Star Calendar – February 2015

Star Calendar

February 2015

Star Calendar Planets:

Moon is innocuously Full at a safe distance, but will be New only a few hours from perigee.

Mercury makes a feeble morning apparition this month and may be seen with the aid of the Moon on the 17th. Subsequent mornings will find Mercury by itself low in the ESE, somewhat below and to the right of brighter Altair.

Venus had a subtle meeting with Mercury last month. This month, chaperoned by the Moon, she meets very publicly with Mars on the equinoctial point on the 20th-21st.

Sun gives us noticeably longer days over the course of this month – by the end of February the sky is light 12 hours a day if one includes the bright sky of civil twilight. According to the Sun’s progress through the zodiac we are halfway to equinox on the 2nd, “Groundhog Day”, but according to the culminating height of the Sun, or, of the change in the length of daylight, the midpoint is on the 18th.

Mars meets the brilliant Venus this month, as mentioned above, and appears a little lower each evening. Mars is nevertheless progressing leftwards though, and crosses the vernal equinox point – staying above the equator now until November.

Jupiter is in opposition on the 6th. On the night of the 3rd – 4th the Full Moon will be nearby.

Saturn is more toward the south now at a reasonable pre-dawn hour. The Moon will be near on the 12th and 13th.

Comet Lovejoy has been a delight to watch as it passed the Pleiades in late January. Once found with binoculars it was easily discernible without them. February 5th, 6th, before the gibbous Moon rises, may afford a last glimpse before it fades away. Look in the evening, West, above the diamond of Pegasus and to the left of the “W” of Cassiopeia. Continue reading

Star Calendar – January 2015

Star Calendar

January 2015

Star Calendar Planets:

Moon follows a sinus path tipped 5 degrees to the ecliptic, which is itself tipped 23 Β½ degrees to the celestial equator. The phase of these two tipping curves slowly changes, a cycle of phase-shift taking 18.6 years. When the Moon and Sun’s (vernal) ascending nodes coincide (additive phase relationship) the Moon soars above, and plunges below, the equator with a declination range of 57 degrees – as in 2005-6. This year, some 9 years later, the curves instead subtract and we have a minimum range of declination for the Moon; being just 36-37 degrees (compared to the Sun’s steady 47 degrees). This is also referred to as a “minor lunar standstill”. Moon’s descending node will correspond with vernal equinox in March this year. For 2015, the very highest declination the Moon will achieve will be only 18 2/3 degree; on Jan 3rd.

Mercury sweeps up to meet Venus on the 11th and may be looked for in the early evenings of the following week with reasonable expectation if one has a good horizon in the WSW. Already by the 21st Mercury will be hard to find despite a helpful but very thin, young Moon nearby. February’s morning apparition will be poor but May’s will be the best for the year.

Venus continues her magnificent evening ascent at a stately pace. She will be an evening feature until June.

Sun is nearest earth on the 3rd and its disk is actually larger. Total solar eclipses are rarer in January; more common in July when more distant/smaller. The Sun also progresses faster against the backdrop of stars at this time of year.

Mars has a year 684 Earth-days long (or 668 Mars-days) during which it also has seasons. Martian solstice occurs on our Jan 11th, with the Martian North turned away from the Sun. Oddly the northern Martian winter is longer than the southern – as interpreted by the outbreak of reflective frost and dry ice at the respective poles. Martian seasons are more dramatically modified by their relationship to its apsides (proximity to the Sun) than Earth’s.

Jupiter is moving retrograde, approaching its maximum brightness for an opposition in Cancer early next month.

Saturn continues to dominate the SE before sunrise. The Moon will again pass very near on the 16th. Continue reading

Star Calendar – December 2014

Star Calendar

December 2014

Star Calendar Planets:

Moon crosses the line of Vernal Equinox while setting at around midnight as December begins, then is highest for the month on the 6th, rising (just Full) above Orion around 6:PM. On the 15th Moon crosses the Autumnal Equinox while rising around midnight and on the 21st finds its lowest position with the Sun.

Mercury will cross behind the Sun on the 8th and run ahead for an evening appearance in mediocre circumstances following Christmas.

Venus should begin to be visible in evening twilight around the middle of the month, or by around Christmas evening, in the SW. Mercury will then follow, vincinaly joining her by Jan.12th.

Sun was poised for a barrage of heavy solar weather as a persistent large spotty region wheeled around twice; but it seems to have held its breath just when aimed our way. It seems our goose is not cooked quite yet. The Sun is now breaking out in numerous spots – finally. The peak of this solar cycle has been remarkably late and mild thus far.

Mars was occulted by the Moon during its opposition 7 years ago on Christmas Eve. The complex relationship of planetary rhythms brings about another lunar/martian encounter on Christmas Eve – but not an occultation and not in syzygy. Just enjoy the pair in the SW as they follow the Sun down that evening; 5-7:30 PM. Mars is only mag. +1.1 now, similar in brightness to Deneb, but reddish.

Jupiter is as near as it will get to Regulus and is now coming straight toward us, brightening and greatly outshining Regulus. The pair will be rising at 9:PM by Christmas. Oddly that “straight toward” (or away) motion is called “stationary”; because it stops moving against the background stars. Retrograde (backward) motion begins the 9th and will accelerate as 2015 opens, reaching Cancer by February.

Saturn has fallen behind the Sun enough to be visible in the morning, not quite as bright as higher Arcturus. Looking in the SE on the 19th between 6: and 6:30 AM will enjoy the aid of a proximate meniscus Moon. Continue reading

Star Calendar – November 2014

Star Calendar

November 2014

Star Calendar Planets:

Moon ‘s syzygy/perigee is becoming less synchronous now so we will have a respite from tidal inundations for a while. The next large spring tides are expected in late February.

Mercury is at an advantageous position for viewing as the month begins. The not-so-great maximum elongation of 19 degrees on the 1st is to good advantage as the ecliptic is pretty steeply inclined to the eastern horizon in the morning these days.

Venus crosses paths with Jupiter in the obscurity of the Sun this month. Venus, briefly an evening star as 2014 began, was a morning star for most of this year and will reappear in the evening next month – to dominate that position for much of 2015.

Sun is pointing a very large and active sunspot at us as I write. This one should be easily visible to the eye (with the same protection appropriate for eclipse viewing, or with an image projected onto a screen with a lens or pinhole). This spot will rotate away from view on Nov. 1st, but may appear again, mid-month, in some metamorphosed fashion.

Mars will continue to set about three hours after the Sun all of this month and now appears as a “mere” 1st magnitude star, similar to Altair – which stands above him in the evening. Mars can be as bright as -3. and as dim as +1.6, but the range varies greatly from one synodic cycle to another as the maximal and minimal distances change a lot due to its orbital eccentricity and to the highly variable albedo of its ice caps and dust storms. The last opposition was maximally at -1.5, slightly brighter than the brightest star, Sirius. Mars just had a very close encounter with a comet that flew a mere 90,000 miles in front of its path, (perpendicular and south-to-north) – rather like having a bird fly across the windshield as one drives along.

Jupiter slackens pace in its approach to Regulus, coming to a halt in early December. Jupiter will now rise before midnight, but is still to be experienced as a feature of the morning sky.

Saturn crosses the far side of the Sun on the 18th and will become visible in the morning sometime during Advent. Continue reading

Star Calendar Addenda – October 2014

Comet Siding

Comet Siding

Comet Siding Spring approaching Mars – photo from Australia by Damian Peach. Better (bigger) photo at:

Now THAT’S an image with dynamic range!Β Β  (NASA’s version is composite.)

The Sun, Oct. 16 – 24, 2014 as sunspot 2192 develops:

Sun Spot 01 Sun Spot 02 Sun Spot 03

Sun Spot 04 Sun Spot 05 Sun Spot 06

Sun Spot 07 Sun Spot 08 Sun Spot 09

Star Calendar – October 2014

Star Calendar

October 2014

Star Calendar Planets:

Moon and Earth play hit-or-miss with their shadows this month. The Moon sets an hour before sunrise on the 8th,just as it is engulfed by the shadow of the earth. Two weeks later, on the 23rd, we just miss a partial Sun eclipse because the Moon’s shadow approaches just as the Sun sets. Those substantially west of here will have an annular solar eclipse. The first sighting of the Moon in Egypt, following this event begins the Islamic year 1436 A.H.

Mercury pulls a rapid switcheroo this month, moving from evening to morning, and will have a decent showing near the end of this month. He is stationary to retrograde on the 4th, crosses the nearside of the Sun on the 16th, and reverts to normal motion on the 25th.

Venus makes a more lugubrious counter-switch and is invisible all month as she crosses the farside of the Sun on the 25th.

Sun gives us another hour and eighteen minutes less daylight over the course of this month. U.S. “Daylight Time” does not end until November 2, but the clocks are turned back in Europe on the 26th of this month – probably because the center of population there is further north.

Mars has passed Antares and relaxes into the wintry realms of Sagittarius while slightly dimming. Mars is above the horizon fewer than 9 hours a day this month – rising after 11:AM, setting around 8:PM. Mars crosses the winter colure on the 26th and will emerge from below the celestial equator next on Feb. 21, 2015.

Jupiter crosses into Leo on the 14th and is seen gradually nearer Regulus, both being higher each morning. He is still well north of the celestial equator and will not cross south of it for another two years.

Saturn eventually succumbs to the overtaking Sun and will not be seen again until some morning in late November. Saturn is in the midst of a long decline into the lower realms of the sky, not crossing the winter colure until Dec. 2017.

Uranus is in opposition and at its brightest this month. It should be visible with binoculars as a slightly greenish spot in Pisces, appearing in the SE about halfway up the sky, and below Alpheratz of the Square of Pegasus around 10 PM. It is necessary to avoid a moonlit sky, so looking after the 14th or so would be best. This is an object at the threshold of perception – theoretically a rare naked-eye object – but somehow missed by the keen observers of antiquity. Most people still never see it in their lifetime. Continue reading

Star Calendar – October 2007

Star Calendar

October 2007

Star Calendar Planets:

Mercury will sneak past the near side of the Sun (inferior conjunction) on Oct 23, then rush to the eastern morning sky in the end of the month. On November 7 it will appear to the left of Spica, just below and to the left of the waning crescent moon.

Venus shines brightly at about the same height at a given time each morning all month. Watch Regulus and Saturn rise higher and higher each day. On October 7th the waning Moon will join them. Venus waxes gibbous by the end of the month, but becomes more distant too.

Mars makes its longest path across our sky on October 1st and is highest at 5:15AM. Look above Betelgeuse of Orion. Mars is now closer to us than is the sun and it brightens as it draws ever closer and slows its movement against the stars. Watch for the Orionid meteors radiating from the vicinity on or about the 21st .

Jupiter remains in Ophiucus and accelerates its direct motion as it begins to fade. By month’s end it will be noticeably lower in the evening sky.

Saturn appears relatively dim in the eastern morning sky and will create an interesting series of triangles with Venus and Regulus all month. Continue reading

Star Calendar β€” September 2007

Star Calendar

September 2007

Star Calendar Planets:

Mercury will make a poor appearance in the western evening sky in mid-September. It will dash to the eastern morning sky by late October.

Venus will quickly rise into the eastern pre-dawn sky in September and will shine beside Regulus and Saturn by early October. On October 7th the waning Moon will join them.

Mars rises in the middle of the night in the horns of Taurus as September opens. It rises earlier in the evening and brightens as the weeks pass. Mars makes its highest and longest path across our sky on October 1st when it is of Betelgeuse of Orion – best seen in the south at about 6:00 AM.

Jupiter lingers in Ophiucus above Antares and is in the south at sunset as September begins. It slowly accelerates its direct motion and fades eastward toward the setting Sun.

Saturn appears close to Regulus in the eastern morning sky in mid-September. It may be visible under the waning Moon on September 9th and will have a sojourn with Venus a month later.

As seen from the Apollo 15 landing site; central Earth-side of the Moon and about 25Β° north of the Moon’s equator: Continue reading