Plot the amount of light detected by a spacecraft as it observes a planet transiting a star.

Background: There are several ways to find new planets.  First, scientists can sometimes measure the wobble of the parent star caused by the gravity of the hidden offspring planet.  Second, they can detect a Doppler shifting of the star's light spectrum as the orbiting planet repeatedly moves toward us, then away.  Third, they can look for dips in brightness that reveal planets blocking out a little light as the planets orbit the star within our plane.

The Kepler spacecraft is monitoring over 150,000 stars simultaneously as it looks for planets around distant stars. For comparison, imagine looking down from a skyscraper at 150,000 streetlights that are miles away and you hope to see some gnats flying in front of a few lights. If the insect passes in front of the streetlight along your line of sight, the amount of light you see will dip by a minute amount.  It may be too little for your eyes to notice, but the spacecraft is capable of discerning such small dips in brightness.

In this activity, the light from a star covers several pixels on a simulated computer chip.  From afar, the star would appear as a mere point of light, but the closer you get the more you can see and count distinct pixels.  For simplicity, students will count the number of pixels that reach the sensor for the duration of a transit.  A recurring, periodic dip in brightness suggests a planet is orbiting the host star, whereas a random dip in brightness may indicate any object, such as a nearby asteroid in our own solar system, is intersecting the light path between the star and the spacecraft. 

To Do:  Print or display the 15 snapshots, left, of a transit.  On graph paper, plot the numbers of yellow squares (y-axis) per unit of time (x-axis).  You may want to begin with multiple t=0 pixel counts to show the normal state of the scene with no transit, from which the curve can begin.  The units of time are not defined for this activity, but a transit may last for several hours. Compare the graph derived by the students with actual data from a transit, right.  To speed up the activity in a class, assign each kid the t=0 time frame just to make sure they are all on the same track.  Then have the kids choose a partner to count the lone second snapshot you designate for them. 

Read more: Activity: Pixel Count

By Roy Bishop; from the 2012 Observer's Handbook of the Royal Astronomical Society of Canada (RASC)

From the third planet, only Mercury and Venus can be seen silhouetted against the Sun. When an inferior conjunction takes place, the appreciable orbital inclinations of Mercury and Venus usually cause them to pass north or south of the solar disk and no transit occurs. Transits are uncommon for Mercury, rare for Venus. During the 20th century, there were 14 transits of Mercury, and 0 transits of Venus. Currently, transits of Venus occur in pairs, with 8.0 years separating the members of a pair, and the pairs separated alternately by 105.5 and 121.5 years, resulting in a 243.0-year period for the pattern.

Johannes Kepler, extraordinary astronomer and author of the Rudolphine Tables of planetary positions, predicted the Venus transit of 1631. Unfortunately, he died in 1630. Jeremiah Horrocks and his friend William Crabtree, in England, were the first to see a transit of Venus, on 1639 Dec. 4. Beginning with the transit pair in that century, years having Cytherean transits include:

Read more: RASC 2012 Transit of Venus

Destined to be a highlight of 2012 is the TROVE Art Exhibit, which celebrates the transit of Venus experience, past and future.  Artists working in any two-dimensional media are invited to create works that have relevance to the transit of Venus, a celestial phenomenon both with a rich history in the quest to understand our place in the solar system and with a modern role in the hunt for new worlds around distant stars. The 2012 alignment of earth, Venus, and the sun on June 5 is the last transit of Venus in our lifetimes, not occurring again until December 2117.  

TROVE (for TRansit Of VEnus) is a collection of regional attractions that complement this historic astronomical event. The venue for the TROVE Art Exhibit is the mezzanine gallery at The Livery, a microbrewery in the Arts District of Benton Harbor, Michigan.  Enjoy this unique art space while quaffing a hand-crafted Venusian ale.  The exhibit will be open seven days a week from May 6 until June 30, with a special party after sunset on June 5, 2012.  Please join the multiple TROVE celebrations, whether by sharing your vision through the creation of art, or by embracing science and math in action as a supporter of the arts.

Call for Art

Artists are invited to create works related to Venus, the sun, astronomy, exoplanets, transit math, historical expeditions, gods and goddesses, the black drop effect, and other notions with a connection to the solar spectacle.  Please state your intent to participate by April 15, and deliver your artwork to the site on May 5.  Art must be ready to hang and may be sold with no commission. Insurance is the artist's responsibility.  There is a $5.00 entry fee.  Please fill out one entry form for each submission (limit two):

2012T0V-Call-for-Artists.pdf (PDF)
2012T0V-Call-for-Artists.docx  (MS Word)

Dayle Brown, author and illustrator of Skylore from Planet Earth: stories from around the world...VENUS, has generously stepped up to coordinate the TROVE Art Exhibit.  You can contact Dayle Brown at 574-217-8557, or by email at dayledavid @ comcast .net (with no spaces).

Coming Soon: Beer Art

The history, mystique, and promise of the transit of Venus has a parallel storyline with beer.  The brewmaster at The Livery is crafting a special golden ale to commemorate the 2012 transit of Venus. 

Read more: Transit of Venus (TROVE) Art Exhibit

Jay Ryan has been steadfast in producing high-quality illustrations of the night sky that succinctly convey the appearance and the motion of celestial bodies.  Fifteen years ago he depicted the alignment of Earth, Venus, and the sun from the perspective of an observer outside Earth's orbit, clearly explaining the circumstances that yield two transits of Venus in eight years.  As the 2012 transit of Venus approaches, Ryan is again on the scene with his new illustrated guide Celestial Almanack.  While his target audience is Christian homeschoolers, Celestial Almanack will be a valuable reference for all observers of the night sky who want a timely guided tour of the heavens. 

The inaugural issue from January 2012 sets the stage for everyone who notices the bright object in the western sky after sunset.  For Ryan, a goal is to get people to watch the celestial dynamics unfold over time.  The 2012 transit of Venus experience begins well before June 5 or 6.

"I’m concerned that most people never even bother to notice Venus, even when it’s blazing bright as the evening star," Ryan said.  I’m trying to get people to notice Venus beforehand, and learn a bit about its synodic cycle.  This way, they can spot Venus in evening sky through the winter and spring and then watch it disappear into the sunset.  Then when they see the actual transit in June, they have some context and hopefully more appreciation for the big picture of Venus’ motions."

High quality illustrations are evident in the free preview of the Celestial Almanack, and when you download and see the complete version you will find much that satisfies for $3.00.  Stellar activities...

Read more: The Sky for Homeschoolers & Beyond

http://transitofvenusproject.com/
Transit of Venus is self-described as "Some kind of Glam Indie Pop Rock thing."  Download the free Morning Star soundtrack to the transit of Venus trailer (to be released mid-January 2012).  Also in production (as of August 2010) is new album that features LeGentil and fictional account of his wife.  Several songs and video available for free download, with more for sale.

http://lcweb2.loc.gov/diglib/ihas/html/venus/venus-home.html
Music and literature, with emphasis on John Philip Sousa.  The Library of Congress section 'Browse Materials' has three links to

1. Score/parts, audio, sheet music.  Contains sound recording performed by the Virginia Grand Military band in 2003 with Loris Schissel conducting; Transit of Venus March 1883 notated music with original 1883 scoring and instruments; and and Transit of Venus March notated music, an updated arrangement of Sousa's original 1883 score so that this march could be played on modern instruments. This score is a 12-page scoring in 23 parts and is available as a PDF file directly at the following URL http://lcweb2.loc.gov/natlib/ihas/service/transit/100010996/100010996.pdf. Thanks go to the IMAGE satellite E&PO program and to Mr. Loris Schissel and Susan Clermont at the Performing Arts Reading Room. 
   
2. Essay by Dr. Sten Odenwald about the significance of the transit of Venus.
3. Related materials, including 12 additional transit-related music resources.
   
   

The original music page from 2004 Sun-Earth Day is at http://sunearth.gsfc.nasa.gov/sunearthday/2004/vt_edu2004_venus_back_mus.htm


http://youtu.be/-rNQFUqt49Q
Penn High School Orchestra performs John Philip Sousa's Transit of Venus March in 2004.

/education/the-arts/149-song-mackey
Song by New Zealand folksinger Willow Mackey, which she composed for 1969 bicentennial of James Cooks voyage.  From Guy Ottewell.  Musician Matt Rumley records Ballad of James Cook, from the words and music of Willow Mackey.  Art Gorman and Jeff Tuholski also perform Young James Cook.


http://lcweb2.loc.gov/diglib/ihas/html/venus/venus-othermusic.html
Collection of other 18th and 19th century music related to the transit of Venus.  From Library of Congress, Music Division.

http://www.transitvenus.com/
Two New York musicians release 2008 album for free download under the band name Transit Venus.

Read more: Links: Music