2018, July: See Five Planets and Mars Opposition

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Look for 5 planets during the month.  From mid-northern latitudes, they are not visible simultaneously.  Look for Mercury about 30 minutes after sunset with binoculars, then wait for Mars to cross the southeastern horizon.  Four bright planets then span the sky from Mars to Venus.  Mars reaches its opposition later in the month.  The planet is closer than it’s been since 2003.

July opens with the waning gibbous moon in the south-southwest. Mars, now the second brightest planet, is 25° up in the south-southwest, 5.8° below the moon.  At the same time, Saturn is 10° up in the southwest.  With both planets near their oppositions, they appear in the southeastern sky during the evening and move westward during the night.  During the early evening, four bright planets are arched across the sky, with the trio of bright outer planets in retrograde.

One hour after sunset, brilliant Venus stands 14° up in the west.  Venus is 9° to the lower right of Regulus.  Watch Venus close in and pass Regulus during the first 9 days of the month.  At this hour, dimmer Mercury is 4° up in the west-northwest, setting nearly 90 minutes after sunset. Use binoculars to locate it. This speedy world approaches its greatest elongation during the first half of the month.

Meanwhile, bright Jupiter, 82° to the upper left of Venus, is 33° up in the south.  This giant planet is 2° west of Zubenelgenubi.  Saturn, just past its opposition and retrograding above the Teapot of Sagittarius, is 13° up in the southeast, 52° to the lower left of Jupiter.

Mars, racing toward its opposition later in the month, rises in the southeast 117 minutes after sunset.  The Red Planet, retrograding in Capricornus, appears 34° to the lower left of Saturn.  Start looking for the five naked eye planets during the early evening.  Look for Mercury during twilight, then wait for Mars to clear the southeast horizon. Here are the highlights for the first half of the month:

  • July 1: As the sky darkens, Venus is 9° to the lower right of Regulus.  Mars rises 117 minutes after sunset this evening.  The waning gibbous moon is 15° to the left of the planet.

  • July 2: The Venus-Mercury gap is 16.6°. Mercury sets 90 minutes after sunset, its maximum setting interval after sunset for this apparition. The Venus-Regulus gap is 8° this evening.  Watch Venus close the separation during the next several evenings: 07/03, 6.9°; 07/04, 5.7°; 07/05, 4.7°; 07/06, 3.6°; 07/07, 2.6°; 07/08, 1.5°.
  • July 4: The Venus-Mercury gap is 16.2°.  Mercury’s brightness is fading fast as it approaches its greatest elongation.  This evening its apparent magnitude is 0.2, but it is appearing in bright twilight.
  • July 6: The moon is at its Last Quarter phase at 2:51 a.m. CDT. Earth is at aphelion 94.5 million miles from the sun at 11:46 a.m. CDT.

    In early July, Venus passes the next signpost of the ecliptic, Regulus. This vivid blue star is less than one degree from Venus on July 9.

     

  • July 9: Venus is closest to Regulus this evening, 1 degree.  The planet appears to the upper right of the star.  Watch the gap widen during the next several evenings as Venus moves away and toward Spica. Venus has a conjunction with Regulus in about 13 months when they are near their solar conjunctions, both hiding in bright sunlight.  On October 3, 2020, Venus, 22° up in the morning sky at 90 minutes before sunrise, appears 33’ below the star.  On the previous morning, Venus is 36’ above Regulus.
  • July 12: Mercury is at its greatest elongation, 26.4° east of the sun at 12:29 a.m. CDT. Mercury is only 13° above the horizon at sunset. The Venus-Mercury gap is 16.4°.  Venus is now 3.4° past Regulus.  The gap grows about 1° each evening.  The moon is at its New phase, 9:48 p.m. CDT.
  • July 14: Not long after sunset look for the waxing crescent moon 2.1° to the left of Mercury with binoculars.  Mars passes 1.1° north of Psi Capricorni.
  • July 15: Venus passes 1° to the upper right of Rho Leonis.  The waxing crescent moon is between Venus and Regulus, 1.5° to the lower right of Venus and 5.1° to the upper left of Regulus.

At mid-month, Venus continues to dominate the evening sky with its brilliance.  At 65 minutes after sunset, Venus is 11° up in the west, setting about an hour later.  Venus is now 6.5° to the upper left of Regulus.  On July 15, the waxing crescent moon is 1.5° to the lower right of Venus. Mercury, now past greatest elongation and fading quickly into the sun’s glare, sets 71 minutes after sunset.  Use binoculars to catch it in bright twilight.  Jupiter, near Zubenelgenubi, is 30° up in the south-southwest.  Saturn, 19° up in the south-southeast, is 51° to the lower left of Jupiter.  Mars, the second brightest “star” and rising 65 minutes after sunset, is approaching its perihelic opposition. It is 18° up in the southwest 2 hours before sunrise.  Here are the highlights for the second half of the month:

July 16:  The waxing crescent moon is 11.9° to the upper left of Venus.  The Venus-Regulus gap is 7.7° and growing each day.

  • July 17: Jupiter’s retrograde ends 2° west of Zubenelgenubi.  Watch Jupiter move eastward toward the star during the next month. The waxing crescent moon is 24.8° to the upper left of Venus.  If you’ve not looked for all five naked eye planets, start looking for Mercury, 30 minutes after sunset with binoculars.
  • July 18: The waxing crescent moon is 9.2° to the upper right of Spica. During the next several nights, start looking for some Perseid meteors before the moon approaches its full phase, after midnight, and before morning twilight begins.
  • July 19: The moon is at its First Quarter phase, 2:52 p.m. CDT.  This evening the moon is 13.3° to the right of Jupiter.
  • July 20: Today is the 49th anniversary of Apollo 11’s historic moon landing. This date also marks the 42nd anniversary of the Viking 1 landing on Mars.  The waxing gibbous moon is 3.5° above Jupiter this evening.
  • July 22: The waxing gibbous moon is 8.4° above Antares.
  • July 24: This evening the waxing gibbous moon is 1.9° to the upper right of Saturn.

  • July 27: Mars (m=-2.8) is at opposition.  The Full Moon is 7° to the upper left of Mars.  The moon reaches its Full phase, 3:20 p.m. CDT.  Mercury (m=1.9) 32 minutes after sunset during early twilight.
  • July 31: Earth and Mars are closest (closest approach), 35.7 million miles away.

The month ends with four bright planets lined up across the early evening sky.  Brilliant Venus is 9° up in the west 70 minutes after sunset.  Mars is 7° up in the southeast.  Mars retrogrades until August 27.  It is 30° to the lower left of Saturn, 23° up in the south-southeast, above the Teapot of Sagittarius.  It retrogrades until September 6.  This ringed wonder is 49° to the left of Jupiter.  Jupiter is 26° up in the southwest, 1.5° to the right of Zubenelgenubi.  Watch this giant world narrow the gap to the star and pass it next month.  Jupiter is 50° to the left of Venus.

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2018, April 10: The Morning Planets and the Moon

Less than a month before its opposition, Jupiter gleams from the southwest this morning. The planet is now rising in the east-southeast at about 10 p.m. Jupiter is retrograding near the star Zubenelgenubi.

Mars and Saturn are farther east, beyond the star Antares. Saturn rises before 2 a.m. with Mars following closely behind. Saturn’s opposition is in June. Mars’ opposition is July, three oppositions in 79 days.

This morning Mars and Saturn are about 4 degrees apart.  Saturn begins to retrograde in a week (April 17).

The waning crescent moon (24 days old) is low in the east-southeast this morning, outside the frame of the planets.

The articles that follow provide details about the planets visible without optical assistance (binoculars or telescope):

2018, April: Watch Venus Move Through Taurus

During late April, brilliant Venus moves through the stellar background of Taurus with its two bright star clusters:  Pleiades and Hyades.

On April 24, Venus is closest to Alcyone, the brightest star in the Pleiades cluster.  They are 3.5 degrees apart.

The Pleiades is a compact grouping of bright bluish stars known to school children as “The Seven Sisters.”  The cluster resembles a tiny dipper.  To the unaided eye, 6 or 7 stars are visible.  A dozen or so through binoculars.  A few hundred through telescopes.  The Hyades are nearby.  This group resembles a check mark, a letter “V” when Aldebaran is included, although it is not part of the cluster.

Astronomical theory describes that stars are formed in bunches from a stellar, gaseous nebula.  Over time the mutual gravitation pull of the stars within the cluster is not strong enough to keep the group together.  The Hyades and Pleaides are close enough (within 400 light years) that they can be seen without a telescope.  Many star clusters are just beyond the perception of our eyes.

The star cluster pair is best-observed through binoculars,  Start observing Venus’ movement through the region nightly at mid-month.  On April 18, the crescent moon appears among the Hyades.

Watch the events unfold during the spring evenings.

For more about Venus and the bright evening planets, see these articles:

2018: May 8, Jupiter at Opposition

 

In mid-northern latitudes, May is one of the best months for sky watching.  While the sun continues to set later throughout the month amid warming temperatures, cool, clearing breezes blow from the northwest revealing a transparent sky.  Enjoy the season.

Jupiter is the first of the three bright outer planets to reach opposition in a span of 79 days.

For more about Jupiter and the bright evening planets, see these articles:

Bright Jupiter enters the early evening sky at its opposition on May 8.  It is 3.2° from Zubenelgenubi.  Jupiter is retrograding and passes the star on June 3.  After the planet resumes direct motion, Jupiter passes the star again on August 15.   Jupiter ends the month, just 1° from Zubenelgenubi.  On the chart above, Jupiter gleams in the southeastern sky at 10:30 p.m. CDT on opposition night.

May opens with brilliant Jupiter shining in the west after sunset.

 

The waxing gibbous moon moon (16.1 days old) is 18° to the left of Jupiter.  The planet rises at 8:17 p.m. CDT (in Chicago), 18 minutes after sunset.

As the month ends, the moon passes into Jupiter’s field again.  The chart above shows the view in the south at 10:50 p.m. CDT.  Here are the highlights:

  • May 25: The waxing gibbous moon (10.7 days old) is 6.3°  above the star Spica.
  • May 26:  The waxing gibbous moon (11.6 days old) appears farther east this evening.  It is 9.3° to the right of Jupiter.
  • May 27:  The nearly full moon (12.6 days old), yet still waxing gibbous is 5.1°  to the left of Jupiter.
  • May 28:  The full moon is 17.5°  to the left of Jupiter and 10.9°  above Antares.

As the month closes Jupiter shines brightly in the southeast at sunset.

2018, Summer: Evening Planet Parade: Five Bright Planets Visible During One Evening

For about a month near the summer solstice, five planets are visible during the early evening, but they are not easily visible simultaneously from mid-northern latitudes.  As the sky darkens a parade of planets extends across the sky from brilliant Venus in the west to Mars in the southeast. The “X” factor of seeing 5 planets simultaneously is Mercury. It reaches its greatest elongation on July 12, although Mercury is visible throughout its apparition.

For more southerly locations in the United States and farther southern latitudes, see this article:  2018:  Five Planets Visible at Once

Here’s how to look for the five planets:

June 16, 2018:  Start looking for Mercury early it its apparition, although the rising time for Mars is much later.  From an observing location with a clear horizon, locate the speedy planet Mercury 30 minutes after sunset. Mercury sets 63 minutes after sunset, 15 minutes before Nautical Twilight (sun’s altitude is -12°).  Mars rises in a dark sky nearly 3 hours after sunset.  At 30 minutes after sunset on this evening, Venus is 25° to Mercury’s upper left.  The waxing crescent moon (3.3 days old) is 7.9° beyond Venus.

July 2:  Again with binoculars first locate Mercury 10° up in the west-northwest 30 minutes after sunset with brilliant Venus 16.6° to Mercury’s upper left.  Regulus is 8.1° beyond Venus.  Mars touches the east-southeast horizon 25 minutes after Mercury sets and 15 minutes before the end of twilight.

July 12: At sunset, Mercury is 13° up in the west-northwest.  Thirty minutes later, it has an altitude of only 8.5° with brilliant Venus 16.4° to its upper left.  Venus is 3.4° beyond Regulus.  Mercury sets 78 minutes after sunset and Mars touches the southeast horizon at the same time.  Locate Mercury, then wait until Mars clears the east-southeast horizon.

July 17: The best evenings for seeing all five planets are around this date, but you’ll need optical assistance.  Thirty minutes after sunset, dimmer Mercury is 5.1° above the horizon.  Mercury is dimmer as the apparition continues so optical aid is needed to first locate it. Regulus is 9.5° to the upper left of Mercury with Venus 8.5° beyond the star.  Mars rises six minutes before Mercury sets, although both are low in the sky.    Twilight lingers for over 2 hours at this time of the year at mid-northern latitudes.

On July 17, 2.5 hours after sunset and after Mercury sets, the planet parade arches across the southern sky.  Brilliant Venus sparkles 5° up in the west and Mars is 5° up in the southeast.  Saturn is 32.8° to the upper right of Mars, above the Teapot of Sagittarius.  Jupiter is 50.8° to the west of Saturn and 1.8° to the west of Zubenelgenubi.  The moon (5.0 days old) is nearly between Venus and Jupiter.

Another opportunity to see five planets simultaneously, from mid-northern latitudes, occurs in the morning near the time of the summer solstice in 2020.  While these groupings are infrequent, they provide magnificent displays of the solar system’s beauty.

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2018, March 21: #Venus, Mercury and Moon, The Early Show, #Mercury Slips Into Bright Twilight

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Click through this short slide show to see Venus, Mercury and the Moon this evening.

Brilliant Venus shines from the western sky this evening.  Now setting nearly 90 minutes after sunset, this evening planet appears higher each evening at the same time.

Dimmer Mercury is 4.5 degrees to the right of Venus.  Binoculars help finding its location.  It is rapidly diving into bright twilight and fading in brightness.  On April 1, it passes between Earth and Sun, and moves into the morning sky,

The 4.5-day old crescent moon appears 38 degrees above Venus this evening.  Watch it appear higher in the sky, more distant from Venus, and with a growing phase as it continues through its celestial path.

The articles that follow provide details about the planets visible without optical assistance (binoculars or telescope):

2018, March 18: Venus and Mercury, The Early Show, The Moon Joins the Party

A thin crescent moon, nearly 1.5 days old, joins brilliant Venus and Mercury this evening. Mercury is partly hidden by the clouds.

Venus is entering the sky after its superior conjunction. Mercury is a few days past its greatest separation from the sun and heading toward its solar inferior conjunction in early April.

Tomorrow evening Mercury is lower in the sky and the waxing crescent moon is about 13 degrees to the upper left of Venus.

The articles that follow provide details about the planets visible without optical assistance (binoculars or telescope):