Tag Archives: Venus

Evening moon, popular planets and extreme sports on Mars

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Face west-northwest tonight to see the moon near the star Regulus as well as a tight group of four bright sky objects – two stars an two planets. Created with Stellarium

The ambling moon is one day shy of first quarter phase tonight and lights up the sky near the star Regulus in Leo the Lion. Closer to the horizon, Venus and Mercury couple up with Gemini’s brightest stars Pollux and Castor, with bright Capella glimmering alone in the north.

Mercury and Venus join up for a conjunction (close pairing) on the 19th and 20th, while the moon passes near Saturn on June 18-19. Mars and Jupiter are both too close to the sun to see, but will soon return to morning twilight in the next several weeks.

A recent image from the Mars Odyssey spacecraft showing dark-bordered streaks caused by winds blowing around the dual craters’ walls. The dark areas are scoured of surface dust; the light zones are where the winds deposited their load of dust after being braked by the craters’ walls. Credit: NASA/JPL/ASU

Speaking of Mars, I came across some great images recently of wind streaks and dry ice “snowboard” trails on the Red Planet. Wind streaks can appear either dark or light-colored on Mars. When strong winds converge around craters and cliffs they can sweep away the lighter surface dust exposing the darker lava plains beneath. Craters can also slow down the winds, causing them to drop their loads of dust as light-colored streaks on the obstacle’s lee side. Sometimes both happen at the same time as in the photo above.

Mars Reconnaissance Orbiter photo of “linear gullies,” which may be explained by slabs of dry ice gliding down the slopes of sand dunes.  Different in form from other streaks and gullies on Mars, they can extend up to a mile (2 km) and end abruptly in pits.  Scale in meters at left. Click to enlarge. Credit: NASA/JPL-Caltech/Univ. of Arizona

While wind streaks make sense because of their earthly analogs, dry ice chunks gliding down the slopes of sand dunes on cushions of their own vaporizing gas sounds distinctly more alien. Yet that’s what NASA researchers believe is happening to create the zillions of narrow furrows seen along the slopes of some Martian sand dunes.

“I have always dreamed of going to Mars,” said Serina Diniega, a planetary scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and lead author of a report published online by the journal Icarus. “Now I dream of snowboarding down a Martian sand dune on a block of dry ice.”


Dry ice gliding on sand dunes 

Carbon dioxide frost coats the dunes during the Martian winter which lasts about twice as long one on Earth. Over time, the ice accumulates and gets compressed into slabs which can break off and glide downhill during the spring season. As frozen carbon dioxide (dry ice) changes directly from a solid to a gas on contact with the warmer sand, the gas pushes against the surface to create a cushion of air. The block rides the cushion all the way to the bottom where it continues to vaporize, forming a little pit at the end of the gully. Be sure to watch the short video – I think you’ll be delighted at the experiment using dry ice on sand dunes here on Earth.

Moon polkas with Mercury and Venus tonight

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Tonight the fresh lunar crescent will appear near Venus and Mercury low in the northwestern sky at dusk. Stellarium

Last Friday I photographed a polka festival and enjoyed seeing the pleasure on the couples’ faces as they hopped and turned about the dance floor. A good dance partner adds zest to life. A similar dance on a celestial plane happens tonight when the moon returns to the evening sky alongside Mercury and Venus. Watch for the trio starting about 25 minutes after sunset low in the northwestern sky.

The 2-day-old crescent will be easiest to see; from there hop over to bright Venus and fainter Mercury. You might not see Mercury at first, but if you wait for the sky to darken a little, it will eventually show. In case of haze, take along binoculars to make the finding easy.  Through a telescope Venus looks like a tiny gibbous moon while Mercury appears as an teenier half-moon.

More than 370 miles long (600 km) long and one of the largest fault scarps on the planet, Beagle Rupes cuts across Sveinsdottir crater at center. Beagle is named for the ship that carried Charles Darwin halfway around the world during his naturalist studies that led to the theory of evolution. (NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

The International Astronomical Union, keeper of the names for solar system bodies, recently approved 10 new names for Mercurian cliff-like faults called rupes. Rupes is the Latin word for cliff, and Mercury has an abundance of them. Long ago, as the planet’s core cooled and contracted, the outer crust responded in kind and contracted too. Where does extra crust go on a shrinking planet? Pieces of it are thrust up and over other areas of crust to create escarpments or cliffs. Geologists call these thrust faults; some are are hundreds of miles long and up to 2 miles (3 km) high.

Newly named Enterprise Rupes – the longest – stretches for 510 miles (820 km). In keeping with nomenclature rules, Mercury’s escarpments are named after ships of discovery. The U.S.S. Enterprise was launched on June 13,1874 , its first duty to survey the Mississippi River. Calypso Rupes was named for sea explorer Jacques Cousteau’s ship. To learn more about Mercury’s faults and other features, please visit the Mercury MESSENGER site.

Try to find Mercury soon before it drops back down into the sun’s glare in a week or so. This is the best time of year for northern hemisphere observers to see it in evening skies.

Comet PANSTARRS – Hit me baby one more time

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Comet L4 PANSTARRS on May 27 when Earth cut directly through the comet’s orbital plane giving us an edge-on view through the broad but narrow cloud of dust shed by the comet over the past few months. Click to enlarge. Credit: Martin Mobberley

If you’re looking for nature’s version of a straight-edge, look no further than Comet PANSTARRS. We had the opportunity to see its millions-mile-wide dust fan edge-on this weekend. Well, not all of us did. Moonlight spoiled the visual view but astrophotographers found ways around the moonlight to produce spectacular images.

Another view of PANSTARRS taken on May 28. The incredible tail gives the comet the appearance of a streaking fireball. The anti-tail measures about 7.5 degrees. Click for giant version. Credit: Michael Jaeger

Tail lengths estimates varied, but wide-angle amateur photos show it extending up to 16 degrees long. That’s 32 full moons side by side. The physical tail length captured in the photos is about 23 million miles (37.5 million km) long, but since it’s projected at an angle to its orbit, the full extent is considerably longer, likely approaching 93 million miles or the Earth-sun distance.

Too big for one photo, Jost Jahn took multiple pictures to create this mosaic of the PANSTARRS’ tail. Click to be taken to an interactive view. Credit: Jost Jahn

The beam-like tail is called an anti-tail because it points toward the sun in the opposite direction of a normal comet tail. It’s composed of dust particles shed over the past several months.

Not only do those bits of dust and rock line its orbital track, they also migrate outward into a vast sheet or cloud extending beyond PANSTARRS’ orbit. The short, broader tail is the normal dust tail, where dust particles are being pushed away from PANSTARRS in real time by the pressure of sunlight.

While the comet is still visible in 50mm binoculars in dark, moonless skies, the tail(s) will shorten and fade in the coming weeks as the distance between it and Earth widens.

Jupiter (left), Mercury (top) and Venus make an appearance between clouds over San Diego in this photo taken when the three were closest on May 26. Credit: Kevin Baird

Jupiter, Mercury and Venus are still clustered together low in the northwestern sky after sunset for the next few nights. My sky was mostly cloudy and I never got more than a glimpse of the three over the weekend.

Jupiter, Mercury and Venus framed by two apartment
buildings in Hamilton, Ontario Sunday night. Credit: Alex Sokolow

Others were more fortunate. Alex Sokolow saw them squeezed between two apartment buildings when the three were in their most compact arrangement on the 26th.

Even if you got hit with bad weather or circumstance this weekend, you can still see our planetary friends together the next few nights. Jupiter is dropping fast but passes closest to Venus tonight – the two will be just a degree apart.

Before Jupiter departs the scene it has its closest encounter with Venus this evening. This map shows the sky facing northwest about 30-45 minutes after sunset. Mercury’s about one “fist” high at that time. Created with Stellarium

Have you ever seen Mercury? If not, this is the best evening opportunity this year to do so for northern hemisphere sky watchers.

Cosmic patterns provide delight and insight

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A 22-degree halo circled the sun this past Friday afternoon. Halos like this one form in high cirrostratus clouds composed of microscopic hexagonal (6-sided) pencil shaped ice crystals. Sunlight refracted through billions of them spreads into a circle with a radius of 22 degrees. Click to learn more. Photo: Bob King

There’s always something happening in the sky. It’s a big place after all with many dimensions. There are near-space phenomena like ice halos and weather and a much deeper dimension that includes the most distant galaxies in the universe and the entire history of time.

If I were to pick one night to view the three bright planets at dusk, it would be tonight. Look very low in the northwestern sky starting about 40 minutes after sunset. Venus is the brightest of the three. Created with Stellarium

Patterns abound as well. Solar halos form when billions of ice crystals refract or bend sunlight and planets align when they appear along our line of sight. If you still haven’t seen the Jupiter-Venus-Mercury gathering in the evening sky, tonight’s the best night. All three worlds will fit inside a circle just 3 degrees (6 full moons) wide. Get lucky with a clear sky and wide-open view to the northwest and you’re good.

Saturn’s north polar hexagon photographed by the Cassini spacecraft. Each side of the hexagon measures about 8,600 miles long. The feature has persisted for at least 20 years. Credit: NASA/JPL-Caltech/SSI

Speaking of patterns, especially hexagons, I’m continually amazed by the quality of planetary photos taken by amateur astronomers. Philippine astrophotographer Christopher Go recently shared images of Saturn that blew me away. In them you can discern the planet’s north polar hexagon, a mysterious six-sided wave pattern centered on Saturn’s north pole.

You can easily make out the straight sides of Saturn’s north polar hexagon in this May 25, 2013 image taken through a 14-inch telescope. Credit: Christopher Go

It was first discovered during the Voyager flybys of the 1980s. Back then the pole was in sunlight. Until recently it was tilted away from the sun in shadow during the 7.5-year-long winter season in Saturn’s northern hemisphere. Now the hexagon’s back out in sunshine and the Cassini spacecraft has taken stunning photos of this only partially understood feature.

Photo taken by the Cassini probe last February shows Saturn’s polar hexagon emerging from shadow into sunlight during northern hemisphere spring. The Earth is shown for comparison. About 4 Earths would fit inside the feature. Credit: NASA/JPL-Caltech/SSI

The hexagon may be what physicists call a standing wave pattern. You can picture this by imagining two people holding either end of a jump rope and shaking it in sync. If done carefully, the rope will form a regular pattern of oscillating up and down waves that travel in place. Perhaps wavelike movements of air in the polar atmosphere create the standing hexagonal wave.

Animation of Saturn’s north polar hexagon. Credit: NASA/JPL/U. of Arizona

Ana Aguiar and her team at the University of Oxford have an alternative explanation. It turns out there’s a steep contrast in wind speeds on the planet at 78 degrees north latitude – the hexagon’s perimeter – that’s perfect for inducing instabilities in the atmosphere leading to the formation of oddball waves and eddies. They recently re-created a similar 6-sided pattern using fluorescent dyes in a dual-speed water tank in the laboratory. For a fascinating write-up on their experiment, please check out the Planetary Society’s Emily Lakdawalla’s blog on the topic.

Searching for the underlying cause of the patterns in nature has always been one of humanity’s specialties. Our lives have depended on it since the beginning when we tracked animals for food and followed the movement of the sun to forecast the seasons. That same spirit brought Saturn’s hexagon into the lab.

3 bright planets slow jam at dusk this week

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Jupiter, Venus and Mercury last night 35 minutes after sunset low in the northwestern sky. Details: 150mm lens at f/2.8, 1/30″, ISO 400. Photo: Bob King

Last night we finally cleared off after four solid days and nights of gray and rain. Sparkling low in the northwestern sky was a most welcome sight – Venus, Jupiter and Mercury. This week they will undergo to a series of remarkable gatherings in the early evening sky.

Venus leaped out immediately as the brightest of the trio. It stood 6 degrees above the horizon; that’s three fingers held horizontally at arm’s length. Jupiter jumped out next some 5 degrees to the upper left of Venus. Mercury, the dimmest of the the bunch, was very easy in binoculars but took a bit of concentration to see with the naked eye.

I’ve highlighted several nights of the triple planet gathering over the coming nights. Jupiter is colored yellow and Mercury pink to tell which is which. Created with Stellarium

This jam has just begun. Watch over the coming nights as the three planets move closer together to form a series of ever-changing jeweled triangles. Tomorrow night Mercury and Venus will be closest (1.4 degrees); Mercury and Jupiter on Memorial Day (2.3 degrees) and Venus and Jupiter on May 28 (1 degree).

All you need to see them is an unobstructed view to the west-northwest. You can begin your search about 30 minutes after sunset; get an early start because the planets set about an hour later. Binoculars can prove most helpful in case the sky’s hazy or if you have difficulty finding Mercury.

Left: If you could hover high above Earth’s north pole today and look down on the solar system, this is how the evening planets would be laid out. You can easily see how far they are from one another. At right, viewed from the flat plane of the solar system, they appear to bunch up. These occasional bunches caused by perspective are called conjunctions. Illustration: Bob King

As you can see from the nightly maps,  Mercury moves upward from the western horizon to join Venus, passes it and then teams up with Jupiter. Mercury moves rapidly because it orbits the sun most closely. Venus is also moving up from the west but more slowly, so it essentially stays in the same spot. Jupiter meanwhile drops down toward the western horizon. Earth’s motion around the sun is much faster than Jupiter’s causing the sun to literally “get in the way” between our two planets. From our perspective, Jupiter will soon disappear in the solar glare and won’t be seen again until early July when it reappears in the morning sky.

Although the trio may appear close to one another in the sky, they’re millions of miles from each other and the Earth. We see them together because they lie along the same line of sight for the coming week.

Watch as Venus, Jupiter and Mercury align after sunset

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The sky facing northwest this evening about 30-35 minutes after sundown. Venus and Jupiter should be relatively easy to spot provided you have an unobstructed view; Mercury might require binoculars. Stellarium

Hey, hey, hey. Three planets are now lining up in a neat row at dusk. Watch for the trio starting 30-35 minutes after sunset when they’ll be low in the northwestern sky.

The distance between Venus and Jupiter has shrunk over the past week and now stands at about 8 degrees or just shy of a fist held at arm’s length against the sky. Mercury finally joins the crew after emerging from the sun’s glare, though it will be the most challenging to see because of low elevation. As always when hunting planets in twilight, be a slacker and bring binoculars to make the job easy. Mercury will become easier to see by mid-week as it races up from the sun.

All three twilight planets appear close together near the sun in evening twilight is because they all lie in nearly the same line of sight (arrow) as seen from Earth. This view is a frame from a live orrery – click to watch the planets orbit the sun. Credit: dd.dynamicdiagrams.com

Venus is brightest at magnitude -3.4, while Jupiter and Mercury are near equals at -1.5 and -1.3 respectively. A week from now the three will all be clustered within a couple degrees of each other and form striking, triangle-shaped configurations that change night by night. I’ll have maps and times to look later this week. Get your cameras ready!

Earth’s ghostly light touches the crescent moon tonight

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The 2-day-old crescent moon shines over a bog north of Duluth, Minn. last night. Light reflected from the Earth faintly illuminates the moon’s full outline. Details: 200mm f/2.8, ISO 800, 1/2″ exposure. Photo: Bob King

Wow, the moon sure looked lovely last night. At dusk it was a sharp crescent against the blue sky, but later the entire disk was visible thanks to the the Full Earth. Full Earth? Had you been able to stand on the moon and look back in this direction, you would have seen our planet hanging like a big, blue ornament in the velvety black lunar sky. When the moon’s a sickle, light reflected from Earth – called earthshine – lights up the part of our satellite still in shadow.

Earth and moon phases complement one another. The top strip shows the moon phases and the bottom the corresponding Earth phases seen by an astronaut standing on the moon’s surface looking back at Earth. One difference: Earth appears almost 4 times bigger than the moon. Illustration: Bob King

Moon and Earth phases are complementary. A thin crescent in our sky means a person standing on the moon sees a nearly full Earth. A half moon here means a half-Earth there, and around the time of full moon, our lunar astronaut sees a crescent Earth.

A ramble across the earthlit portion of the moon in binoculars will reveal large dark areas (lunar seas) and several bright blotches – the craters Tycho, Copernicus and Aristarchus. Photo: Bob King

Sunlight reflected from our blue, cloud-streaked globe gently illuminates the full outline of the moon. Since the light is reflected rather than direct sunlight, earthlight is faint and rather mysterious-looking. From the surface of the moon, it resembles twilight here on Earth. The crescent itself is lit directly by the sun and appears brilliant in comparison.

Earthshine is twice-reflected sunlight – one bounce off the Earth to the moon and then a bounce back from the moon to Earth. Both moon and Earth absorb much of the sun’s light, which is why earthshine appears faint compared to the sunlit crescent. Illustration: Bob King

A full Earth reflects a lot of sunlight back at the moon, so earthshine is brightest when the crescent is thinnest. As the moon’s phase waxes to half and beyond, the Earth’s phase wanes, going from full to half to crescent. With less Earth to reflect sunlight, earthshine gets fainter and fainter. It also doesn’t help that the area for the Earth to illuminate shrinks as the sunlit portion of the moon grows ever larger night after night.

Jupiter (top left) and Venus (lower right) joined the crescent during twilight last night. Tonight the moon will be to the left of Jupiter. Photo: Bob King

Tonight’s crescent moon will be higher up in a darker sky, so the smoky earthlight should be even easier to see. When you step out for a look, you’ll also see a brilliant “star” a fist to the moon’s right. That’s Jupiter. If you have binoculars, take a minute to study the earthlit portion – you’ll see a surprising number of features there including several large dark areas (the lunar seas) and even a few craters, which look like bright spots.

Venus returns to the evening sky in grand style tonight

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Venus returns like a spring flower to evening twilight this month. This was the view last night 35 minutes after sunset looking low in the northwestern sky. Photo: Bob King

Guess who’s finally come out of hiding? Yep, it’s Venus, a planet we’ve seen neither hide nor hair of for months. Venus has been masked by the sun’s glare since late January for northern hemisphere sky watchers. Not anymore.

Like a child letting go of her parents, the brightest planet of them all is finally stepping away from the sun. You can see her for yourself chaperoned by a remarkably thin moon low in the northwestern sky beginning 20-30 minutes after sunset tonight.

I made my first attempt to catch a glimpse of the planet last night, figuring it might only show in binoculars. Boy, was I surprised. Although only 4 degrees high, Venus jumped right out in binoculars and was also plainly seen without optical aid. I followed the lovely “evening star” from 20 minutes past sunset for at least another 20 minutes before it sunk into the trees.

Watch for a wonderful close conjunction of returning Venus and a one-day-old crescent moon tonight. This map shows the sky facing west-northwest 30 minutes after sunset. Tomorrow night the moon will have moved up and away from the planet toward its next encounter with Jupiter. Stellarium

Tonight will be an extra special one for Venus watchers. The goddess of beauty and love will be joined by an extremely thin crescent moon for a brief time after sunset. I encourage you to find a spot with wide open view to the west-northwest to see the show.

Find your sunset time HERE and then arrive at your selected spot a few minutes after sundown. Bring binoculars so you can start scanning about 20 minutes later. Look a short distance to the left of the “sunset point”, that telltale bright glow along the horizon indicating where the sun has gone down. I don’t which you’ll see first – moon or planet – but once you find one, you’ll find the other. They should be a ravishing sight in binoculars!

By tomorrow night the moon will be well above Venus on its way toward Jupiter. Speaking  of which, Jove and Venus – with Mercury thrown in for good fun – will have their own close encounter May 27-29. The triple gathering promises to be the naked-eye highlight of the month, but more on that later.

The ever-changing geometry between Earth and Venus as the two planets orbit the sun causes Venus to go through phases just like the moon. In the evening sky, the planet is to the left or east of the sun; when visible at dawn, it’s to the right or west of the sun. Illlustration: Bob King

If the weather doesn’t cooperate tonight, you can use the moon again Saturday night to point you to the planet. Venus gleams about one fist held at arm’s length to the lower right of the lunar crescent.

As spring gives way to summer, Venus will pull away from the sun and slowly become more easily visible at dusk. Right now it’s on the far side of the sun from Earth and appears like a tiny full moon through a telescope. During the remainder of the year its phase will change from full to half (at Halloween) and finally a crescent at Christmas as the speedier planet catches up with our own.

Concealed planets exposed plus it’s spring break on Mars

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The sun and its pack of planets photographed earlier today by the coronagraph aboard the SOHO observatory. The sun (white circle) is blocked by an opaque disk so astronomers can study the streaky solar atmosphere called the corona. Credit: NASA / ESA

Half the planets have gone into hiding. Mercury is too low in the dawn sky for northern hemisphere skywatchers, and Mars, Venus and Uranus are gathered around the sun concealed by its glare. Only Jupiter and Saturn remain available for our viewing pleasure.

Still, it’s hard to keep planets hidden away when you’ve got the eyes of the Solar Heliospheric Observatory (SOHO) on your side. SOHO orbits around a stable region of space called the L1 Langrangian point where the gravity of Earth balances that of the sun.

SOHO orbits about a million miles ahead of Earth in line with the sun in a small “halo orbit” around the L1 Lagrangian point. From this vantage point it keeps the sun and Earth in view 24/7. Credit: Office of Naval Research

From this prime observing spot, scientists use SOHO’s cameras to study the sun in many wavelengths or colors of light. Special devices called coronagraphs block the overly-bright solar disk with a metal stop to allow viewing of the sun’s outer atmosphere or corona. They also show other objects in the field of view like comets and the current gang of planets – Uranus, Venus and Mars.

Since the planets are very near one another, lots of interesting lineups will happen in the coming days. Venus reaches superior conjunction on March 28 (tomorrow) when it lines up on the opposite side of the sun from Earth. Six hours later it’s only one degree (two full moon diameters) below Uranus. An hour after, Uranus is in conjunction with the sun. Then on April 6-7 Venus and Mars will be in conjunction just half a degree apart. Is this beginning to sound like a barn dance?

One thing to remember about conjunctions – the planets involved are not physically close; they only appear to be because we see them in the same line of sight. If you’d like to watch all these interesting encounters, check out SOHO’s latest coronagraph image.

Approximately every 26 months, Mars passes almost directly behind the sun from Earth’s perspective. During this time, NASA will halt communications with the two rovers. Credit: NASA/JPL-Caltech

For us, Mars’ proximity to the sun is interesting but inconsequential. Not so for the Curiosity mission. On April 17 the planet is in conjunction on the opposite side of the sun from Earth. From our perspective, Mars will appear extremely close to the sun’s brilliant disk. Radiation from solar flares and high-speed subatomic particles in the sun’s corona can disrupt radio transmissions between the two planets during close alignments like this one. To prevent compromised radio commands from reaching either Curiosity or the older Opportunity rover, mission controllers will temporarily suspend transmissions from April 9 to 26.

Wide angle view of Yellowknife Bay taken by one of Curiosity’s hazard avoidance cameras on March 27, 2013. The rover recently resumed science operations after recovery from a computer glitch. Credit: NASA/ JPL

Communications from Mars to Earth will also be reduced. To stay in touch, Curiosity will send daily beeps to Earth. Meanwhile both rovers and orbiting Mars satellites will continue science operations. Data gathered will be stored and then beamed to Earth in early May. The rovers’ spring break will be tame by earthly standards; both will stay put during the interval to prevent any shenanigans.

The bright star Sirius and planet Jupiter perform a balancing act on either side of Orion’s Belt this month and next. This may shows the sky facing southwest around 8:30 p.m. in late March.  Maps created with Stellarium

Did I mention there are still two great planets out at night? Jupiter stands high in the west-southwest at nightfall. It’s the brightest object in that direction. Saturn comes up later around 11 o’clock in the southeast about one extended fist to the lower right of Spica. The full moon will be near Spica tonight and Saturn on Thursday night. Much to see for all!

The full moon will swing by both Spica (tonight) and the planet Saturn tomorrow night. This map shows the sky facing southeast around 11:30 p.m.

Planetary perspectives inspire appreciation for the little things

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Venus is the bright “star” seen among Saturn’s rings in the photo taken by Cassini late last year. The bright arc is Saturn’s atmosphere glowing in backlit sunlight. Light reflected from the rings faintly illuminates the planet. Click to enlarge. Credit: NASA/JPL-CalTech

Nothing beats stepping back to gain a little perspective. NASA recently released a pretty picture of Venus peering through Saturn’s rings. The photo was taken on Nov. 10, 2012 when the Cassini spacecraft orbited the shadowed side of the ringed planet, so we see the rings and atmospheric edge of Saturn backlit by the sun. Venus is a pinprick of light nearly a billion miles away shining through the veil of icy bits that compose the rings.

Venus as seen this morning March 6, 2013 by SOHO’s camera. An opaque disk covers the sun (white circle) allowing astronomers to study the streaky solar atmosphere called the corona.  Venus is currently about 159 million miles from Earth. Credit: NASA/ESA

We also have a more recent photo of Venus taken by the Solar and Heliospheric  Observatory (SOHO) from a different point of view. This picture was taken earlier this morning and shows Venus nearby southwest of the sun. SOHO is parked near the L1 Lagrange point, a spot in space 1 million miles forward of Earth in the direction of the sun. Here the planet’s gravity balances that of the more distant sun allowing the craft to hover in equilibrium with its eye ever focused on the sun. Due to gravitational tugs from the moon and planets, SOHO fires its thrusters every few months to remain in position.

As Venus revolves around the sun, we see it pass through phases just like the moon. Today Venus is near the sun in the sky and appears like a nearly full moon. On the 28th it will be in conjunction and farthest from Earth on the opposite side of the sun. Illustration: Bob King

Venus might look like it’s in the foreground in the SOHO image, but it’s really in the background. On March 28 the planet will pass through superior conjunction when it will appear closest to the sun but located on the farside of its orbit behind it. After that date Venus begins its slow trek back into the evening sky as it comes round to the left or east of the sun. Watch for it to re-appear at dusk in late May.

Venus and Earth are nearly invisible in this wide angle view that includes the sun taken by the Voyager 1 spacecraft in 1990. Click to see the BIG version. Credit: NASA

A tight crop of the wide Voyager 1 photo clearly shows the pale blue dot of Earth. It’s caught in a streak of lens flare caused by the camera pointing directly at the sun. Everything we care about most deeply is contained in that minute fleck of light. Credit: NASA

Let’s pull back a bit more. What do Venus (and Earth) look like from 4 billion miles away, the way the Voyager 1 space probe saw them on Valentine’s Day 1990? Dots of course! Take a close look and you just might be able to see them in the photo. They’re much more obvious the full-resolution image, which can be had for a click.

Earth and the moon from 114 million miles away in the vicinity of Mercury photographed in 2010 by MESSENGER. Click to enlarge. Credit: NASA

Before we wrap up, let’s move in again a little closer and enjoy a picture of the dynamic duo of moon and Earth taken by the Mercury MESSENGER spacecraft from 114 million miles away. While not shot from the planet Mercury, the perspective is nearly identical. Doesn’t it make you feel a little exposed looking at these photos? I mean, there’s so much nothing out there compared to the bits of something. Time to hug my kids again.