ae cern aos ast ononty calendar — ‘Stars over Terrace _ oe by Allen Wootton, Terrace contributer "TERRACE — This month I have some’star photos to -.... Sharé’with you. These photos were taken by Corinna “Adams -and “Heather Inglis, two students of Skeena * Junior Secondary in Terrace. “The photos show a.number of remarkable things. As well, they ‘may give you some ‘ideas ‘about the sort of | ° a photos ‘that ¢ can be obtained with even relatively simple ; equipment. . STAR TRAIL ARCS fo The f irst photo shows star trails. The photo w was taken oe “with-a single lens reflex camera that was mounted on a *, tripod. and loaded with a fast (ISO 400/27°) black and _ white film. (Color film can be used instead and then you can even see the different colors of stars.) 2’ The camera was aimed in the general area of Polaris, the ‘North Star’’, and the lens was set so that its open- “ing was at its maximum, Then a cable release was used «to trip the shutter of the camera and to hold it open for close to. two hours. While the camera sat out in the dark the Earth’s rotation turned the camera. As a result, in- stead of forming points on the film, the stars produced . ares that are centered ‘on Polaris. Unfortunately, Polaris is just out of the bottom left 7 corner of the picture so you cannot see that:it shows - ~ very little movement on the film (because it is almost in . line with the Earth’s axis). You can see, though, that the _ closer ; a star is to Polaris, the shorter the arc it produces. “ Notice that although the arcs are shorter for sta: s that : | ‘are ‘closer to Polaris, the number of degiees that the arc _ covers remains the same for all stars: This is because the ares are concentric with that formed by Polaris almost a exactly at the center. _ > With a little bit of calculation you. can even use these arcs ‘to check the time the camera shutter was held open. - . With a protractor I measured the arcs — my estimate is | that they cover about 24 degrees. Since a full circle has 360. degrees, 24 degrees corresponds to 24/360 or 1/15 . of acircle. The Earth takes just about 24 hours to make one rotation. Thus the 1/15 of a rotation represented in this circle took 1/15x24 hours or 1.6 hours, about | hour, 36 minutes. It is difficult to get. really good photos in which the camera shutter is held open for a much longer time. The * reason is that the longer you leave the camera open, the more that stray light affects the parts of the film where there are no stars. As a result, such photos show much ‘less contrast between the stars. and what should be a . dark « background, THE BIG DIPPER I am sure that you will recognize the ‘‘Big Dipper’’ in used as for the first one, but a much shorter exposure (about 30 seconds — but shorter exposures are needed - for stars further from Polaris) was used in order to ob- . tain point:star images, In the photo, the Big Dipper is oriented about as you -would see it on a clear May night — high overhead and upside down. In a previous’ column I’ve explained how the . ‘pointer’? stars at the énd of the cup can be used to find Polaris. The handle is also useful for finding stars, You'll notice that the handle is curved into-an arc. If you follow that arc you will come to the star Arcturus, the fourth brightest star in the night sky. Then continue on along this line and you will find another bright star, . Spica, in the constellation Virgo. Spica is almost exactly on the ecliptic, and of course, Virgo is a zodiac con- stellation. You might find the saying ‘‘follow the arc to _ Arcturus and then keep going until you spy Spica”’ (pro- nounced spy-ka) helpful to remember all this. The long twilight that we experience at our northern latitude at this time of ‘the year will make it difficult to see most planets this month. The main exception is Saturn which will rise in the east at about sunset and set in the southwest about sunrise. You may be able to see ‘Mercury near the western horizon late in the month — ‘on May 29 it should be 3° south of the waxing crescent moon: Mars will be in that area of the sky at the same time, To find it look to the east of Mercury. | I hope that you have enjoyed the photos that Corinna ‘and Heather took as much as I have. As the nights get warmer you might want -to try taking some similar photos yourself. Best wishes for another month. (Offs i in Grand Forks, B. C. - municipal building. Jackman as he put for- this photo. To take this photo the same equipment was for an estimated addi- _Fent out the ground floor ‘of city hall -after the . Ald, Doug Smith remark- Photo one shows star trails. -- My - "Terrace Review — Wednesday, May 6, 1987 17 Blg Dipper shown in the heavens. Speaker goes to provincials TERRACE — Darci Gilham of Terrace re- cently participated in the 4-H Provincial Speak by Philip Musselman - ' Although Gilham was a little disappointed Pavement at not winning, she has plans to try again. James Gilham, Darci’s: father, was very - proud of his daughter’s. enthusiasm, and the - _. fact that she is the first from Terrace to make . it as far_as provincial competition. . _ Each speech is five to seven minutes long 7 and ‘must be preceded by an impromtu. An im-: ‘promtu is an introductory test, which involves - a subject cliosen ‘by the judges: and each _ speaker has one minute in order to prepare. a two miriute talk on the topic. - | Gilham had performed ‘her speech three: times without cue cards and was prepared for the provincial event. Her. speech dealt with how adults could become better. parents. for. their teenagers. Gilham has been public speaking tor rour - years and plans to keep developing her talents. TERRACE — The paving work to begin soon on the & parking lot between city & hall-and the new RCMP building may be extended to cover the _ pothole- plagued area behind the “We'll never get it # cheaper,’ said Ald. Bob. § ward a motion to have the entire area done at once — tional cost to the city of about $30,000. The pro-" posal got a wary reception from other council mem- bers. Mayor Jack Talstra re- flected, ‘‘I can hear the public saying, “They can pave their own parking lot, but not our street. Talstra conceded, how- | ever, that a smoother sur- face in the lot would en- hance the city’s chances to RCMP move out. Ald. George Clark said ~ he would like to get a bet- ter overall picture of the upcoming budget, and ed, ‘‘There’s going to have to be strong justification for this, there are other & areas where that $30,000 | could be used,’’ Council tabled the mo- § tion to the next meeting of the Planning. and Public Works Committee, Maine _written and performed by: KENNETH BROWN directed by: MICHAEL PUTTONEN ADVANCE TICKETS: _. Adults: $41.00 -$SrJ Students: $7.00 _ $1,00 more at the door: 8:00 PM. oe ‘Monday 11th. May. 1987 Terrace’s R.E.M. Lee Theatre. ickets at Sight and Sound in the Skeena Mall |