Tag Archives: Mars

Venus and Jupiter (and the Pleiades and Mars) Tonight, April 5, 2012

Clear skies prevailed this evening in the Chicago area with Venus and Jupiter in the west after sunset as shown in the 30-second exposure above made at 8:15 p.m. CDT. The Pleiades star cluster now appears below Venus as the planet has moved past the cluster. Aldebaran, the brightest star in Taurus, appears nearby.

Meanwhile back in the southeast, Mars shines brightly in front of the stars of Leo. Regulus and Denebola, the brightest stars in Leo, are easily visible. This 30-second image was made at 8:15 p.m. CDT.

April 2012 Skywatching

Image Credit

Moon Phases

New — 21
First — 29
Full — 6
Last  — 13

April provides lengthening daylight and a continued dazzling display of Venus in the western sky after sunset.  During the month daylight increases by an hour to nearly 14 daylight hours by month’s end in the Chicago area.

Mercury is a morning object throughout the month. From the northern mid-latitudes it lies low in the eastern sky during predawn hours. The moon is nearby on the mornings of April 18 and 19.  On the first date, locate the moon, then use binoculars to find Mercury.

This chart shows the evening appearance of Venus for 2011-2012. The chart shows difference between the time the sun sets and Venus sets. Chart compiled from US Naval Observatory data.

Throughout the month, Venus continues its brilliant display in the western sky.  The chart above shows the length of time between sunset and Venus setting.  During the first several days of the month, Venus sets nearly seven hours after sunset.  From that point until mid-May, when it disappears into the sun’s glare, it rapidly sets earlier each night.  Venus is quickly catching Earth and will pass between Earth and the sun in early June.    Venus reaches it greatest brilliance on April 30.   At this time, Venus is 12 times brighter than Jupiter.

A planet’s brightness depends on its distance, its reflectivity and its phase.  (Planets display phases similar to the moon.  Mercury and Venus display crescent phases, but the other planets do not.)  The chart above shows the inner solar system and the proximity of Venus and Earth when Venus is at its greatest brilliance on April 30.  In this view, the planets move counterclockwise.

Early in the month, Venus appears to pass the Pleaides star cluster.  In a dark sky the Pleiades are visible to the unaided eye.  For those readers who live in areas with many lights, use binoculars to locate the planet and the star cluster on the evenings of April 2-4.  The grouping can be photographed.  Use the manual setting on a camera with the aperture setting the widest setting (lowest number).  On a tripod, make a 30 second exposure.  Venus and the stars will appear on the processed image.

The moon returns to the evening sky late in the month as Venus is at its greatest brilliancy. On the evening of April 24, the moon appears between Venus and Aldebaran, the brightest star in Taurus.

Mars is high in the eastern sky at sunset. The chart above shows Mars, the star Regulus, and the moon at 8:45 p.m. CDT. As our planet rotates during the night, Mars appears farther to the west during the night as it sets in the west during predawn hours.

During the month Jupiter rapidly disappears into the sun’s glare. The chart above shows Jupiter at 8:10 p.m. CDT on April 15. Notice the great separation between Venus and Jupiter on this date. Jupiter goes behind the sun (conjunction) on May 13 and reappears in the morning sky later in June.

Saturn reaches opposition on April 15, entering the sky at sunset. (At opposition the sun and planet are on opposite sides of the sky as the earth passes between the planet and the sun.) When a planet is at opposition, it rises at sunset, appears in the south at midnight, and sets in the west at sunrise. The chart above shows Saturn, the star Spica, and the moon on April 6, 2012 at 10 p.m. CDT.

Even though Saturn is larger than Venus and Earth, its great distance diminishes its brightness.  Venus is nearly 100 times brighter than Saturn during the month of April.

This chart shows the positions of the planets visible without a telescope or binocular on April 15, 2012.   (Click the chart to see a larger image.)  Notice that Earth is between the sun and Saturn (opposition). Venus is about to move between the Earth and Sun.

Venus and Jupiter (and Mars) Tonight, March 21, 2012

This evening Venus and Jupiter shine brightly through the haze in the western sky. The Pleiades star cluster appears above Venus. Aldebaran, the brightest star in Taurus, also appears in this view. This digital image was made with a 30-second time exposure.

Looking back to the east at the same time, Mars is well up in the eastern sky among the stars of Leo. Regulus and Denebola, stars in Leo, appear in this view. This digital image was made with a 30-second time exposure.

Venus and Jupiter (and Mars) Tonight, March 14, 2012

Looking west this evening at 7:45 p.m. CDT, Jupiter is slightly lower than Venus compared to last night. The separation will continue for several more weeks.  (This image was made with a two second exposure.) After seeing the dazzling display of brilliant planets in the west, Mars is in the east. 

This 30 second time exposure shows Mars through nearby trees.  The light pollution in the Chicago area is so bright that this view seems to make the scene appear like daytime.  To read more about the planets this month, see our monthly update.

Sky Watching, March 2012

Moon Phases:

Full Moon — 3/8
Last Quarter — 3/14
New Moon — 3/22
First Quarter — 3/30

Daylight Saving Time begins for most states in the U.S. on March 11 at 2 a.m. local time.  Advance clocks 1 hour.

The Vernal Equinox occurs on March 20 at 12:14 a.m. CDT, signalling the beginning of Spring.  Daylight increases for three months until late June.  At this time, the sun appears directly above the equator, meaning that individuals living at the equator have the sun appear directly overhead.  The sun does not appear directly overhead from the Chicago area.

The month opens with the spectacular Venus-Jupiter gathering in the western sky, just after sunset.  With binoculars and a clear horizon, locate Mercury low in the sky early in the month. 

By mid-month, Jupiter and Venus appear close together.  While millions of miles apart, the two planets appear about 3 degrees (six full moons) apart.  The chart above shows the pair on March 12, one of the nights they appear closest.  Notice the view is one hour later as daylight saving time (advance your clock one hour) on March 11.

The animation above shows Venus and Jupiter each night during March 2012 in the early evening sky.  Watch to two planets appear to converge then separate.


After the closest pairing of Jupiter and Venus, the moon appears in the western sky with them in late March.  Here’s what to look for at approximately 8:15 CDT in Chicago:

March 24:  The waxing crescent moon appears below Jupiter and Venus, near the western horizon.
March 25: Jupiter and the moon are paired nicely, with the moon appearing slightly higher and to the right of Jupiter
March 26:  Tonight, Venus and the moon are nicely paired with both objects appearing about the same height above the western horizon.  This is the night to catch a classic photographic view of the moon and Venus together.
March 27:  The moon stands above Venus and Jupiter as the planetary pair continues to separate.

At the same time that the brilliant group gleams in the western sky, Mars lies low in the eastern sky.  It is the brightest starlike object in this part of the sky, but it dramatically under shines the bright duo in the west.  Mars appears slightly red-orange and its color can be distinguished with binoculars.  On March 3,Earth passes between the sun and Mars — an opposition.  At this time, Mars is about 60 million miles away.  An opposition for Mars occurs about every 25 months.  Because Mars’ orbit is moderately elliptical, this opposition occurs when Mars is farthest from the sun (aphelion), it is not as close or as bright as several previous oppositions.

The waxing gibbous moon appears near Mars on March 6 and March 7.

A few days  later, the Moon appears near Saturn and Spica.  Saturn rises just around midnight in the southeastern sky.  The chart above shows the planet-star pair with the moon for March 10 and March 11.  The constellation Corvus is nearby.

The chart above shows the planets at mid_March 2012. Notice that an imaginary line extended from Earth to Venus goes to Jupiter. That is why the two planets appear close together in our sky, but they are widely separated in space. Additionally notice that our planet is between Mars and the sun — they are on opposite sides of Earth.

February 2012 Skywatching

 

Orion, winter’s flagship constellation, is in the southern skies during the evening hours of February.  The pattern is easily found by locating three stars of nearly equal brightness and equal spacing about halfway up in the southern skies.  This represents Orion’s belt.   The reddish star Betelgeuse can be found above the belt stars and bluish Rigel below.  The two stars are display contrasts of star color.  Compare the two stars’ colors through binoculars.  The colors indicate temperatures.  Rigel is much hotter than Betelgeuse.  In addition, Betelgeuse is very large.  The sun and  inner solar system could fit inside an empty Betelgeuse.
 
While you have your binoculars, look for the Great Orion Nebula among the stars of Orion’s sword.  The nebula has a distinct, greenish glow.  The fantastic colors in photographs do not appear to the human eye.   Film and electronic photography have the ability to collect light over long time periods where the colors are revealed.
 
During February, we experience about 1 hour of additional sunlight in the Chicago area.  By month’s end the sun sets around 5:40 p.m. and rises around 6:30 a.m.  This year we add a day to the calendar to account for the earth’s revolution around the sun.  To keep our calendar matched with the seasons, we add a day.  If we do not reset the calendar every four years, eventually the coldest days of the year would occur when the calendar reads July.  See the US Naval Observatory for a longer description.
 
Moon Phases
Full — February 7
Last — February 14
New — February 21
First — February 29

As the sky darkens during early February 2012,  two bright planets dominate  the sky.  Venus shines brightly in the western sky, standing above the horizon and Jupiter gleams from the southern skies.  Early in the month, the moon is east of the planets and outside the view shown above.

At night only the moon outshines Venus in brilliance. In turn Venus easily outshines Jupiter, appearing about 6 times brighter than the solar system’s largest planet.  Venus is our planet’s nearest neighbor and its clouds are highly reflective as they return over 70% of the sunlight that reaches them.

Jupiter takes nearly 12 years to orbit the sun once.  As we revolve around the sun each year, stars appear in the morning sky just before sunrise.  Each day they rise earlier than the previous day.  Each week they appear farther toward the west at the same time.  This westward movement of the stars reflects our revolution to the east in our planet’s orbit.  Because Jupiter revolves so slowly, its location in the sky reflects the westward movement of the stars in general, with some differences.

Several weeks after appearing in the morning sky, the stars and Jupiter appear in the east around sunset.  Looking each week at the same time, we notice that the stars are higher in the east.  Several weeks later, the stars are in the south at sunset, continuing to appear farther west at the same time.  As Earth revolves, the stars appear in the west as the sky darkens, and then reappear in the eastern sky just before sunrise, repeating this annual cycle. 

As this westward match continues, watch Jupiter during February approach Venus.  Late in the month, the moon passes in the region of Venus and Jupiter as indicated on the chart above, February 24-27.

As an extra, with binoculars or at low power in small telescope, look for the planet Uranus near Venus on February 9.  With optical aid, Uranus will display a bluish-green disk while the stars will appear as points.  The chart above shows a magnified view of the area around Venus.  Uranus is just at the limit of human eyesight in a dark sky, so some magnification through a binocular or small telescope will be needed.

With binoculars on February 22, look for Mercury and the moon low in the west at 5:45 p.m.  Locate a view spotting with a good view of the natural horizon, away from houses and trees.

Mars shines brightly from the eastern evening skies during the month near Denebola, the star that represents Leo’s tail, although it is one-third the brightness of Jupiter and only about one-tenth the brightness of Venus.  During the month Mars will increase in brightness as our planet approaches and passes the Red Planet.  On the evening of February 9, the moon appears nearby.

A few nights later, the Moon appears near the star Spica and Saturn with constellation Corvus nearby.  The chart above shows the view at 1 a.m.  As the night progresses, the moon and other objects will appear to rise, appearing in the southern skies around sunrise.

The chart above shows the positions of the planets in the solar system at mid-month.  With the planets moving in a counter clockwise motion, Earth is catching up and readying to pass Mars.  Venus moves faster than Earth and it is slowly catching up with our planet.

Take a look at the sky this month!

January 2012 Sky Watching

Taurus the Bull is visible high in southern skies during January

January opens with a sky full of stars and planets in the evening sky.  Taurus the Bull appears high in the southern skies during January’s evening hours.  Two bright star clusters, known as the Hyades and the Pleiades, help construct the constellation.  The “V” shaped cluster forms the bull’s head and face, although the bright reddish star Aldebaran that forms the bull’s eye is not part of the cluster.  Aldebaran is one of the largest stars in our part of the galaxy.  If placed in our solar system, it would extend beyond the orbit of Mars.  The Pleiades ride on the bull’s back.  The Taurus region of the sky is best explored with the low power of binoculars.  The stars in the clusters are so widely spread that they are best viewed with at low power.

Moon Phases

First Quarter:          January 1 & January 31
Full Moon:                January 9
Last Quarter:           January 16
New Moon                January 23

Our planet, Earth, reaches perihelion — its closest point to the sun — on January 4 at 6 p.m. CST.  At this time we are 91,401,967 miles from the sun. 
 
Along with the bright stars, Venus and Jupiter shine brightly in the clear January skies. 
 
Venus can be seen low in the western sky throughout the month.  As the planet slowly catches up to our planet, Earth, in its orbit, it rises higher in the sky and gets brighter each evening.  The moon is nearby on January 25 and 26.  Only two other objects are regularly brighter than Venus:  the sun and the moon.  It can be easily mistaken for the bright lights on an airplane.
 
The moon passes Jupiter early in January 2012.The moon makes a return pass by Jupiter later in the month.
 
The moon passes Jupiter a second time in late January 2012.
 
Jupiter shines brightly, although not at bright as Venus, from the southern skies during the early evening.  Venus shines about 4 times brighter than Jupiter.  The moon passes Jupiter twice this month as the charts above show, first early in the month (January 2) and then again on January 29 and 30.
 
Morning Sky
 
 

Mercury opens 2012 low in the southeastern sky before dawn.  The planet is difficult to locate without a good horizon and binoculars.  Antares and Sabik are nearby.  Mercury disappears into the bright sun’s glare during the second week of the month and is invisible until it appears in the evening sky in late February.

Mars rises in the eastern sky around midnight this month, appearing near Denebola — Leo’s tail.  On January 13, its identification is easier when the moon is nearby.

A few days later, the moon is near Saturn.  At 5:30 a.m. on January 16, the moon appears near the planet and Spica.

On the morning of January 19, the moon makes a nice configuration with Antares and the stars of Scorpius around 5:30 a.m.

The chart above shows the positions of the visible planets at mid January 2012.  Mercury is headed for superior conjunction (behind the sun) and Mars for opposition (Earth is between Mars and the sun.)  Saturn and Jupiter are nearly on opposite sides of the their planetary orbits from each other.

Skywatching, December 2011


Image Credit

The Sun reaches its southern-most point in its yearly travels at 11:30 p.m. CST on December 21, signalling the beginning of winter in the northern hemisphere and the beginning of summer for southern latitudes.  This is the Winter (December) Solstice.

The Moon  is in total lunar eclipse on December 10, but the best parts of the eclipse are not visible from the Chicago area.  The eclipse begins at 5:33 a.m. CST, when the moon enters Earth’s penumbra.  The lunar darkening is largely unnoticed by most observers.  At 6:45 a.m. CST, the moon enters the darker shadow where the partial eclipse begins.  The moon is very low in the western sky, setting only 25 minutes later.  The sky is brightening as the moon sets with sunrise.  Farther west in the U.S. more of the eclipse is visible, although the full eclipse is visible from the Pacific, Australia and Asia.

A lunar eclipse occurs when the moon crosses into the earth’s shadow.  The moon’s orbit is tilted slightly compared to the earth’s orbit.  The moon does not cross into the shadow each month.  The next total lunar eclipse visible from the Chicago region is April 15, 2014.  Parts of a partial lunar eclispse are visible  June 4, 2012.

Moon Phases

First Quarter — 12/2
Full Moon — 12/10
Last Quarter — 12/18
New Moon — 12/24

 

Mercury moves rapidly past Earth (inferior conjunction) on December 4 and into the morning sky.  During the last half of the month it makes an appearance low in the eastern sky somewhat near the star Antares.  The chart above shows Mercury, the moon, and Antares at 6:30 a.m. on December 22.  Find a place with a clear view of the horizon to see the widely spaced trio.  Binoculars will help locate Mercury and Antares.

Venus is the bright “star” in the southwest, just after sunset.  Its brilliance can be easily confused for an airplane.  Late in the month, the moon appears near Venus as displayed on the chart above.

Mars is a reddish “star” that rises around 10:30 p.m. during this month.  It is near the stars of Leo (Denebola and Regulus).  On December 16 and 17, the moon is nearby and is identified on the chart above in the southern skies at 5 a.m.

As the sky darkens each evening with Venus in the west, bright Jupiter is in the eastern sky.  Jupiter rises during the daytime and is high in the southeast by 8 p.m.  The chart above shows Jupiter and the moon for December 5 and 6.  Jupiter appears to move westward as  our planet rotates, setting in the western sky around 3 a.m.

Saturn rises during the predawn hours and is visible low in the southeast around 5 a.m.  It is near the star Spica.  The constellation Corvus is nearby.  One December 19 and 20, the moon helps with the identification of Saturn and Spica.

Viewing the morning sky, three planets (Mercury, Saturn, and Mars) line up across the sky in late December.  At 6:40 a.m., Mercury is low in the east, Saturn is in the south, and Mars is higher in the southwest.  The chart above shows the three planets at this time.

Viewing the solar system from above, the trio described above are on the same side of the sun as Earth, appearing in the morning sky.  Venus and Jupiter are in the other side appearing in the evening sky.

As the daylight continues to shrink, the bright winter sky appears earlier and stays longer, giving observers an opportunity for some skywatching.

November Sky Watching

The immense Andromeda galaxy, also known as Messier 31 or simply M31, is captured in full in this new image from NASA’s Wide-field Infrared Survey Explorer, or WISE. The mosaic covers an area equivalent to more than 100 full moons, or five degrees across the sky. WISE used all four of its infrared detectors to capture this picture (3.4- and 4.6-micron light is colored blue; 12-micron light is green; and 22-micron light is red). Blue highlights mature stars, while yellow and red show dust heated by newborn, massive stars.  More details.

NASA Photo

November evening skies are a transition between the bright stars that dominate summer and winter skies.  Our summer view of the Milky Way is shifted towards the west and the winter section appears in the eastern sky later in the night.  This permits views of celestial wonders beyond the bounds of our home galaxy.  The magnificent Andromeda Galaxy,also known as M31, is nearly overhead throughout the month.  Binoculars will reveal a fuzzy patch of light.  The photo above shows a satellite view of the galaxy revealing stars of varying ages.

Moon Phases

First Quarter November 2
Full November 10
Last Quarter November 18
New November 25

As for the planets visible this month from the Chicago area and across the globe at northern mid-latitudes,  Mercury and Venus are low in the southwest during evening twilight.  The accompanying video shows their positions each evening for the month.  The video repeats twice.  To locate this pair, find a location with a clear horizon.  With binoculars locate them in the southwest sky.  Mercury moves very quickly.  It is visible near Venus for most of the month then disappears into the sun’s glare.

 At month’s end Venus appears near a crescent moon on November 26.

Daylight Saving Time ends 2 a.m. Central Time for the time zone on November 6.  During the month we lose another hour of daylight as the sun appears farther to the south.

A solar eclipse occurs on November 25, but it is visible from the southern hemisphere (South Africa, Antarctica, Tasmania, and New Zealand).

Mars is a morning planet that is visible high in the southeast before sunrise.

Early in the month, Mars appears to pass Regulus.  Watch Mars’ rapid eastward motion compared to Regulus by looking each clear morning.  They appear closest on the morning of November 10.

 About a week later, the moon appears near Mars and Regulus.  In the diagrams above, notice how far Mars has moved past Regulus, since their closest appearance.

Jupiter appears in the east at sunset.  It is brighter than all celestial objects in its vicinity, except when the moon appears nearby on the evenings of November 8 and 9.  The planet is in the south around midnight and in the west during morning twilight.

Saturn rises in the east before sunrise, appearing near Spica.  The moon is nearby on November 22.

The planets’ positions in their orbits are shown for mid-November 2011.

Share your observations in the comments section.

Moon and Planets, October 2011

Look for the Big Dipper low in the northwest sky during early evenings in early autumn

As the weather changes into the cooler evenings of autumn, the stars slowly transition toward the bright winter stars.  One familiar group, known as the Big Dipper in North America, lies low in the northwestern sky during the early evening hours of October.  More, formally known as the Great Bear (Ursa Major), the stars can be found in the northern sky throughout the year.  In autumn they start the evening low in the northern sky; they are likely blocked by the trees or the neighbor’s house.

An interesting pair of stars, Mizar and Alcor, is at the bend of the dipper’s handle.  Mizar is the brighter star with dimmer Alcor nearby.  If you cannot see the close pair, use binocular.  While not physically connected in a binary star system, their close proximity makes them appear together.  Mizar is about 100 light years away with Alcor perhaps another light year away from its brighter neighbor.

Moon Phases

First Quarter   3
Full 11
Last Quarter 19
New

26

 

The positions of the visible planets on October 15, 2011

 This chart shows the positions for the visible planets as seen from north of the solar system.  Notice that Earth is between Jupiter and the sun.  Venus, Mercury, and Saturn appear near the sun.  Earth is slowly moving up to catch Mars.

Look in the west for Venus, Mercury and the moon just after sunset on October 28.

Always difficult to locate, Mercury appears near Venus in late October.  As the sky darkens on October 28, look for the moon and the reddish star Antares.  Look farther to the right of the moon for bright Venus and below it for Mercury.  You’ll need a good horizon.  Binoculars will help locate Mercury.

 
Venus is slowly emerging from behind the sun.  Early in October, Venus sets about 50 minutes after the sun.  Venus sets later than the sun throughout the month, ending the month setting about 90 minutes behind the sun.  The chart from last month’s night sky description shows the difference of times between sunset and Venus set.
 
The moon, Mars, and Regulus appear in the morning sky late in the month.

Mars is a morning star rising after 1 a.m. throughout the month.  Early in the month, it appears near the Beehive Cluster.  (See the separate article about this event.)  The moon serves as a good guide to Mars on October 21 and 22 as displayed in the chart above.  The star Regulus serves as a marker of the sun’s annual path and the plane of the solar system.  Look for Mars each morning and note how its orbital motion is carrying it closer to Regulus.  Of course, the two are not close;  Regulus is much farther away than Mars.  Mars will appear to pass Regulus next month.

Jupiter and the moon appear near each other at mid-month.
 Jupiter is the “bright star” in the eastern sky during the early evening hours.  Jupiter is at opposition and closest to Earth on October 29.  At this time the sun and Jupiter are on opposite sides of our planet.  Jupiter will rise in the east at sunset, be south around midnight and set in the west around sunrise.  It’ll be in the sky all night.  On October 12 and 13, the moon makes a nice grouping with Jupiter and the star Hamal.
Saturn appears near Spica at month’s end in the east before sunrise.
 Saturn is not visible for most of the month.  It is at conjunction on October 13.  At this time, the sun is directly between Saturn and our planet, so that Saturn is in the sky during the daytime.  Look at the planet orbit diagram above to see Saturn’s location compared to our planet.  By the end of the month, Saturn rises into the eastern sky, just before sunrise.  On Halloween, Saturn appears near Spica.  As for most observations that occur during twilight, use binoculars to see the pair.
 
Please share your observations in the comments section or ask any questions that can be answered in future articles.