Constellations:Apus, Ara, Boötes, Carina, Centaurus, Chamaeleon, Corvus, Crux, Hydrus, Leo, Musca, Norma, Octans, Orion, Scorpius, Ursa Major Asterisms: "False Comet" in Scorpius, Teapot, Winter Circle Galaxies: Large Magellanic Cloud (LMC), Small Magellanic Cloud (SMC) Nebula: Coalsack Nebula, NGC 3324 / Keyhole Nebula, Tarantula Nebula/NGC 2070 Clusters: β Crux, Collinder 361 (in Sagittarius), Herschel's Jewel Box/NGC 4755, NGC 6231 (in Scorpius), NGC 6397, Omega Centauri, Southern Pleaides/IC 2601, 47 Tucanae/NGC 104, Trumpler 24 Planet: Jupiter (in Libra), Saturn and Mars in Sagittarius, Venus Stars: Achernar, α Centauri, β Centauri, HD111122, double star δ1 Apodis and δ2 Apodis (in Apus) Messier Object: M8 (Lagoon Nebula)
Location: San Pedro de Atacama, Chile Date: 2018-04-15/16 Time: 8:00 PM - 1:00 AM EST Instrument: Visual + Binoculars 10x42 IS + 450 mm F5 Dobsonian with 21 mm Ethos eyepiece Transparency: Very Good (4) Seeing: Very Good (4) Temperature: 10º C - 5º C
No wind initially but a light breeze later in the evening. No cloud. No flies.
Charline, Melody, Judy Jerry beside an ALMA scope
Melody, Judy, Jerry and Charline rose early to arrive in time for the tour bus to the Atacama Large Millimeter/submillimeter Array (ALMA). Due to its dryness, high altitude, scant clouds and scarce radio interference and light pollution from cities, this location was deemed one of the best places on Earth for astronomic observation. The bus turned to go up the mountain range towards the Chajnantor Plateau where the Array Operation Site (AOS) itself was constructed at elevation 16,000 ft / 5,000 m ASL. However, the tour was only going to the Operation Support Facility (OSF) at the lower elevation of 9,515 feet / 2,900 m ASL to reduce altitude sickness risks for staff, volunteers and visitors alike.
One of the 66 AOS dishes was at OSF for repairs, and the two 28-wheel dish transporters were there as well. Talk about luck! It showed us how large these scopes and their transporters to the Array truly are.
ALMA 28-wheel transporter
Back at the Lodge after supper, five of us gathered in the adjacent yard of the ladies' lodge - Melody, Charline, Dave, Jerry and me. I discovered that Leo had a backwards upside-down sickle. In looking closer at Eta Carina, I discovered the keyhole Nebula (NGC 3324). Dave pointed out the “false comet” seen in the tail of Scorpius. In observing it, I was able to identify NGC 6231, Trumpler 24 and Collinder 361. He also showed us the Tarantula Nebula in a 450 mm F5 Dob with 21 mm Ethos eyepiece, then he used OIII (oxygen 3) and UHC (Ultra-high Contrast) to demonstrate the variations in viewing. Fascinating!
Carina Time: not recorded S&T Chart Reference: 28, 30, 39, 40 Instrument: Visual Was again able to find Canopus, β, ε and θ.
Coalsack Nebula Time: not recorded S&T Chart Reference: 49, 50 Instrument: Visual Very easy to find below Crux. It appeared visually as a very dark patch in the Milky Way. Using the binoculars, you could see a few stars peeking through.
Hershel's Jewel Box / NGC 4755 Time: not recorded S&T Chart Reference: 38 Instrument: Visual The Jewel Box could readily be found naked eye. Such a wonderful DSO.
Centaurus Time: not recorded S&T Chart Reference: 48, 49, 59 Instrument: Visual I verified I could visually find the stars Rigel, Hader, Birdun, Muhlifain, α Centauri, π Centauri and τ Centauri around Crux. The stars α Centauri and β Centauri were especially bright stars adjacent to the Milky Way.
Omega Centauri Time: 8:30 PM EST S&T Chart Reference: 48, 49, 59 Instrument: Telescope Dave was using the Lodge's telescope this evening and showed us the very tight and bright cluster. Viewed it again at 9:19 PM.
Ursa Major Time: not recorded S&T Chart Reference: 31, 32, 33, 43, F Instrument: Visual Ursa Major was once more pouring out its contents with Mizar-Alcor only about 2º above the horizon. Quite a mind bender! Dubhe was again hidden by the tree adjacent to the Lodge.
Venus Time: 8:11 PM EDT Instrument: Visual Venus could be easily seen in the western sky coming up through Aries between Cetus and Perseus just on the horizon and below Taurus.
Achernar (in Eridanus) Time: 8:16 PM EST S&T Chart Reference: 6, 126, 17, 19 Instrument: Visual Achernar was again only 5º - 7º above the horizon and was very easily found.
Hydrus Time: 8:16 PM EST S&T Chart Reference: 10, 20 Instrument: Visual Could easily make out the Small Magellanic Cloud (SMC) and the triangular formation of Hydrus visually.
Orion Time: 8:21 PM EDT S&T Chart Reference: 14, 16, B Instrument: Visual Orion was once more reclining on his side, his sword pointing upwards.
Orion, Lepus, Canis Major, Canis Major M44 (Beehive Cluster) in upper right - Photo by Jerry Black
Leo Time: 8:25 PM EST S&T Chart Reference: 34, 35, G Instrument: Visual Nothing like seeing this with a totally different orientation! What initially alerted me to Leo was the seemingly backwards and upside-down sickle. Using SkySafariPro, I confirmed it was Leo and looked for Denebola. This star was lower than I expected.
47 Tucanae Time: 8:30 PM EST S&T Chart Reference: 10, 80 Instrument: Visual + Telescope I never did find the stars in the constellation Tucana. However, Dave was using 450 mm F5 Dobsonian with a 21 mm Ethos eyepiece. The globular cluster 47 Tucanae has an apparent magnitude of 4.1. Very dense core with less dense edges. It's the second brightest globular cluster after Omega Centauri. It looked like a star when located naked eye; didn't use binoculars to view it.
Tarantula Nebula / 30 Doradus / NGC 2070 Time: 8:40 PM EST S&T Chart Reference: 20, 30 Instrument: Visual + Telescope This is an emission nebula with an apparent magnitude of 8.0. It is located at the eastern end of the stellar bar of the Large Magellanic Cloud (LMC).
Two clusters are in the Nebula:
R136 containing several extremely large stars
Hodge 301 Contains 3 red super-giants
We first viewed the Tantula just using the eyepiece provided by the Lodge. Melody then provided 2 filters for comparison
OIII (Oxygen 3) filter: it reduced the light and sharpened the features of the nebula.
UHC (Ultra High Contrast): it also reduced the light.
Winter Circle - North vs. South Hemispheres Time: 8:40 PM EST Instrument: Visual I noticed the stars of the Winter Circle were all visible in San Pedro but that they had a slightly different orientation in relation to where they were relative to the Zenith. I drew the Circle as it appeared at this time. Later in the evening in my Lodge, I used SkySafariPro to determine the 'look' of the Winter Circle back home. Here are the comparisons.
Crux + HD111122 Time: 9:23 PM EST S&T Chart Reference: 38, 49, 50 Instrument: Visual + Binoculars Located Crux near the Coalsack Nebula then found the 8th magnitude HD111122. It was a red carbon giant located at 9 o'clock to Becruz (β Crux).
Musca ("the Fly") Time: 9:37 PM EST S&T Chart Reference: 50 Instrument: Visual I observed the 6 main stars of Musca visually. None were extremely bright so had to concentrate my gaze to see them.
Apus (Bird of Paradise) Time: 9:54 PM EST S&T Chart Reference: 40, 50, 60, 70 Instrument: Visual Visually located APus by triangulating (sort of) with Circinus and Musca. Found the flowerhead formed by δ, β and γ then located α higher in the sky.
I used my binoculars to view the flower head and discovered the double star δ Apodis (δ1 and δ2). They were parallel to the horizon at this time and δ1 was the larger of the two.
Octans (Octant) Time: 9:58 PM EST S&T Chart Reference: 10, 60, 70, 80 Instrument: Visual This constellation is circumpolar and represents a reflecting octant - a navigational instrument used in astronomy with a 45º arc to measure latitude and longitude.
I was looking in the general area of Hydrus for other constellations. The triangle of the constellation was found but truly had to concentrate in the area of the sky. I used Roy's star map of the southern sky for orientation.
Jupiter (in Libra) Time: 10:04 PM EST Instrument: Visual
Very easy to see Jupiter in Libra. It lay on the line (finally!) between α and γ Librae. Very bright and easy to see at 18º above the horizon.
Southern Pleaides / IC 2602 / θ Carinae Cluster Time: 10:05 PM EST S&T Chart Reference: 38, 40 Instrument: Binoculars The hour glass shape of stars was easily seen beside the row of stars on the right. Very distinctive arrangement of stars.
Boötes Time: 10:23 PM EST S&T Chart Reference: 42, 44, 53, 55 Instrument: Visual At 10:23 PM, I noticed Arcturus in the sky. However, all of Boötes didn't rise above the horizon until 11:20 PM.
Chamaeleon Time: 10:47 PM EST S&T Chart Reference: 30, 40, 50, 60 Instrument: Visual This is a very small constellation that took some time to locate. Australians sometimes refer to it as the "frying pan". alpa and theta form a wide double star.
NGC 3195 (a planetary nebula) is located near delta but can only be seen by telescope (which I didn't use at this time). Its central star has a magnitude of 15.3.
"False Comet" in Scorpius Time: 11:05 PM + 12:39 AM EST S&T Chart Reference: 56, 58, J Instrument: Visual + Binoculars By 11:05 PM, all the stars of Scorpius were well above the horizon. Shaula and Lesath were about 2º above the horizon. Dave Chapman pointed out the "false comet" asterism at the top of the curve of the tail. It truly did look like a comet with a series of stars following it.
Using my binoculars at 12:39 AM from the back patio of our Lodge, it looked like a group of 2 star clusters: - NGC 6231 formed the head of the "comet" - Open cluster Trumpler 24 and Collinder 362 formed the tail
Ara (the "Altar") Time: 11:10 PM + 11:25 PM EST S&T Chart Reference: 58, 60, 69 Instrument: Visual + Binoculars Ara is the 63rd largest constellation near the "Bend in Scorpius' tail. The name is associated with the altar on which the gods swore allegiance to Zeus before going into battle with the Titans.
11:10 PM: Used naked eye to locate the constellation and its major stars. Didn't use binoculars to view any of them.
Stars in Ara: - β Arae: Brightest star, orange supergiant with apparent mag 2.85 - α Arae: 2nd brightest star. Blue-white main sequence star. Fast rotation results in a dense cloud of equatorial emissions. Varying mag 2.76-2.90 - ζ Arae: 3rd brightest star, orange giant with mag 2.11 - δ Arae: Blue-white main sequence star at mag 3.6 - ε Arae: orange giant at apparent mag 4.1 - η Arae: orange giant of apparent mag 3.76
11:25 PM: Looking through binoculars, I found β Arae where I discovered 3 stars heading down towards a globular cluster. Turns out it was NGC 6397 with mag 5.73. Not as compact as Omega Centauri but still very easily seen with a dense core. A pleasant surprise! Had to share this Melody and Charline.
Norma (Carpenter's Square) Time: 11:13 PM EST S&T Chart Reference: 58, 59 Instrument: Visual + Binoculars Easier to find using the "False Comet" in Scorpius as the start point for star hopping. Four of Norma's brighter stars (γ, δ, ε and η) make up the square.
Stars in Norma: - γ1 & γ2 Normae: Optical double with mag 10. γ2 Normae is a yellow giant and γ1 Normae is a yellow-white supergiant. - ε Normae: A spectrographic binary with two blue-white main sequence stars at mag 7.5 - η Normae: yellow giant of apparent mag 4.65 - δ Normae: Blue-white mag 4.73. Displays the spectrum of a metal-lined A-type chemically peculiar star.
The Teapot rose out of the southern skies almost straight up with the spout first. An unusual orientation from what we normally see in the Northern Hemisphere. Mars and Saturn rose with the Teapot and I discovered a northern friend
Saturn (near the Teapot) Time: 12:17 AM EST Instrument: Visual + Binoculars Saturn was visible naked eye and with binoculars. The 4 stars in the Teapot handle were still below our mountainous horizon. Saturn rose on the side of the Teapot near Kaus Borealis with M22 between them.
Mars (near the Teapot) Time: 12:32 AM - 12:43 AM EST Instrument: Visual + Binoculars The handle of the Teapot had now cleared the mountains and was above the horizon. Both Saturn and Mars were now visible on the lid-handle side of the asterism.
Mars was approximately 2º above the horizon near Nunki and appeared yellow-orange in colour.
M8 (Lagoon Nebula) Time: 12:35 AM EST Instrument: Binoculars I was searching the stars around the Teapot and this jumped out at me. I was not expecting to see M8. It was so exciting to find a familiar DSO!
