March/April 2017 – Vol. 29 No. 6

Celestial Highlights for May 2015

Posted: Tuesday, May 5th, 2015

by Robert Victor with twilight sky maps by Robert D. Miller

Winter’s bright stars are departing in the west. In early May, while Mercury is visible, four planets can be seen simultaneously at dusk. Evenings from now well into July, three showpiece planets are available for telescopic observation. Venus and Jupiter are closing toward their spectacular rendezvous at the end of June.

In May, four of the 15 stars of first magnitude or brighter visible from mid-northern latitudes begin their annual leaves of absence, Evening Mid_Twilight. In order of departure, they are Rigel, Aldebaran, Sirius, and Betelgeuse. In June, Procyon, Capella, and Pollux will follow. These seven stars include all the stars of the huge Winter Hexagon, with Betelgeuse inside. It’s enjoyable and relaxing to look for these stars within an hour after sunset on clear spring evenings and use the DailySkywatchLog  to keep a record of which stars are seen. Those who watch regularly are certain to notice the stars appearing lower each evening at the same stage of twilight and eventually dropping out of view.

This change is a direct consequence of Earth’s annual revolution around the Sun. Follow link at the end of this article to the activity “Modeling seasonal visibility of stars and visibility of the planets.”

As seen from Earth from late April through mid-July, the Sun appears to move from Aries through Taurus into Gemini, causing these zodiac constellations and their neighbors to sink into the evening twilight glow, and, after several weeks, to reappear in the eastern sky at dawn. (Exception: Far northern Capella emerges at dawn before it leaves the evening sky.)

The Moon and naked-eye planets provide additional spice for skywatchers. In early May 2015, observers can view as many as four planets simultaneously with unobstructed views toward WNW and ESE. During May’s first week, Mercury shines near mag. 0, and on May 6, reaches its greatest angular distance from the Sun this time around, 21°. Around that date, Mercury also attains its highest position for this year at dusk. The best time to find it may be about one hour after sunset; look about 22° lower right of brilliant Venus. Also on May 6, find bright Jupiter 45° to Venus’ upper left. On May 6, wait until 1.4-1.5 hours after sunset, when Mercury is just 3° up in WNW. Then turn around to find Saturn about the same height above the opposite horizon, in ESE. The lineup of four planets Mercury-Venus-Jupiter-Saturn will span 173° across the sky.

Look a couple of minutes earlier each evening until May 11, and then you’ll find Mercury and Saturn 5° above opposite horizons 1.2 hours after sunset. But by then Mercury has faded to mag. +1.0, and it will fade rapidly in following days.

Much easier than catching four planets simultaneously in May 2015 is viewing three, and you can do so in all of May and well into July! The span of Venus-Jupiter-Saturn starts out 159° long on May 1, shrinking through 150° on May 9, 135° on May 22, to 125° on May 31.Venus and Saturn, the endpoints of the lineup, are both 10° up 2.5 hours after sunset on May 1, improving to 23° up at a very convenient viewing time of 1.3 hours after sunset by end of May. [Data for southern California.]

As a wonderful bonus, these three planets are the most impressive for telescopic observation: Venus starting in gibbous phase, two-thirds full at the start of May, passing through half full in early June, through ever larger and thinner crescent phases as the planet draws closer to Earth; Jupiter, with its cloud belts, and its four bright satellites discovered by Galileo (as were the phases of Venus); and Saturn with its amazing rings, now 24° from edge-on!

Excellent views of these showpiece planets available evenings in May into July 2015 make this a superb time to schedule evening sky watching sessions – star parties! – at schools, parks, camps, and elsewhere folks gather outdoors.

If you haven’t been following the 5-months-long approach of Venus to Jupiter in the evening sky, start now! Venus-Jupiter are 50° apart on May 1, closing to 35° apart on May 16, and 20° on June 1. The gap between the two brightest planets continues to narrow, to 10° on June 14, to 5° on June 21, and only 1/3 of a degree apart on June 30. This spectacular pairing of Venus-Jupiter will provide a great chance to do public astronomy outreach for several evenings around their closest approach on June 30. Illustrations appear on the Abrams Planetarium Sky Calendar, June and July issues.

Some Moon and planetary events in evening sky in May and early June

Many of these events are illustrated on the Abrams Planetarium Sky Calendar. A downloadable pdf of the May issue with an evening sky map may be reprinted and distributed free of charge. Go to

On May 1 and 2 in evening twilight, watch the waxing gibbous Moon leapfrog past Spica. Full Moon occurs on the evening of May 3. On May 4-6 two hours after sunset, watch the waning gibbous Moon go past Saturn and Antares.

The Moon returns to early evening sky on May 19, as a thin crescent low in WNW, 21°-22° lower right of Venus. Two days later on May 21, Moon passes 9° lower left of Venus, which now forms an isosceles triangle with Gemini’s “Twin” stars Pollux and Castor. Jupiter is now 30° to Venus’ upper left. On May 23 the fat crescent Moon appears 6° lower left of Jupiter. Catch the half-full First Quarter Moon near Regulus on May 24, and a gibbous Moon near Spica on May 29.

On June 1, the nearly Full Moon appears in SE near Saturn and Antares, while Venus aligns with Pollux and Castor in WNW. That same evening, Jupiter appears 20° to Venus’s upper left, with just 29 days to go until their spectacular conjunction on June 30th!

On June 6 at dusk, Venus reaches greatest elongation, 45° from Sun. Now half full through telescopes, the planet is rounding the apparent end of its orbit as seen from Earth and is rapidly approaching us!

For more information on sky events in 2015, see these articles and activities.


(A selection of twilight sky charts for use during months of the best planet gatherings.)


(Scroll down to “Modeling seasonal visibility of stars and visibility of the planets.” Includes planet orbit charts, a data table for plotting planets, and an activity sheet with 15 questions on visibility of stars and planets in 2015-2016.)

 Robert D. Miller, who provided the twilight 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.

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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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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.

Learning to Teach in 3D

Posted: Monday, March 13th, 2017

by Joseph Calmer

Probably like you, NGSS has been at the forefront of many department meetings, lunch conversations, and solitary lesson planning sessions. Despite reading the original NRC Framework, the Ca Draft Frameworks, and many CSTA writings, I am still left with the question: “what does it actually mean for my classroom?”

I had an eye-opening experience that helped me with that question. It came out of a conversation that I had with a student teacher. It turns out that I’ve found the secret to learning how to teach with NGSS: I need to engage in dialogue about teaching with novice teachers. I’ve had the pleasure of teaching science in some capacity for 12 years. During that time pedagogy and student learning become sort of a “hidden curriculum.” It is difficult to plan a lesson for the hidden curriculum; the best way is to just have two or more professionals talk and see what emerges. I was surprised it took me so long to realize this epiphany. Learn More…

Written by Guest Contributor

From time to time CSTA receives contributions from guest contributors. The opinions and views expressed by these contributors are not necessarily those of CSTA. By publishing these articles CSTA does not make any endorsements or statements of support of the author or their contribution, either explicit or implicit. All links to outside sources are subject to CSTA’s Disclaimer Policy: