September/October 2017 – Vol. 30 No. 1

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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CSTA Is Now Accepting Nominations for Board Members

Posted: Friday, November 17th, 2017

Current, incoming, and outgoing CSTA Board of Directors at June 3, 2017 meeting.

Updated 7:25 pm, Nov. 17, 2017

It’s that time of year when CSTA is looking for dedicated and qualified persons to fill the upcoming vacancies on its Board of Directors. This opportunity allows you to help shape the policy and determine the path that the Board will take in the new year. There are time and energy commitments, but that is far outweighed by the personal satisfaction of knowing that you are an integral part of an outstanding professional educational organization, dedicated to the support and guidance of California’s science teachers. You will also have the opportunity to help CSTA review and support legislation that benefits good science teaching and teachers.

Right now is an exciting time to be involved at the state level in the California Science Teachers Association. The CSTA Board of Directors is currently involved in implementing the Next Generations Science Standards and its strategic plan. If you are interested in serving on the CSTA Board of Directors, now is the time to submit your name for consideration. 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.

State Schools Chief Tom Torlakson Announces 2017 Finalists for Presidential Awards for Excellence in Mathematics and Science Teaching

Posted: Wednesday, September 20th, 2017

SACRAMENTO—State Superintendent of Public Instruction Tom Torlakson today nominated eight exceptional secondary mathematics and science teachers as California finalists for the 2017 Presidential Awards for Excellence in Mathematics and Science Teaching (PAEMST).

“These teachers are dedicated and accomplished individuals whose innovative teaching styles prepare our students for 21st century careers and college and develop them into the designers and inventors of the future,” Torlakson said. “They rank among the finest in their profession and also serve as wonderful mentors and role models.”

The California Department of Education (CDE) partners annually with the California Science Teachers Association and the California Mathematics Council to recruit and select nominees for the PAEMST program—the highest recognition in the nation for a mathematics or science teacher. The Science Finalists will be recognized at the CSTA Awards Luncheon on Saturday, October 14, 2017. 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.

Thriving in a Time of Change

Posted: Wednesday, September 13th, 2017

by Jill Grace

By the time this message is posted online, most schools across California will have been in session for at least a month (if not longer, and hat tip to that bunch!). Long enough to get a good sense of who the kids in your classroom are and to get into that groove and momentum of the daily flow of teaching. It’s also very likely that for many of you who weren’t a part of a large grant initiative or in a district that set wheels in motion sooner, this is the first year you will really try to shift instruction to align to the Next Generation Science Standards (NGSS). I’m not going to lie to you, it’s a challenging year – change is hard. Change is even harder when there’s not a playbook to go by.  But as someone who has had the very great privilege of walking alongside teachers going through that change for the past two years and being able to glimpse at what this looks like for different demographics across that state, there are three things I hope you will hold on to. These are things I have come to learn will overshadow the challenge: a growth mindset will get you far, one is a very powerful number, and it’s about the kids. Learn More…

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Written by Jill Grace

Jill Grace

Jill Grace is a Regional Director for the K-12 Alliance and is President of CSTA.

If You Are Not Teaching Science Then You Are Not Teaching Common Core

Posted: Thursday, August 31st, 2017

by Peter A’Hearn 

“Science and Social Studies can be taught for the last half hour of the day on Fridays”

– Elementary school principal

Anyone concerned with the teaching of science in elementary school is keenly aware of the problem of time. Kids need to learn to read, and learning to read takes time, nobody disputes that. So Common Core ELA can seem like the enemy of science. This was a big concern to me as I started looking at the curriculum that my district had adopted for Common Core ELA. I’ve been through those years where teachers are learning a new curriculum, and know first-hand how a new curriculum can become the focus of attention- sucking all the air out of the room. Learn More…

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Written by Peter AHearn

Peter AHearn

Peter A’Hearn is the Region 4 Director for CSTA.

Tools for Creating NGSS Standards Based Lessons

Posted: Tuesday, August 29th, 2017

by Elizabeth Cooke

Think back on your own experiences with learning science in school. Were you required to memorize disjointed facts without understanding the concepts?

Science Education Background

In the past, science education focused on rote memorization and learning disjointed ideas. Elementary and secondary students in today’s science classes are fortunate now that science instruction has shifted from students demonstrating what they know to students demonstrating how they are able to apply their knowledge. Science education that reflects the Next Generation Science Standards challenges students to conduct investigations. As students explore phenomena and discrepant events they engage in academic discourse guided by focus questions from their teachers or student generated questions of that arise from analyzing data and creating and revising models that explain natural phenomena. Learn More…

Written by Elizabeth Cooke

Elizabeth Cooke

Elizabeth Cooke teaches TK-5 science at Markham Elementary in the Oakland Unified School District, is an NGSS Early Implementer, and is CSTA’s Secretary.