Successful Observing Sessions HOWL-EEN FUN Kepler’S Supernova Remnant Harvard’S Plate Project and Women Computers
Total Page:16
File Type:pdf, Size:1020Kb
Published by the Astronomical League Vol. 69, No. 4 September 2017 Successful Observing Sessions HOWL-EEN FUN Kepler’s Supernova Remnant Harvard’s Plate Project and Women Computers T HE ASTRONOMICAL LEAGUE 1 he 1,396th entry in John the way to HR 8281, is the Dreyer’s Index Catalogue of Elephant’s Trunk Nebula. The T Nebulae and Clusters of left (east) edge of the trunk Stars is associated with a DEEP-SKY OBJECTS contains bright, hot, young galactic star cluster contained stars, emission nebulae, within a large region of faint reflection nebulae, and dark nebulosity, and a smaller region THE ELEPHANT’S TRUNK NEBULA nebulae worth exploring with an within it called the Elephant’s 8-inch or larger telescope. Trunk Nebula. In general, this By Dr. James R. Dire, Kauai Educational Association for Science & Astronomy Other features that are an entire region is absolute must to referred to by the check out in IC pachyderm 1396 are the proboscis phrase. many dark IC 1396 resides nebulae. Probably in the constellation the best is Cepheus and is Barnard 161. This located 2,400 light- dark nebula is years from Earth. located 15 To find IC 1396, arcminutes north start at Alpha of SAO 33652. Cephei, a.k.a. The nebula Alderamin, and go measures 5 by 2.5 five degrees arcminutes in southeast to the size. The nebula is fourth-magnitude very dark. Myriad red star Mu Cephei. Milky Way stars Mu Cephei goes by surround the the Arabic name nebula, but none Erakis. It is also can be seen in called Herschel’s this small patch of Garnet Star, after the sky. Sir William Another notable Herschel, who dark nebula is noted it was one of Barnard 163, the deepest-red-colored stars in eyepiece. Larger reflectors, like left of HR 8281 in the image. located one degree south- the sky. It is very hard to my 14-inch Dob, can reveal the This star, known as SAO 33652, southeast of HR 8281. Barnard mistake Erakis in the eyepiece! faint glow of the nebular gases, is a binary star with compo- 163 is slightly larger than The center of IC 1396 is 1.5 but the field of view captures nents magnitude 7.4 and 8.6 Barnard 161. Its cold gas and degrees south of Erakis. only a small fraction of the located 12.7 arcseconds apart. dust does an equally good job of My image of IC 1396 was entire nebula. The final multiple star system blocking light from stars behind taken with a William Optics Star A magnitude 5.7 star, HR I will point out in the image, it! The third dark nebula I want 71 mm f/4.9 apochromatic 8281, lies at the center of IC easily resolved in most tele- to point out in IC 1396 is refractor using an SBIG STF- 1396. HR 8281 is a triple star scopes, is located at the 10 Barnard 367, which lies 50 8300C CCD camera. The that is easily resolved. The o’clock position from HR 8281, arcminutes east-southeast of exposure was 220 minutes. The primary star, HR 8281 A, about two-thirds of the way HR 8281. Spanning 5 arcmin- image spans three degrees left to provides most of the light from HR 8281 to the edge of the utes, Barnard 367 is not quite right (east to west), capturing emitted by the system. The image. The star, SAO 33737, is as dark as the other two dark most of the nebula. I just missed secondary (B) and tertiary (C) just at the top edge of a small, nebulae. However, it is still an capturing Herschel’s Garnet Star components are both magnitude propeller-shaped dark region. impressive sight in a telescope. in the field of view. It would be 7.5 and lie 11 and 20 This triple star has components Panning around this large located just above the top (north) arcseconds away from A. HR of magnitude 9.6, 10.2, and Milky Way object with any of this image field about 20 8281 A has two other compo- 12.9. The magnitude 12.9 star telescope reveals the hundreds percent of the way from left to nents located 1.8 and 0.1 is 6.9 arcseconds from the of stars formed within it, myriad right, located in the outer region arcseconds from it that are too primary while the magnitude double star systems, and an of this vast emission nebula. faint to be seen in amateur 10.2 star is 19.8 arcseconds uncountable number of more It’s virtually impossible to see telescopes. from the primary. distant suns. The glow of the this entire nebula at once in a Another great star to check On the right edge of the nebula appears as a faint telescope. Smaller scopes that out in IC 1396 is the magnitude nebula is a magnitude 7.4 star background between the stars provide a wide enough field of 7.4 star located 13 arcminutes known as V429 Cephei. The dark that is not as dark as the inter- view lack the light gathering northeast of HR 8281. It’s the lane in the image to the left of stellar space outside of this power to see the nebula in an next brightest star to the upper V429, extending three-fourths of region. 8 T HE ASTRONOMICAL LEAGUE 9.