Planetary Treats and Celestial Delights During Libra
For the Northern Hemisphere
September 22 - October 23, 2010

All times are local unless otherwise specified.

Look Up!

Planetary Treats
Extraordinary Jupiter
The Sunset Planets Are Sinking Away
Mercury's Horizon from MESSENGER

Saturn is Swallowed by the Sun!
Celestial Delights
Large Luna Sheds Light on Our Harvest
Plus ...

Sky Lights
Sky Calendars
Moon Dances 9/8-10/7
Moon Dances 10/7-11/5 Under Construction
Libra Navigation Page
The Night Sky ~ Home Page

Planetary Treats

Extraordinary Jupiter: + Two Red Spots – One Stripe + One Moon
Jupiter Is at Its Best! ~ Closest, Biggest, Brightest Until 2022!
Jupiter and Io | August 30, 2010, 5:38 UT


South is down.

Io lies to the upper right.

Jupiter is extraordinary for several reasons.

1. Every 13 months Jupiter lies opposite the Sun. During opposition the planet can be seen in the night sky at its closest, biggest and brightest from sunset to sunrise. In 2010 Jupiter’s exact opposition occurs September 21 at 5:00am PDT (12:00 UT). The change in Jupiter’s brightness and size is negligible for a couple of weeks before and after this date, so one has plenty of time to see the planet's BEST performance in years.

2. Jupiter is brighter and bigger in 2010 than it has been since 1963 or will be until 2022!

Next March, Jupiter reaches perihelion — the closest point to the Sun during its 12-year orbit — so it lies closer to Earth at this opposition than at a typical one. In fact, this is Jupiter's finest appearance in 47 years. Astronomy Magazine 09/10

Earth and Jupiter do not orbit the sun in perfect circles, they are not always the same distance apart when Earth passes by. On Sept. 20th, Jupiter will be as much as 75 million km closer than previous encounters and will not be this close again until 2022. NASA Science News 9/15/10

3. As seen in Alan Friedman’s photo above, Jupiter’s Great Red Spot pairs up with Red Spot Jr., also known as Oval BA, which birthed it. These Red Spots are HUGE swirling storms. GRS is almost twice the diameter of Earth, making GRS Jr. almost one Earth-diameter across. A telescope reveals their “perhaps too close for comfort” engagement now. Will Red Spot Jr. survive this intimacy?

4. Also seen or shall I say not seen in Alan Friedman’s photo above, is Jupiter’s missing stripe the SEB [South Equatorial Belt], which disappeared in May 2010! When will it reappear? Telescopic eyes of every size are keeping watch!

5. In addition, Jupiter at its best is in close proximity to Uranus at its best! With a telescope or binoculars one can see a special 2-for-one planetary treat!

6. In a dark country sky with binoculars, one can view Jupiter’s four Galilean Moons, its largest and brightest satellites. They appear starlike on either side of the planet. With a telescope you just might see one of these cast a shadow on the Jovian cloud tops.

7. There’s more! Amateur astronomers are reporting a surprising number of fireballs exploding in Jupiter’s atmosphere! Who will glimpse the next one?

Jupiter is extraordinary now! Look Up! Click Closest Encounter with Jupiter until 2022 to learn more from NASA.

Jupiter, having just reached opposition September 21, gives night sky travelers a BEST performance during Libra. Look Up! The King of Planets at magnitude -2.9 is the brightest point of light in the night sky after Venus sets. Jupiter's brilliance is easily seen in the southeast not long after sunset. The planet travels high above the southern horizon as the night progresses, setting in the west at 6:30am in the beginning of Libra and at 5:00am by its end.

Jupiter and Uranus remain near one another all through 2010. Their easterly (prograde) and westerly (retrograde) motion have brought them particularly close, in an exact conjunction, June 8 and September 18/19. Their final close encounter occurs January 4, 2011. Jupiter is retrograde 7/23-11/17. Uranus is retrograde 7/5-12/4.

During Libra, in the dim constellation of Pisces, both Jupiter and Uranus are at their closest, biggest and brightest for 2010. Uranus at magnitude 5.7 is now easily seen with binoculars and without an optical aid in a dark sky.

Uranus and Jupiter, in close proximity to each other, are also in close proximity to the Harvest Full Moon. 9/23 9pm Map Click Moon Dances for an additional map and meditative reflections.

Jupiter ~ The Fun To Watch Planet

Jupiter Observing Guide

Transit Times of Jupiter's Great Red Spot

Printable Great Red Spot Transit Table 2010-2011

Jupiter’s Moons
Sky & Telescope’s JavaScript utility helps
locate Jupiter’s four brightest satellites anytime
between January 1900–December 2100.
It also lists the satellite phenomena for the chosen day.
Jupiter's 4 Galilean Moons

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The Sunset Planets Are Sinking Away
Best Views in September

Image + Description
Image + Description

Venus and Mars are sinking in altitude toward the light of the setting Sun. Venus sets at the beginning of Libra at 8:00pm and Mars 30 minutes later. At the end of Libra, Venus sets with the Sun and Mars sets about 45 minutes after sunset. Venus is retrograde October 8-November 17 and in inferior conjunction October 28.

Venus, moving closer to Earth, is growing bigger and brighter; at magnitude -4.8 the planet pierces the twilit sky and briefly blazes low on the southwestern horizon. Mars, moving away from Earth, is gradually diminishing in size and brightness; at magnitude 1.5 it is challenging to see at dusk.

The planetary pair reside in the constellation Libra, near the star Zubenelgenubi (zoo-BEN-al-je-NEW-bee) . These 3 celestial bodies form a difficult to see shapeshifting triangle in the southwest just after sunset. Zubenelgenubi at magnitude 2.7 is quite a bit dimmer than the planets and may be impossible to see without the right optical aid. Best viewing opportunities occur in September if you have clear skies, an unobstructed horizon and right timing; binoculars are helpful in drawing these celestial bodies out of the twilight. October viewing is more challenging as the planets sink lower and set earlier. The further south your location the higher these planets appear.

Mark Your Calendar

September 23, Thursday, Venus is at its greatest brilliancy, setting an hour after the Sun. 9/23 7:30pm Map (The Zuben-star lies above and closest to Venus.)

October 1, Friday, Venus and Mars are in close proximity. 10/1 7:30pm Map by Sunday October 3 Venus and Mars are in exact conjunction.

October 9, Saturday, young Luna nestles between Venus and Mars. 10/9 Map (Mars lies to the left of the Zuben-star.) Click Moon Dances for meditative reflections.

Reflections ~ Venus and Mars

Venus and Mars are in exact conjunction three times within nine months: August 20/21, 2010, October 3, 2010, May 22, 2011.

Creative Potential. We are in a nine month passage that spans three conjunctions of Venus and Mars. ... Although Venus and Mars conjunct about every two years, this cycle of three conjunctions occurs about every 6 1/2 years. A potential for personal metamorphosis in establishing a more intimate and authentic relationship between your core self and the ingrained patterns of behavior of your conscious ego.

Venus' retrograde cycle [10/8-11/17] is integral to this dynamic. August through November, our attention is brought towards evaluating our relationships. Relationships with everyone (spouse, lover, friend, co-worker, boss, government) and everything (money, food, sexuality, possessions, emotional attachments, endless list here). Strategic engagement, negotiations, love and grace. Passion, life force, regeneration and healing. Deeper connection. Transformation. Jacqueline Lasahn / AstroFlash! 9/28/10

Venus Has Phases Like the Moon

You can see these phases and more in this Venus 2010 Animation. As Venus gets closer to Earth and bigger in disk, size its illuminated phase decreases; during Libra Venus wanes from a 27% - 2% illuminated Crescent. You can see this demonstrated in APOD's animation of the phases of Venus and in this montage.

Image the Phase & Apparent Disk Size of Venus

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APOD: Mercury's Horizon from MESSENGER - 2008 January 21


Pictured above is the limb of Mercury seen by MESSENGER upon approach, from about 1 1/2 Earth diameters away. Visible on the hot and barren planet are many craters, many appeared to be more shallow than similarly sized craters on the Moon. The comparatively high gravity of Mercury helps flatten tall structures like high crater walls. MESSENGER was able to take over 1,000 images of Mercury which will be beamed back to Earth for planetary geologists to study. The robotic MESSENGER spacecraft is scheduled to fly past Mercury twice more before firing its thrusters to enter orbit in 2011.

Source: APOD 2008 January 21 Check out the Current Astronomy Picture of the Day.

Mercury brightens with each new day, however it is now sinking back toward the sunrise horizon having achieved greatest elongation, and a best morning performance September 19.

In the beginning of Libra elusive Mercury rises at 5:45am. October 1 the planet lies 5 degrees above the eastern horizon and can be seen piercing the morning twilight 30 minutes before sunrise.

During the first week of October Mercury rapidly sinks out of sight. By October 16 the planet is in superior conjunction.

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is swallowed by sunlight during Libra and is in exact conjunction with our central luminary September 30. It is in the process of switching horizons now. The planet reappears in the morning sky shortly before dawn as Libra comes to an end, however easier viewing of sunrise Saturn occurs at the end of October.


The Planets
Is it a planet? ... What planet? When you look up at the night sky, how do you know you are looking at a planet? Learn what a plutoid is. Click here.

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Celestial Delights

The Harvest Moon is the name given to the Full Moon closest to the autumn equinox therefore, the Harvest Moon can occur in September or October. This year it occurs September 23 at 2:17am PDT (09:17 UT) just 6 hours after the September 22 equinox.

The Harvest Full Moon rises as the Sun is setting.

A Full Moon near the autumn equinox lies low in the south along an ecliptic that forms a very shallow angle to the horizon. This results in the Moon rising very quickly around the time of sunset ... also rising only 20 to 30 minutes between consecutive moonrises instead of the typical 50 minutes. Before electricity this additional light late into the evening allowed farmers more time to gather their harvest. For latitudes farther north the effect is more pronounced with less time between moonrises each night. It is not surprising that the name "Harvest Moon" originated in the northern European latitudes.

The Harvest Moon because of its closer angle to the horizon appears to loom extra large when it rises ... a well known illusion. In fact the Moon is actually closer to the Earth when it is highest in the sky!

Try this experiment as you watch the Moon rise from the horizon to overhead. Place your thumb and index finger a pencil width apart, at armís length. You should always be able to fit the Moon between your fingers no matter where it is! The Moon will always look bigger next to objects than when it is seen overhead in a dark sky.

Fun With The Harvest Moon Illusion
1-minute Star Gazer video

The Moon Illusion

Harvest Moon Images: Michael Myers

5 Harvest Moon Nights?!

Check it out September 21-25! Traditionally the Harvest Moon lasts more than one night. It includes the two almost Full Moons two nights before the official Full Moon and the two almost full Moons two nights after. Note: These 5 rising Moons tend to be more colorful because we see them through a thicker atmosphere than when they are overhead. The more polluted the atmosphere the more Luna blushes! A large, colorful Luna for 5 nights is definitely a treat to be harvested!

Every Year ...

Vega the fifth brightest star lies overhead during the first few weeks of autumn between 8:00pm and 9:00pm. Learn more about this "super bright star" in the fun and informative 5-minute Star Gazer Video.

BTW: Vega is the western star of the Summer Triangle and when Vega is above your head, our brightest star Sirius is below your feet! ;-) When Vega sets in the west between 4:30am and 3:30am during the first few weeks of autumn, Sirius is rises in the east.

In 2010 ...

For the first time in almost 20 years, northern autumn is beginning on the night of a full Moon. The coincidence sets the stage for a "Super Harvest Moon" and a must-see sky show to mark the change of seasons.

The action begins at sunset on Sept 22nd, the last day of northern summer. As the sun sinks in the west, bringing the season to a close, the full Harvest Moon will rise in the east, heralding the start of fall. The two sources of light will mix together to create a kind of 360-degree, summer-autumn twilight glow that is only seen on rare occasions. Full NASA Article

Jupiter and Uranus, in exact conjunction September 18/19, lie in close proximity to each other and to the Harvest Full Moon. 9/23 9pm Map Jupiter, a beacon of light, shines brighter and larger September 21 than it has anytime since October 1963! Jupiter is at its best now. In fact, a couple of weeks before or after the Harvest Full Moon its change in brightness and size are negligible. Uranus is also at its brightest and biggest for the year the same day Jupiter is, making Uranus a naked eye and binocular celestial object in dark skies rather than a telescopic one! 9/21 9pm Map Click Moon Dances for a map and meditative reflections. BTW: The night of the Harvest Full Moon, September 23, sunset Venus is at greatest brilliancy, magnitude -4.8. 9/23 7:30pm Map

You can help strengthen the light grid of planet Earth by participating in any of the following global meditations during this time.

International Day of Peace Vigil
Tuesday, September 21
Join us at in holding a meditative space
between 9:00pm and 9:15pm Pacific Time. Sound
The Great Invocation at both the beginning and
end of this time period. Participate during
this designated time or as you are inspired.

2010 Libra Global Meditation
Full Moon: Thursday, September 23 invites you to participate in the
Clarity of Purpose Global Meditation During Libra
We at are meditating the preceding night,
Wednesday, September 22 at 9:00pm PDT (04:00 UT 9/23).
Participate at this time or as you are inspired.

Global Meditations ~ Autumn Equinox


May your harvest be delicious and bountiful.
May it serve the greatest good!


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May your Night Sky traveling always be filled
with Celestial Delights and Treats!
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