March/April 2017 – Vol. 29 No. 6

Jupiter, Saturn and More – Arrange a Sky-watch for Your Class!

Posted: Tuesday, May 6th, 2014

by Robert Victor and Robert D. Miller

May 2014 is an excellent month for teachers to offer sky-watching sessions for their students. For most of the month, as many as four naked-eye planets and a large number of bright stars will be visible simultaneously during evening twilight. The Moon will be visible daily at dusk for two weeks, as it makes its way from a thin crescent low in WNW on April 30 to a Full Moon rising in ESE shortly after sunset on May 14. Beginning on April 30, students and teachers are encouraged to watch the Moon pass the planets and five bright stars of the zodiac, and identify them by using the daily calendar illustrations or the monthly sky chart.

The circular all-sky chart (Planets and Bright Stars in Evening Mid-Twilight and Planets and Bright Stars in Morning Mid-Twilight) depicts the sky on May 15 about 1.5 hours after sunset from southern California, and 1.2 hours after sunset from the northern border of the state. For these maps for northern California stargazers, click here.

A Plethora of Planets

The four planets, in order from the west-northwest horizon to the east-southeast, are Mercury, Jupiter, Mars, and Saturn. Jupiter and Mars rank first and third in brightness among all star-like objects visible in May’s evening sky. Extend a line from Jupiter toward Mars and beyond, to the lower left of Mars, to find Saturn. Extend the line in the other direction, from Mars to Jupiter and beyond, to find Mercury near the WNW horizon in twilight during May. The near-alignment of the four planets in May’s evening sky is not a coincidence! It occurs because the orbits of the planets are nearly coplanar. Other bright objects are found far off that line, for example, Sirius, the brightest star (ranking second, after only Jupiter in May’s evening sky), is well south of the plane of the solar system. Some other bright stars, including Arcturus, Vega, and Capella, are all well to the north of the solar system’s plane. The first magnitude zodiacal stars Aldebaran in Taurus, Pollux in Gemini, Regulus in Leo, Spica in Virgo, and Antares in Scorpius all lie within a few degrees of the ecliptic (Earth’s orbit plane), so the Moon and planets (and the Sun) appear to pass by them regularly.



The Showpiece Planets

Jupiter and Saturn, when visible, are wonderful showpieces for telescopic viewing: Jupiter with its dark cloud belts and as many as all four of the satellites discovered by Galileo; and Saturn with its rings and largest satellite Titan. In 2010-2011, Jupiter and Saturn were in nearly opposite directions from Earth and seldom visible simultaneously. Now in May and early June 2014, we see the two giant planets about 120 degrees apart, and we can get excellent telescopic views at a convenient early hour of evening. Jupiter appears in Gemini, not far from the “Twin” stars Pollux and Castor. Saturn appears in Libra, near two third-magnitude stars whose names mean “southern claw” and “northern claw” of the Scorpion. The first-magnitude star Antares, marking the heart of Scorpius, rises to the lower left of Saturn.

In coming years…

Jupiter takes almost 12 years to make one trip around the Sun, compared to Saturn’s requiring nearly 30 years. So each year, on average, Jupiter moves about 30 degrees east, compared to Saturn’s 12 degrees. Consequently, Jupiter gains about 18 degrees per year on Saturn, and about every 20 years, Jupiter appears to overtake Saturn. The last time that happened was at their close pairing low in morning twilight on May 28, 2000. In late May 2014, Saturn appears about 120 degrees east (ahead) of Jupiter in the evening sky. Jupiter is gaining, and on the evening of December 21, 2020 a very special event will take place – Jupiter and Saturn will appear only 0.1 degree apart, their closest conjunction since 1623, the year Galileo’s The Assayer was published.

As a multi-year project, students will enjoy following Jupiter closing in on Saturn until December 2020. This year, they can both be very well seen in the early evening from early May until early June. At the start of this 5-week “window”, Saturn is low in the SE; at the end, Jupiter is sinking low into WNW.

In 2015, the window for good viewing of both Jupiter and Saturn in early evening will begin about two weeks later in May, and last until early July, a month later than this year.

In 2016 and 2017, prime time for viewing both Jupiter and Saturn in an early evening session will shift out of the traditional school year into the summer months: In 2016, from late May until late July; and in 2017, from early June to late August.

By 2018, the window for catching both giants in early evening will broaden to over three months long, from late June until late September, including the start of the school year.

In 2019, Jupiter and Saturn will be seen together in the early evening, some 30° to 20° apart, from early July until nearly the middle of November.

In 2020, the giants will be seen no more than a few degrees apart in the early evening sky from mid-July until late December, almost the entire latter half of the year. The entire autumn season will be especially dramatic, as Jupiter closes in on Saturn for their tightest pairing in nearly four centuries!

So, take advantage of the May-June 2014 opportunity, during this school year, to catch telescopic views of the two showpiece planets, Jupiter and Saturn, at a convenient hour of early evening.

Wishing you clear, dark skies! (Remember to arrange access to a darkened part of your school grounds.) Here are some highlights, week-by-week. See Abrams Planetarium Sky Calendar for illustrations of Moon near planets and bright stars.

Week of May 5-9: Best evenings for using binoculars and telescopes to view surface features on the Moon.

Week of May 12-16: The Full Moon rises just after sunset on May 14. The Moon rises just over an hour after sunset on May 15, brightening the sky before twilight ends. Moon rises over two hours after sunset on May 16, allowing a brief interval of very dark skies!

Week of May 19-22: Best week for Mercury, and for four bright planets simultaneously. With no Moon, the latter part of each session, after twilight ends, will be dark!

You may not want to schedule a session for Friday evening, May 23, the start of the Memorial Day weekend. Instead, suggest students and their families arrange to be in a dark place to watch for a possible strong meteor shower that night, especially between 11:30 p.m. PDT Friday and 1:00 a.m. PDT on Saturday. Remind the students to get up and out early on Sunday morning, May 25, to enjoy the close pairing of Venus and the old crescent Moon, best about one hour before sunrise.

Week of May 27-30: Sky is still dark and moonless at end of evening twilight. This week, Mercury begins its sharp fade. On evening of Friday, May 30, look for the innermost planet to the right of young crescent Moon very low in WNW, and far to lower right of Jupiter. Remind the students to look on the evenings of Sat. May 31 and Sun. June 1 to see the waxing crescent Moon near Jupiter.

Week of June 2-6: Another good set of dates for viewing Moon with binoculars and telescopes for surface details. Moon near Regulus, the heart of Leo, on June 3 and 4, and passes First Quarter phase, ideal for observation, on Thurs. June 5. On the weekend, the waxing gibbous Moon appears near Mars on Sat. June 7, and near Spica on Sun. June 8.

Week of June 9-13: Moon strongly brightens the evening sky this week, but if you’re observing during twilight, bright moonlight doesn’t matter. Mercury’s gone, but you can still see three planets at dusk: Saturn in SSE, near fat gibbous Moon on June 9 and 10, Jupiter low in WNW, and Mars nearly on a line from Jupiter toward Saturn, over two-thirds of the way toward Saturn. The Moon passes widely north of Antares, heart of Scorpius, on the evening of June 11, and is Full the next evening, Thursday, June 12.

After that, the next bright planet the Moon will encounter will be Venus, in a spectacular close pairing at dawn on Tuesday, June 24.

Related resources, available here.

Monthly evening and morning twilight charts, depicting only stars of first magnitude or brighter, and the five naked-eye planets.

Daily observation log sheet for recording sightings of bright stars and planets; may be especially helpful from mid-April until June for encouraging students to follow the seasonal disappearance of stars in the western sky at dusk.

Orbit charts of the inner four planets (out to Mars) and inner six (out to Saturn), with data tables for plotting the positions of the planets in their orbits. It might be fun to plot the current positions of the planets, paste the orbit charts onto a stiff piece of cardboard, and then, at an outdoor observing session, hold the chart so that its orientation matches the orientation of the actual solar system in the sky. Mounting the chart on the panhead of an adjustable tripod would work well for getting the orientations to match. Once the planets are plotted for the current date and the chart is oriented correctly, a line from the plotted Earth to each plotted planet should point to the actual planet in the sky!

Robert D. Miller 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 Endorses March for Science

Posted: Monday, March 27th, 2017

The California Science Teachers Association (CSTA) stands with our science and science education colleagues in endorsing the March For Science and its associated activities.

The decision by the CSTA Board of Directors to support the March for Science was based on the understanding that this is an opportunity to advocate for our mission of high quality science education for all and to advance the idea that science has application to everyday life, is a vehicle for lifelong learning, and the scientific enterprise expands our knowledge of the world around us. The principles and goals of the March for Science parallel those of CSTA to assume a leadership role in solidarity with our colleagues in science and science education and create an understanding of the value of science in the greater community. CSTA believes that the integrity of the nature of science and that the work of scientists and science educators should be valued and supported. We encourage your participation to stand with us.

There are over 30 satellite marches planned for the April 22, 2017 March for Science in California (to find a march near you, click on “marches” in the upper right of the main page, select “satellite marches” and use the search feature). We encourage members who participate in the March for Science to share their involvement and promotion of science and science education. Feel free to promote CSTA on your signs and banners. For those on social media, you may share your involvement via Twitter, @cascience and our Facebook groups.

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.

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.