August 2015 – Skies News

Focus Constellations: Cepheus, Cassiopeia, Camelopardalis, Ursa Major, Ursa Minor, Draco, Bootes, Hercules, Lyra, Aquila, Cygnus

Comet Journal

Comet C/2014 Q2 (Lovejoy) is currently at 9th magnitude will be between Draco, Bootes, and Hercules In August.

C/2013 US10 (Catalina) reached 8th magnitude in July and is on course to achieve naked eye status at the end of the year. It is currently deep in southern hemisphere skies and will not be visible for northern hemisphere observers until November and December.

Mars Landers

Opportunity is on the western rim of Endeavour Crater at Marathon Valley near Spirit of St. Louis Crater. The rover is operating on RAM memory as the Flash memory is still being bypassed due to the frequent amnesia events experienced over the last few months. Further investigation of the problem is being conducted in hopes of eventual correction.

From Sol 4072 (July 8, 2015) through Sol 4079 (July 15, 2015), the rover conducted contact science investigation of a Red Zone target along the edge of the Spirit of St. Louis crater. It first collected a Microscopic Imager (MI) mosaic, then placed the APXS on the target for a multi-hour integration. Opportunity then headed around the crater to the east with a 90-foot (27.5-meter) drive. Post-drive Navcam panoramas were collected from that new vantage point. On Sol 4078 (July 14, 2015), the rover departed and headed northeast towards Swan Hill with a 120-foot (36.7-meter) drive, collecting post-drive Navcam panoramas. On the next sol, Opportunity first collected some pre-drive targeted Navcam and Pancam images, then drove almost 62 feet (19 meters) heading into Marathon Valley. Following the drive, a 360-degree Navcam panorama was collected.

Opportunity has now traversed 26.38 miles (42.45 kilometers) over the Martian surface. Solar energy in the last month ranged from 450 to 500 watt hours per day.

In July, Curiosity continued its examination of the contact zone between the younger Washboard Unit which overlies the older Murray Formation, the basal formation at Mt. Sharp. The light colored mudstones of the Murray Formation underlie the finely bedded dark sandstones of the Stimson Unit (the basal part of the Washboard Unit) in Marias Pass.

A thin bed of coarser grained rock between the two formations contains larger grains of mixed shapes and colors, some of which are highly rounded and others quite angular. The mixture of textures and mineralogy of this unconformable boundary layer implies that the distant and surrounding landforms were subjected to an extensive period of erosion following deposition of the finer grained quiet water lake deposits of the Murray Formation. The coarser grains in the sandstones of the overlying Stimson Unit indicate more active erosion, transportation, and deposition processes followed the erosional activity.

A high silica area discovered at Elk during the climb to the contact led mission scientists to back up the rover for 46 feet so as to examine a similar target called Lamoose. These rocks are unlike any others found so far on Mars. Silicate minerals on Earth are composed of silicon, oxygen, and other elements. They make up Earths’ crust and mantle. Quartz is a silicate mineral composed of pure silicon and oxygen and is found primarily in the continental crust and its erosional products. Abundant silica poor basalt and absence of quartz in previously examined Martian rocks is more representative of basaltic ocean crust on Earth making the quartz rich rocks at Elk and Lamoose quite surprising

Meteor Showers.

The long awaited Perseid Meteor Shower culminates on the 12th and 13th under almost Moonless skies when a very thin waning crescent Moon rises just before dawn. Viewing conditions will be almost ideal for observers favored with light pollution free skies and clear weather. The radiant between Perseus and Cassiopeia from which the meteors appear to emanate is close to the zenith at the peak of the shower in the predawn hours. Observers viewing the radiant will peer into the shower center as Earth plunges headlong into a river of debris left in the wake of previous passages of Comet 109/P Swift-Tuttle. The Comet visits the inner Solar System every 130 years and last passed through in 1992. Sky and Telescope magazine reports that Earth will pass through a particularly dense part of the debris which was shed by the Comet in 1862. In 2013 the Perseids produced meteor counts of over 100 per hour in dark skies for a period spanning 12 hours at the peak and attained a level of over 40 per hour for a period of 72 hours.

The Perseids are among the most dependable and oldest showers as there are historical records of passages as far back as 36 AD in China and 811 AD in Europe.

Pluto: Here it comes! Here it comes! There it goes ––– here is what we found……

NASA’s New Horizons spacecraft made its closest approach 7750 miles from Pluto on Tuesday July 14th and flew by at 31,000 miles per hour. In the brief 2 day interval during which cameras collected some pretty interesting information about the dwarf planet, dark equatorial regions and a large white heart shaped area dotted by water ice mountains were photographed on Pluto’s surface. Methane ice caps were found near the poles and snow appears in other areas. The absence of craters in the areas first examined in high resolution indicates that the surface is young, probably less than 100 million years old. Charon, Pluto’s large Moon, displays gigantic chasms, cliffs, and troughs probably produced by surface fracturing due to internal processes.

The icy moons of the giant planets are heated by gravitational interactions with larger planetary bodies which don’t exist near Pluto and Charon so other processes must be generating the puzzling landscapes of each world, forcing scientists to rethink what powers the geological activity which produced these landforms.

Planet Plotting

Jupiter and Saturn are evening planets in August. Right after sunset at the beginning of the month Venus (-4.4) is on the western horizon below Regulus and Jupiter (-1.7) in Leo. All three set soon after the Sun and disappear from evening skies as August progresses. Jupiter reaches solar conjunction and is on the other side of the Sun on the 26th. Saturn is visible after sunset in Libra in the southwestern sky and sets after midnight. Uranus and Neptune rise before midnight and Mercury is hidden in the glare of the Sun throughout the month.

Mars (+1.7 to +1.8) moves from Gemini into Cancer in August and rises before dawn. Uranus (5.8) in Pisces, and Neptune (7.8) in Aquarius are dim morning planets in the southwestern sky.

Venus (-4.4 to -4.7) reaches inferior conjunction with the Sun on the 15th and reappears in the eastern predawn sky in Cancer during the last week of August. Venus and Mars will be 9° apart on the 29th.

Saturn in Libra decreases slightly in brightness in August from magnitude +0.4 to +0.5 as Earth orbits away from the ringed planet. Saturn appears to dim and grow smaller but the tilted wide open rings remain a magnificent sight in the southern sky after sunset.

Planet……Constellation……Magnitude……Planet Passages

Sun………Leo………..-26.8………………….New Moon, ………………………………………………………..8/14, 10:53AM EDT Mercury…Leo………-1.2 to +1.0………….Jupiter, 0.6°S, ………………………………………………………..8/6, Midnight EDT Venus……Leo…….-4.4 to -4.1 to -4.5….Inferior Conjunction ………………………………………………………..8/15, 3:00PM EDT ……………………………………………………….Mars, 9.0°N, ………………………………………………………..8/29, 1:00AM EDT Mars…Gemini, Cancer…+1.7 to +1.8…….Venus, 9.0°S, ………………………………………………………..8/29, 1:00AM EDT Jupiter…..Leo…………………-1.7…………….Mercury, 0.6°N, ………………………………………………………..8/6, Midnight EDT ………………………………………………………..Solar Conjunction ………………………………………………………..8/26, 6:00PM EDT Saturn…..Libra………….+0.4 to +0.5 Uranus….Pisces……………..+5.8
Neptune..Aquarius…………+7.8

August Moon

Lunation 1146 begins with the New Moon of August 14th at 10:53AM EDT. It ends 29.54 days later with the New Moon of September 13th at 2:41AM EDT.

The Full Moon for August is in Capricornus at 2:35 PM EDT on the 29th. This Full Moon is called the “Grain or Green Corn Moon”. The Full Moon is the 9th Moon of the year and is designated by the Anishinaabe (Odawa and Ojibwe) of the northern Great Lakes as “Waatebagaa-giizis” (Leaves Turning Moon). Celts called the August Full Moon the “Dispute Moon” and Medieval English referred to it as the “Corn Moon.” It is the “Harvest Moon” for the Chinese. Colonial Americans called it the “Dog Days Moon”. The “Dog Days” are named after Sirius, the “Dog Star” which rose with the Sun (heliacal rising of Sirius) in 3000 BC, preceding the flooding of the Nile which occurred around June 25th, near the summer solstice, marking the Egyptian New Year. Today it occurs within a few weeks of August 15th, owing to precession of Earths’ Axis.

The Moon is nearest (perigee) in its orbit (225,023 miles or 56.78 Earth radii) on August 2nd at 6:03AM EDT and again (222,631 miles or 56.18 Earth radii) on the 30th at 11:21AM EDT. Apogee distance (maximum distance) is 252,182 miles (63.63 Earth radii) from Earth on the 17th at 10:33PM EDT.

Planet..Constellation..Magnitude..Moon Passage..Moon ………………………………………………………………….Phase/Age

Sun………..Leo……..-26.8………9:24PM EDT, 7/15 ………………………………………………………………New ~ 0 days Mercury…..Leo………-0.2…………..2.0°S, 11AM EDT, 8/16 …………………………………………Waxing Crescent ~ 2.03 days Venus……..Leo……….-4.1…………4.5°NNE, 2PM EDT, 8/14 …………………………………………Waxing Crescent ~ 0.69 days Mars…….Gemini…….+1.7…………6.0°S, 1AM EDT, 8/13 …………………………………………Waning Crescent ~ 28.15 days Jupiter….Leo………….-1.7………….3.5°SSW, 6AM EDT, 8/15 …………………………………………Waxing Crescent ~ 1.44 days Saturn….Libra………..+0.5………….3.0°N, 1PM EDT, 8/22 …………………………………………Waxing Crescent ~ 8.11 days Uranus….Pisces……..+5.8………….1.0°S, 5AM EDT, 8/5 …………………………………………Waning Gibbous ~ 20.32 days Neptune..Aquarius….+7.8…………3.0°N, 11AM EDT, 8/2 …………………………………………Waning Gibbous ~ 17.57 days
Neptune..Aquarius….+7.8…………3.0°N, 8PM EDT, 8/29 …………………………………………Waning Gibbous ~ 16.40 days