, the Dog Star, is the next to go, in the WSW. Then all that will remain of the Winter Hexagon will be the “Spring Arch” of Procyon, Pollux (with Castor 4.5 degrees to its right, not shown), and Capella. Orion’s shoulder Betelgeuse, sheltered under the Arch, drops out by late May, soon after Sirius.

On the chart, bright Jupiter follows Regulus across the sky’s vertical north-south-overhead line – the meridian (Sun’s midday line) – crossing it high in the south. Golden Arcturus climbs high in the east, while blue-white Spica is in SE, climbing toward the south. In the SE, Mars first appears in evening mid-twilight around midmonth – and competes with Jupiter in brilliance — while Saturn and Antares follow about a week later. But you can see Mars, Saturn, and Antares earlier in May, simply by observing later in the evening, or before dawn.

Off in the northeast in May’s evening twilight, bright blue-white Vega appears, followed by fainter Deneb. Altair, south point of the Summer Triangle, first graces our evening twilight scene in June.

For illustrations of the following sky events in May, you are encouraged to download and reprint the free May 2016 Sky Calendar and evening sky map available at

A graph of the rising and setting times of the planets for southern California may be found here.

May 6: New Moon 12:30 p.m. PDT.

May 7: At dusk, look for first young Moon, age 31-32 hours, very low in WNW. Aldebaran, eye of Taurus the Bull, just to upper left, beautiful in binoculars! On May 8, Moon will be higher, to upper left of Aldebaran.

May 9: Transit of Mercury visible in California from sunrise until 11:42 a.m. PDT. For details and links on how to observe the event safely, see article in April California Classroom Science < link >.

May 10, 11: From one evening to the next, Moon leaps over the line joining Pollux and Procyon.

May 13: Moon, just past First Quarter phase (half full and 90° from the Sun) in afternoon and evening sky. Whenever the Moon is close to half full in a blue daytime sky, you can install a single polarizing filter in your telescope’s low-power eyepiece and then rotate the eyepiece to darken the sky, improving contrast of Moon against sky. This evening, note Regulus, heart of Leo, above the Moon.

May 14: Using binoculars a few minutes before sunset, can you spot Jupiter not far upper left of the Moon? This evening, you can’t miss it! Saturday, May 14 is ASTRONOMY DAY. Visit to find a club, planetarium, or observatory and participate in their activities.

May 15-21: This week, Mars, going west 1/3 of a degree per day against background stars, passes closely N of Delta, brightest and middle star of three in the head of Scorpius. Two hours after sunset, Mars is the brilliant reddish object low in SE. Use binoculars, and you’ll notice Mars’ changing position with respect to Delta Sco from one evening to the next

May 17, 18: The bright star near the Moon is Spica, in Virgo.

May 21: The Full “Blue Moon” and red Mars hang out together from dusk until dawn. In spring 2016, we have four Full Moons: On Mar. 23, Apr. 21, May 21, and Jun. 20. The third Full Moon of four within the same astronomical season is called a “Blue Moon”:

So tonight’s Full Moon, the third of four this spring, is a “Blue Moon”.

May 21: Mars at opposition. Tonight, as Earth overtakes Mars, we observe the red planet all night long, from dusk to dawn, in the direction opposite to the Sun. Today’s Full “Blue Moon” rises in ESE around sunset, with Mars quickly becoming visible 6°-7° to Moon’s right. Within two hours after sunset, below Moon and Mars, look for Saturn with the twinkling red first-magnitude star Antares, “Rival of Mars”, about 7.5° to Saturn’s right. For the rest of the night, these four bright objects form a striking quadrilateral, in clockwise order, Moon, Mars, Antares, Saturn. The two planets lie at the ends of the longer diagonal. Best viewing time lasts from about two hours after sunset on Sat. May 21, until 1.5 hours before sunrise on Sun. May 22. Also that night, for skywatchers in California, Syrtis Major, the most prominent of the dark markings on Mars, lies near the center of the Martian disk as the planet reaches its highest position in the southern sky, when viewing is best. For more on observing surface features of Mars, see the April issue of California Classroom Science.

If you’re inclined to observe the predawn sky at this time of year, despite the very early sunrises, you’ll find the triangle of Mars, Saturn, and Antares sinking into the southwest, Arcturus in W to WNW, the Summer Triangle of Vega, Altair, and Deneb overhead, Fomalhaut low in SE, and, by June, Capella rising in far NE. In early June, Mercury reaches the peak altitude of an unfavorable morning apparition very low in ENE . Follow the Moon in the morning sky during May 22-June 3, and on the last day binoculars will show a thin old crescent Moon tucked just below Mercury half an hour before sunrise.

On the night of June 2, Earth passes between Sun and Saturn, and the ringed planet appears at opposition. An hour after sunset, find Saturn low in SE to lower left of Mars and upper left of Antares. Earth has now overtaken all three bright outer planets within three months, an event which hasn’t occurred since 1984. It’ll happen again in 2018, from May through July!) Now all three bright outer planets will adorn the sky at dusk until Jupiter sinks into the western twilight glow near the end of August 2016.

New Moon occurs on June 4 at 8:00 p.m. PDT. By the evening of June 6, the nearly 2-day-old crescent will be easy to spot low in WNW in twilight. Follow the waxing Moon. On June 7, it’s to lower left of the Twins, Pollux and Castor. Very low in W to Moon’s lower left, can you still spot Procyon, the Little Dog star? During June 9-11, watch the Moon march past Regulus and Jupiter. By June 11, the Moon has nearly reached First Quarter phase.

On June 14 the waxing gibbous Moon is near Spica in Virgo. During June 16-18, the Moon hops past Mars, Antares, and Saturn. By now the gap between Mars and Saturn has widened to 18°, with Mars having retrograded well to the west of the head of Scorpius. The Moon is Full overnight on June 19-20, actually at 4:02 a.m. PDT on the morning of June 20. Summer begins 11.5 hours later that day, with the solstice at 3:34 p.m.

Robert C. Victor was Staff Astronomer at Abrams Planetarium, Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs.

Robert D. Miller, who provided the twilight charts and the planet orbit charts, did graduate work in Planetarium Science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy.

Dr. Jeffrey L. Hunt, a retired planetarium director now living in the Chicago area, has taught astronomy and sky watching to all ages.  He studied astronomy education at Abrams Planetarium at Michigan State University. Jeff writes an astronomy blog at and can be followed on Twitter at @jeff_hunt.

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Written by Robert Victor

Robert Victor

Robert C. Victor was Staff Astronomer at Abrams Planetarium, Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs, CA. Robert is a member of CSTA.

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CSTA Endorses March for Science

Posted: Monday, March 27th, 2017

The California Science Teachers Association (CSTA) stands with our science and science education colleagues in endorsing the March For Science and its associated activities.

The decision by the CSTA Board of Directors to support the March for Science was based on the understanding that this is an opportunity to advocate for our mission of high quality science education for all and to advance the idea that science has application to everyday life, is a vehicle for lifelong learning, and the scientific enterprise expands our knowledge of the world around us. The principles and goals of the March for Science parallel those of CSTA to assume a leadership role in solidarity with our colleagues in science and science education and create an understanding of the value of science in the greater community. CSTA believes that the integrity of the nature of science and that the work of scientists and science educators should be valued and supported. We encourage your participation to stand with us.

There are over 30 satellite marches planned for the April 22, 2017 March for Science in California (to find a march near you, click on “marches” in the upper right of the main page, select “satellite marches” and use the search feature). We encourage members who participate in the March for Science to share their involvement and promotion of science and science education. Feel free to promote CSTA on your signs and banners. For those on social media, you may share your involvement via Twitter, @cascience and our Facebook groups.

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

California Science Curriculum Framework Now Available

Posted: Tuesday, March 14th, 2017

The pre-publication version of the new California Science Curriculum Framework is now available for download. This publication incorporates all the edits that were approved by the State Board of Education in November 2016 and was many months in the making. Our sincere thanks to the dozens of CSTA members were involved in its development. Our appreciation is also extended to the California Department of Education, the State Board of Education, the Instructional Quality Commission, and the Science Curriculum Framework and Evaluation Criteria Committee and their staff for their hard work and dedication to produce this document and for their commitment to the public input process. To the many writers and contributors to the Framework CSTA thanks you for your many hours of work to produce a world-class document.

For tips on how to approach this document see our article from December 2016: California Has Adopted a New Science Curriculum Framework – Now What …? If you would like to learn more about the Framework, consider participating in one of the Framework Launch events (a.k.a. Rollout #4) scheduled throughout 2017.

The final publication version (formatted for printing) will be available in July 2017. This document will not be available in printed format, only electronically.

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

Call for CSTA Awards Nominations

Posted: Monday, March 13th, 2017

The 2017 Award Season is now open! One of the benefits of being a CSTA member is your eligibility for awards as well as your eligibility to nominate someone for an award. CSTA offers several awards and members may nominate individuals and organizations for the Future Science Teacher Award, the prestigious Margaret Nicholson Distinguished Service Award, and the CSTA Distinguished Contributions Award (organizational award). May 9, 2017 is the deadline for nominations for these awards. CSTA believes that the importance of science education cannot be overstated. Given the essential presence of the sciences in understanding the past and planning for the future, science education remains, and will increasingly be one of the most important disciplines in education. CSTA is committed to recognizing and encouraging excellence in science teaching through the presentation of awards to science educators and organizations who have made outstanding contributions in science education in the state and who are poised to continue the momentum of providing high quality, relevant science education into the future. Learn More…

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

Call for Volunteers – CSTA Committees

Posted: Monday, March 13th, 2017


CSTA is now accepting applications from regular, preservice, and retired members to serve on our volunteer committees! CSTA’s all-volunteer board of directors invites you to consider maximizing your member experience by volunteering for CSTA. CSTA committee service offers you the opportunity to share your expertise, learn a new skill, or do something you love to do but never have the opportunity to do in your regular day. CSTA committee volunteers do some pretty amazing things: Learn More…

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

A Friend in CA Science Education Now at CSTA Region 1 Science Center

Posted: Monday, March 13th, 2017

by Marian Murphy-Shaw

If you attended an NGSS Rollout phase 1-3 or CDE workshops at CSTA’s annual conference you may recall hearing from Chris Breazeale when he was working with the CDE. Chris has relocated professionally, with his passion for science education, and is now the Executive Director at the Explorit Science Center, a hands-on exploration museum featuring interactive STEM exhibits located at the beautiful Mace Ranch, 3141 5th St. in Davis, CA. Visitors can “think it, try it, and explorit” with a variety of displays that allow visitors to “do science.” To preview the museum, or schedule a classroom visit, see Learn More…

Written by Marian Murphy-Shaw

Marian Murphy-Shaw

Marian Murphy-Shaw is the student services director at Siskiyou County Office of Education and is CSTA’s Region 1 Director and chair of CSTA’s Policy Committee.