Archive
Clouds part to reveal the planetary pile-up
The clouds of the past few days have moved out, so we have a chance to see the planets Venus, Mercury and Jupiter low in the northwest sky Monday night (if clouds from the next system don’t start to filter in). No telescope needed!
See Sky and Telescope’s web page for good maps of the sky and where to look.
http://www.skyandtelescope.com/observing/home/The-May-June-2013-Planet-Dance-192020551.html
These three planets were closest together in our skies last night, and some saw them between the clouds.
Here’s a photo I took on Thursday night of the planets… click to view it full size. Venus is the brightest dot, Jupiter is to its upper left and Mercury is the faint dot to Venus’ right.
They will be lined up diffrently tonight, as seen via the above link and this map from Carte du Ciel…
sky 25 minutes after sunset monday may 27…planets are 10 degrees above the horizon and getting lower – less than a fist held out at arm’s length
Jupiter and the Moon pose for a photo shoot
Overexposure can be a problem for photos for a family-friendly web site, but not in this case as Jupiter and the Moon patiently pose together while I fumble with exposures and other camera settings on my wonderful Canon Rebel XS on a sturdy tripod (thanks, kids for that great Christmas present!).
Here’s a 1/2 second exposure, ISO 400, f8 that gives an idea of the scene as seen by the human eye.
Jupiter is fainter and to the right of the bright, thin crescent moon.
Here a close up of the Moon, zooming in with a 250 mm variable lens; f8, 1/80 second, ISO 400, cropped from larger photo…
Moon, Canon SX 250mm lens on tripod
And the same moon, overexposed (!) to show a lunar mountain as a dot on the left (south) end of the crescent. (Cropped from a larger photo.)
Note the isolated lunar peak lit by the sun on the left end of the crescent
Jupiter’s moons are barely visible, even at the 250 mm setting. This is cropped from a larger scene to show the four moons to the lower right of the planet. (Look carefully for the faintest moon, farthest to the right. 1 second exposure at ISO 400.
Jupiter and 4 moons.
Can’t find Comet PanSTARRS yet
but here’s nice grouping of Jupiter and nearby (in the sky) star clusters…..
V-shaped Hyades cluster, with non-member Aldebaran as it’s brightest star and the Little-Dipper-shaped Pleiades on each side of very bright Jupiter
Step outside any clear night -give your eyes a few minutes to get adjusted to the dark and see this sight.
Lots of evening sky photos – Jupiter, Venus, Mercury – Orion and star clusters – Mars – and stars around them
Look for Mercury – a tiny dot down to the right of the tree. The two bright dots above are Venus (brightest) and Jupiter (highest and not as bright as Venus).
Mercury (lower right), Venus and Jupiter
Canon XS 20 seconds, F/20, 29mm, ISO 200.
If you turn around, Mars is rising in the east. It’s a red dot, brighter than the other stars around it from the constellation Leo the Lion. Leo looks like he’s jumping up into the sky (sorry I left off some of his head at the top of the frame).
Mars is the brightest 'star' in this photo. It's white, instead of red, because I overexposed the photo (20 seconds) to get the background stars.
As a bonus, here’s a photo of Orion (on the left) and the Pleiades (looking like a little dipper) to the upper right and the V-shaped Hyades cluster in between.
Orion, Hyades, Pleiades.
Click to enlarge and look for the little out-of-focus star in the stars below the bright three belt stars of Orion! That’s the Orion Nebula.
(Canon XS 20 seconds, F/4, ISO-400, 18mm.)
Also, I used the custom white balance feature on the Canon XS, which makes makes the sky look more normal, without the reddish glow often seen on long exposures in light-polluted skies.
Now go out and see it all for yourself – get where you can see the sky and block out bright lights!
Heads UP! for March 2011
Evening’s Bright Dot is Jupiter, Which Leads Us to Mercury
The Moon Runs Over a Star
March Comes in Like a Lion – Leo Rises
The Space Station and Solar Sail Make Appearances
Where are Saturn, Venus and Mars?
Don’t Forget Daylight-time Starts March 13th
Which Planet is Closest to Us?
Watch that bright dot in the western sky right after the sky gets dark in the evening. That’s the planet Jupiter. It will get lower in the sky every night, but as it gets down, it will pass the planet Mercury from the 13th through the 16th. If you have never seen Mercury in the sky, this is a great opportunity to see it. Mercury will be dimmer than Jupiter, but easy to see without optical aid with Jupiter nearby pointing the way.
Look out for the Moon this month as it cruises though our skies. On the 1st and the 31st, it lines up with Venus in the morning sky just before sunrise. It shares the evening twilight with Jupiter on the 6th and 7th. And the first quarter moon, when the moon looks half-full, is stuck high in the horns of Taurus the bull on the 12th. If you want to take up a challenge with your binoculars or telescope, the sight of a star instantly winking out when the dark limb of the Moon passes in front of it is exciting and educational (showing the lack of a substantial atmosphere on the Moon). The Moon covers μ Geminorum, a star normally easily seen without optical aid (magnitude 2.9) at the foot of one of the Gemini twins, on the evening of the 13th about 7:00pm in the New York City area. The moon’s glare may make it hard to find the star, so find the moon high up in bright twilight sky in advance of 7pm and look to the left of the moon with your optical aid to see the star. Then wait and watch for the moon to run it over.
Does March come in like a lion? Is our skies, it does, as Leo the lion rises into our evening skies from the eastern horizon. The bright winter constellations we have been enjoying seem to move quickly westward, as if in fear of our not-cowardly lion of the east.
Saturn is an object for late evening object through early morning. At 800 million miles away, it is tiny, but in a telescope, unmistakably Saturn with its ring. In your telescope, you’ll also see a nearby star. Saturn’s largest moon, Titan is fainter, but visible in telescopes larger than 3 inches wide.
Venus is still out there in the pre-dawn sky, only about one fist-width or so above the horizon.
Mars is still hiding in the glare of the Sun, but it is far enough from solar conjunction that scientists are listening again for signals from the Spirit rover, which hasn’t been heard from since the beginning of its Martian winter last March. The Opportunity rover is trundling along toward the large crater called Endeavour. Opportunity has been on Mars for 2511 Martian days and has 16½ miles on its odometer.
The International Space Station has bright evening-time overflights of our area now through the 13th and in the mornings starting on the 24th. The Nano-sail D solar sailing satellite has unfurled and NASA is having a contest to encourage photos of it as it travels across our skies like a moderately bright star. The best times for viewing Nano-sail D are in the evening through the 6th, and in the morning after that. Check spaceweather.com or heavens-above.com as the viewing times may change as the sail’s orbit is modified by solar wind pressure and bumps from the few atoms that make up our atmosphere at that altitude.
Remember that daylight time starts on March 13th, making the time of sunrise and sunset 6:59am and 7:07pm, respectively. Note that it’s not exactly a 12-hour period of daylight; one reason is due to the refraction of sunlight by Earth’s atmosphere from below the horizon lengthening daylight by a few minutes.
Which planet is closest to Earth most often? The surprising answer is Mercury. This year, for example, Mercury is the closest planet to Earth from March 14th through December 27th, when Mars becomes the closest planet to Earth. The distance from Earth to Venus is more than the distance from Earth to Mercury until January 7th, 2012, as Venus spends most of 2011 moving away from Earth in its slightly faster, inner orbit.
Jupiter and Uranus
Photos taken through my eight-inch dobsonian reflecting telescope with the camera attached to the telescope with a 2x barlow lens. This is called the prime focus method of taking photos through the telescope. This is the first time I’ve tried this set up on Jupiter or Uranus. The photo of the crescent Venus and Moon in an earlier post was done the same way. Before this, I’ve just held the camera up to the eyepiece.
Here are three photos with just the portion that shows Jupiter. The camera, a Canon Rebel XS, was set to exposures ranging from 1/250 to 1/600th of a second at ISO sensitivity of 800.
Jupiter1/250 sec
Jupiter 1/600 second
Jupiter 1/400 second
Same camera and telescope setup, but for Uranus 1/10 second ISO 1600.
Uranus 1/10 second exposure at ISO 1600
Jupiter and its four brightest moons through the telescope with the 2x barlow and the Canon XS. Jupiter is very bright so the camera can record the fainter moons.
Jupiter and its four brighest moons. Exposure 1/5 second, ISO 800. Not cropped - it's the whole photo as it was taken.
Click on the photo to see the full picture.
Fox Lane School Visits the Westchester Astronomers’ Star Party
Last Saturday, our Westchester Astronomers’ monthly star party included students from Fox Lane School. A mid-deck of clouds moved in from the south obscuring the sky so only Jupiter and few bright stars could get through the clouds. My 8-inch dobsonian reflecting telescope had enough light-gathering ability for us to see Jupiter almost all the time and Jupiter’s moons about 1/4 of the time. A magnification of 30 power was just right to give a nice size disk of Jupiter for everyone to see and keep its moons in the eyepiece for several people to see before the Earth’s rotation took the planet out of field.
Since we only focused on one object, the students could rotate through the line, looking at Jupiter itself first and on later visits, Jupiter’s moons when they were available. It was very satisfying was when even the youngest kids could describe the positions of each of the four moons visible that night.
The clouds even acted as a filter, bringing Jupiter’s dazzling light to a level that allowed our guests to pick out Jupiter’s remaining cloud band more easily.
Heads UP! for November 2010
Great Jupiter
Venus Rising
Comet Hartley2 – Ready for its Close Up?
Hey, Dude, Where’s My Ride (to space)?
Daylight Time Ends, Early Morning Darkness Pushed Back
Great Jupiter
Jupiter is that bright dot in the sky, the first ‘star’ you can see after sunset. Jupiter will be especially noticeable when the Moon comes into Jupiter’s neighborhood on the 15th and 16th. But even a nearly-full Moon can’t drown out the king of planets. Now that Jupiter is available in prime time, get your binoculars or telescope to see up to four tiny moons very close to the planet. Jupiter is banded – just one light brown band these days – but it can be seen even in small telescopes. Jupiter is so bright now that the band may be lost in the glare of the planet. Try reducing the brightness by holding one side of a pair of sunglasses between your eye and the eyepiece so see if you can improve the contrast and see the band.
Just one binocular-wide view to the left of Jupiter is a faint ‘star’ about a little fainter than one of Jupiter’s moons. That’s our solar systems’ seventh planet, the third largest – Uranus, five times further away than Jupiter. Does it look different from the stars in the same view? Since the stars are tiny points of light due to their great distance, planets often look more substantial and flicker less, even if they are as far away as Uranus.
Venus Rising
Some sharp-eyed observers with a clear southeastern horizon looking less than one-half-hour before sunrise will spot Venus rising just before the Sun during the first week of November. Venus will look like a tiny, very thin crescent moon in binoculars or a telescope. It will be very bright, but very deep into the dawn’s early light, it will be a challenge to find.
Early risers later in the month will see Venus blazing low in the predawn sky, with the star Spica and the planet Saturn above it. In a telescope, Saturn will be the ‘star’ with the very tiny ring around it. Saturn is all the way on the other side of the solar system now, so it’s really small, but Saturn’s rings are now tipping toward us and are easier to see than when the rings were edge-on earlier this year.
Mercury is hard to see low in the post-sunset sky and Mars is even harder to find.
Comet Hartley2 – Ready for its Close Up?
The spacecraft formerly known as ‘Deep Impact’, will be zipping by Comet Hartley2 as it zips by the earth. Since the impact part of Deep Impact, now called EPOXi, was left on Comet Tempel, the spacecraft will be just taking pictures. Radar from the giant radio bowl in Puerto Rico indicates that Hartley2 is somewhat dumbbell-shaped. See http://www.planetary.org/blog/article/00002742/ , and watch for photos at http://epoxi.umd.edu/ during and after the closest approach of the spacecraft to Hartley2 on November 4th.
Hey, Dude, Where’s My Ride (to space)?
The next-to-last launch of the USA’s Space Transportation System was scheduled for November 1st [next attempt Nov 30], on a mission to the International Space Station to install additional modules and to provide supplies and parts for. (Shuttle Discovery’s launch was postponed to Wednesday, November 3rd.) The end of an era in American access to space is approaching. When will the next era of American human space launches begin? In the meantime, the International Space Station’s mission continues, with astronauts being ferried by Russian Soyuz spacecraft. The ISS is a bright moving dot in the evening sky through November 17th and in the morning sky from the 24th through mid-December. Check web sites for times in your location.
Daylight Time Ends before sunrise on Sunday, November 7th. During the first week of November, here in the NYC area, the sun will appear to rise later (as late as 7:30am EDT) than it does during the shortest days of December (as late as 7:20am EST), allowing extra time in the morning for astronomy through the first week of November.
Jupiter blazes with fainter Uranus in the background
Jupiter and Uranus are within one degree of each other in the sky, so I was able to get both of them to sit for a portrait. Uranus is much fainter than Jupiter, but is easy to see, even in a small telescope.
I used my eight-inch dobsonian telescope and a wide (50mm) eyepiece to get them in the same view. Then I held my Canon Rebel XS up the eyepiece to snap their picture.
It took lots of trys to get a shot without too much wobbling. The Canon has a sensitive detector, but it still took a two second exposure to get fainter Uranus in the frame. The dots next to Jupiter are its four brightest moons.
Jupiter, its four brightest moons with Uranus to its right.
Here’s the same scene simulated by JPL, it’s reversed, since the telescope’s mirrors reverse the scene.
Jupiter, its four brightest moons and Uranus, simulated by JPL's Solar System Simulator
Heads UP! for August 2010
Heads UP! for August 2010
One blazing planet and three or four dimmer planets are low, but seeable, in the twilight soon after sunset. But they are upstaged by the rise of the King of the Planets, Jupiter. Also, around the middle of the month, tiny pieces from the distant comet Swift-Tuttle give us the Perseid meteor show. It’s a good year for viewing these fast-moving, bright meteors.
Stay out after sunset
Four planets are conveniently located in the western twilight sky an hour after sunset. Venus gets our attention at once. It’s beyond dazzling, but you’ll need a clear view of the western horizon. Look low in the part of the sky where the sun just set.
Venus has good company this month. If you watch the sky each night, you’ll notice that it looks like Venus is going to run over much fainter Mars and Saturn. They are fainter, but readily visible with some patience. Over several nights, Saturn (as bright as one of the brighter stars) appears to sidestep the on-rushing Venus, passing just above Venus around the 7th . Mars (a little brighter than Saturn) appears to slow down as it lingers in the vicinity of Venus all month. For the first half of the month, you can cover all three planets with your outstretched fist. Our gang of three are closest together for our WAA Observing Night on the 7th. Our fourth early evening guest, Mercury, is way down to the lower right of Venus, for the second and third week of August. The crescent Moon drives by on the 12th and makes a striking line-up after dark on the 13th.
So follow Venus this month as it brightens a bit but sinks lower toward the horizon. On September 1st, Venus will make a small group with Mars and the bright star Spica. It will be an especially cool sight in binoculars. Just aim at Venus and move a little to the right.
A Rain of Stars
Do you tilt your umbrella forward when you run in the rain? That’s a classic demonstration of why we see more meteors on the morning side of midnight than during the ‘prime time’ evening hours. In the morning, our side of the planet is in ‘front’, that is, in Earth’s direction of travel, as we move around the sun. That’s why we advise sky watchers to get up early in the morning for the most meteors. This year, the Perseid meteor shower has two features that may encourage those who are disheartened at getting up at 0200 (i.e., oh-too-early in the morning for me). First, the shower is predicted to peak around 9pm EDT on August 12th. Second, the Perseids is a display with many bright meteors. If your goal is to see some bright meteors, you should be just fine with whichever of the evenings near the 12th will be clear. Stay out after the sky gets dark (10pm or later) and lay out so you can see a large part of the sky comfortably, preferably with a sleeping bag to protect you from the mosquitoes and the dew, and you should get your share of ‘OMG, did you see that?’ meteors.
The Reign of a Planet
Jupiter is called the king of planets, when it (he?) rises after 10 o’clock early in the month you’ll know why. Brighter than anything except the Sun, Moon and Venus (as we saw earlier in the evening), it’s hard to miss his entrance. To view Jupiter and his retinue of 4 bright moons, you’ll need to stay out late or get up before dawn so you can get a good view in the morning sky. Use a telescope or steadily-held binoculars to see the moons and I think you’ll agree it worth the wait. The Moon comes by on the 26th.
Be a Beach Bum
You need a really dark location to see the Milky Way. So, it’s a great time to visit someone’s beach house. If you can get away from the lights, the Milky Way looks like a stream of high, thin clouds in a band soaring high into clearer skies away from the murky horizon. But also look low in the south- can you see the group of stars that looks like a teapot, low in the southern sky? If you look carefully, the Milky Way looks like ‘steam’ from the teapot. This area around the constellation Sagittarius is a wonderful visual playground for an observer with binoculars or a small telescope.
What’s that Bright Star Overhead?
Overhead, the sky and your imagination can transport you millions of miles or tens of light-years away. Vega is that bright star almost overhead on these August nights. Vega’s north pole points nearly at Earth, so the Sun (a dim, but visible star at Vega’s 25 light year distance) could be the pole star for Vega’s possible planets. Nearby, the top of the Northern Cross points like an arrow to a spot 7 degrees away that would mark the pole star – if you were on Mars. So look straight up and you can imagine being someone else’s pole star; and what it would be like standing on the north pole of Mars!
Fantasy Sky
For a great sky scene that you can’t see from Earth, go to NASA’s Solar System Simulator this month and ask it to give you a view of Venus as seen from Mars. Start with a 60 degree field of view. Earth is part of a striking scene with Venus and Jupiter. Mercury joins the scene about mid-month. I wonder if they’ll try to get a photo of this scene from one of the rovers.
The Moon is a great sight with binoculars or telescope. For August:
Last Quarter 8/3 New Moon 8/9 First Quarter 8/16 Full Moon 8/24
You can see lots of detailed craters and mountain ranges, especially from the 15th through the 18th.
The International Space Station
The ISS makes overflights of our area in the dawn skies from August 4th though 24th and in the evening skies from August 23rd through September 15th. Check nasa.gov, spaceweather.com or heavens-above.com for times when you can see the ISS and many other bright satellites for your location. The ISS is often as bright as Venus, so it’s easy to spot as it appears to lazily drift over us while orbiting the Earth at 18,000 miles per hour.
Have a telescope? Want to see how to use it?
Come to Pound Ward Ridge Park on Saturday evening, August 8th, members of the Westchester Astronomers will be there to help you use your telescope. Check the August WAA newsletter at http://www.westchesterastronomers.org/ for updates.
