Archive for year: 2016

12/7/2016
December Skies – by Dick Cookman

Highlights: Comet Journal, Martian Landers, Meteor Showers, December Solstice, Planet Plotting, December Moon

Focus Constellations: Camelopardalis, Auriga, Gemini, Orion, Taurus, Perseus, Cassiopeia, Andromeda, Pegasus, Cepheus, Draco, Ursa Minor, Ursa Major, Lynx

Comet Journal

Comet 45P/Honda-Mrkos-Pajdusakova has a short period, 5.25 year, orbit and may achieve 10th magnitude when briefly visible in Sagittarius during early December. It will be too close to the Sun to see in late December and will appear in the morning sky in early 2017 after passing through perihelion on Dec. 31st. It is expected to stay at about 7th magnitude as it circuits through northern predawn skies from January and February.

C/2016 U1 (NEOWISE) is another subvisual comet best seen in January when it passes through perihelion on the 14th. It moves from the end of the tail of Ursa Major to Ophiuchus in December and may increase from 12th to 8th magnitude.
2P Enke, V2 Johnson, and 41P/Tuttle-Giacobini-Kresak are potential naked eye candidates on the doorstep for 2017.

Mars Landers

From Sol 4521 (Oct. 11, 2016) through Sol 4534 (Oct. 26, 2016) Opportunity was at Spirit Mound on the rim of Endeavor Crater, the first science waypoint of the 10th extended mission.

The rover prepared for observation of the Schiaparelli EDM entry, descent and landing, and imaged the expected landing area on Sol 4528 (Oct. 19, 2016). No evidence of the lander was found even though Schiaparelli performed all entry functions, measurements, and communications without flaw. During descent a one second malfunction of the Inertial Measurement Unit (IMU) resulted in an altitude determination error and a premature parachute release. The resulting crash evidently destroyed the lander. Opportunity relinquished relay support to EDM until the 26th when science activities at Spirit Mound were resumed.

On Sol 4546 (Nov. 6, 2016), the rover drove about 112 feet (34 meters) to the south-southwest, heading for the next waypoint, the “gully”. After traveling east about 39 feet (12 meters) on Sol 4550 (Nov. 10, 2016) the mission was interrupted on Sol 4552 (Nov. 12, 2016) by excessive wheel current due to a sharp turn on a steep slope, so the rover continued for another 39 feet to gentler slopes. Steep slopes and scattered boulders necessitated imaging following the drive on Sol 4559 (Nov.19, 2016) to find a route forward and the Sol 4566 (Nov. 27, 2016) drive of 56 feet (17 meters) was followed by an additional 82 feet (25 meters) on Sol 4568 (Nov. 29, 2016). Solar array energy production is 465 watt-hours and total odometry is 27.05 miles (43.52 kilometers).

After drilling into and sampling the lacustrine (lakebed) sedimentary rock of the Murray Formation at Quela on the flank of Mt. Sharp on Sol 1465, Curiosity continued uphill, arriving at the next drilling target, Sebina, on Sol 1491, October 14, 2016. Further tests were performed on the Quela tailings and on the Sebina rock outcrop before proceeding with the drilling program on Sol 1495 after which the upward journey resumed on Sol 1500, October 24, 2016. After completing 1500 kilometers of total travel on Mars on Sol 1528, Curiosity reached the next drilling site in the Murray Formation called Precipice on November 21, 2016. The science laboratory also conducted numerous atmospheric observations along with detailed outcrop and panoramic imaging of the rocks and landforms along the route. Drilling of Precipice in currently on a delay due to drill malfunction which is currently being evaluated.

Meteor Showers

The Geminid Meteor Shower peaks on the 13th, the night of the Full Moon. The source of the shower was unknown until 1983 when Fred Whipple noticed that an object later named 3200 Phaeton had an almost identical 1.5 year orbit. It will again pass through our orbit in 2017 and may be an asteroid or an ancient bare comet, denuded of its volatiles.

Since the meteors emanate from Gemini and the Moon is in nearby Taurus, meteors hidden in its glare will not appear unless they streak well away from the Moon. In years when the Moon or clouds don’t interfere, the Geminids have supplanted the August Perseids as the most dependable meteor shower, typically exhibiting 50 to 130 meteors per hour in skies free of light pollution.

Observers may have a better view of the Ursid Meteor Shower on the 22nd. The shower normally produces a few fireballs and 10 to 50 meteors per hour in dark skies, meteors which will not have to contend with a Full Moon. The comet which produced the debris causing the Ursids is Comet 8P Tuttle which has a 13.5 year orbit and last visited in January, 2008.

December Solstice

On the Winter Solstice at 5:44AM EST on the 21st, the axis of the Earth achieves its maximum tilt away from the Sun which will rise at its southernmost spot on the eastern horizon. For observers in the northern United States at 45° N, the bearing of the rising Sun will be 124° or 34° south of east. For those in the southern United States at 30° N, the bearing will be 117° or 27° south of east. The Sun’s altitude above south at solar noon will be 21.5° and 36.5° respectively, the lowest of the year. Sunset bearings will be 236° (34° south of west) and 243° (27° south of west) for northern and southern observers.

At latitude 40°N, the latest sunrise of the year is on January 5th. The earliest sunset occurs on December 7th. The dates of each get closer to the solstice as latitude increases. Even though the solstice is the shortest day of the year, neither of the above coincides with the solstice because we measure the times of sunrises and sunsets by mean solar time (clock time), not local solar time (sundial time).

The tilt of Earth’s axis does not change through the year but its angle from the Sun changes as Earth revolves around its orbit. The northern hemisphere is cooled when it tilts away from the Sun in the winter and is warmed when tilting toward the Sun in the Summer. In addition to this annual change in tilt relative to the Sun, the axis tilt of 23.5° cycles from 21° to 24.5° with a very long period of 40,000 years. At low tilt, summers are cooler and winters warmer. At higher tilt, the reverse occurs.

Planet Plotting

Mercury (-0.5 to -0.3) in Sagittarius reaches Maximum Elongation of the 10th when it is 21° from the Sun and 7° above the southwestern horizon 30 minutes after sunset. Venus (-4.1 to -4.4) is very bright in the southwestern sky and provides its best apparition of the year as it rises from 15° to 25° above the horizon an hour after sunset during December. It moves from Sagittarius to Capricornus during the month. Mars (+0.5 to +0.9) in Capricornus and Aquarius is higher than Venus in the southwestern sky after sunset and Venus will close the distance from the red planet as Mars moves toward Neptune (+7.9) in Aquarius during December. By the New Year, Mars and Neptune will appear closer to one another than at any other time during the last 700+ years. Uranus (+5.8) in Pisces is in the southern sky after sunset and sets after midnight.

Jupiter (-1.8 to -1.9) rises in Virgo as Uranus sets in the west. It ascends to about 30° above the southeastern horizon by an hour before morning twilight and dominates the predawn sky. Saturn (+0.5) in Ophiuchus is in conjunction with the Sun on the 10th and is lost in its glare until late in the month when it makes its appearance in the morning sky. By the 31st, it rises in the southeast about 45 minutes before the Sun.

Planet Constellation Magnitude Planet Passages

Sun..Ophiuchus, Sagittarius..-26.8………….New Moon, 11/29, …………………………………………………………………7:18AM EST Mercury…Sagittarius…….-0.5 to -0.3……..Max. E. Elong. ……………………………………………………….12/10, Midnight EST ………………………………………………..Inferior Solar Conjunction ……………………………………………………….12/28, 2PM EST
Venus..Sagittarius, Capricornus..-4.1 to 4.4
Mars…..Capricornus, Aquarius..+0.5 to +0.9..Neptune, 0.1°N. ……………………………………………………….12/31, 9PM EST Jupiter ………Virgo…………………..-1.8 to -1.9 Saturn…….Ophiuchus……..+0.5……………..Solar Conjunction, ………………………………………………………..12/10, 7AM EST
Uranus…….Pisces…………..+5.8
Neptune…..Aquarius……….+7.9

December Moon

The New Moon of December is on the 29th at 1:53AM EST. The New Moon is the beginning of Lunation 1163 which ends 29.72 days later with the New Moon of January 27th at 7:07PM EST.

The Full Moon in December in Taurus occurs at 7:06PM EST on the 13th. It is just below the horns of the Bull and was above the Bull in November. Ignoring the issue of gender, the cow has jumped over the Moon, just like Mother Goose told us.

The December Moon is called the “Moon before Yule”. Colonial Americans used the term “Christmas Moon”. The Celts called it the “Cold Moon”, and the Chinese agree when they refer to it as the “Bitter Moon”. Medieval English thought of it as the “Oak Moon”, and the Anishinaabe (Odawa and Ojibwe) people of northern Michigan recognize it as “Manidoo-gizisoons” (Little Spirit Moon).

Lunar perigee distance (closest to Earth) is 222,737 miles or 56.21 Earth radii on the 12th at 6:29PM EST. Full Moon occurs 24+ hours later, producing a large “Supermoon” which is slightly smaller than that of November. The Moon is at the apogee position in orbit (maximum orbital distance) at 252,196 miles (63.63 Earth radii) from Earth on the 25th at 12:55AM EST.

Cecil Adams’ reasons why we need the Moon:
“Reason #2: It keeps us toasty. The impact of a planetary object about the size of Mars with the primordial Earth also contributed to the heating of earth’s iron core, which provides us with our relatively strong magnetic field. This in turn protects us from (cancer causing) radiation……and solar winds. And the pull of the moon’s gravity acts on every molecule on earth, powering the tides……and creating additional heat, which helps keep the core from cooling too quickly”.

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

Sun……….Sagittarius……..-26.8…………7:18AM EST, 12/29 ……………………………………………………………New ~ 0 days Mercury…Sagittarius……..-0.3……1.8°N, Midnight EST, 12/29 ……………………………………………………..Waning Crescent ~ ………………………………………………………………..29.7 days Venus……Sagittarius……….-4.1………..6.0°N, 8AM EST, 12/3 ……………………………………………………..Waxing Crescent ~ …………………………………………………………………4.03 days Mars……..Capricornus………+0.5……….3.0°N, 6AM EST, 12/5 ………………………………………………………Waxing Crescent ~ ………………………………………………………………..5.95 days Jupiter……..Virgo…………….-1.9………2.0°N, Noon EST, 12/22 ……………………………………………………..Waning Crescent ~ …………………………………………………………………23.20 days Saturn…….Ophiuchus………+0.5………4.0°N, 4PM EDT, 12/27 …………………………………………………….Waning Crescent ~ ………………………………………………………………28.36 days Uranus…….Pisces……………+5.8……….3.0°S, 3PM EST, 12/9 …………………………………………………….Waxing Gibbous ~ ……………………………………………………………….10.32 days Neptune……Aquarius……….+7.9………0.7°N, 5PM EST, 12/6 …………………………………………………….Waxing Crescent ~ ……………………………………………………………….7.40 days 

10/10/2016
October Skies by Dick Cookman

Highlights: Comet Journal, Martian Landers, Meteor Showers, Halloween, Planet Plotting, October Moon

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

Comet Journal

October is not a good month for bright or even moderately bright comets. Nothing is expected to exceed 11th magnitude necessitating giant binoculars or telescopes for comet observation. There are 4 Christmas, winter and Easter comets which may achieve naked eye visibility. They include Comet 45P/Honda-Mrkos-Pajdusakova, Comet 2P Enke (see Taurid meteor shower below), Comet V2 Johnson, and Comet 41P/Tuttle-Giacobini-Kresak.

Mars Landers

Opportunity departed from the northern margin of Marathon Valley on the rim of Endeavour Crater on Sol 4453 (August 2, 2016) and headed south across the valley. The rover reached the southern side of the valley on Sol 4480 (August 30, 2016). After receiving its 10th mission extension on Sept. 1st, the rover entered a small valley (Lewis & Clark Gap) cutting through Wharton Ridge on the southern side of Marathon Valley. Opportunity then descended the ridge into Bitterroot Valley which trends northeastward and drops into the depths of Endeavour Crater. By Sol 4500 (Sept. 20, 2016) the rover reached Spirit Mound at the eastern terminus of Bitterroot Valley. After examining the rocks at a nearby surface feature (Gasconade), scientists plan to make detailed observations of the material making up the mound, then move the rover onto the vast floor of the 14 mile wide crater and compare the rocks of the floor to the sulfate-rich rock of the plains surrounding the crater.

From Sol 4473 (Aug. 23, 2016) through Sol 4514 (Oct. 4, 2016) Opportunity traveled 0.21 miles (0.34 kilometers) achieving a total distance on Mars of 26.99 miles (43.44 kilometers). Solar array energy production ranged from 453 to 582 watt-hours per day.

On Sol 1422 (August 5, 2016), after almost 4 years of travel on Mars, Curiosity arrived at the Murray Buttes region of lower Mt. Sharp, the Mt. Rainier size peak in the center of 96 mile wide Gale Crater. The buttes are an area of isolated exposures of younger sandstone resting above the lower 300 foot thick lake bottom mudstone of the 600 foot thick Murray Formation. Sandstone buttes and mesas are capped with a relatively cohesive rock layer which protects them from erosion. The scenic landscape is very reminiscent of spectacular areas in the American southwest. The sand making up the sandstone accumulated as sand dunes built on the underlying material of the Murray Formation. The sand dunes were later lithified into rock as minerals deposited by groundwater percolating through the sand cemented the sand grains together. Later erosion removed most of the lithified dune layer leaving the isolated remnants.

Since the area appeared to be a likely candidate for the 14th drill site, a location near the base of one of the buttes was chosen for drilling. After an aborted drilling attempt at Quela on Sol 1461 (Sept. 15, 2016), the drilling problem was assessed and a second attempt on Sol 1466 (Sept. 19, 2016) recovered an appropriate sample of drilling powder. Curiosity resumed its uphill trek away from Murray Buttes and toward the younger rock above the Murray Formation. Detailed measurements made of the sandstone of the Murray Formation at the Kopong outcrop on Sol 1473 (Sept. 27, 2013) revealed details in the cross-bedded layering, rock texture, and abundant light colored mineral veins lacing through the rock layers which were formed as calcite crystals were precipitated from ground water percolating through the fractured bedrock.

Analysis of gases measured by the regular atmospheric sampling conducted by Curiosity reveals that the ratios of isotopes of xenon and krypton indicate unexpected abundances of certain isotopes. This can be explained by cosmic ray bombardment of barium and bromine on the Martian surface altering them to xenon and krypton which then escaped to the atmosphere.

As part of the two year mission extension commencing on Oct. 1st, the next year will be devoted to examination of the upper part of the Murray Formation and the following year will concentrate on the overlying Hematite Unit (a ridge which is 1.5 miles away and is capped with material rich in hematite) and the more distant Clay Unit. Both were initially identified from orbit by the Compact Imaging Spectrometer on board the Reconnaissance Orbiter. Due to their compositions, these younger units are likely to have formed in wet environments and may yield additional data about the moist environments on ancient Mars which could have provided conditions favorable for microbial life.

Meteor Showers

October Meteor Showers include the Camelopardalids (10/5), the Draconids (10/8), the Taurids (10/10), the Delta Aurigids (10/11), the Epsilon Geminids (10/18), the Orionids (10/21), and the Leo Minorids (10/24). All but 3 are minor showers. The Draconids consist of debris shed from from Comet 21P/Giacobini-Zinner during previous passages. They are extremely variable ranging from 10 to 60 meteors per hour and occasionally storming to 100’s to 1000’s per hour. The Taurids (~5 per hour) are from Comet 2P Enke and the Orionids (~20 to 70 meteors per hour in dark skies) are the remnants of Comet Halley.

Halloween

As with most of our holidays, the origin of Halloween is related to an astronomical event. It is the eve of All Saints Day on Nov. 1st, a cross-quarter day, half way between the Autumnal Equinox and the Winter Solstice. Some cultures recognized transitions between seasons on the cross-quarter days half way between the equinoxes and solstices (the “quarter” days). The quarter days were considered to be the middle of each season. The cross-quarter days include Candlemas (Groundhog Day), Beltane (May Day), Lamas, and All Saints Day (Hallowmas or Hallow’s mass). Hallow’s can refer to saints, the relics of saints, or the shrines in which the relics are kept. Hallowmas was established to replace an ancient Celtic festival marking the end of summer when the dead were believed to arise for one night. People would commemorate the event by dressing up and acting like the undead.

Planet Plotting

Venus (-3.9 to -4.0) is visible in the southwestern sky after sunset in October. During the month, it will move from Libra, through Scorpius, and into Ophiuchus and will be about 3.0° south of Saturn at 4AM EDT on the 30th.

Saturn (+0.5 to +0.6) and Mars (+0.1 to +0.3) spend October in the southwestern sky in Ophiuchus and Sagittarius respectively. In early October they set before 10PM EDT and by the end of the month they set about 8PM EDT.
Neptune (+7.8) in Aquarius and Uranus (+5.8) in Pisces rise before sunset and set in the wee hours after midnight. Uranus is at its brightest of the year on the 15th at 1PM EDT when it is at opposition.

Jupiter (-1.7) in Virgo moved into the morning sky after its conjunction with the Sun on Sept. 26th. It rises slightly after 7AM EDT in early October and after 5:30AM EDT by the end of the month. Mercury (-0.9 to -1.4) rises in Leo at about 5:30AM EDT at the beginning of the month and will be found less than a degree NNE of Jupiter on the morning of the 11th. It grows brighter as it moves through Virgo and rises with the Sun after 7AM EDT at month’s end. After Superior Solar Conjunction at noon on the 30th, Mercury will move into evening skies.

Planet Constellation Magnitude Planet Passages

Sun………….Virgo…………-26.8………….New Moon, 10/30, …………………………………………………………………1:38AM EDT Mercury…Leo,Virgo….-0.9 to -0.1.4…….Superior Conjunction, …………………………………………………………….10/27, Noon EDT ……………………………………………………….Jupiter, 0.9°S …………………………………………………………10/10, Midnight EDT Venus..Libra, Scorpius, Ophiuchus..-3.9 to 4.0….Saturn, 3.0°N …………………………………………………………….10/30, 4AM EDT
Mars…. .Sagittarius..+0.1 to +0.3
Jupiter ………Virgo………….-1.7…………….Mercury, 0.9°N …………………………………………………………10/10, Midnight EDT Saturn…….Ophiuchus……..+0.5 to +0.6….Saturn, 3.0°S ……………………………………………………………..10/30, 4AM EDT
Uranus…….Pisces…………..+5.7
Neptune…..Aquarius……….+7.8 to +7.9

October Moon

The New Moon of October is on the 30th at 1:38AM EDT. The New Moon is the beginning of Lunation 1161 which ends 29.86 days later with the New Moon of November 29th at 7:18AM EST.

The Full Moon in October in Pisces occurs at 12:23AM EDT on the 16th. It is normally called the “Hunters Moon”. It was also the “Hunters Moon” for the Celts and Chinese mark the October Moon as the “Kindly Moon”. To Medieval English, it was the “Blood Moon” and the Anishinaabe (Odawa and Ojibwe) people of northern Michigan celebrate it as “Binaakwe-giizis” (Falling Leaves Moon).

It was also called the “Hunters Moon” in Colonial America. After the Harvest Moon in the previous month when the fields were reaped, hunters moved into the fields seeking game feeding on the crop remants and hiding in the stubble. The products of the hunt resupplied their larders in preparation for the oncoming winter.

The Moon is at the apogee position in orbit (maximum orbital distance) at 252,336 miles (63.67 Earth radii) from Earth on the 4th at 7:03AM EDT. It is again at aphelion at 252,688 miles (63.76 Earth radii) from Earth on the 31st at 3:29PM EDT. Perigee distance (closest to Earth) is 222,364 miles or 56.11 Earth radii on the 16th at 7:34PM EDT. Since Full Moon occurs when the Moon is closer to Earth than usual, the Full Moon appears as a large “Supermoon”. The Full Moon lineup of the Sun, Earth, and a nearby Moon will force seaside residents to be on the alert for unusually high tides which will also result in higher than normal “tidal bore waves” moving farther upstream in rivers draining into the sea.

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

Sun…………Virgo…………..-26.8…………1:38AM EDT, 10/30 ……………………………………………………………New ~ 0 days Mercury……Virgo……………-1.4………..4.2°NNE,1PM EDT, 10/30 ……………………………………………………..Waxing Crescent ~ ………………………………………………………………..0.18 days Venus………Virgo……………-3.9………..5.0°N, 1PM EDT, 10/3 ……………………………………………………..Waxing Crescent ~ …………………………………………………………………3.33 days Mars……Sagittarius…………+0.1……….7.0°N, 8AM EDT, 10/8 ………………………………………………………Waxing Crescent ~ ………………………………………………………………..8.12 days Jupiter……..Virgo…………….-1.7……….0.4°N, 6AM EDT, 10/28 ……………………………………………………..Waning Crescent ~ …………………………………………………………………28.04 days Saturn…….Ophiuchus………+0.5………..4.0°N, 4AM EDT, 10/6 …………………………………………………….Waxing Crescent ~ ……………………………………………………………….5.96 days Uranus…….Pisces……………+5.7……….3.0°S, 10PM EDT, 10/15 …………………………………………………….Waxing Gibbous ~ ……………………………………………………………….15.71 days Neptune……Aquarius……….+7.8………1.2°N, 2AM EDT, 10/13 …………………………………………………….Waxing Gibbous ~ ……………………………………………………………….12.87 days 

08/4/2016
August Skies by Dick Cookman

Highlights: Comet Journal, Martian Landers, Meteor Showers, Planet Plotting, August Moon

Focus Constellations: Perseus, Cassiopeia, Andromeda, Pegasus, Cepheus, Cygnus, Lyra, Aquila, Ophiuchus, Hercules, Draco, Ursa Minor, Ursa Major, Bootes

Comet Journal

July’s brightest comet is Comet C/2013 X1 (PanSTARRS). It is visible in larger binoculars at 9th magnitude in southern hemisphere skies south of the tail of Hydra in August. It achieved naked eye visibility in dark skies in June when closest to Earth and was closest to the Sun at perihelion in April. During the last part of 2016 it will rapidly decrease in magnitude as it retreats to the outer Solar System well beyond the orbit of Pluto.

Mars Landers

Opportunity is on the rim of Endeavour Crater exploring a large valley cutting through the rim. The rover is nearing the completion of its investigation within Marathon Valley and is engaged in one of its final big in-situ campaigns in the valley. As the rover examined the center of the area where the spectral signatures of clay-bearing rocks on the valley floor were detected from orbit, streaks of red-toned, crumbly material were found on the valley’s southern flank. The science team chose to investigate this apparently weathered material. The rover approached exposures of it to prepare for using the Rock Abrasion Tool, called the RAT. This tool grinds away a rock’s surface to expose the interior for inspection.

“What we usually do to investigate material that’s captured our interest is to find a bedrock exposure and use the RAT,” Squyres said. “What we didn’t realize until we took a close-enough look is that this stuff has been so pervasively altered, it’s not bedrock. There’s no solid bedrock you could grind with the RAT.”

Instead, the rover exposed some fresh surfaces for inspection by scuffing some of the reddish material with a wheel.

Squyres said, “In the scuff, we found one of the highest sulfur contents that’s been seen anywhere on Mars. There’s strong evidence that, among other things, these altered zones have a lot of magnesium sulfate. We don’t think these altered zones are where the clay is, but magnesium sulfate is something you would expect to find precipitating from water. “Fractures running through the bedrock form conduits through which water could flow, transport soluble materials, and alter the rock to create the pattern of red zones that we see.”

From Sol 4404 (June 14, 2016) through Sol 4445 (July 25, 2016) Opportunity traveled 0.12 miles achieving a total distance on Mars of 26.75 miles (43.05 kilometers). The solar array energy production averaged 635 watt-hours per day, a rather remarkable level for the middle of the Martian winter.

Curiosity began July by putting itself into safe standby mode
on the 2nd. Since the most likely cause is thought to be a software mismatch in onboard communication of image data, mission scientist will change modes of communication. Let’s hear it for redundant systems. Despite the temporary shut down, NASA approved a two year extension starting on Oct. 1st for the mission which determined in its 1st year that freshwater lakes and rivers on Mars provided environmental conditions suited to microbial life 3 billion years ago at a time when Earth provided similar conditions and hosted abundant microbes. The rover found sulfur, nitrogen, oxygen, phosphorus, and carbon — the key ingredients necessary for life in its 2012-2013 investigations of the “Sheepbed” mudstone in Yellowknife Bay. The investigations also revealed clay minerals and low levels of salt suggesting deposition from fresh water with moderate oxidation levels which was of neutral acidity or moderately alkaline. The spectrum of oxidized through non-oxidized chemicals provided a chemical energy gradient like that preferred by many organisms on Earth.

The current red color of Mars is due to strongly oxidized iron and other atoms, the gray colors exhibited in many of the drilling samples suggest much lower oxidation levels which would be more conducive to life. Curiosity is investigating older rocks than those examined by Opportunity which appear to have been deposited from saline water with much more acidity creating a very limited chemical energy gradient with little energy availability for lifeforms. The high salinity would have impeded microbial metabolism for any life which could survive in the acidic environment indicating that by the time the rocks investigated by Opportunity were formed, environment conditions favoring life had already deteriorated.

Curiosity reached Mars in August, 2012 and, after its 1st year discoveries, spent 3 years investigating the exact nature of the ancient wet environments in Gale Crater. The next phase of study is focused on the geologic evolution recorded in the progressively younger layers of rock preserved in Mt. Sharp which the rover is currently ascending. Mission scientist hope to determine the nature and cause of the environmental changes which resulted in the transition of a wet Mars to the dry, inhospitable conditions currently exhibited. Such information may provide indications of how a similar transition may be avoided on Earth.

Meteor Showers

The best meteor shower of the Summer started in mid-July and will continue until late August. The Perseids will peak on the 12th and may be stronger than normal. The Perseid meteors are bits of dust, sand, pebbles, and rocks strewn along the orbit of Comet 109P Swift-Tuttle which last passed through the inner solar system in 1992. The comet’s orbit also passes by that of Jupiter. The last time Jupiter was at the location where the two orbits are in closest proximity, its gravity gathered cometary debris in the comet orbit into a clump which has since moved to the location where the comet orbit and that of Earth are in close proximity (the debris shares the same orbit as the comet, so it moves at a similar rate).

On the 12th, Earth will arrive at this location and as we plunge through the clump, an outburst of meteors may fill the night sky. Although normal Perseid rates are about 50 per hour in dark skies, meteor observers and scientists are speculating that rates may approach 150 to 200 per hour. The Perseids are typically bright, fast, and colorful meteors producing long trails with occasional flares at trail’s end. The slightly gibbous waxing Moon will rise in the afternoon and will set after midnight leaving a glare free sky in the wee hours before dawn when North America is orbiting headfirst into the river of meteoric debris.

The Kappa Cygnids on the 17th and the Aurigids on the 31st are much weaker showers typically producing about 5 meteors per hour.

Planet Plotting

The western evening sky in August hosts the planets Mercury (-1.6 to -0.2), Venus (-3.9), and Jupiter (-1.9 to -1.7) in Leo and Virgo. In early August they are lined up with a very bright Venus closest to the horizon yet still very visible in the glare of the setting Sun. Bright Jupiter is highest, with Mercury in between and almost lost in the glow of sunset. Mercury is highest in the sky on the 16th when at maximum eastern elongation (27° from the Sun) but will have to complete with an almost full waxing gibbous Moon. During August, Jupiter will drop closer to the horizon as Venus climbs higher and appears to approach the giant planet. The southern sky has Mars (-1.4 to -0.8) in Libra and Scorpius and Saturn (+0.2 to +0.3) in Ophiuchus while Neptune (+7.8) in Aquarius is rising in the east. The predawn hours display Neptune in the southwest and Uranus (+5.8) in Pisces in the south.

There are three planetary conjunctions at the end of the month when the Moon is in its waning crescent phase. Mars passes within 4° of Saturn at 2PM EDT on the 25th, and, on the 27th two more conjunctions occur. Venus is 5° from Mercury at 1AM EDT and appears very close (0.07°) to Jupiter at 6PM EDT.

Planet Constellation Magnitude Planet Passages

Sun…………..Cancer, Leo…………..-26.8…….New Moon, 8/2, …………………………………………………………………4:45PM EDT Mercury…….Leo, Virgo………-0.2 to +1.1…..Max. East Elongation, ……………………………………………………………8/16, 5PM EDT …………………………………………………………..Venus, 0.5°N, …………………………………………………………….8/27, 1AM EDT Venus………..Leo, Virgo……….-3.8………………..Mercury, 0.5°S, …………………………………………………………….8/27, 1AM EDT …………………………………………………………..Jupiter, 0.07°S, …………………………………………………………….8/27, 6PM EDT Mars…………Libra, Scorpius……-0.8 to -0.3………Saturn, 4°N, …………………………………………………………….8/25, 2PM EDT
Jupiter …………..Leo, Virgo………….-1.7…………….Venus, 0.07°N, …………………………………………………………….8/27, 6PM EDT Saturn……………Ophiuchus……..+0.3 to +0.5………Mars, 4°S, …………………………………………………………….8/25, 2PM EDT
Uranus…….. ……Pisces…………..+5.8 Neptune………….Aquarius……….+7.8

August Moon

The New Moon of August on the 2nd at 4:45PM EDT is the beginning of Lunation 1158 which ends 29.51 days later with the New Moon of September 1st at 5:03AM EDT.

The Full Moon in August is in Aquarius and occurs at 5:27A M EDT on the 18th. It is known as the “Grain or Green Corn Moon” and was the “Dispute Moon” for the Celts. Chinese celebrate the August Moon as the “Harvest Moon” and to Medieval English it was the “Corn Moon”.

It was called the “Dog Day’s Moon” in Colonial America, a reference that traces its origin to the ancient Egyptians who designated the time following the helical rising of Sirius (the “dog star” in Canis Major) as the “dog days”. The helical rising of Sirius occurred when Sirius rose just before the Sun and was a calendar marker for the Egyptians because flooding of the Nile was soon to follow. Sediment deposited by the flood renewed the soil, allowing the continuous cropping of the same region necessary for survival of their civilization. The helical rising permitted the development of the first accurate annual calendar which replaced earlier lunar calendars based on months.

The Moon is at the apogee position in orbit (maximum orbital distance) at 251,197 miles (63.38 Earth radii) from Earth on the 9th at 8:05PM EDT. Perigee distance is 228,074 miles or 57.55 Earth radii on the 21st at 9:19PM EDT.

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

Sun………….Cancer………..-26.8…………4:45PM EDT, 8/2 ……………………………………………………………New ~ 0 days Mercury…….Leo……………..-0.2…………..0.6°S, 6PM EDT, 8/4 ……………………………………………………..Waxing Crescent ~ ………………………………………………………………..2.05 days Venus……….Leo……………..-3.8………..3.0°S, 2AM EDT, 8/4 ……………………………………………………..Waxing Crescent ~ …………………………………………………………………1.39 days Mars………..Scorpius……….-0.6…………..8.0°N, 6PM EDT, 8/11 ……………………………………………………..Waxing Gibbous ~ ………………………………………………………………..9.05 days Jupiter……..Virgo………..-1.7…………..0.2°S, Midnight EDT, 8/5 ……………………………………………………..Waxing Crescent ~ …………………………………………………………………2.30 days Saturn…….Ophiuchus……….+0.4………..4.0°N, 8AM EDT, 8/12 …………………………………………………….Waxing Gibbous ~ ……………………………………………………………….9.64 days Uranus…….Pisces………….+5.8………..3.0°S, 6AM EDT, 8/22 …………………………………………………….Waning Gibbous ~ ……………………………………………………………….19.55 days Neptune……Aquarius………..+7.8………1.1°N, 8AM EDT, 8/19 …………………………………………………….Waning Gibbous ~ ……………………………………………………………….16.64 days 

06/10/2016
June Skies – by Dick Cookman

Highlights: Comet Journal, Martian Landers, Meteor Showers, Summer Solstice, Planet Plotting, June Moon

Focus Constellations: Lynx, Camelopardalis, Cassiopeia, Cepheus, Draco, Ursa Minor, Ursa Major, Bootes, Hercules, Lyra, Cygnus, Aquila, Ophiuchus, Libra, Virgo, Coma Berenices, Leo, Cancer

Comet Journal

Comet 252P/LINEAR (2016) is between Ophiuchus and Serpens Caput at magnitude 10.0 as it circles through Ophiuchus in June. It is rapidly dimming and will recede beyond Jupiter’s orbit this summer.

Comet C/2013 X1 (PanSTARRS) is approaching 6th magnitude in southern hemisphere skies. It passed through perihelion on April 20th and will pass within 56 million miles of Earth between the orbits of Earth and Mars on June 21st. It will appear south of Sagittarius in Telescopium in morning skies for observers in southern United States.

Mars Landers

Opportunity is still tooling around Mars even though its long time compatriot Spirit is silent and was last heard from in March 2010 as it was positioning itself to survive the upcoming winter. Its demise after 6 years on Mars was not a failure but the conclusion of a spectacular series of successes! Despite having to overcome tremendous challenges, Spirit exceeded its planned mission lifetime by more than 20 times as it explored Gustev Crater, a vast impact scar filled with sediments deposited in an ancient lake. The rover uncovered rocks formed from the sediments which had high concentrations of carbonate, a substance requiring wet, non-acidic depositional environments. Although previous evidence indicated that there were many areas of wet, acid conditions, this was the first indication that Mars once had water which may have hosted abundant life. Spirit also discovered evidence for ancient volcanism in contact with water and found an almost pure silica deposit like those on Earth which are found associated with hydrothermal veins and hot springs, prime acid loving microbe environments.

On May 1, 2009 Spirit drove into the soft sand west of Home Plate at Troy, its final resting place. After the science team spent months trying to free the rover, it was converted to a stationary research station in January, 2010. The last contact occurred on March 22nd when Spirit was put into hibernation for the winter. It never woke again despite the magnificent efforts of the science team which concluded on May 25, 2011.

Opportunity is exploring Marathon Valley on the rim of Endeavour Crater investigating rock outcrops for the presence of clay minerals which may contain evidence of ancient life. It is currently engaged in seeking out specific rock outcrops to find evidence for clay minerals. Between Sol 4357 (Apr. 26, 2016) and Sol 4391 (May 31, 2016) the rover traveled about 0.1 miles as it moved from target to target at an outcrop designated as “Pierre Pinaut” collecting evidence with its Navigation and Panoramic cameras and performing Alpha Particle X-ray Spectrometer (APXS) measurements. At each drive location, the rover collects a 360-degree Navigation Camera (Navcam) panorama plus targeted multi-filter (color) Panoramic Camera (Pancam) panoramas.

During the interval, the solar array energy production ranged between 636 and 672 watt-hours/day, sufficient energy for full operations. Total distance traveled by Opportunity on Mars in the last 12+ years is 26.59 miles (42.79 kilometers).

After a torturous crossing, Curiosity finally descended the west flank of Naukluft Plateau, a 1/4 mile wide terrain of sandstone composed of ancient lithified sand dunes carved into ridges and knobs by millions of years of wind erosion.

Current plans are to cross the Bagnold Dune Field by heading south between isolated dunes on the east and the Murray Buttes on the west. From Sol 1355 to 1356, the rover conducted numerous observations with its ChemCam of targets in the Murray formation and made multispectral observations of the contact between the Murray and Stimson units. It resumed driving on Sol 1357 (May, 29, 2016) then stopped to conduct a drilling campaign of the Oudam bedrock target from Sol 1360 through Sol 1365 (June 6, 2016). Plans are to then continue the journey ascending Mt. Sharp.

Meteor Showers

The Bootid Meteor shower peaks on June 27th during the 3rd quarter Moon which rises in the east about midnight. Meteor counts are normally less than 5 per hour but reach 100 to 150 per hour in good years. The meteors appear to come out of Bootes which is in the western skies after midnight when more meteors are visible because we are on the leading face of the Earth as it plunges through the river of debris scattered in space from previous passages of Comet Pons-Winnecke which circuits the Sun every 6.37 years. It last passed through perihelion in Jan. 2015.

Summer Solstice

The Summer Solstice is on June 20th at 6:34PM EDT when the axis of the Earth is tilted toward the Sun at its maximum angle and the Sun crosses the sky during the day at its highest annual elevation above the southern horizon. Before 1975, the June solstice was on the 21st or 22nd, then on June 21st until 2012, after which it occurred on the 20th or 21st. On the 20th at solar noon the Sun is at the zenith at 23.5° N. latitude (Tropic of Cancer) and is 47° above the south horizon at 66.5° N. latitude. Those living farther north are in the land of the midnight Sun and those south of 66.5°S experience no daylit hours. At 45° N. latitude the Sun appears 68.5° above the southern horizon at solar noon.

Even though the longest day of the year (and the shortest night) for northerners is the June solstice when the Sun is highest in the sky, the Earth is farther from the Sun than normal because it is approaching the early July farpoint (aphelion) in its orbit. The resulting intensity of sunlight perpendicular to the Sun’s rays is actually lower in June and July than in April and May, a happy circumstance for the Spring warm-up. Solar distance varies from 91.5 million at perihelion in January to 94.5 million at aphelion, but limited hours of daylight compensate for solar proximity in January as extensive daylight compensates for the more distant July Sun.

Of course, the opposite relationship exists for the southern hemisphere which theoretically producing hotter summers and cooler winters were it not for moderation by more extensive oceans in the southern hemisphere in contrast to the large area of continental land mass in the northern hemisphere. Plate tectonics will alter this land/ocean relationship in the future and change everything again for patient observers as the Sun joins in by doubling its output over the next few billion years.

Some astronomers hypothesize that the Sun is experiencing more stability than usual. There are other sun-like stars that exhibit significant changes in output, abruptly increasing, then shutting down to minimal intensity just a quickly. Many giant stars exhibit much more extreme changes, sometimes on a weekly basis, but the Sun is thought to be in a long, stable stage of life, gradually increasing in output. Our problem is that deep sky astronomical investigation is only ~200 years old and we don’t have the long term data to really know the definition of stable when it comes to stars.

If you wake one morning and notice a very dim orb rising in the east, don’t worry, dress warmly. If a megabright blazingly hot crescent peaks above the eastern horizon, call off that southern trip and consider the Yukon.

Planet Plotting

June’s morning planets include Mercury (+0.8 to -1.5), Uranus (+5.9) in Pisces, and Neptune (+7.9) in Aquarius. Mercury reaches greatest western elongation on the 5th when it is 24° from the Sun and 6° above the eastern horizon an hour before sunrise. Venus was a morning planet in May, moves through Superior Conjunction on the other side of the Sun on the 6th, and is out of sight throughout month before moving into evening skies in July.

Three planets and a half dozen+ 1st magnitude stars decorate evening skies in June. Mars (-2.0 to -1.4) in Libra is almost as bright in early June as it was at opposition in May. The crescent and new phases of the Moon produce much less competing glare than in May. Mars in the southeast is about as bright as Jupiter (-2.1) in Leo in the southwestern evening sky and outshines both Saturn (+0.2) in Ophiuchus and red supergiant Antares(+1.0) in Scorpius. Saturn’s Opposition is at 3AM EDT on the 3rd when it is at its brightest magnitude of 2016. Mars, Saturn, and Antares near the southeastern horizon after sunset form a conspicuous triangle which moves into southern skies in the late evening as Jupiter sets in the west.

Planet Constellation Magnitude Planet Passages

Sun….Taurus, Gemini……..-26.8……………..New Moon ………………………………………………………6/4, 11PM EDT
Mercury..Taurus, Gemini…+0.8 to -1.5……Max. West Elong. ……………………………………………………….6/5, 5AM EDT
Venus…Taurus, Gemini
Mars…..Libra…………………-2.0 to -1.4
Jupiter..Leo……………………-2.1 to -1.9
Saturn..Ophiuchus…………..+0.0 to +0.1….Opposition, ……………………………………………………….6/3, 3AM EDT
Uranus…Pisces………………..+5.9
Neptune..Aquarius…………..+7.9

June Moon

The New Moon of June 4th at 11PM EDT marks the beginning of Lunation 1156 which ends 29.33 days later with the New Moon on July 4th at 7:01AM EDT.

June’s Full Moon is in Ophiuchus and occurs at 7:02AM EDT on the 20th. It is known as the Flower Moon, Rose Moon, Strawberry Moon, or Honey Moon and was referred to as the “Rose Moon” in Colonial America. Celts referred to it as “Moon of Horses” and Chinese call it “Lotus Moon.” To Medieval English it was the “Dyan Moon” and Anishinaabe (Chippewa and Ojibwe) of northern Michigan celebrate it as “Odemiini-giizis” (Strawberry Moon).

Perigee distance is 224,402 miles or 56.62 Earth radii on the 3rd at 6:55AM EDT. The Moon is at the apogee position in orbit (maximum orbital distance) at 251,670 miles (63.50 Earth radii) from Earth on the 15th at 8:00AM EDT.

Planet Constellation Magnitude Moon Passage Moon Phase/Age

Sun………….Taurus………-26.8………….11PM EDT, 6/4 ……………………………………………………………….New ~ 0 days
Mercury…….Taurus……..+0.7…………….0.7°S, 6AM EDT, 6/3 ………………………………………..Waning Crescent ~ 27.60 days
Venus……….Taurus……..-4.0…………….4.9°S, 10PM EDT, 6/4 …………………………………………Waning Crescent ~ 29.27 days
Mars………….Libra……….-1.7…………..7.0°N, 6AM EDT, 6/17 ………………………………………….Waxing Gibbous ~ 12.14 days
Jupiter……….Leo………….-2.0…………..1.5°S, 4PM EDT, 6/11 ………………………………………….Waxing Crescent ~ 6.71 days
Saturn…….Ophiuchus…..+0.1…………..3.0°N, 8PM EDT, 6/18 ………………………………………….Waxing Gibbous ~ 13.88 days
Uranus……….Pisces……..+5.9…………..2.0°S, 10AM EDT, 6/1 ………………………………………….Waning Crescent ~ 25.77 days
Uranus……….Pisces……..+5.9……………3.0°S, 7PM EDT, 6/28 ………………………………………….Waning Crescent ~ 23.83 days
Neptune……Aquarius……+7.9……………1.2°N, 9PM EDT, 6/25 ………………………………………….Waning Gibbous ~ 20.92 days 

04/7/2016
April Skies by Dick Cookman

Highlights: Comet Journal, Martian Landers, Meteor Showers, Mother Goose and the Headlands, Planet Plotting, April Moon

Focus Constellations: Camelopardalis, Ursa Major, Ursa Minor, Draco, Cepheus, Cassiopeia, Perseus, Auriga, Taurus, Gemini, Cancer, Lynx, Leo, Coma Berenices, Canes Venatici, Bootes, Hercules

Comet Journal

There are two comets at or approaching naked eye visibility in April night skies. Comet 252P/LINEAR (2016) is between magnitudes 5 and 6 and near its peak brightness after passing through perihelion last month when it was about 3 million miles south of Earth. It moved into northern skies at the end of March and will circle through Ophiuchus during the Spring and early Summer as it moves outward toward and beyond Jupiter’s orbit.

Comet C/2013 X1 (PanSTARRS) is about 8th magnitude between Pisces and Aquarius and is getting brighter as it approaches perihelion on the 20th. In mid-June, it may reach 6th magnitude when passing within 56 million miles of Earth between the orbits of Earth and Mars. It will appear south of Capricornus in morning skies.

Mars Landers

Opportunity is up on the steep slopes of “Knudsen Ridge” in Marathon Valley on the rim of Endeavour crater. On Sol 4297 (Feb. 24, 2016), the rover performed its first contact measurements of an exposed rock named “Charles Caugee” and followed that up on Sols 4299 – 4302 by moving 6.0 meters uphill toward another target “Pvt. Joseph Whitehouse”. The gravely slopes in excess of 30° prevented further progress toward the target despite numerous attempts in the following 11 sols so the effort was abandoned. Even though Opportunity failed in its attempts to reach the target, the interval provided valuable information as the rover was able to conduct a wide variety of remote sensing measurements of the surrounding environments.

On Sol 4316 (March 15, 2016), Opportunity moved further downhill, driving about 22 feet (6.7 meters) north to set up for a longer drive towards the next science target along “Knudsen Ridge”. On Sol 4320 (March 19, 2016), the rover drove about 31 feet (9.5 meters) to the southwest towards areas with spectral signatures of phyllosilicate clays from satellite measurements. Supporting Navcam and Pancam panoramas were collected after the drive to prepare for the next drive. On Sol 4323 (March 22, 2016), Opportunity headed due west about 41 feet (12.5 meters).

From Sol 4325 (March 24, 2016) through Sol 4330 (March 29, 2016), the rover drove 142 feet (44 meters) to reach the clay area and proceeded to document the terrain with extensive Pancam color (multi-filter) panoramas. As of Sol 4330 (March 29, 2016), the solar array energy production has increased to 650 watt-hours and the total distance Opportunity has traveled on Mars is 26.55 miles (42.74 kilometers).

On Sol 1275 (Mar. 5, 2016), Curiosity reached the finely laminated rock at the boundary between the “Murray Formation” and the overlying “Stimson Formation”, a short distance from a target with rather interesting knobby nodules. The next 6 sols were devoted to collection of nodule laser data with the ChemCam and then the rover ascended the slope from the edge to the top of the “Stimson Formation” which is called the “Naukluft Plateau”. Mission scientists planned to cross the rugged terrain of the plateau and to collect data from various targets in the process. The rover drove for the next 20 sols and by Sol 1302 traveled over 200 meters over the plateau making numerous atmospheric, panoramic and sedimentary structure observations along with bedrock outcrop chemistry analyses.

Meteor Showers

The best meteor shower in April is the Lyrids in the predawn hours of the 22nd which, sadly, coincides with the night of the Full Moon. One to two hours before sunrise, the Moon will be in the western sky and Lyra will be high the south at the best viewing time for the shower which normally displays fairly bright meteors that may stand out in the moonglow. The shower occurs when Earth plunges through the trail of debris shed from Comet C/1861 Thatcher, last seen 155 years ago.

Mother Goose and the Headlands

Mary Stewart Adams is the program director for the Headlands Dark Sky Park near the straits of Mackinaw in Emmet County, Michigan. She is an English literature graduate from the University of Michigan who led the initiative to have the International Dark Sky Society in Tucson, Arizona recognize the Headlands as one of the first ten International Dark Sky Parks in the world in 2011. Now there are 20 and the Headlands is the only recognize dark sky park in Michigan.

Mary is a renowned expert on constellation stories and mythology, presenting the role of sky observation in the development of literature and the cultural history of humanity’s relationship to the night sky. Many writers utilized celestial events as inspiration for their creations.

As an example, Enerdyne sponsored the “Midwest Space Fest” in the Fall of 2013 where she presented a wonderful story about the inspiration for the Mother Goose tales.

The following is my attempt to communicate the sense of her story:

Hey diddle diddle, the cat (Leo) and the fiddle (Lyra), the cow (Taurus) jumped over the Moon (see 4/10 to 4/12 this month). The little dog (Canis Minor) laughed to see such a sight, and the dish (Milky Way) ran away with the spoon (Big Dipper).

She has a plethora of similar examples which she presents as part of the program offerings which she hosts at the Headlands and at events and conferences to which she is invited throughout the world. I highly recommend any opportunity to attend her presentations which are always educational and entertaining.

The Headlands is a county park supported by Emmet County and donations. Rental facilities are available in the park and there is camping, motels, and hotels in neighboring Mackinaw City.

As mentioned above, the Headlands has very active public program —— from star parties to viewing of celestial events, northern lights, birding events and activities, dances, hiking, winter sports, and other activities. As can be seen on their fascinating website at: www.midarkskypark.org, the park is located in one of the most spectacularly beautiful areas of the United States, on the shores of Lake Michigan.

Planet Plotting

April’s morning planets include brilliant Venus (-3.8 to -3.9) in Pisces and Neptune (+7.9) in Aquarius. Venus rises about an hour before sunrise in early April and draws closer to the Sun as it approaches solar conjunction in June. After the conjunction, Venus will make a brilliant reappearance in evening skies. Best viewing of Venus in April is early in the month before it drops too deeply into the glow of sunrise. It makes an attractive pairing with the waning crescent Moon in the predawn hours on April 6th. Uranus (+5.9) in Pisces reaches conjunction with the Sun on the 9th and rises slightly before the Sun in late April.

Mars (-0.5 to -1.4) moves from Scorpius and Ophiuchus in April and along with Saturn (+0.3 to +0.2) in Ophiuchus rises before midnight. They are low in the west before dawn. Mars is approaching opposition on May 22 when it will reach magnitude -2.1, outshining everything but Jupiter and the Moon in the night sky. By the last half of April it will already be close enough to see surface details in good 4 to 6 inch telescopes. The polar caps are subdued because the southern cap is tilted away from Earth and the northern cap is reduced by the long northern Martian summer. On the nights of the 24th – 26th, Saturn, Mars, Antares, and a large waning gibbous Moon make an impressive show in the southern sky in the hours after midnight.

Mercury (-1.5 to+2.7) is progressively higher in the west-northwest evening sky in April as it moves from Pisces into Aries putting on its best show for 2016. Jupiter (-2.4 to -2.3) in Leo passed through opposition last month and is still very bright. It dominates the southeastern evening sky, surpassed only by the Moon.

Planet……Constellation……Magnitude……Planet Passages

Sun…….Pisces, Aries….. -26.8………..New Moon, ……………………………………………………..4/7, 7:24PM EDT Mercury..Pisces, Aries… .-1.5 to +2.7
…………………………………………………..Max. East Elongation ……………………………………………………..4/18, 10:00AM EDT Venus…..Pisces………. …..-3.8 to -3.9 Mars…Scorpius, Ophiuchus…-0.5 to -1.4
Jupiter….Leo………………. .-2.4 to -2.3
Saturn….Ophiuchus……….+0.3 to +0.2 Uranus….Pisces…………………..+5.9……….Solar Conjunction ………………………………………………………..4/9, 5:00PM EDT
Neptune..Aquarius……………….+7.9

April Moon

The New Moon on April 7th at 7:24AM EDT marks the beginning of Lunation 1154 which ends 29.34 days later with the New Moon on May 6th at 3:30PM EDT.

April’s Full Moon is in Virgo and occurs at 1:24AM EDT on the 22nd. It was referred to as the “Planter’s Moon” in Colonial America. Celts referred to it as “Growing Moon” and Chinese call it “Peony Moon.” To Medieval English it was the “Seed Moon” and Anishinaabe (Chippewa and Ojibwe) of northern Michigan celebrate it as the “Iskigamizige-giizis(oog)” (Sugarbushing Moon).

Perigee distance is 221,931 miles or 56.00 Earth radii on the 7th at 1:36PM EST. This is the second closest perigee of 2016 and almost coincides with new moon, causing ocean tides to be higher than normal. The Moon is at the apogee position in orbit (maximum orbital distance) at 252,495 miles (63.71 Earth radii) from Earth on the 21st at 12:05PM EDT.

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

Sun………Pisces……..-26.8……………7:24AM EDT, 4/7 ……………………………………………………..New ~ 0 days Mercury…Pisces…………..-1.0………5.0°S, 7AM EDT, 4/8 …………………………………………Waxing Crescent ~ 0.98 days Venus……Pisces………..-3.8…………0.7°N, 4AM EDT, 4/6 …………………………………………Waning Crescent ~ 28.80 days Mars…….Ophiuchus…….-1.2……5.0°N, Midnight EDT, 4/24 …………………………………………Waning Gibbous ~ 16.69 days Jupiter……Leo…….-2.3…………2.0°S, 1AM EDT, 4/18
…………………………………………Waxing Gibbous ~ 10.73 days
Saturn..Ophiuchus…+0.2…………3.0°N, 3PM EDT, 4/25 …………………………………………Waning Gibbous ~ 18.32 days Uranus….Pisces…….+5.9………….1.9°SSE, 11AM EDT, 4/7 …………………………………………Waxing Crescent ~ 0.15 days
Neptune..Aquarius…+7.9…………1.9°N, 6AM EDT, 4/4 …………………………………………Waning Crescent ~ 27.50 days