How to Photograph Tonight’s Spectacular Triple-Play Conjunction

Tonight the thin, 2-day-old crescent Moon will join Venus and Mars in the western sky at dusk for one of the most striking conjunctions of the year. The otherworldly trio will fit neatly with a circle about 1.5° wide or just three times the diameter of the full moon. No question, this will catch a lot of eyes around the world. Why not take a picture and share it with your friends? Here are a few tips to do just that.

Moon, Mars and Venus around 6:45 p.m. (CST) on Feb. 20 in the western sky. Be sure to look for the darkly-lit part of the moon illuminated by sunlight reflecting off Earth called earthshine. It’s a beautiful sight in binoculars. Source: Stellarium
Moon, Mars and Venus around 6:45 p.m. (CST) on Feb. 20 in the western sky. Be sure to look for the darkly-lit part of the moon illuminated by sunlight reflecting off Earth called earthshine. Source: Stellarium, author

You won’t need much for an easy snapshot. In bright twilight, point your mobile phone toward the Moon and tap off a few shots, taking care not to touch the screen too hard lest you shake the phone and blur the image. The phone’s autoexposure and autofocus settings should be adequate to capture both the Moon and Venus. Mars is fainter and may only show if you can steady your phone against something to allow for a longer exposure without blurring. Assuming you use your phone in its default wide view, the Moon, Venus and Mars will form a tight, small group in a larger scene.

Last night, Feb. 19, Venus and Mars were 1 degree apart. Tonight they'll be even closer at just over 1/2° with the Moon a degree or so to their right. Credit: Bob King
Last night, Feb. 19, Venus and Mars were 1°apart. Tonight they’ll be even closer at just over 1/2° with the Moon about 1° to their right. Details: 65 minutes after sunset (mid-twilight), camera on tripod, 35mm lens at f/2.8, ISO 400 and 6 second exposure. Credit: Bob King

Phones provide the highest resolution in their wide setting. If you zoom in, the Moon will be bigger but resolution or sharpness will suffer. Someday phones will be as good as digital single lens reflex cameras (DSLRs) but until then, you’ll need one of these or their cousins, the point-and-shoot cameras, to get the best images of astronomical objects.

You’ll also need a tripod to keep the camera still and stable during the longer exposures you’ll need during the optimum time for photography which begins about 30 minutes after sunset. That’s when your photos will capture all three objects without overexposing the Moon and making it look washed-out. Ideally, you want to see the bright crescent contrasting with the dim glow of the earthshine.

Venus and Mars photographed in mid-twilight with a 100mm telephoto lens at f/2.8. To prevent trailing of the planets, I cut the exposure in half to 4 seconds and increased the camera's ISO to 800. Credit: Bob King
Venus and Mars photographed in mid-twilight with a 100mm telephoto lens at f/2.8. To prevent trailing of the planets, I cut the exposure in half to 4 seconds and increased the camera’s ISO to 800. Credit: Bob King

Lucky for us, the Moon’s sharp form makes an ideal target for the camera’s autofocus. Frame an attractive landscape or ask a friend to stand in the foreground. Set your lens to its widest open setting (usually f/2.8-3.5) and the ISO (your camera’s sensitivity to light) to 800. The higher the ISO, the shorter the exposure you can use to capture an image, but high ISOs introduce unwanted noise and graininess. 800’s a good compromise. If you can manually set your exposure, start at 4 seconds.

Compose your photo and then focus on the Moon and gently press the shutter button. Check the image on the back screen. Are you on target or is it too dark? If so, double the time. If too bright, half it. As the sky gets darker, you’ll need to gradually increase your exposure. That’s when the Moon will start to wash out and the beautiful deep blue sky turn black or the color of your local light pollution. Around here, that’s pinkish-orange. I’ve got lots of orange sky photos to prove it!

The key to good photos in twilight is balancing the different types of lighting - dusk, the sunlit crescent, the earth-lit portion and the planets. Shoot pictures at a variety of exposures between about 30-60 minutes after sunset when the western sky is still aglow but the Moon is bright and obvious. Credit: Bob King
Mercury and the Moon on Jan. 31, 2014. Besides finding a scene you like, the key to good photos in twilight is balancing the different types of lighting – dusk, the sunlit crescent, the earth-lit outline and the planets. Shoot pictures at a variety of exposures starting about 35 minutes after sunset when the western sky is still aglow but the Moon is bright and obvious. Credit: Bob King

All told, you can use a mobile phone to shoot from about 25-40 minutes after sunset and a DSLR from 25 minutes to 75 minutes after. If you’re shooting with a standard 24-35mm lens, keep your exposures under 20 seconds or the Moon and planets will start to streak or trail. The Rule of 500 is a great way to remember how long a time exposure you can make with any lens before celestial objects start trailing. So, 500/24mm = 20.8 seconds and 500/200mm (telephoto) = 2.5 seconds. That means if you plan to shoot the conjunction with a longer lens, you’ll need to up your ISO to 1600 or even 3200 in late twilight to get a tack-sharp, motionless photo.

I screwed this photo up of the Moon, Jupiter and Mars by overexposing the sunlit crescent. Credit: Bob King
I screwed this photo up of the Moon, Jupiter and Mars by overexposing the sunlit crescent. It’s all part of learning the ropes, a task made much easier nowadays by simply checking the view screen of your camera and trying a different exposure. Credit: Bob King

Telephoto images are a bit more challenging, but they increase the size of the pretty trio within the scene. When shooting telephoto images (even wide ones if you’re fussy), shoot them on self-timer. That’s the setting everyone used before the selfie took the world by storm. Most timers are pre-set to 10 seconds. You press it and the camera counts down 10 seconds before automatically tripping the shutter, allowing you time to put yourself in a group photo.

In astrophotography, using the self-timer assures you’re going to get a vibration-free photo. If it’s cold out and you’re shooting with a telephoto, vibration from your finger pressing the shutter button can jiggle the image.

Good luck tonight and clear skies! If you have any questions, please ask.

See a Rare Comet-Moon Conjunction Tonight

I want to alert you to a rather unusual event occurring this evening.

Many of you already know about the triple shadow transit of Jupiter’s moons Io, Europa and Callisto. That’s scheduled for late tonight.

Earlier, around nightfall, the crescent moon will lie 1° or less to the south-southwest of comet 15P/Finlay. No doubt lunar glare will hamper the view some, but what a fun opportunity to use the moon to find a comet.

Finlay underwent a flare in brightness last week when it became easily visible in binoculars.

The farther south you live, the closer the moon will approach the comet tonight. This diagram shows the view from Tucson, Ariz. at nightfall when less than 1/2° will separate the two. At about the same time (~7 p.m. local time) the moon will occult or cover up a 6th magnitude star (seen poking out from its left side). Source: SkyMap
The farther south you live, the closer the moon will approach the comet tonight. This diagram shows the view from Tucson, Ariz. at nightfall when less than 1/2° will separate the two. At about the same time (~7 p.m. local time) the moon will occult or cover up a 6th magnitude star (seen poking out from its left side). Source: SkyMap

Though a crescent moon isn’t what you’d call a glare bomb, I can’t predict for certain whether you’ll still see the comet in binoculars tonight or need a small telescope instead. Most likely a scope. Finlay has faded some since its outburst and now glows around magnitude +8.5.

You can try with a 10×50 or larger glass, and if you don’t succeed, whip out your telescope; a 4.5-inch or larger instrument should handle the job.

Just point it at the moon at star-hop a little to the north-northeast using the map until you see a fuzzy spot with a brighter center. That’s your comet. The tail won’t be visible unless you’re using more firepower, something closer to 10-inches.

Comet Finlay in outburst on January 20, 2015 shows a beautiful parabolic-shaped head. Credit: Joseph Brimacombe
Comet Finlay in outburst on January 20, 2015 showing a beautiful parabolic-shaped head. Credit: Joseph Brimacombe

By the way, the father south you live, the closer the moon approaches Finlay. From the far southern U.S. they’ll be just 1/2° apart. Keep going south and parts of Central and South America will actually see the earth-lit edge of moon approach and then occult the comet from view!

UPDATE: Although light clouds marred the view I had difficulty finding the comet this evening in my 10-inch scope. It’s possible it’s further faded or my conditions weren’t optimal or both. No luck BTW in binoculars.

Half-Moon Makes Dramatic Pass at Uranus Tonight

Sunlight. Moonlight. Starlight. I saw all three for the first time in weeks yesterday. Filled with photons, I feel lighter today, less burdened. Have you been under the clouds too? Let’s hope it’s clear tonight because there’s a nice event you’ll want to see if only because it’s so effortless.

The half-moon will pass very close to the planet Uranus for skywatchers across North America this evening Sunday, Dec. 28th. Pop the rubber lens caps off those binoculars and point them at the Moon. If you look a short distance to the left you’ll notice a star-like object. That’s the planet!

Seattle, two time zones west of the Midwest, will see the two closest around 9:30 p.m. local time. Source: Stellarium
Seattle, two time zones west of the Midwest, will see the two closest around 9:30 p.m. local time. Source: Stellarium

You can do this anytime it’s dark, but the later you look the better because the Moon moves eastward and closer to the planet as the hours tick by. Early in the evening, the two will be separated by a couple degrees, but around 11:30 p.m. CST (9:30 p.m. PST) when the Moon reclines in the western sky, the planet will dangle like an solitary diamond less than a third of a lunar diameter away. When closest to the Moon, Uranus may prove tricky to see in its glare. If you hide the Moon behind a chimney, roofline or power pole, you’ll find it easier to see the planet.

The farther north you live, the closer the twain will be. Skywatchers in Japan, the northeastern portion of Russia, northern Canada and Alaska will see the Moon completely hide Uranus for a time. The farther west you are, the higher the Moon will be when they conjoin. West Coast states see the pair highest when they’re closest, but everyone will get a good view.

Binocular view from the desert city of Tucson around 10:45 p.m. local time tonight. Source: Stellarium
Binocular view from the desert city of Tucson around 10:45 p.m. local time tonight. You can see that the Moon is a little farther north of the planet compared to the view from Seattle. The 1,500 miles between the two cities is enough to cause our satellite, which is relatively close to the Earth, to shift position against the background stars. Source: Stellarium

When closest, the radically different character of each world can best be appreciated in a telescope. Pump the magnification up to 150x and slide both planet and Moon into the same field of view. Uranus, a pale blue dot, wears a permanent cover of methane-laced clouds where temperatures hover around -350°F (-212°C).

Though the moon will be lower in the sky, observers in the eastern U.S. and Canada will still see planet and moon only about 1/2 degree apart before moonset. Source: Stellarium
Though the Moon will be lower in the sky in the eastern U.S. and Canada when it’s closest to Uranus, observers there will still see planet and Moon only 1/2 degree apart shortly before moonset. Source: Stellarium

The fantastically large-appearing Moon in contrast has precious little atmosphere and its sunny terrain bakes at 250°F (121°C). And just look at those craters! First-quarter phase is one of the best times for Moon viewing. The terminator or shadow-line that divides lunar day from night slices right across the middle of the lunar landscape.

Shadows cast by mountain peaks and crater rims are longest and most dramatic around this time because we look squarely down upon them. At crescent and gibbous phases, the terminator is off to one side and craters and their shadows appear scrunched and foreshortened.

The day-night line or terminator cuts across a magnificent landscape rich with craters and mountain ranges emerging from the lunar night. Several prominent lunar "seas" or maria and prominent craters are shown. Credit: Christian Legrand and Patrick Chevalley / Virtual Moon Atlas
The day-night line or terminator cuts across a magnificent landscape rich with craters and mountain ranges emerging from the lunar night. Several prominent lunar “seas” or maria and prominent craters are shown. Credit: Christian Legrand and Patrick Chevalley / Virtual Moon Atlas

Enjoy the tonight’s conjunction and consider the depth of space your view encompasses. Uranus is 1.85 billion miles (2.9 billion km) from Earth today, some 7,700 times farther away than the half-moon.

A Spectacular Dawn Conjunction of Venus and Jupiter Set For August 18th

“What are those two bright stars in the morning sky?”

About once a year we can be assured that we’ll start fielding inquires to this effect, as the third and fourth brightest natural objects in the sky once again meet up.

We’re talking about a conjunction of the planets Jupiter and Venus. Venus has been dominating the dawn sky for 2014, and Jupiter is fresh off of solar conjunction on the far side of the Sun on July 24th and is currently racing up to greet it.

We just caught sight of Jupiter for the first time for this apparition yesterday from our campsite on F.E. Warren Air Force Base in Cheyenne, Wyoming. We’d just wrapped up an early vigil for Perseid meteors and scrambled to shoot a quick sequence of the supermoon setting behind a distant wind farm. Jupiter was an easy catch, first with binoculars, and then the naked eye, using brilliant Venus as a guide post.

Stellarium
The view looking eastward at dawn on August 18th, including a five degree telrad (red circles) and a one degree telescopic field of view (inset). Created using Stellarium.

And Jupiter will become more prominent as the week progresses, climaxing with a fine conjunction of the pair on Monday, August 18th. This will be the closest planet versus planet conjunction for 2014. At their closest — around 4:00 Universal Time or midnight Eastern Daylight Saving Time — Venus and Jupiter will stand only 11.9’ apart, less than half the diameter of a Full Moon. This will make the pair an “easy squeeze” into the same telescopic field of view at low power. Venus will shine at magnitude -3.9, while Jupiter is currently about 2 magnitudes or 6.3 times fainter at magnitude -1.8. In fact, Jupiter shines about as bright as another famous star just emerging into the dawn sky, Sirius. Such a dawn sighting is known as a heliacal rising, and the first recovery of Sirius in the dawn heralded the flooding of the Nile for the ancient Egyptians and the start what we now term the Dog Days of Summer.

To the naked eye, enormous Jupiter will appear to be the “moon” that Venus never had next weekend. The spurious and legendary Neith reported by astronomers of yore lives! You can imagine the view of the Earth and our large Moon as a would-be Venusian astronomer stares back at us (you’d have to get up above those sulfuric acid clouds, of course!)

Said conjunction is only a product of our Earthly vantage point. Venus currently exhibits a waxing gibbous disk 10” across — three times smaller than Jupiter — but Venus is also four times closer to Earth at 1.61 astronomical units distant. And from Jupiter’s vantage point, you’d see a splendid conjunction of Venus and the Earth, albeit only three degrees from the Sun:

conjunction
Earth meets Venus, as seen from Jupiter on August 18th. Note the Moon nearby. Created using Starry Night Education Software.

How often do the two brightest planets in the sky meet up? Well, Jupiter reaches the same solar longitude (say, returns back to opposition again) about once every 13 months. Venus, however, never strays more than 47.1 degrees elongation from the Sun and can thus always be found in either the dawn or dusk sky. This means that Jupiter pairs up with Venus roughly about once a year:

A list
A list of Venus and Jupiter conjunctions, including angular separation and elongations (west=dawn, east=dusk) from now until 2020. Created by author.

Note that next year and 2019 offer up two pairings of Jupiter and Venus, while 2018 lacks even one. And the conjunction on August 27th, 2016 is only 4’ apart! And yes, Venus can indeed occult Jupiter, although that hasn’t happened since 1818 and won’t be seen again from Earth until – mark your calendars – November 22nd, 2065, though only a scant eight degrees from the Sun. Hey, maybe SOHO’s solar observing successor will be on duty by then…

Venus has been the culprit in many UFO sightings, as pilots have been known to chase after it and air traffic controllers have made furtive attempts to hail it over the years. And astronomy can indeed save lives when it comes to conjunctions: in fact, last year’s close pairing of Jupiter and Venus in the dusk sky nearly sparked an international incident, when Indian Army sentries along the Himalayan border with China mistook the pair for Chinese spy drones. Luckily, Indian astronomers identified the conjunction before shots were exchanged!

Earth strikes back...
Earth strikes back… firing a 5mw green laser at the 2013 conjunction of Jupiter and Venus. Photo by author.

Next week’s conjunction also occurs against the backdrop of Messier 44/Praesepe, also known as the “Beehive cluster”. It’ll be difficult to catch sight of M44, however, because the entire “tri-conjunction” sits only 18 degrees from the Sun in the dawn sky. Binocs or a low power field of view might tease out the distant cluster from behind the planetary pair.

And to top it off, the waning crescent Moon joins the group on the mornings of August 23rd and 24th, passing about five degrees distant. Photo op! Can you follow Venus up into the daytime sky, using the Moon as a guide? How about Jupiter? Be sure to block that blinding Sun behind a hill or building while making this attempt.

Stellarium
The Moon photobombs the conjunction of Venus and Jupiter on the weekend of August 23rd. Credit: Stellarium.

The addition of the Moon will provide the opportunity to catch a skewed “emoticon” conjunction. A rare smiley face “:)” conjunction occurred in 2009, and another tight skewed tri-conjunction is in the offering for 2056. While many national flags incorporate examples of close pairings of Venus and the crescent Moon, we feel at least one should include a “smiley face” conjunction, if for no other reason than to highlight the irony of the cosmos.

A challenge: can you catch a time exposure of the International Space Station passing Venus and Jupiter? You might at least pull off a “:/” emoticon image!

Don’t miss the astronomical action unfolding in a dawn sky near you over the coming weeks. And be sure to spread the word: astronomical knowledge may just well avert a global catastrophe. The fate of the free world lies in the hands of amateur astronomers!

How Far is Mars from Earth?

This article was originally published on Aug 10, 2012. We’ve updated it and added this cool new video!

Sending spacecraft to Mars is all about precision. It’s about blasting off from Earth with a controlled explosion, launching a robot into space in the direction of the Red Planet, navigating the intervening distance between our two planets, and landing with incredible precision.

This intricate and complicated maneuver means knowing the exact distance from Earth to Mars. Since Mars and Earth both orbit the Sun – but at different distance, with different eccentricities, and with different orbital velocities – the distance between then is constantly changing

The first person to ever calculate the distance to Mars was the astronomer Giovanni Cassini, famous for his observations of Saturn. Giovanni made observations of Mars in 1672 from Paris, while his colleague, Jean Richer made the same observation from Cayenne, French Guiana. They used the parallax method to calculate the distance to Mars with surprising accuracy.

About every two years, however, the Earth passes Mars as they orbit around the Sun. Credit: NASA
Every two years, the Earth passes Mars as they orbit around the Sun, which causes it to appear like it is slowing down and moving in reverse in the sky (aka. “retrograde motion”). Credit: NASA

However, astronomers now calculate the distance to objects in the Solar System using the speed of light. They measure the time it takes for signals to reach spacecraft orbiting other planets. They can bounce powerful radar off planets and measure the time it takes for signals to return. This allows them to measure the distance to planets, like Mars, with incredible accuracy.

Distance Between Earth and Mars:

So, how far away is Mars? The answer to that question changes from moment to moment because Earth and Mars are orbiting the Sun. It also requires a little explanation about the orbital mechanics of each. Both Earth and Mars are following elliptical orbits around the Sun, like two cars travelling at different speeds on two different racetracks.

Sometimes the planets are close together, and other times they’re on opposite sides of the Sun. And although they get close and far apart, those points depend on where the planets are on their particular orbits. So, the Earth Mars distance is changing from minute to minute.

The planets don’t follow circular orbits around the Sun, they’re actually traveling in ellipses. Sometimes they’re at the closest point to the Sun (called perihelion), and other times they’re at the furthest point from the Sun (known as aphelion).

. Credit and copyright: Encyclopedia Britannica
Mars axial tilt and eccentricity as it orbits around the Sun. Credit and copyright: Encyclopedia Britannica

To get the closest point between Earth and Mars, you need to imagine a situation where Earth and Mars are located on the same side of the Sun. Furthermore, you want a situation where Earth is at aphelion, at its most distant point from the Sun, and Mars is at perihelion, the closest point to the Sun.

Earth and Mars Opposition:

When Earth and Mars reach their closest point, this is known as opposition. It’s the time that Mars appears as a bright red star of the sky; one of the brightest objects, rivaling the brightness of Venus or Jupiter. There’s no question Mars is bright and close, you can see it with your own eyes. And theoretically at this point, Mars and Earth will be only 54.6 million kilometers from each other.

But here’s the thing, this is just theoretical, since the two planets haven’t been this close to one another in recorded history. The last known closest approach was back in 2003, when Earth and Mars were only 56 million km (or 33.9 million miles) apart. And this was the closest they’d been in 50,000 years.

Opposition occurs when Mars and Earth line up on the same side of the Sun. The two planets are closest together at that time. Mars opposition occurs on May 22, when the planet will shine at magnitude -2.0 and with an apparent diameter of 18.6 arc seconds, its largest in years. Credit: Bob King
Opposition occurs when Mars and Earth line up on the same side of the Sun. The two planets are closest together at that time. Credit: Bob King

Here’s a list of Mars Oppositions from 2007-2020 (source)

  • Dec. 24, 2007 – 88.2 million km (54.8 million miles)
  • Jan. 29, 2010 – 99.3 million km (61.7 million miles)
  • Mar. 03, 2012 – 100.7 million km (62.6 million miles)
  • Apr. 08, 2014 – 92.4 million km (57.4 million miles)
  • May. 22, 2016 – 75.3 million km (46.8 million miles)
  • Jul. 27. 2018 – 57.6 million km (35.8 million miles)
  • Oct. 13, 2020 – 62.1 million km (38.6 million miles)

2018 should be a very good year, with a Mars looking particularly bright and red in the sky.

Earth and Mars Conjunction:

On the opposite end of the scale, Mars and Earth can be 401 million km apart (249 million miles) when they are in opposition and both are at aphelion. The average distance between the two is 225 million km. When Mars and Earth are at their closest, you have your launch window.

Every 26 months Mars is opposite the Sun in our nighttime sky. Since 1995, Mars has been at such an "opposition" with the Sun seven times. A color composite from each of the seven Hubble opposition observations has been assembled in this mosaic to showcase the beauty and splendor that is The Red Planet. This mosaic of all seven globes of Mars shows relative variations in the apparent angular size of Mars over the years. Mars was the closest in 2003 when it came within 56 million kilometres of Earth. The part of Mars that is tilted towards the Earth also shifts over time, resulting in the changing visibility of the polar caps. Clouds and dust storms, as well as the size of the ice caps, can change the appearance of Mars on time scales of days, weeks, and months. Other features of Mars, such as some of the large dark markings, have remained unchanged for centuries. Credit: NASA/ESA
Since 1995, Mars has been at such an “opposition” with the Sun seven times. A color composite from each of the seven Hubble opposition observations has been assembled in this mosaic to showcase the beauty and splendor that is The Red Planet. Credit: NASA/ESA

Mars and Earth reach this closest point to one another approximately every two years. And this is the perfect time to launch a mission to the Red Planet. If you look back at the history of launches to Mars, you’ll notice they tend to launch about every two years.

Here’s an example of recent Missions to Mars, and the years they launched:

  • MER-A Spirit – 2003
  • MER-B Opportunity – 2003
  • Mars Reconnaissance Orbiter – 2005
  • Phoenix – 2007
  • Fobos-Grunt – 2011
  • MSL Curiosity – 2011

See the trend? Every two years. They’re launching spacecraft when Earth and Mars reach their closest point.

Spacecraft don’t launch directly at Mars; that would use up too much fuel. Instead, spacecraft launch towards the point that Mars is going to be in the future. They start at Earth’s orbit, and then raise their orbit until they intersect the orbit of Mars; right when Mars is at that point. The spacecraft can then land on Mars or go into orbit around it. This journey takes about 250 days.

Communicating with Mars:

With these incredible distances between Earth and Mars, scientists can’t communicate with their spacecraft in real time. Instead, they need to wait for the amount of time it takes for transmissions to travel from Earth to Mars and back again.

Greetings from Mars!   I’m Spirit and I was the first of two twin robots to land on Mars. Unlike my twin, Opportunity, I’m known as the hill-climbing robot.     Artist Concept, Mars Exploration Rovers. NASA/JPL-Caltech
Artist’s impression of the Spirit Rover. One of two rovers that were part of MER program, the other was Opportunity, that began communicating back information that have helped NASA scientists characterize the Martian environment and geological history. NASA/JPL-Caltech

When Earth and Mars are at their theoretically closest point of 54.6 million km, it would take a signal from Earth about 3 minutes to make the journey, and then another 3 minutes for the signals to get back to Earth. But when they’re at their most distant point, it takes more like 21 minutes to send a signal to Mars, and then another 21 minutes to receive a return message.

This is why the spacecraft sent to Mars are highly autonomous. They have computer systems on board that allow them to study their environment and avoid dangerous obstacles completely automatically, without human intervention.

The distance from Earth to Mars is the main reason that there has never been a manned flight to the Red Planet. Scientists around the world are working on ways to shorten the trip with the goal of sending a human into Martian orbit within the next decade.

We have written many articles about the distance between planets here at Universe Today. Here are the distances between Earth and the Sun, Mercury, Venus, the Moon, Jupiter, Saturn, Uranus, Neptune, and Pluto. And here are Ten Interesting Facts about Planet Mars and How Long Does it Take to Get to Mars?

For more information, this website lists every Mars opposition time, from recent past all the way in the far future. You can also use NASA’s Solar System Simulator to see the current position of any object in the Solar System.

Finally, if you’d like to learn more about Mars in general, we have done several podcast episodes about Mars at Astronomy Cast. Episode 52: Mars. We have also done an episode explaining distances, Episode 10: Measuring Distance in the Universe.

Sources:

See Venus and the Moon Together in the Sky on September 8

Sky watchers worldwide are in for a treat Sunday evening September 8, 2013 as the waxing crescent Moon passes near the dazzling planet Venus. And for a select few, the Moon will actually pass in front of Venus, in what is known as an occultation.

The action has already started this week, as the Moon reached New phase earlier today at 7:36 AM EDT/11:36 UT. The appearance of the slim crescent Moon nearest to the September equinox marks the start of the Jewish New Year with the celebration of Rosh Hashanah, which this year began as early as it possibly can at sundown on September 4th. As per tradition, Rosh Hashanah formally begins when the sky is dark enough for three stars to be seen.  The convention established by Hillel II in 363 A.D. uses the mean motion of the Moon to fix the start dates of the Jewish luni-solar calendar, which means that occasionally Rosh Hashanah can start a day early. This also occurred in 2002.

The New Moon has also been historically an opportune time for nighttime military operations to commence —Desert Storm in 1991 and the raid against Bin Laden in 2011 were both conducted under the darkness afforded by the absence of moonlight around a New Moon. It’s yet to be seen if planners looking to conduct airstrikes on Syria are planning on taking advantage of the same conditions to begin operations soon.

Tonight, you can see the +1st magnitude star Spica less than two degrees away from -4th magnitude Venus. This places Venus at 100 times brighter than Spica and visible before sunset if you know exactly where to look for it.

The brightest star in the constellation Virgo, Spica is 260 light years distant and on the short list of nearby stars that will eventually go supernova. Fortunately for us, Spica is well outside of the ~100 light year radius “kill zone”.

You might just be able to spy the Moon and the -1st magnitude planet Mercury low to the west at dusk for the first time for this lunation tonight or (more likely) Friday night. This is also a great time to check out LADEE’s future home as it departs for lunar orbit from Wallops Island in Virginia on Friday night.

Hey, LADEE sitting on the pad atop its Minotaur V rocket with the slim crescent Moon in the background at dusk Friday night would be a great money shot, I’m just sayin’…

This weekend will see the Moon increase in illumination and elevation above the western horizon each evening until Spica, Venus, and the waxing crescent Moon fit within a four degree circle on Sunday night. The Moon will be 12% illuminated, while Venus is currently at a gibbous phase and 72% lit.

Looking west from latitude 30 north Sunday night from the US east coast... note that Mercury and Saturn are in the picture as well! (Created by the author in Stellarium).
Looking west from latitude 30 north Sunday night from the US east coast… note that Mercury and Saturn are in the picture as well! (Created by the author in Stellarium).

This will also present a good chance to see Venus during the daytime, using the nearby crescent Moon as a guide. This is a fun thing to try, and no gear is required! Though Venus may seem tough to find against the bright daytime sky, appearances are deceptive. With an albedo of 67% versus the Moon’s average of 14% Venus is actually brighter than the Moon per square arc second of size!

The Moon will also occult Spica on the evening of September 8th for observers in the Middle East and Europe right around sunset. Spica is one of four bright stars that the Moon can occult in the current epoch, along with Antares, Aldebaran, and Regulus. This is also part of a series of fine occultations of Spica by the Moon ongoing from 2012 to 2014.

Sundown on September 8th offers a special treat, as the 3-day old Moon passes less than a degree from Venus worldwide. The pair will fit easily into the field of view of binoculars or a telescope at low power and present an outstanding photo op.

And for observers based in Argentina and Chile, the Moon will actually occult Venus. Occultations are grand events, a split-second astronomical event in a universe that seems to usually move at a glacial pace. This particular occultation occurs for South American observers just before & after sunset.

The occultation of Venus by the Moon; the footprint over South America. (Credit: Occult 4.1.0.2).
The occultation of Venus by the Moon; the footprint over South America. (Credit: Occult 4.1.0.2).

We witnessed and recorded a similar pairing of Venus and the daytime Moon from the shores of our camp on Saint Froid Lake in northern Maine back in 2007:

Also, keep an eye out for a ghostly phenomenon known as the ashen light on the dark limb of the Moon. Also known as Earthshine, what you’re seeing is the reflection of sunlight off of the Earth illuminating the (cue Pink Floyd) dark side of the Moon. When the Moon is a crescent as seen from the Earth, the Earth is at gibbous phase as seen from the nearside of the Moon. Remember, the lunar farside and darkside are two different things! Earthshine can vary in brightness, based on the amount of cloud and snow cover present or absent on the Earth’s moonward side. My Farmer’s Almanac-consulting grandpappy would call ashen light the “Old Moon in the New Moon’s arms,” and reckon rain was a comin’…

Be sure to check out these astronomical goings on this weekend, and send those pics in to Universe Today!

Conjunctions to Watch For in July

The planets are slowly returning into view this month, bashfully peeking out from behind the Sun in the dawn & dusk sky. This month offers a bonanza of photogenic conjunctions, involving the Moon, planets and bright stars.

The action begins tonight on July 8th, as the waxing crescent Moon joins the planet Venus in the dusk sky. The razor thin Moon will be a challenge on Monday night, as it just passed New on the morning of the 8th at 3:14AM EDT/7:14 Universal Time (UT). The record for spotting the thin crescent with the naked eye currently stands at 15 hours and 32 minutes, completed by Stephen O’Meara on May 1990. Binoculars help considerably in this endeavor.  Wait until 15 minutes after local sunset, and then begin patiently sweeping the horizon.

Mr. Thierry Legault completed an ultimate photographic challenge earlier today, capturing the Moon at the precise moment of  New phase!

The Moon & Venus on the evening of July 9th from latitude 30 degrees north, about 30 minutes after sunset. (Created by the author using Stellarium).
The Moon & Venus on the evening of July 9th as seen from latitude 30 degrees north, about 30 minutes after sunset. (Created by the author using Stellarium).

This week  marks the start of lunation 1120. The Moon will be much easier to nab for observers worldwide on Tuesday night, July 9th for observers worldwide. The sighting of the waxing crescent Moon will also mark the start of the Muslim month of Ramadan for 2013. Due to the angle of the ecliptic in July, many northern hemisphere observers may not spot the Moon until Wednesday night on July 10th, about 6.7 degrees south west of -4.0 magnitude Venus.

Did you know? There are Guidelines for the Performance of Islamic Rites for Muslims aboard the International Space Station. It’s interesting to note that the timing of the rituals follows the point from which the astronaut originally embarked from the Earth, which is exclusively the Baikonur Cosmodrome in Kazakhstan for the foreseeable future of manned spaceflight.

Malaysia’s first astronaut, Sheikh Muszaphar Shukor observed Ramadan aboard the International Space Station in 2007.

From there, the crescent Moon fattens, meeting up with Saturn and Spica on the evenings of July 15th and 16th. The Moon will actually occult (pass in front of) the bright star Spica on the evening of July 15/16th at ~3:33UT/11:33PM EDT (on the 15th) for observers in Central America and western South America. The rest of us will see a near miss worldwide.

The waxing crescent Moon nearing Spica on the evening of the 15th at 10PM EDT. The Moon reaches 1st Quarter on the same evening at 11:18PM EDT. (Created by the author using Starry Night).
The waxing crescent Moon nearing Spica on the evening of the 15th at 10PM EDT. The Moon reaches 1st Quarter phase on the same evening at 11:18PM EDT. (Created by the author using Starry Night).

This is the 13th in a cycle of 18 occultations of Spica by our Moon spanning 2012-2013. Spica is one of four stars brighter than magnitude +1.4 that lie close enough to the ecliptic to be occulted by our Moon, the others being Antares, Regulus and Aldebaran. Saturn will lie 3 degrees from the Moon on the evening of July 16th.

Can you nab Spica and Saturn near the Moon with binoculars in the daytime around the 15th? It can be done, using the afternoon daytime Moon as a guide. Crystal clear skies (a rarity in the northern hemisphere summertime, I know) and physically blocking the Sun behind a building or hill helps.

The waxing gibbous Moon will also occult +2.8 Alpha Librae for South Africa on July 17th around 17:09UT & +4.4th magnitude Xi Ophiuchi for much of North America on the night of July 19th-20th.

And speaking of Regulus, the brightest star in the constellation Leo lies only a little over a degree (two Full Moon diameters) from Venus only the evenings of July 21st & the 22nd. 77.5 light years distant, Regulus is currently over 100 times fainter at magnitude +1.4. Can you squeeze both into the field of view of your telescope at low power? Venus’s mythical ‘moon’ Neith lives!

Venus can even occult Regulus on rare occasions, as last occurred on July 7th, 1959 and will happen next on October 1st, 2044.

But there’s morning action afoot as well. The planets Mars and Jupiter have emerged from solar conjunction on April 18th and June 19th, 2013 respectively, and can now be seen low in the dawn skies about 30 minutes before sunrise.

Mars and Jupiter in a close conjunction on the morning of July 22nd, about 30 minutes before sunrise as seen from latitude 30 degrees north. (Created by the author using Starry Night).
Mars and Jupiter in a close conjunction on the morning of July 22nd, about 30 minutes before sunrise as seen from latitude 30 degrees north. (Created by the author using Starry Night).

Mars approaches Jupiter in the dawn until the pair is only 0.79 degrees (about 48 arc minutes) apart on Monday, July 22nd. Mars shines at magnitude +1.6 and shows a tiny 3.9” disk, while Jupiter displays a 32.5” disk shining at magnitude -1.9 on this date. Conjunction occurs at about 7:00 UT/3:00 AM EDT, after which the two will begin to race apart. Mercury is visible beginning its morning apparition over 5 degrees to the lower right of the pair (see above).

Jupiter will reach opposition and reenter the evening sky on January 5th, 2014, while Mars won’t do the same until April 8th of next year. Weird factoid alert: neither Jupiter or Mars reach opposition in 2013! What effect does this have on terrestrial affairs? Absolutely none, well unless you’re a planetary imager/observer…

Mars also reaches its most northern declination of 2013 of 24 degrees in the constellation Gemini on July 16th at 7:00 AM EDT/11:00 UT.  Mars can wander as far as declination 27 degrees north, as last happened in 1993.

Finally, are you observing from southern Mexico this week and up for a true challenge? The asteroid 238 Hypatia occults a +7.4 magnitude star from 10:13-10:49 UT on July 10th in the constellation Pisces for up to 29 seconds. This event will be bright enough to watch with binoculars- check out our best prospects for asteroid occultations of stars in 2013 here and here.

Good luck, clear skies, and be sure to post those astro-pics in the Universe Today’s Flickr community!

Rare Spectacular Triple Planet Conjunction Wows World! – Astrophoto Gallery

Triple planets (Venus/Jupiter/Mercury) conjunction over Mont-Saint-Michel, Normandy, France on May 26. Credit: Thierry Legault –
www.astrophoto.fr
Update: See expanded Conjunction astrophoto gallery below[/caption]

The rare astronomical coincidence of a spectacular triangular triple conjunction of 3 bright planets happening right now is certainly wowing the entire World of Earthlings! That is if our gallery of astrophotos assembled here is any indication.

Right at sunset, our Solar System’s two brightest planets – Venus and Jupiter – as well as the sun’s closest planet Mercury are very closely aligned for about a week in late May 2013 – starting several days ago and continuing throughout this week.

And, for an extra special bonus – did you know that a pair of spacecraft from Earth are orbiting two of those planets?

Have you seen it yet ?

Well you’re are in for a celestial treat. The conjunction is visible to the naked eye – look West to Northwest shortly after sunset. No telescopes or binoculars needed.

Triple conjunction shot on May 26 from a mile high in Payson,Az.  4 second exposure, ISO200, Canon 10D, 80mm f/5 lens. Credit: Chris Schur- http://www.schursastrophotography.com
Triple conjunction shot on May 26 from a mile high in Payson,Az. 4 second exposure, ISO200, Canon 10D, 80mm f/5 lens. Credit: Chris Schur- http://www.schursastrophotography.com

Just check out our Universe Today collection of newly snapped astrophoto’s and videos sent to Nancy and Ken by stargazing enthusiasts from across the globe. See an earlier gallery – here.

Throughout May, the trio of wandering planets have been gradually gathering closer and closer.

On May 26 and 27, Venus, Jupiter and Mercury appear just 3 degrees apart as a spectacular triangularly shaped object in the sunset skies – which
adds a palatial pallet of splendid hues not possible at higher elevations.

And don’t dawdle if you want to see this celestial feast. The best times are 30 to 60 minutes after sunset – because thereafter they’ll disappear below the horizon.

The sky show will continue into late May as the planets alignment changes every day.

On May 28, Venus and Jupiter close in to within just 1 degree.

And on May 30 & 31, Venus, Jupiter and Mercury will form an imaginary line in the sky.

Triple planetary conjunctions are a rather rare occurrence. The last one took place in May 2011. And we won’t see another one until October 2015.

Indeed the wandering trio are also currently the three brightest planets visible. Venus is about magnitude minus 4, Jupiter is about minus 2.

While you’re enjoying the fantastic view, ponder this: The three planets are also joined by two orbiting spacecraft from humanity. NASA’s MESSENGER is orbiting Mercury. ESA’s Venus Express is orbiting Venus. And NASA’s Juno spacecraft is on a long looping trajectory to Jupiter.

Send Ken you conjunction photos to post here.

And don’t forget to “Send Your Name to Mars” aboard NASA’s MAVEN orbiter- details here. Deadline: July 1, 2013

Ken Kremer

…………….
Learn more about Conjunctions, Mars, Curiosity, Opportunity, MAVEN, LADEE and NASA missions at Ken’s upcoming lecture presentations:

June 4: “Send your Name to Mars” and “CIBER Astro Sat, LADEE Lunar & Antares Rocket Launches from Virginia”; Rodeway Inn, Chincoteague, VA, 8:30 PM

June 11: “Send your Name to Mars” and “LADEE Lunar & Antares Rocket Launches from Virginia”; NJ State Museum Planetarium and Amateur Astronomers Association of Princeton (AAAP), Trenton, NJ, 730 PM.

June 12: “Send your Name to Mars” and “LADEE Lunar & Antares Rocket Launches from Virginia”; Franklin Institute and Rittenhouse Astronomical Society, Philadelphia, PA, 8 PM.

May 25 conjunction over Malta. Canon 450D with a 55mm. lens and an exposure of 1/2 second at ISO 200 on a tripod.  Credit: Leonard Ellul-Mercer
May 25 conjunction over Malta. Canon 450D with a 55mm. lens and an exposure of 1/2 second at ISO 200 on a tripod. Credit: Leonard Ellul-Mercer
May 26 triple conjunction from Warwick, NY snapped from Canon Rebel, 100mm – 300mm lens.  Credit: Pietro Carboni
May 26 triple conjunction from Warwick, NY snapped from Canon Rebel, 100mm – 300mm lens. Credit: Pietro Carboni
Triple conjunction from  Hondo, Texas taken with a Nikon D800 @ ISO 400 and a 2 second exposure with a Nikon 300mm Lens at F/4.  Credit: Adrian New
Triple conjunction from Hondo, Texas taken with a Nikon D800 @ ISO 400 and a 2 second exposure with a Nikon 300mm Lens at F/4. Credit: Adrian New
Sunset conjunction with fast moving clouds on May 26 through 10 x 50 binoculars from a seashore town -Marina di Pisa, Tuscany, Italy. Credit: Giuseppe Petricca
Sunset conjunction with fast moving clouds on May 26 through 10 x 50 binoculars from a seashore town -Marina di Pisa, Tuscany, Italy. Credit: Giuseppe Petricca


Caption: Taken on 2013-05-23 from Salem, Missouri. Canon T1i, Nikkor 105mm lens. 297 1/4s at 1s interval. Images assembled by QuickTime Pro. Credit: Joseph Shuster

May 26 sunset conjunction from Princeton, NJ. Credit: Ken Kremer -kenkremer.com
May 26 sunset conjunction from Princeton, NJ. Credit: Ken Kremer -kenkremer.com
Triple Planetary conjunction over Onset MA. Shot with a Nikon d7000 1/200 f 4 iso 100 at 110mm. Credit: Phillip Damiano
Triple Planetary conjunction over Onset MA. Shot with a Nikon d7000 1/200 f 4 iso 100 at 110mm. Credit: Phillip Damiano
Panoramic view over Almada City and Lisbon at the Nautical Twilight, with the Full moon rising above the Eastern horizon (right side of the image), while at the same time but in the opposite direction, the planets Venus, Mercury and Jupiter, are aligned in a triangle formation, setting in the Western horizon (left side of the image).In this panoramic picture is also visible the smooth light transition in the sky, with the end of Nautical Twilight and the beginning of Astronomical Twilight (almost night), at right. Facing to North, is visible the great lighted Monument Christ the King and at the left side of it, part of the 25 April Bridge that connects Almada to Lisbon.  Canon 50D - ISO200; f/4; Exp. 1,6 Sec; 35mm. Panoramic of 10 images with about 200º, taken at 21h42 in 25/05/2013.  Credit: Miguel Claro - www.miguelclaro.com
Panoramic view over Almada City and Lisbon at the Nautical Twilight, with the Full moon rising above the Eastern horizon (right side of the image), while at the same time but in the opposite direction, the planets Venus, Mercury and Jupiter, are aligned in a triangle formation, setting in the Western horizon (left side of the image).In this panoramic picture is also visible the smooth light transition in the sky, with the end of Nautical Twilight and the beginning of Astronomical Twilight (almost night), at right. Facing to North, is visible the great lighted Monument Christ the King and at the left side of it, part of the 25 April Bridge that connects Almada to Lisbon. Canon 50D – ISO200; f/4; Exp. 1,6 Sec; 35mm. Panoramic of 10 images with about 200º, taken at 21h42 in 25/05/2013. Credit: Miguel Claro – www.miguelclaro.com
The triple conjunction of Venus, Mercury and Jupiter as seen over an Arizona desert landscape. Credit and copyright: Robert Sparks.
The triple conjunction of Venus, Mercury and Jupiter as seen over an Arizona desert landscape. Credit and copyright: Robert Sparks.
Jupiter, Venus and Mercury triple conjunction May 26 seen here reflecting off Chatsworth Lake in Chatsworth, NJ. Jupiter (on the left) was 2.4° from Mercury (upper-right in the sky) and 2.0° from Venus (bottom right in the sky), while Venus and Mercury were 1.9° apart. Venus was at 2.6° altitude. Canon EOS 6D, 105 mm focal length, 1.3 seconds, f/6.3, ISO 800. Credit: Joe Stieber - sjastro.org/
Jupiter, Venus and Mercury triple conjunction seen here reflecting off Chatsworth Lake in Chatsworth, NJ. Jupiter (on the left) was 2.4° from Mercury (upper-right in the sky) and 2.0° from Venus (bottom right in the sky), while Venus and Mercury were 1.9° apart. Venus was at 2.6° altitude. Canon EOS 6D, 105 mm focal length, 1.3 seconds, f/6.3, ISO 800. Credit: Joe Stieber – sjastro.org/
Triple conjunction on May 27 with WBZ radio towers south east of Boston.  Hampton Hill, Hull, MA.  Nikon D3x -iso200- 1.3 sec.at f2.8. Credit: Richard W. Green
Triple conjunction on May 27 with WBZ radio towers south east of Boston. Hampton Hill, Hull, MA. Nikon D3x -iso200- 1.3 sec.at f2.8. Credit: Richard W. Green

Bright Planetary Conjunctions Liven Up This Week’s Evening Sky

Planning a barbecue this weekend? You may want to top it off with a look at three bright planets shuttling about the western sky at dusk. Jupiter, Venus and Mercury gather for nearly a week of delightful alignments including three separate conjunctions staring right now. Mercury and Venus pair up on Friday; Mercury and Jupiter on Sunday and Venus and Jupiter on Monday. All three form a series of ever-changing triangular arrangements as the nights go by.

Three bright planets will highlight the northwestern sky this week and early next. Mercury is shown in pink and Jupiter in yellow. Stellarium
Three bright planets will highlight the northwestern sky this week and early next. Mercury is shown in pink and Jupiter in yellow. Time is 30 minutes after sunset facing northwest. They’ll be closest together – less than 3 degrees apart – on the night of the 26th. Stellarium

Brightest of the bunch is Venus followed by Jupiter and then Mercury. The key to seeing them all is a clear sky and unobstructed view of the west-northwest horizon. Best time for viewing is a half hour to 45 minutes after sunset. Although the diagrams make the planets look like largish disks, difference in size is a device to show their brightness. Bigger means brighter.

Mercury gradually climbs higher in the coming days, Venus will remain in nearly the same spot and Jupiter slowly drops off toward the horizon. Seeing three planets bunch up isn’t rare, but it is unusual – all the more reason to go for a look if your skies are clear. Alignments like this occur because all 8 planets lie in essentially the same flat plane. As we look across the solar system, sometimes near planets and far planets lie along the same line of sight and appear side-by-side in the sky. They may look close to each other but of course they’re millions of miles apart.

Positions of the planets on May 27. The arrow shows our point of view from Earth. Notice that the line of sight through all three takes our gaze near the sun. That's why they're only visible shortly after sunset in a bright sky. Click image to see a cool, interaction planet display. Credit: dd.dynamicdiagrams.com
Positions of the planets on May 27. The arrow shows the point of view from Earth. Notice that the line of sight through all three takes our gaze near the sun. That’s why they’re only visible shortly after sunset in a bright sky. Click image to see a cool, interactive planet display. Credit: dd.dynamicdiagrams.com

This week Venus is 154 million miles (248 million km) from Earth, Mercury 113 million (182 million km) and Jupiter a distant 562 million (904 million km). The planet position diagram above will give you a sense of their current arrangement in space.

Whenever you go planet-seeking in bright twilight, I always recommend bringing along a pair of binoculars. They penetrate haze and make finding these bright little dots much easier. Enjoy the show!

Venus Comes Out of Hiding! How to See Upcoming Conjunctions in the Evening Sky

Has Venus finally come out of hiding? For the past couple months it’s kept close to the sun, hidden in its glare, but come Friday, sky watchers in mid-northern latitudes may get their first shot at seeing the planet’s return to the evening sky.

It won’t be easy, but you’ll have help from the knife-edged crescent moon. Like a spring bloom raising its head from the dark earth, Venus will poke just 4 degrees above the western horizon a half hour after sunset. The moon will be about 2 degrees to the lower left of the planet. Seeing both requires a wide open view to the west and a clean, cloudless sky. It also helps to know when the sun sets for your location – easily found by clicking HERE.

Most any binoculars will prove useful for seeing Venus in twilight this week. One of my (inexpensive) favorites is a pair of Nikon Action 8x40s. Once you spot the planet in binoculars, try to see it with your naked eye. Credit: Bob King
Most any binoculars will prove useful for seeing Venus in twilight this week. One of my (inexpensive) favorites is a pair of Nikon Action 8x40s. Once you spot the planet in binoculars, try to see it with your naked eye. Credit: Bob King

Take along a pair of binoculars. They’ll help fish out both moon and planet in the bright twilight sky. It’s also advantageous to arrive at your viewing spot a little early. Enjoy the sunset, and then take a minute to make sure you’re binoculars are focused at infinity. If you don’t, Venus will be a blur and much harder to find. I usually focus mine on a cloud or the very farthest thing out along the horizon.

Once you’re all set, point your binoculars in the sunset direction and slowly sweep back and forth. Venus will be a short distance to the left or south of the brightest glow remaining along the horizon. Since most binoculars have a field of view of 4 or 5 degrees, when you place the horizon at the bottom of the view, the moon should appear in the middle of the field and Venus up near the top. Look higher and lower and farther left and right to be thorough. Once spotted in binoculars, take the visual challenge and see if you can find it without optical aid.

Venus punctuates colorful clouds low in the west in August 2008. Credit: Bob King
Venus punctuates a colorful sky low in the west at dusk in August 2008. Credit: Bob King

If you succeed, you’ll be rewarded with an elegant eyeful. Swamped in skylight, Venus will appear unusually meek but still possess its classic fiery brilliance. The newborn crescent will float just a degree and a half (three full moon diameters) away. From the U.S. east coast, the moon will be just 24 hours old; from the west coast 27 hours. Seeing such a young moon is a rarity in itself, but in the company of Venus that much finer.

Let’s say conditions aren’t ideal and you miss the pair on Friday. Well, try again on Saturday. The moon will be higher and much easier to see. Use it as a bow to shoot an imaginary arrow horizon-ward to Venus. And did I mention Jupiter? The planet that cheerily lit up our winter nights is now departing in the west. Watch for it to have a close encounter with Venus on the nights of May 27-28.

With its perpetual clouds, Venus would be a most distressing planet to any skywatcher unfortunate enough to live there. Yet it’s those same clouds that make it the most brilliant planet in the solar system seen from Earth. Clouds reflect sunlight splendidly. Combined with Venus’ proximity to Earth, it’s no wonder the planet earned the title of goddess of love and beauty.

As Venus revolves around the sun, we see it from a constantly changing perspective from our vantage point on Earth. In May, the planet is slightly to the left or east of the sun and making its reappearance as nearly "full moon" in evening twilight. Come Halloween it will appear like a half-moon. Credit: Bob King
As Venus and Earth revolve around the sun at different speeds, we see Venus from a constantly changing perspective. In May, the planet is slightly to the left or east of the sun and looks like a miniature full moon at dusk. Come Halloween it resembles a half-moon and a crescent at Christmas. Credit: Bob King

In the first 3 months of this year, Venus remained close to the sun in the morning sky and difficult to see. Then on March 28, it passed behind the sun on the opposite side of Earth’s orbit; astronomers call the lineup superior conjunction. Seen from Earth, Venus looked like a tiny full moon. We’re now about 6 weeks past conjunction and the planet has begun to peek out into the evening sky. At 98% illuminated, it still looks nearly full through a telescope, but that will change in the coming months as Venus approaches Earth in its speedier orbit. Watch for the goddess to grow larger in apparent size while at the same time slimming down her phase from full to half to crescent. Good luck getting re-acquainted this weekend!