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Posts Tagged ‘Jupiter & Galilean Moons’

0802030553dz
Above: Waning Crescent Moon at 5:53 AM CDT August 2, 2013 (10:53 UT), 8″ reflector telescope with 25mm eyepiece.

Below: Jupiter and its four largest Moons offer an ever-changing space-scape, though in the photo below you can’t see Io, which was transiting Jupiter’s face at the time.
0802030529jupiter25mm2xb
From left to right: Ganymede, Europa, Jupiter, Callisto, 5:29 AM CDT (10:29 UT).

Below: 29 minutes later, the lightening sky helps me photograph Jupiter’s atmospheric cloud belts. 5:58 AM (10:59 UT):
0802030558bjupiter25mm2xb
When the sky is darker, the photometer on my cell phone camera tries to take in as much light as possible, resulting in loss of planetary detail due to overexposure. But the lightening sky floods the camera with light, causing the photometer to kick down the light level, revealing more detail. Just something I’ve learned as a low-budget astrophotographer. :O)

Jupiter photos with 8″ reflector telescope, 25mm eyepiece and 2x Barlow. All with LG VX8360 cell phone camera.

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Venus and Jupiter are the two brightest planets, and these days Jupiter is appearing as a brilliant “morning star” in the east before dawn, whereas Venus is appearing as a bright “evening star” in the west after sunset.

Below: Jupiter and dimmer Mars close together in the predawn sky.0729030523jupitermars7x35
Mars is left center, brighter Jupiter is upper right. 5:23 AM CDT July 29, 2013, 7×35 binoculars.

Beautiful skies like this one keep me getting up before dawn:
0729030551

Below are photos of Mars (currently quite far away), Jupiter, and Venus shown at the same magnification:

0729030534mars25mm Mars at 5:34 AM CDT July 29, 2013 (10:34 UT)
Angular diameter 3.89 arc seconds
97.9% illumination
Distance from Earth 223,525,179 miles (359,728,906 km)
0729030527cjupiter25mm2xb Jupiter and Galilean Moons at 5:27 AM CDT July 29, 2013 (10:27 UT)
Left to right: Jupiter, Europa, Callisto, Io, Ganymede
Jupiter’s angular diameter 32.82 arc seconds
99.8% illumination
Distance from Earth 557,683,749 miles (897,504,995 km)

The following photos are all of Venus. Venus passed around the far side of the Sun (superior conjunction) on March 28, and is now gradually approaching the Earth once again:

0728031915cvenus25mm2xb 7:15 PM CDT July 28, 2013 (00:15 UT July 29, 2013)
Angular diameter 12.37 arc seconds
83.6% illumination
Distance from Earth 125,386,985 miles (201,790,791 km)
12:05 PM CST, November 19, 2012 (18:05 UT)
Angular diameter 12.25 arc seconds
85.6% illumination
Distance from Earth 126,593,857 miles (203,733,064 km)
1:12 PM CDT, October 12, 2012 (18:12 UT)
Angular diameter 14.69 arc seconds
74.6% illumination
Distance from Earth 105,565,517 miles (169,891,262 km)
2:00 PM CDT, September 21, 2012 (19:00 UT)
Angular diameter 16.83 arc seconds
67.3% illumination
Distance from Earth 92,101,088 miles (148,222,333 km)
8:26 AM CDT, September 10, 2012 (13:26 UT)
Angular diameter 18.36 arc seconds
62.7% illumination
Distance from Earth 84,452,528 miles (135,913,169 km)
10:17 AM CDT, September 4, 2012 (15:17 UT)
Angular diameter 19.31 arc seconds
60.1% illumination
Distance from Earth 80,311,754 miles (129,249,240 km)
1:15 PM CDT, August 21, 2012 (18:15 UT)
Angular diameter 22.02 arc seconds
53.5% illumination
Distance from Earth 70,401,199 miles (113,299,747 km)
7:36 AM CDT, August 13 2012 (12:36 UT)
Angular diameter 24.07 arc seconds
49.1% illumination
Distance from Earth 64,429,600 miles (103,689,390 km)
1:39 PM CDT, August 6, 2012 (18:39 UT)
Angular diameter 26.05 arc seconds
45.2% illumination
Distance from Earth 59,516,628 miles (95,782,727 km)
8:52 AM CDT July 30, 2012 (13:52 UT)
Angular diameter 28.56 arc seconds
40.6% illumination
Distance from Earth 54,298,771 miles (87,385,401 km)
5:49 AM CDT July 22, 2012 (10:49 UT)
Angular diameter 31.96 arc seconds
34.9% illumination
Distance from Earth 48,512,519 miles (78,073,332 km)
9:18 AM CDT July 13, 2012 (14:18 UT)
Angular diameter 36.52 arc seconds
27.9% illumination
Distance from Earth 42,450,876 miles (68,318,063 km)
11:56 AM CDT July 3, 2012 (16:56 UT)
Angular diameter 42.79 arc seconds
19.0% illumination
Distance from Earth 36,238,688 miles (58,320,514 km)
11:21 AM CDT June 27, 2012 (16:21 UT)
Angular diameter 47.07 arc seconds
13.4% illumination
Distance from Earth 32,940,927 miles (53,013,283 km)
8:38 AM CDT June 21, 2012 (13:38 UT)
Angular diameter 51.42 arc seconds
7.8% illumination
Distance from Earth 30,154,150 miles (48,528,401 km)
8:57 AM CDT June 12, 2012 (13:57 UT)
Angular diameter 56.46 arc seconds
1.6% illumination
Distance from Earth 27,463,558 miles (44,198,313 km)
7:33 PM CDT June 5, 2012 (00:33 UT June 6, 2012)
Angular diameter 57.78 arc seconds
0.0% illumination, transiting the Sun
Distance from Earth 26,836,379 miles (43,188,966 km)
Projection method with 60mm refractor telescope and 17mm eyepiece

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I haven’t posted much for a few days, so here’s a big “catch-up:”

Above: Venus shines in the predawn sky at 6:46 AM, November 18, 2012. Though you can’t see it in this photo, Saturn, the ringed jewel of the skies, has reappeared from the far side of the Sun and is a bit to the lower left of Venus. Keep watch these next few mornings, as fainter Saturn and brighter Venus will be closer each morning, and on the mornings of November 26 and 27, 2012, the two planets will be in a spectacularly close conjunction. Don’t miss it!

Here’s a Saturn series, similar in format to my Venus phase updates, beginning with this morning and working back through a few of my best Saturn photos. Note how over time Saturn’s rings are “opening up” as viewed from Earth. Unless otherwise noted, these photos are with the 8″ reflector telescope, 17mm eyepiece, and 2x Barlow:

7:01 AM CST November 20, 2012 (13:01 UT)
Angular diameter 15.49 arc seconds
Distance from Earth 992,918,000 miles (1,598,000,000 km)
11:42 PM CDT June 7, 2012 (04:42 UT June 8, 2012)
Angular diameter 18.15 arc seconds
Distance from Earth 847,415,000 miles (1,363,782,000 km)
4:38 AM CDT April 12, 2012 (09:38 UT)
Angular diameter 18.97 arc seconds
Distance from Earth 810,707,000 miles (1,304,706,000 km)
6:13 AM CST January 8, 2012 (12:13 UT)
Angular diameter 16.82 arc seconds
Distance from Earth 913,348,000 miles (1,471,501,000 km)
25mm eyepiece with 2x Barlow, scaled to match the others
3:23 AM CDT April 14, 2011 (08:23 UT)
Angular diameter 18.97 arc seconds
Distance from Earth 810,570,000 miles (1,304,487,000 km)

One treat of our current predawn sky this November is the Venus-Saturn show in the Southeast counterbalanced with bright Jupiter in the Northeast. Here’s Jupiter, gleaming far beyond the wires in my backyard, at 6:50 AM, November 18, 2012:

And here are the giant planet and the four Galilean moons. From upper left to lower right: Europa, Io, Ganymede, Jupiter, Callisto:

6:57 AM CST November 18, 2012 (12:57 UT). 8″ reflector telescope, 25mm eyepiece, 2x Barlow.

Speaking of Venus, it’s now heading towards the far side of the Sun from us, though it still is a bright, resplendent sight before dawn:

12:05 PM CST, November 19, 2012 (18:05 UT)
Angular diameter 12.25 arc seconds
85.6% illumination
Distance from Earth 126,593,857 miles (203,733,064 km)
1:12 PM CDT, October 12, 2012 (18:12 UT)
Angular diameter 14.69 arc seconds
74.6% illumination
Distance from Earth 105,565,517 miles (169,891,262 km)
2:00 PM CDT, September 21, 2012 (19:00 UT)
Angular diameter 16.83 arc seconds
67.3% illumination
Distance from Earth 92,101,088 miles (148,222,333 km)
8:26 AM CDT, September 10, 2012 (13:26 UT)
Angular diameter 18.36 arc seconds
62.7% illumination
Distance from Earth 84,452,528 miles (135,913,169 km)
10:17 AM CDT, September 4, 2012 (15:17 UT)
Angular diameter 19.31 arc seconds
60.1% illumination
Distance from Earth 80,311,754 miles (129,249,240 km)
1:15 PM CDT, August 21, 2012 (18:15 UT)
Angular diameter 22.02 arc seconds
53.5% illumination
Distance from Earth 70,401,199 miles (113,299,747 km)
7:36 AM CDT, August 13 2012 (12:36 UT)
Angular diameter 24.07 arc seconds
49.1% illumination
Distance from Earth 64,429,600 miles (103,689,390 km)
1:39 PM CDT, August 6, 2012 (18:39 UT)
Angular diameter 26.05 arc seconds
45.2% illumination
Distance from Earth 59,516,628 miles (95,782,727 km)
8:52 AM CDT July 30, 2012 (13:52 UT)
Angular diameter 28.56 arc seconds
40.6% illumination
Distance from Earth 54,298,771 miles (87,385,401 km)
5:49 AM CDT July 22, 2012 (10:49 UT)
Angular diameter 31.96 arc seconds
34.9% illumination
Distance from Earth 48,512,519 miles (78,073,332 km)
9:18 AM CDT July 13, 2012 (14:18 UT)
Angular diameter 36.52 arc seconds
27.9% illumination
Distance from Earth 42,450,876 miles (68,318,063 km)
11:56 AM CDT July 3, 2012 (16:56 UT)
Angular diameter 42.79 arc seconds
19.0% illumination
Distance from Earth 36,238,688 miles (58,320,514 km)
11:21 AM CDT June 27, 2012 (16:21 UT)
Angular diameter 47.07 arc seconds
13.4% illumination
Distance from Earth 32,940,927 miles (53,013,283 km)
8:38 AM CDT June 21, 2012 (13:38 UT)
Angular diameter 51.42 arc seconds
7.8% illumination
Distance from Earth 30,154,150 miles (48,528,401 km)
8:57 AM CDT June 12, 2012 (13:57 UT)
Angular diameter 56.46 arc seconds
1.6% illumination
Distance from Earth 27,463,558 miles (44,198,313 km)
7:33 PM CDT June 5, 2012 (00:33 UT June 6, 2012)
Angular diameter 57.78 arc seconds
0.0% illumination, transiting the Sun
Distance from Earth 26,836,379 miles (43,188,966 km)
Projection method with 60mm refractor telescope and 17mm eyepiece

Not to be outdone, here’s the waxing crescent Moon at 6:38 PM CST November 18, 2012 (00:38 UT November 19, 2012), 8″ reflector telescope with 25mm eyepiece. Note that once again the Sun has risen on Mickey Mouse:

All with LG VX8360 cell phone camera. Click to enlarge.

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When the Moon passes close (in our sky) to a bright “landmark” such as a planet or bright star, it makes it easier to see that it moves about one lunar diameter per hour eastward in its orbit, so you’ll see in this series of photos that it starts to the lower right of Jupiter, and ends up to the lower left:


5:22 AM CDT September 8, 2012 (10:22 UT). You’ll see that light balance is a challenge to my low-budget cell phone astrophotography when the sky is dark and the Moon is illuminated 50% or less, but the balance improves as the sky lightens, and lunar detail appears.


The Moon at 5:35 AM.


5:39 AM.


5:52 AM.


6:17 AM.


6:26 AM.


A closeup of Jupiter and the four Galilean Moons during the conjunction, at 6:29 AM CDT (11:29 UT). From left to right: Europa, Ganymede, Io, Jupiter, Callisto. 8″ reflector telescope with 25mm eyepiece and 2x Barlow.


6:35 AM.


6:36 AM.


6:53 AM.


7:02 AM.

Jupiter/Moon photos with 60mm refractor telescope and 25mm eyepiece. Moon photos with 8″ reflector telescope and 25mm eyepiece. All with LG VX8360 cell phone camera. Click to enlarge.

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Not only is it great fun to watch Jupiter’s four Galilean Moons as they orbit, it’s also a reenactment of one of the most pivotal discoveries of early modern astronomy. Along with the phases of Venus, they were one of the first bits of unassailable evidence that not all celestial objects had Earth-centered orbits. At times only a few minutes can make a noticeable difference in the configuration of these four large, bright moons, and that was the case yesterday morning. In the following series of photos, one can see conspicuous changes in the span of only 36 minutes, especially with Io and Ganymede to Jupiter’s right:

6:00 AM CDT September 4, 2012 (11:00 UT). I oriented these photos with north at the top, which I usually don’t do with planetary photos. From left to right we see Callisto, Europa, Jupiter, then Ganymede (lower) and Io (upper). In the next few photos you see Ganymede orbiting to the right, as it has just passed between Earth and Jupiter (it had transited Jupiter six hours earlier), whereas speedy Io was orbiting to the left, and was eclipsed and then occulted by Jupiter three hours afterward:


6:19 AM CDT (11:19 UT)


6:23 AM CDT (11:23 UT)


6:31 AM CDT (11:31 UT)


6:36 AM CDT (11:36 UT). You may also have noticed the transition from deep twilight to a bright sky. Sunrise at my location was eleven minutes after the last photo. By the way, Jupiter’s distance from Earth at the time of this photo series was about 462,230,000 miles, and getting closer.

Venus and Jupiter continue to dominate the predawn sky, even more so than this photo suggests. Looking southwest, with Venus to the lower left and Jupiter in the upper right, 6:10 AM CDT, September 2, 2012:

A visual treat is coming up in the predawn sky on Saturday, September 8, especially for North American observers, as the Last Quarter Moon will be in close conjunction with Jupiter.

As I mentioned, the changing phases and apparent size of Venus were also a pivotal discovery of early telescopic astronomy, momentous indeed in the history of scientific thought. The great ancient astronomer Ptolemy had correctly predicted that Venus would appear as a crescent, but incorrectly supposed that it would always be a crescent, since he believed that Venus was always between the Earth and the Sun. But Venus appears largest during its crescent phase and its apparent size wanes as it waxes towards the full phase, which is exactly what we would expect if Venus’ motion is Sun-centered rather than Earth-centered.

Venus has attained the gibbous phase, and soon will be as far from us as the Earth is from the Sun:

10:17 AM CDT, September 4, 2012 (15:17 UT)
Angular diameter 19.31 arc seconds
60.1% illumination
Distance from Earth 80,311,754 miles (129,249,240 km)
1:15 PM CDT, August 21, 2012 (18:15 UT)
Angular diameter 22.02 arc seconds
53.5% illumination
Distance from Earth 70,401,199 miles (113,299,747 km)
7:36 AM CDT, August 13 2012 (12:36 UT)
Angular diameter 24.07 arc seconds
49.1% illumination
Distance from Earth 64,429,600 miles (103,689,390 km)
1:39 PM CDT, August 6, 2012 (18:39 UT)
Angular diameter 26.05 arc seconds
45.2% illumination
Distance from Earth 59,516,628 miles (95,782,727 km)
8:52 AM CDT July 30, 2012 (13:52 UT)
Angular diameter 28.56 arc seconds
40.6% illumination
Distance from Earth 54,298,771 miles (87,385,401 km)
5:49 AM CDT July 22, 2012 (10:49 UT)
Angular diameter 31.96 arc seconds
34.9% illumination
Distance from Earth 48,512,519 miles (78,073,332 km)
9:18 AM CDT July 13, 2012 (14:18 UT)
Angular diameter 36.52 arc seconds
27.9% illumination
Distance from Earth 42,450,876 miles (68,318,063 km)
11:56 AM CDT July 3, 2012 (16:56 UT)
Angular diameter 42.79 arc seconds
19.0% illumination
Distance from Earth 36,238,688 miles (58,320,514 km)
11:21 AM CDT June 27, 2012 (16:21 UT)
Angular diameter 47.07 arc seconds
13.4% illumination
Distance from Earth 32,940,927 miles (53,013,283 km)
8:38 AM CDT June 21, 2012 (13:38 UT)
Angular diameter 51.42 arc seconds
7.8% illumination
Distance from Earth 30,154,150 miles (48,528,401 km)
8:57 AM CDT June 12, 2012 (13:57 UT)
Angular diameter 56.46 arc seconds
1.6% illumination
Distance from Earth 27,463,558 miles (44,198,313 km)
7:33 PM CDT June 5, 2012 (00:33 UT June 6, 2012)
Angular diameter 57.78 arc seconds
0.0% illumination, transiting the Sun
Distance from Earth 26,836,379 miles (43,188,966 km)
Projection method with 60mm refractor telescope and 17mm eyepiece

Unless otherwise noted, 8″ reflector telescope, 25mm eyepiece with 2x Barlow, LG VX8360 cell phone camera.

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Venus and Jupiter continue to linger brilliantly in the predawn sky. Here they are at 5:27 this morning. Jupiter is fainter to the upper right of Venus, towards the tree:

I never tire of watching Jupiter’s four Galilean Moons as they orbit. It’s the easiest way to see “live” what a planetary system looks like from the outside:

Above: 5:17 AM CDT July 23, 2012 (10:17 UT). L-R: Callisto, Ganymede, Io, Jupiter, Europa.
Below: 5:33 AM CDT August 1, 2012 (10:33 UT). L-R: Ganymede, Io, Europa, Jupiter, Callisto.
Both with 8″ reflector telescope, 25mm eyepiece, and 2x Barlow.

My lunar photography has been a bit sparse as of late, but here are three from the last half of July:

Above: Waning crescent Moon at 5:32 AM CDT July 16, 2012 (10:32 UT).
Below: Waxing crescent Moon at 9:25 PM CDT July 21, 2012 (02:25 UT 7-22-12). Both with 8″ reflector telescope and 25mm eyepiece.


Waxing gibbous Moon at 2:17 AM CDT July 30, 2012 (07:17 UT), 60mm refractor telescope with 17mm eyepiece.

Venus is now just over twice as far away from Earth as it was at the time of the transit:

8:52 AM CDT July 30, 2012 (13:52 UT)
Angular diameter 28.56 arc seconds
40.6% illumination
Distance from Earth 54,298,771 miles (87,385,401 km)
5:49 AM CDT July 22, 2012 (10:49 UT)
Angular diameter 31.96 arc seconds
34.9% illumination
Distance from Earth 48,512,519 miles (78,073,332 km)
9:18 AM CDT July 13, 2012 (14:18 UT)
Angular diameter 36.52 arc seconds
27.9% illumination
Distance from Earth 42,450,876 miles (68,318,063 km)
11:56 AM CDT July 3, 2012 (16:56 UT)
Angular diameter 42.79 arc seconds
19.0% illumination
Distance from Earth 36,238,688 miles (58,320,514 km)
11:21 AM CDT June 27, 2012 (16:21 UT)
Angular diameter 47.07 arc seconds
13.4% illumination
Distance from Earth 32,940,927 miles (53,013,283 km)
8:38 AM CDT June 21, 2012 (13:38 UT)
Angular diameter 51.42 arc seconds
7.8% illumination
Distance from Earth 30,154,150 miles (48,528,401 km)
8:57 AM CDT June 12, 2012 (13:57 UT)
Angular diameter 56.46 arc seconds
1.6% illumination
Distance from Earth 27,463,558 miles (44,198,313 km)
7:33 PM CDT June 5, 2012 (00:33 UT June 6, 2012)
Angular diameter 57.78 arc seconds
0.0% illumination, transiting the Sun
Distance from Earth 26,836,379 miles (43,188,966 km)
Projection method with 60mm refractor telescope and 17mm eyepiece

Unless otherwise noted, 8″ reflector telescope, 25mm eyepiece with 2x Barlow, LG VX8360 cell phone camera.

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The Moon, Jupiter, and Venus form a graceful arc before dawn at 5:05 AM CDT July 14, 2012. On the morning of July 15th, the Moon will be close in between Jupiter and Venus. IMPORTANT: If you’re viewing from parts of Asia, Europe, or North Africa, you may witness an occultation of Jupiter by the Moon on the morning of the 15th. Details and map here:

15 July 2012 Occultation of Jupiter


Above, from left to right: Callisto, Ganymede, Jupiter, Europa. Io was transiting Jupiter at the time. 5:06 AM CDT July 14, 2012 (10:06 UT).


Above: Waning crescent Moon at 5:28 AM CDT July 14, 2012 (10:28 UT). 8″ reflector telescope with 25mm eyepiece.
Below: Closeups with added 2x Barlow:

5:17 AM.

5:24 AM.

5:16 AM.

All with LG VX8360 cell phone camera. Click to enlarge.

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I hadn’t taken a photo of Jupiter with the four Galilean Moons since last March. I never get tired of viewing this ever-changing “mini solar system.” Above, from left to right: Callisto, Io, Europa, Jupiter, Ganymede. Above & to the left of Jupiter, a star in the background is trying to pose as a fifth Galilean Moon (or perhaps the moons are trying to pose as stars!). 8″ reflector telescope with 25mm eyepiece and 2x Barlow, which makes it photo on the same scale as the lunar closeups below.

5:19 AM CDT July 10, 2012 (10:19 UT), 8″ homebuilt reflector telescope and 25mm eyepiece.

Photos below with 25mm eyepiece and 2x Barlow:
The north end of the Moon at 5:14 AM CDT, including Mare Imbrium (the “Sea of Showers”), and crater Plato prominent in upper center, the Alpine Valley to its lower right:

The south end of the Moon at 5:16 AM CDT, with Clavius and its inner craters even more clear than yesterday, as the afternoon shadows lengthen:


Venus and Jupiter shining in the brightening predawn sky, at 4:46 AM above, and 4:57 AM below:

All with LG VX8360 cell phone camera. Click to enlarge, and don’t let me forget to bring the mosquito repellant next time!!!

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