September/October 2017 – Vol. 30 No. 1

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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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.

News and Happenings in CSTA’s Region 1 – Fall 2017

Posted: Tuesday, August 29th, 2017

by Marian Murphy-Shaw


This month I was fortunate enough to hear about some new topics to share with our entire region. Some of you may access the online or newsletter options, others may attend events in person that are nearer to you. Long time CSTA member and environmental science educator Mike Roa is well known to North Bay Area teachers for his volunteer work sharing events and resources. In this month’s Region 1 updates I am happy to make a few of the options Mike offers available to our region. 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.