May/June 2017 – Vol. 29 No. 7

Celestial Highlights for May 2013

Posted: Wednesday, May 1st, 2013

by Robert Victor and Robert D. Miller

May 2013 has some very special sights involving members of our solar system.

(1) Jupiter in W to WNW and Saturn in SE can be seen simultaneously almost 20° above opposite horizons in deep twilight in early May, providing good telescopic views of Jupiter’s cloud belts and Galilean moons, and Saturn’s rings, within a single session. This chance to catch Jupiter and Saturn conveniently in evening twilight occurs before the end of the current school year. Each year from now until Jupiter overtakes Saturn in December 2020, the range of dates for viewing the two giant planets simultaneously in evening twilight will widen, but shift later in the calendar. So, take advantage of this month’s fine opportunity to share views of Jupiter and Saturn with your students!

(2) The Moon graces the sky in evening mid-twilight during May 10-24, while waxing from a very thin crescent low in WNW to lower left of Venus on May 10, to Full, low in ESE, on May 24. Follow this link to Sky Calendar for views of Moon passing planets and bright stars during the month, including Venus on May 10, Jupiter on May 11 and 12, and Saturn on May 22. Look early on Friday May 10, from a place with an unobstructed view: Twenty-five minutes after sunset, Moon and Venus are only 4°-5° up in WNW, with Moon appearing as a very thin crescent just 26-27 hours after New and within 2° lower left of Venus. This will be the first and closest of nine monthly pairings of Moon and Venus during that planet’s evening apparition ending in early January 2014. Most of these pairings will be wide, 6°-9° apart, except for May 10, less than 2°, and September 8, less than 3° apart at dusk.

As twilight fades on May 10, look for Jupiter 18° upper left of the Moon-Venus pair. Can you spot Aldebaran, eye of Taurus the Bull, 11° below Jupiter? On May 11, the Moon will be higher, appearing 5° above Aldebaran and 6° below Jupiter. On May 12, the waxing crescent will appear 7° upper left of Jupiter.

On May 14 and 15, the fat crescent Moon passes widely south of Gemini’s “twin” stars, Pollux and Castor, and on May 17, the First Quarter Moon, half full and 90° E of the Sun, passes widely south of Regulus, heart of Leo, the Lion

On May 18, just one week after Mercury passes behind the Sun, our solar system’s innermost planet can be spotted very low in evening twilight, half an hour after sunset. Find Venus very low in WNW, with Jupiter 10° to its upper left, and Mercury 5° to lower right, the three planets spanning 15°. Binoculars will provide a better view. Saturn is also visible in ESE. On this night the four planets Mercury-Venus-Jupiter-Saturn span an arc of 150° across the sky. Follow them in the WNW nightly and watch for wonderful changes in coming days and weeks. Venus and Jupiter, the two brightest, appear within 5° of each other during May 23-June 1.

On May 21, find Virgo’s brightest star Spica just 4° lower left of the waxing gibbous Moon. On May 22, Saturn is within 5° to the Moon’s upper left

On Friday, May 24 the Full Moon is unusually bright. For more on the Full Moon, see the May Sky Calendar, its left margin notes, and the link at the end of those notes.

(3) Most compact gathering of three planets, from Friday, May 24 through Wednesday, May 29 (six evenings): Venus, Jupiter, and Mercury fit within a 5° field of view of binoculars (permitting magnifications of up to about 10X to fit them all in), forming a trio. On Friday, May 24 at dusk, Mercury passes just 1.4° N (upper right) of Venus, with Jupiter less than 4° to Venus’ upper left. The most compact gathering occurs on Sunday, May 26 of Memorial Day weekend, when all fit into a field less than 3° across. On that evening, Mercury passes 2.4° to the upper right of Jupiter, with both planets 2° from Venus. Saturn is in SE, 135° from Venus. On Tuesday, May 28, the two brightest planets, Venus and Jupiter, appear closest, just over 1.0° apart.

Illustrations of the gathering of planets for each evening in the latter half of May are provided on the Sky Calendar.


Here is our monthly evening twilight chart, with descriptions following:

Evening Mid-twilight for May 2013

At the start of May in evening mid-twilight, the three brightest objects are: Yellowish Jupiter shining steadily just north of west; blue-white twinkling Sirius in SW; and golden Arcturus well up in the east. As weeks pass, Jupiter sinks almost all the way down to the WNW horizon and by May’s end is replaced by two planets emerging from the far side of the Sun and climbing above Jupiter.

For Los Angeles, Palm Springs, and other places near lat. 34° N, evening mid-twilight during May occurs about 42-46 minutes after sunset. For northern California, mid-twilight from lat. 40° N in May occurs about 47-52 minutes after sunset.

During May each year, the greatest number of stars of first magnitude or brighter can be viewed simultaneously during evening twilight. Early in May, after Vega has risen in the northeast and before Rigel sets between W and WSW, 11 of the 15 or 16 stars of first magnitude or brighter visible from California can be spotted.

We invite you and your students to use the accompanying evening twilight sky chart for May 2013 to identify up to four naked-eye planets and the brightest stars as they first appear after sunset. Three of the planets, Venus, Jupiter, and Mercury, will form a spectacular compact gathering May 24-29, all fitting within a binocular field no more than 5° across.

Try this evening twilight sky watching project: In May, in order, Rigel, Aldebaran, Sirius, and Betelgeuse will disappear into the western evening twilight glow, and in June, Jupiter quickly departs, followed by Procyon, Mercury, and Capella. Make a checklist of all the objects plotted on our May evening twilight sky map, including the naked-eye planets. Keep daily records of which objects you can see within an hour after sunset, and try to determine the first and last dates of visibility for each object.

The appearances and disappearance of stars occur on nearly the same dates each year (for a given latitude), and so the observations can be used to keep a calendar. As an example, ancient Egyptians used the first morning rising of Sirius to warn when the annual flooding of the Nile was about to occur. In current times, depending on your location, you shouldn’t do your spring planting until Sirius (or some other star) has left the early evening sky.

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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.

2 Responses

  1. Just to add a note on how unusual is the compact trio of Venus-Jupiter-Mercury of May 24-29. There are 14 more trios (three planets within a 5-degree field) before 2050. Of these, the very next one, of Ve-Ma-Ju in the morning sky in Oct. 2015, will be very favorable, over 30 degrees up in dawn mid-twilight. The use of daylight saving time in effect in October means that your students won’t have to get up too outrageoulsly early to see the gathering.

    But for the next *evening* trios when the planets are again more than 4 degrees up in mid-twilight, we’ll have to wait until August 2038 and Sept. 2040.

    They;; be some fairly good trios for observers with binoculars (3 to 4 degrees up in mid-twilight) in July 2036 at dusk and Nov. 2041 at dawn. Some very good morning gatherings, 7 to 10 degrees above eastern horizon, will occur in Oct.-Nov. 2040 and Dec. 2044.

    Five other gatherings will occur with the lowest planet only 1 or 2 degrees up in mid-twilight, and two others appear too close to the Sun to be seen.

    So, take advantage of this month’s opportunity to see three planets gather. It’ll be many years before your students have another chance to see a similar event in the evening sky.

  2. CORRECTION — The August 2038 gathering, involving the same three planets Mercury, Venus, and Jupiter as in this Memorial Day weekend’s evening trio, will actually occur in the MORNING SKY. So be sure your students don’t miss seeing the trio this weekend. If they do miss it, they’ll have to wait until at least September 2040 to see another trio as easily in the evening sky.

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CSTA Annual Conference Early Bird Rates End July 14

Posted: Wednesday, July 12th, 2017

by Jessica Sawko

Teachers engaged in workshop activity

Teachers engaging in hands-on learning during a workshop at the 2016 CSTA conference.

Don’t miss your chance to register at the early bird rate for the 2017 CSTA Conference – the early-bird rate closes July 14. Need ideas on how to secure funding for your participation? Visit our website for suggestions, a budget planning tool, and downloadable justification letter to share with your admin. Want to take advantage of the early rate – but know your district will pay eventually? Register online today and CSTA will reimburse you when we receive payment from your district/employer. (For more information on how that works contact Zi Stair in the office for details – 916-979-7004 or

New Information Now Available On-line:

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.

Goodbye Outgoing and Welcome Incoming CSTA Board Members

Posted: Wednesday, July 12th, 2017

Jill Grace

Jill Grace, CSTA President, 2017-2019

On July 1, 2017 five CSTA members concluded their service and four new board members joined the ranks of the CSTA Board of Directors. CSTA is so grateful for all the volunteer board of directors who contribute hours upon hours of time and energy to advance the work of the association. At the June 3 board meeting, CSTA was able to say goodbye to the outgoing board members and welcome the incoming members.

This new year also brings with it a new president for CSTA. As of July 1, 2017 Jill Grace is the president of the California Science Teachers Association. Jill is a graduate of California State University, Long Beach, a former middle school science teacher, and is currently a Regional Director with the K-12 Alliance @ WestEd where she works with California NGSS K-8 Early Implementation Initiative districts and charter networks in the San Diego area.

Outgoing Board Members

  • Laura Henriques (President-Elect: 2011 – 2013, President: 2013 – 2015, Past President: 2015 – 2017)
  • Valerie Joyner (Region 1 Director: 2009 – 2013, Primary Director: 2013 – 2017)
  • Mary Whaley (Informal Science Education Director: 2013 – 2017)
  • Sue Campbell (Middle School/Jr. High Director: 2015 – 2017)
  • Marcus Tessier (2-Year College Director: 2015 – 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.

Finding My Student’s Motivation of Learning Through Engineering Tasks

Posted: Wednesday, July 12th, 2017

by Huda Ali Gubary and Susheela Nath

It’s 8:02 and the bell rings. My students’ walk in and pick up an entry ticket based on yesterday’s lesson and homework. My countdown starts for students to begin…3, 2, 1. Ten students are on task and diligently completing the work, twenty are off task with behaviors ranging from talking up a storm with their neighbors to silently staring off into space. This was the start of my classes, more often than not. My students rarely showed the enthusiasm for a class that I had eagerly prepared for. I spent so much time searching for ways to get my students excited about the concepts they were learning. I wanted them to feel a connection to the lessons and come into my class motivated about what they were going to learn next. I would ask myself how I could make my class memorable where the kids were in the driver’s seat of learning. Incorporating engineering made this possible. Learn More…

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Written by NGSS Early Implementer

NGSS Early Implementer

In 2015 CSTA began to publish a series of articles written by teachers participating in the California NGSS k-8 Early Implementation Initiative. This article was written by an educator(s) participating in the initiative. CSTA thanks them for their contributions and for sharing their experience with the science teaching community.

State Schools Chief Tom Torlakson Unveils Updated Recommended Literature List

Posted: Wednesday, July 12th, 2017

SACRAMENTO—State Superintendent of Public Instruction Tom Torlakson unveiled an addition of 285 award-winning titles to the Recommended Literature: Prekindergarten Through Grade Twelve list.

“The books our students read help broaden their perspectives, enhance their knowledge, and fire their imaginations,” Torlakson said. “The addition of these award-winning titles represents the state’s continued commitment to the interests and engagement of California’s young readers.”

The Recommended Literature: Prekindergarten Through Grade Twelve list is a collection of more than 8,000 titles of recommended reading for children and adolescents. Reflecting contemporary and classic titles, including California authors, this online list provides an exciting range of literature that students should be reading at school and for pleasure. Works include fiction, nonfiction, poetry, and drama to provide for a variety of tastes, interests, and abilities. 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:

Teaching Science in the Time of Alternative Facts – Why NGSS Can Help (somewhat)

Posted: Wednesday, July 12th, 2017

by Peter A’Hearn

The father of one of my students gave me a book: In the Beginning: Compelling Evidence for Creation and the Flood by Walt Brown, Ph. D. He had heard that I was teaching Plate Tectonics and wanted me to consider another perspective. The book offered the idea that the evidence for plate tectonics could be better understood if we considered the idea that beneath the continent of Pangaea was a huge underground layer of water that suddenly burst forth from a rift between the now continents of Africa and South America. The waters shot up and the continents hydroplaned apart on the water layer to their current positions. The force of the movement pushed up great mountain ranges which are still settling to this day, resulting in earthquakes along the margins of continents. This had happened about 6,000 years ago and created a great worldwide flood. Learn More…

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Written by Peter AHearn

Peter AHearn

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