Viewing all 5 Visible Planets in one night

As the nights grow longer and the skies darker, we have the chance for the next few weeks to see all five planets visible to the naked eye in a single night. Of course, there are seven planets in our Solar System (not including Earth), but two (Uranus and Neptune) are just too faint to see without optical aid. However, the rest (Mercury, Venus, Mars, Jupiter and Saturn) are spread around the entire sky, adding a lot of brightness to our already-shiny Autumn and Winter skies. This article in the science blog EarthSky is an excellent guide to help you find each planet. Of course, to find Jupiter and Venus you need little guidance because they are so bright, but Mercury, Saturn and Mars will be easier to find with some assistance from a sky map.

And if you are ready to look deeper and see all 7 in one night, here is a chart to guide you to Uranus and Neptune. They are both just west of Jupiter, in the constellations Pisces and Aquarius.

Image courtesy NASA.

Big Astronomy Events in 2011 and 2012

Much of the time, I enjoy astronomy as a day-to-day hobby, taking in the sky often and enjoying the slowly changing view of the heavens. Sometimes, however, big events come along and obligate the observer to be present at a specific moment in time -- and also have the good luck of clear skies. We have a three such events in the coming year, and the San Francisco Bay Area is a good base from which to see these events.

1. Total Lunar Eclipse, December 10th, 2011.

This Lunar Eclipse will peak on Saturday morning, December 10th, just before sunrise here in San Francisco, meaning that if the skies are clear, the best view will be at the coast, where the Full Moon will be entering Total Eclipse just as it is setting over the Pacific. This will be impressive!

2. Annular Eclipse of the Sun, May 20th, 2012.

An Annular Eclipse, also called a "Ring of Fire" eclipse, happens when the Moon's disk fits "inside" the disk of the Sun, creating a ring of sunlight in the sky. It's not the same as a Total Solar Eclipse, but still a beautiful natural phenomena, one worth a trip to Northern California to see. The viewing path can be seen on the map in this link, and will pass near Redding and Mt. Shasta in Northern California. I'll be organizing a road trip with the San Francisco Amateur Astronomers (SFAA) to see this spectacle.

3. Transit of Venus, June 6, 2012.

A transit of a planet in front of the Sun is a rare and unusual event. This is one of a pair of transits of Venus, the first of which occurred in 2004, paired with this one in 2012. Then we have a 100-year gap until the next pair of transits of Venus. It will be a daytime event, of course, because we are going to see the tiny disk of Venus cross directly over the Sun's disk.

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I'll write about each of these events as the time draws nearer, so for now the main thing is to mark your calendar and do a bit of background reading by following the links in this blog post.

Image courtesy of NASA.

The Moon amid planets and star clusters

The morning sky this week will be rich with easy-to-spot celestial objects in the hour before sunrise. Find a good view toward the eastern horizon and use binoculars to enhance the view of Venus, Mars, the waning crescent Moon and two of the finest star clusters in the sky, the Pleiades and Hyades. I am looking forward to it!

Planetary Lineup on May 21st

With all of the talk about May 21st, I felt it would be helpful to guide observers to a genuine, heavenly lineup that will create a beautiful pattern in the morning sky on the 21st and 22nd. During the entire month of May, the four nearest planets to Earth have been creating a beautiful sight in the morning sky just ahead of sunrise. On May 21st and 22nd, Mars, Mercury and Venus form a compact cluster. Bright Venus is the "guide star" to help you find this grouping in the east. You will want to look about 30-45 minutes before sunrise, and you will need binoculars to see Mercury and Mars, but Venus will shine brightly despite the glare of the soon-to-be-rising Sun. Jupiter is also quite visible in the sky, but each day pulls away to the upper right (toward the south-east) a bit more from the other three planets. Note that the image of the view toward the east, which comes courtesy of Sky & Telescope Magazine, demonstrates that astronomers are confident we'll have something to see the morning of the 22nd!

Venus, Jupiter, Mars and Mercury in Conjunction

Four of the five most-visible planets are bunched together in the morning sky, creating beautiful patterns along the eastern horizon at dawn for the next few weeks. Each day the four planets change slightly in position, with bright Venus guiding your eyes to the right spot on the horizon where you can see these four points of light. Use binoculars to find all four planets - Mercury and Mars are much fainter than Jupiter and Venus - and use this amazing animation on the Sky & Telescope website to find the exact pattern as it changes each day. In San Francisco, you will want to look for this between 5:00 and 5:30 am, before the glare of the sunrise washes out the view of the planets.

Five Weeks of Planets in Conjunction

We are entering a period of time in which several planets are going to be in close proximity to each other, creating special alignments called "conjunctions." Mars, Mercury, Jupiter and Venus are all occupying the same region of the sky from our Earth-bound point of view, and as these planets and our own planet are all in motion around the Sun, the pattern we see in the sky changes quite a bit from one night to the next. At this time, all of these planets are emerging from the glare of the brightening dawn sky, appearing in the east just minutes before sunrise. Therefore, the initial conjunction on April 19th is best visible with the aid of binoculars. But this is just the start of a five week period in which these planets move very close to one another, creating a beautiful series of patterns for the early morning observer.

Our planet moves nearly 2 million miles per day in its orbit around the Sun. The planets are also moving at high speed around the Sun in their respective orbits. Mercury and Venus move the fastest relative to Earth, and because of their unique position inside the orbit of Earth, we see their changing locations in the early morning just before sunrise, or in the evening just after sunset. The other planets, including Mars and Jupiter for the next few weeks, move more slowly from our point of view and move more steadily from east to west from one morning to the next. I'll be posting a regular series of updates over the next month as the various conjunctions come and go. The important thing for the observer is to find a good eastern horizon, dust off the binoculars, and be ready to get up just before sunrise to see these cosmic alignments.

Celestial Companions in the Cold Dark Morning

January mornings are dark times, and when the sky is clear it is certain to be chilly outside. So I find the sight of the old Moon reassuring, a warm light that fades a bit each successive morning and guides the way through bright stars and planets along the ecliptic to the soon-to-be-rising-Sun. You can see this spectacle at its finest the next few mornings as the Moon moves a bit further eastward each day and passes near to some distinct celestial companions.

The Moon is passing now through Scorpius and the grey-white of the Moon stands in stark contrast to the red-orange of the star at the heart of the Scorpion, Antares. Moving close to Antares on Friday morning, the Moon continues toward the brilliant planet Venus on Saturday morning, and then slowly fades into the glare of sunrise on Sunday morning. My kitchen window faces south-east so I see this changing landscape each morning and I look forward to the coming days with clear skies in the forecast. If you rise before sunrise, take a moment to look out toward the south-east and enjoy the calm of this morning celestial grouping of close companions in the heavens.

Shimmering Early Morning Sky

As we approach the latest sunrise of the year (January 4th at 7:25 am in San Francisco), the morning sky remains dark enough to see stars until well after 6:00 am. That means that the early riser is rewarded with some lovely sights to close out 2010 and welcome 2011. Brilliant Venus dominates the sky each morning, shining bright in the South-East well before dawn. This week the waning Moon presents a changing landscape as it moves past Saturn, the bright star Spica (see diagram on the right), and then later in the week Venus and Mercury. Following the Solstice-Total-Lunar-Eclipse, the Moon is tracking downward on the Ecliptic, meaning that each Morning it is following the planets from high in the sky on a steep angle toward the horizon.

If you are not an early riser, don't despair. I'll have a post about the Winter skies soon. All you have to do is look up (especially if you are up at midnight on New Year's Eve and have clear skies). The Winter is a fantastic time to enjoy the stars.

Image courtesy of Sky and Telescope Magazine.

Brilliant Venus and Old Moon in the Dawn Sky

With sunrise at 7:00 in the morning, I find this time of year to be one in which I can do some early morning stargazing without having to change my morning routine. This week the waning Moon provides a lovely scene against the backdrop of brilliant Venus, bright Saturn and the bright star Spica. The illustration demonstrates what to expect in the eastern skies as the Moon shrinks each day on its way to the New Moon on December 5^th. If you are a morning person with an interest in astronomy, this will be an excellent week for you. Get out your binoculars for an especially riveting view of these heavenly bodies, and take in a few minutes of beauty about an hour before the sunrise.

KFOG Podcast - September 10, 2010

Another fun visit with Irish Greg of the KFOG Morning Show, today featuring a discussion of constellations to see this time of year (Sagittarius, Scorpius, The Summer Triangle) and the difference between an asterism and a constellation, plus deep-space objects you can see in the Milky Way with an ordinary pair of binoculars. And the latest happenings with the Moon and Venus, and an update on a great star party and lecture this weekend. All in 7 short minutes! Click here to listen.

Perspective of the Solar System

After weeks of foggy skies in San Francisco, the sky has started clearing, yielding spectacular sunsets and sky shows at Ocean Beach. I have been writing about (but not seeing much of) the amazing sight of the planets dancing across the evening sky. With the clear skies, the view was great, showcasing Venus and Mars very close together, with Saturn just to the lower right and the bright Zodiac start Spica (in Virgo) just to the upper left.

This configuration traces a curve in the sky and if you have a clear southern horizon you can "connect the dots" from this cluster of stars and planets to the south where bright Jupiter dominates the sky. Beyond that, the Moon is slicing across the lower southern sky, providing the observer with a nice visual of the Ecliptic, the line of the planets, Moon and Sun. This is a great way to visualize the path of the planets in the Solar System when you look out from our Earth-bound perspective.

Over the coming months, Mars and Saturn and eventually Venus fade, but the giant planet Jupiter will be dominating the Fall skies.

Trio of Planets

The evening sky brings us a trio of planets in a close grouping this week. The bright beacon of light, Venus, shines brightly and moves quickly from night to night, especially by comparison to the slower-moving Mars and Saturn. The image shows the view on Sunday August 8th, so looking at this earlier in the week you will find Venus lower and to the right of the other two planets, and after the 8th you will see Venus glide to the upper left of the two planets. We are witnessing the motion of Venus along its orbit around the Sun, moving much more quickly from our vantage point on Earth than Mars and Saturn. Venus will continue to dominate the evening sky for many weeks to come.

A Must See: Four Planets and the Moon

This week the sky features four of the brightest planets in a beautiful lineup in the sunset sky. The illustration on the left, borrowed from Sky & Telescope Magazine, demonstrates how the planets all align themselves in a path across the sky known as the Ecliptic. This line in the sky, actually a gentle curve from west to east across the south part of the sky, is the plane of the Solar System as viewed from our observing platform on Earth. We see fast-moving Mercury close to the Sun, then Venus, Mars and Saturn, a most impressive line-up.

To set this into perspective, the young Moon emerges from the glare of the Sun on Tuesday 13th, moving somewhat parallel to the Ecliptic but each day a bit farther south of the Ecliptic. This is because the orbit of the Moon around the Earth is slightly inclined to the rest of the bodies in the Solar System. And as we just had a Total Solar Eclipse on Sunday, the Moon is following a path away from the Ecliptic into what is called the "descending node" south of the Ecliptic.

I will be talking about this at the California Academy of Sciences at their Nightlife event this Thursday in Golden Gate Park. If you are in or near San Francisco, please join me on the roof for Star Tours!

Heavenly Line-Up

Over the past months the evening sky has been graced by a number of bright stars and planetary configurations. As summer approaches and these stars and planets move westward toward the sunset day after day, heavenly line-ups are emerging that are beautiful to see and are dynamic in nature, changing dramatically from one day to the next.

This evening the planet Venus moves into a very impressive alignment with the two “twin” stars of Gemini, Castor and Pollux. Although Venus is considerably brighter than the two stars, the pattern of the three celestial objects will be distinct, emerging from the sunset glow with Venus as the guide star and Castor and Pollux shining a short while later.

On the 13^th and 14^th, the trio is joined by the young crescent Moon. The combination of these heavenly bodies in the twilight should be an impressive sight indeed.

Planets and Bright Stars along the Ecliptic

This is a great time of year to enjoy the view of bright stars and planets demarcating the ecliptic. I am hosting a lot of star parties these days (last week in Tomales, this week in Fremont, next week in Healdsburg and the week after in San Mateo) and I always love to point out the ecliptic, the band across the sky where the planets and Moon are found in their wanderings across the heavens.

The ecliptic is the plane of the Solar System, the imaginary line across the sky that marks the orbits of the planets and the Moon. In a planetarium this can easily be shown, but under the heavens it is daunting to visualize this. I use a laser pointer to show the path across the sky, and that helps to visualize this, but right now the skies are cooperating to make this a bit easier for those of you without an amateur astronomer and a laser pointer :-)

Face South about 30-45 minutes after sunset and you will be looking toward the ecliptic. It stretches from the point of sunset to your right (West) where bright Venus gives you one reference point, then stretches up and toward the south to Castor and Pollux, the two twin stars of the zodiac constellation Gemini. Just to the upper left of the pair is bright orange Mars, and continuing left you encounter blue-white Regulus, the brightest star in the zodiac constellation Leo. Now the line of the ecliptic moves down toward the East, that is, down and to the left as you face South. Lower left of Leo is the planet Saturn, a bright, milky-white dot of light. And continuing to the lower left of Saturn is the bright star Spica, in the zodiac constellation Virgo.

Enjoy the tour, and if you have a star chart, put it to work so you can use these bright points of light to help you learn a few constellations. Even in the big city, all of these are visible.

The image on this page was copied from Nick Strobel's Astronomy Notes. Go to his site at www.astronomynotes.com for the updated and corrected version.

A Beacon in the Twilight

As the days grow longer and the last vestiges of twilight linger later in the evening, look to the West this week for some very beautiful planetary/celestial lineups. The week features fast-moving Venus passing very near to some of the most spectacular star clusters in the night sky, the Pleiades and the Hyades.

When you look into the twilight sky, the brightest objects shine majestically against the bright blue background. That is the case for Venus this week, as it is for the young crescent Moon each month when it shines low in the West in the first few days after new Moon. However, in order to see the star clusters near Venus, you will need to use binoculars. The stars are there to see, but the bright twilight makes them all but invisible to the naked eye. It's worth the time to get out and see this spectacle. Sunset in San Francisco is just before 8:00 pm, and the sky will be dark enough about 45 minutes to an hour after that.

Seeing Mercury in the evening sky

Mercury makes its way into the evening sky, visible shortly after sunset for the next few weeks. The fleet-footed planet never strays far from the Sun from our point of view, so we get glimpses of Mercury in the evening, then the morning before sunrise, and again in the evening several times a year. Right now Mercury is going to be easy to find because it will move near Venus this week. Venus is the bright evening "star" in the west, shining through the glow of dusk, and Mercury, although dimmer, will be fairly easy to spot now that you know where to look.

Old Moon, Young Moon

Every 29 1/2 days the Moon completes one cycle in its orbit around the Earth. For the last few days of the cycle we have an "old moon" and then just after New Moon we have the opportunity to see a very "young moon." I love the challenge of locating the very thin crescent Moon on the horizon, but when found, the reward is worth it, because the Moon always looks a jewel in the sky.

This week we've had a few opportunities to see the very old moon passing by Mercury in the dawn glare. After the New Moon on Saturday, find a good western horizon and try to locate the very young Moon in the glow of dusk. On Sunday 14th it will pass just next to Jupiter and Venus, extremely low on the horizon. You will want to have binoculars nearby to enhance the view. On Monday the Moon is higher in the west, and by Tuesday it is an easy target in the sunset sky. Well below the Moon on Tuesday, however, Jupiter and Venus have their closest approach for quite a while, being about 1/ 2 degree apart (a moon width). For this, you will want binoculars because the two planets will be just on the horizon after sunset.

Moon, Saturn, Corvus, Virgo and Venus

Now that the sky is remaining dark later and later each day, I am enjoying the early morning interplay of Solar System and stellar objects. This week provides a series of lunar alignments with Saturn, the constellation Corvus, the bright star Spica in Virgo, and finally Venus -- if you have an exceptionally clear, low eastern horizon. Sunrise in San Francisco is from 6:45 to 6:50 am this week.

Planetary Motion

The morning sky continues to be a busy place, showcasing just how much action is taking place in the Solar System. Saturn, a relatively slow moving outer planet is gradually rising up in the east, emerging each morning a minute or two earlier so that it will soon be a true morning star. As it graces the dawn sky just ahead of the sunrise, it is encountering the two fast-moving inner planets, Venus and Mercury. This week they have close encounters and beautiful alignments that will be a sight to see. The illustrations provide a sense of how far Venus and Mercury move over the course of just a few days. The passing of the waning Moon on the mornings of the 15th and 16th add a nice touch to an already impressive lineup of Solar System objects.