March/April 2017 – Vol. 29 No. 6

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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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: