2018, January 18: Jupiter and Mars

Bright Morning Star Jupiter and Mars shine from the eastern sky this morning.  Both planets are moving eastward compared to the starry background.

Jupiter is 4.3 degrees from the star Zubenelgenubi.  It passes Zubenelgenubi again on June 2, during its retrograde.

Mars is 5 degrees from Jupiter and marching toward a February 10 conjunction with the star Antares.

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

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2018, January 31: Chicago’s View of the Lunar Eclipse

Lunar Eclipse (image Credit: NASA)

A lunar eclipse occurs on the morning of January 31 during the second full moon of the month and the new year.  All the events of the lunar eclipse are visible from Asia, Australia, the Pacific Ocean Basin and western North America.

In the Chicago area, the moon sets in the western sky during the maximum phase.

Here are the events of the eclipse for Chicago area observers:

January 31, 4:51 a.m. CST — The moon is low in the western sky (altitude 23 degrees), just about two hours before it sets.  At this time, the moon enters the outer section of the lunar shadow — the penumbra.  For most observers not much change occurs in the moon’s brightness.

5:28 a.m. CST (Moon’s altitude, 16 degrees) — The moon appears lower in the western sky as the earth is rotating.  Morning twilight begins at this time.

5:48 a.m. CST (Moon’s altitude, 12 degrees) — The moon’s descent toward the horizon continues.  At this time the moon begins to move into the darker umbra and the partial eclipse begins.

6:01 a.m. CST (Moon’s altitude, 10 degrees) — The partial eclipse continues and the sky brightens.  Nautical twilight occurs at this time.  The sky is bright enough to distinguish the horizon — the line the separates the sky from the ground.

6:35 a.m. CST (Moon’s altitude, 4 degrees) — The moon’s descent continues as it is now only about 30 minutes before moonset.  Sometimes the moon and sun seem orange when they rise,  This is from the atmosphere erasing the yellow and blue light from  sunlight — atmospheric extinction. (This can also diminish the brightness of celestial objects.)  The moon appears orange during a lunar eclipse when red and orange light are bent through our atmosphere  While the moon is not in total eclipse, yet, the moon appears orange from the eclipse as well as the atmospheric extinction.  At this time Civil Twilight occurs; the sky is bright.  Street lights begin turning off.  It’s easy to distinguish details in terrestrial features.

6:51 a.m. CST (Moon’s altitude, 2 degrees) — The moon is very low in the western sky.  The moon is now completely inside the earth’s shadow — total eclipse.

7:04 a.m. CST — Sunrise

7:06 a.m. CST — Moonset

While all the stages of the eclipse are not visible from the Chicago area, the events leading up to the total eclipse are easily visible.

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

 

2018, January 6: Jupiter, Mars, and Moon

Bright Morning Star Jupiter appears in the southeast this morning. Tomorrow is conjunction morning with Mars. This morning the Red Planet is 0.3 degree to the right of Jupiter. Zubenelgenubi and Zubeneschamli form the starry background for this celestial dance.

Meanwhile, the waning gibbous moon is to the upper right of the planetary pair.

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

2018, January 5: Jupiter, Mars, and Moon

Bright Morning Star Jupiter shines from the southeast this morning with Mars close by.  Mars is 0.7 degrees from Jupiter and two days from its close conjunction the Giant Planet.

Jupiter is 2.3 degrees from Zubenelgenubi, in Libra.  Jupiter passed the star a week ago.  Jupiter passes it again in June during its retrograde.

Spica is 23 degrees to the upper right of Mars.  The Red Planet passed the star over a month ago.  Jupiter had a triple conjunction with Spica during its last apparition.

Meanwhile the 18-day-old moon shines high in the western sky.

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

2018, January 4: Jupiter, Mercury, and Mars

Bright morning star Jupiter shines from the southeast this morning. It is now well past Zubenelgenubi. This morning it is 2.3 degrees from the star.

Mars is heading toward its very close conjunction with Jupiter on January 7. This morning it is about one degree from the Giant Planet.

Mercury, just past its greatest elongation, appears near the horizon.  It is still a naked eye planet.  Find a clear horizon to see it.

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

2018: January 1: Jupiter, Mercury and Mars

On this New Year’s morning bright Morning Star Jupiter shines from the southeast with Mars nearby. Mars is 1.8 degrees from Jupiter and heading for a very close conjunction in six days.

Over a week ago, Jupiter passed Zubenelgenubi for the first conjunction of three (triple conjunction) during this appearance.  The second conjunction is June 2.

Mars is marching eastward compared to the starry background.  Just a month ago it passed Spica, now 20 degrees to Mars’ upper right.

Meanwhile, Mercury reaches is greatest elongation today low in the southeastern sky,  Mercury passes Saturn on January 13.  Find a clear horizon to see them together.

2017, December 27: The Moon

The nearly 10-day-old waxing gibbous moon shines high in the southeast this evening. Mare Imbrium, a large impact feature that is now a filled with cooled volcanic material, is nearly in sunlight. Imbrium is over 700 miles in diameter, easily visible without a telescope. Copernicus, lies south of Imbrium, now has its lunar morning as it is near the terminator, the division between daylight and nighttime.

Eratosthenes appears to the upper right of Copernicus at the western edge of the Apennine Mountains that form the rim of the Imbrium region.

Tycho is now in full sun farther to the south.  Its rays make it look like a huge lunar bug.  These bright lines are from material that splattered across the surface when a large meteorite crashed into the moon.  The greyish splash is easier observed in a few nights as the moon’s phase continues to wax.

Clavius is below Tycho.

To the lower left of Tycho and along the terminator where the shadows are longer from the rising sun, Longomontanus is visible.  Immediately north of Longomontanus is a cluster of three overlapping craters; the obvious one in the image is Wilhem.

All of these features are visible in the lunar image when it is magnified on the computer screen.

Lunar observing is an easy and inexpensive way to get started in astronomy.  The binoculars that are used for bird watching and sporting events can be aimed at the moon to view its features.  The moon is easily found in the sky and can form the basis of a regular observing habit as the changing phase either reveals or hides features:  craters, mountains, plains, and valleys.  Certainly this is a way to introduce a child to astronomy.  The investment in a good binocular is relatively inexpensive.  If the interests wanes, then the binocular has other functions.

If you’re interested in exploring the lunar surface further, a  good resource is Exploring the Moon Through Binoculars by Ernest Cherrington.  The book is now out-of-print, but might be found on the resale market inexpensively.  The author wrote another lunar observing book with a similar title, Exploring the Moon Through Binoculars and Small Telescopes.  This can be found inexpensively and in electronic versions.

Happy lunar observing.

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