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Earth is at solstice on Friday June 21. The Full Moon is Sunday June 23. At this time it will be closer to Earth than any other time this year (a so called "Super Moon"). Mars rises in the morning twilight. Venus and Mercury are close t...
Earth is at solstice on Friday June 21. The Full Moon is Sunday June 23. At this time it will be closer to Earth than any other time this year (a so called "Super Moon"). Mars rises in the morning twilight. Venus and Mercury are close together in the evening twilight. Saturn is high in the evening skies. The Moon occults the bright star alpha Librae 2 on the 20th.The Full Moon is Sunday June 23. At this time the Moon will be at perigee, when it is closest to the Earth. This is the closest perigee for 2013 at 356989 km. A full Moon at perigee has been called a "SuperMoon", this is not an astronomical term, but an astrological one. While the Moon is close, it will have no real effect (or be distinguishable without a telescope and a good memory).The Moon at Perigee and apogee as seen through a telescope. With the unaided eye, the Moon only appears half a finger-width wide, so the difference is much harder to see. This months Full Moon could appear up to 14% bigger and 30% brighter in the sky than average. But will you actually notice if it is different to the last Full Moon? The limit of distances that someone with good vision can distinguish between is 1 minute of arc (about the width of a human hair). So, for the vast majority of people any difference smaller than 1 minute of arc cannot be seen.The Moon this Full Moon will be 33'57" wide (just a touch over half a degree, around half a finger-width wide), last months Full Moon (358374 km) was 33'47" wide. Without a telescope and careful astrophotography you will not notice the difference.If you can wait until January the 16th 2014, when the Full Moon is at Apogee, then it’s diameter will be 29'32" , and you could notice a difference if you have a good memory, but it won’t be spectacular. The illustration above is from November 28, 2012, when the Moon was at apogee and 29'33" wide when it was 406364 km from EarthHowever, while the "SuperMoon" will not be spectacular, it will be a good photo opportunity, if you have a decent zoom on your camera, taking a photo of the Moon on June 23 and then again on January 16 2014 you will see a decent difference (you need to use exactly the same zoom enlargement, see Inconstant Moon for instructions).The evening sky facing east in Sydney on June 20 at 5:05 pm AEST showing the waxing Moon just about to cover alpha2 Librae. (similar views will be seen from other locations at a similar local time eg 5:08 AEST Canberra). The inset shows a telescopic view of the Moon at 5:05 pm AEST, with alpha2 Librae about to go behind the Moon.The waxing Moon passes in front of the bright alpha2 Librae in the constellation of Libra on the evening of June 20. Alpha2 Librae is a bright white star readily visible to the unaided eye (magnitude 2.8). The occultation will be seen from eastern Australia and South Australia. Everywhere else will see a nice, close approach.From Adelaide the star reappears from the bright limb at 17:23 ACST. From Brisbane the star reappears at 18:05 AEST (the disappearance behind the dark limb is too deep in the twilight to be really seen).From Canberra the star disappears behind the dark limb of the Moon at 17:08 AEST, and reappears at 18:08 AEST. From Hobart the star disappears behind the dark limb of the Moon at 17:28 AEST, and reappears at 18:07 AEST.From Melbourne the star disappears behind the dark limb of the Moon at 17:13 AEST, and reappears at 18:03 AEST. From Sydney the star disappears behind the dark limb of the Moon at 17:06 AEST, and reappears at 18:10 AEST.With the Moon not far from Full, this event is really best seen with binoculars or a small telescope (especially for the reappearance of the star on the bright limb of the Moon). If you have a tripod or other stand for your binoculars, it will be much easier to observe. Set up about half an hour before the occultation to watch the star dissapear (so you are not mucking around with equipment at the last moment). Evening sky looking west as
about 6 hours ago
I've given the astrophotography and astronomy a little bit of a break for a while. Work and family commitments have kept me away from the dark skies for quite some time. I'm off to Australia son and hope to take some wide field shots dow...
I've given the astrophotography and astronomy a little bit of a break for a while. Work and family commitments have kept me away from the dark skies for quite some time. I'm off to Australia son and hope to take some wide field shots down there, so will hopefully have some interesting shots to share when I get back.In the meantime, check out my new photography site here. I've been spending more time shooting motorsports and photojournalism.this past year, picking up the odd official gig here and there.Have a safe summer, and more astro images to come soon!Cheers,Phil
about 10 hours ago
Having followed the activities of a small army of freelance space imagers that lurk in various places on the internet for about 10 years now — it is truly unusual for me to come across images that I know I have not seen before. Michael B...
Having followed the activities of a small army of freelance space imagers that lurk in various places on the internet for about 10 years now — it is truly unusual for me to come across images that I know I have not seen before. Michael Benson’s exhibit titled, “Planetfall” at the American Association for the Advancement of Science offers [...]
about 10 hours ago
<p><a href="http://antwrp.gsfc.nasa.gov/apod/ap130617.html"><img src="http://antwrp.gsfc.nasa.gov/apod/calendar/S_130617.jpg" align="left" alt="What creates these long and nearly straight grooves on Mars?" border="0" /></...
<p><a href="http://antwrp.gsfc.nasa.gov/apod/ap130617.html"><img src="http://antwrp.gsfc.nasa.gov/apod/calendar/S_130617.jpg" align="left" alt="What creates these long and nearly straight grooves on Mars?" border="0" /></a> What creates these long and nearly straight grooves on Mars?</p><br clear="all"/>
about 11 hours ago
Bokeh. There’s that word again. It’s one of the most obsessed-over words in photography, from how to pronounce it to how to “make it.” It often seems as if too many photographers — primarily newer practitioners — have placed ...
Bokeh. There’s that word again. It’s one of the most obsessed-over words in photography, from how to pronounce it to how to “make it.” It often seems as if too many photographers — primarily newer practitioners — have placed a disproportionate premium on the concept of bokeh without fully understanding what it is. Bokeh originates from the Japanese word meaning “blur” or “haze.” As it relates to photography, bokeh refers to the aesthetic quality of a photograph’s out of focus areas, including the specular highlights that most easily reveal a lens’ aperture shape (often rendered as the bright circles that people so love); it does not refer to the blur caused by subject or camera movement. Bokeh is not a quantitative concept; unlike lens aperture or shutter speed, bokeh has no associated system of measurement. What matters is the quality of the blur, not the amount. Accordingly, bokeh is a rather subjective idea; one person’s opinion of “good” bokeh may not fall in line with another person’s opinion. ? The Drongo Love ? Happy Valentine’s Day ? by VinothChandar, on Flickr As you may have gathered from the brief definition above, bokeh is a feature of a photograph, not necessarily a feature of a lens. Lenses do, however, possess certain design characteristics that affect how the bokeh is rendered in photo. There are scenes that just sort of lend themselves to producing smooth, creamy bokeh even with not-so-great lenses, while other scenes — such as those with harsh lighting or lots of specular highlights — present a much greater challenge. It is in situations like these where the quality of the lens will have a more noticeable impact on the quality of the bokeh, but there is no such thing as a perfect bokeh lens. Which brings us back to the point of subjectivity. You probably have your own ideas of what constitutes good bokeh, so it is important to understand how the lens you are using renders blur. It’s no different than knowing at which apertures or focal lengths your lens vignettes; some photographers like vignetting and use it to great artistic effect. Others hate it. There’s no right or wrong here; lenses are tools that you have to learn and master in order to make the most of them. Hu Jieqiong by Jonathan Kos-Read, on Flickr The lens, of course, isn’t the only thing that plays a role in creating bokeh. What follows are some tips on how to bring together a number of factors that will help you achieve the “best” possible bokeh in your shots. Use a large aperture. To be more specific, use the largest aperture (smallest f-number) available on your lens. A large aperture decreases depth of field, dramatically isolating focus on a narrow part of your subject. Everything surrounding this focal point will be blurred, thus creating bokeh. Use a fast lens. Lens speed refers to the maximum aperture (smallest f-number) of a lens; the larger the maximum aperture, the faster the lens is considered to be (f/1.8 is faster than f/4), the more light you can let in, the more you can decrease depth of field, the more likely your image is to exhibit smooth, pleasing to the eye out of focus areas. Go long. Zoom lenses are often criticized for not being up to par with the image quality of prime lenses (though there are some notable exceptions), but if you have a zoom lens, use it to your advantage. Zooming in on your subject will separate it from the rest of the scene and, depending on your lens, should leave you with beautiful bokeh. Move in. The closer you get to your subject, the blurrier the background will be. Every lens has a minimum focusing distance (MFD); this is simply a measure of how close you can be to your subject and still lock focus. The concept of getting in close to your subject while blurring the background is maximized in macro lenses. Any lens can be used this way, however, though to considerably less dramatic effect. And it’s probably not advisable for most portrait work. Blades of glory.
about 15 hours ago
The Full Moon is Sunday June 23 in Australia. At this time the Moon will be at perigee, when it is closest to the Earth. This is the closest perigee for 2013 at 356989 km. A full Moon at perigee has been called a "Super Moon", this is ...
The Full Moon is Sunday June 23 in Australia. At this time the Moon will be at perigee, when it is closest to the Earth. This is the closest perigee for 2013 at 356989 km. A full Moon at perigee has been called a "Super Moon", this is not an astronomical term, but an astrological one (see also here). While the Moon is close, it will have no real effect (or be distinguishable without a telescope and a good memory).The Moon at Perigee and apogee as seen through a telescope. With the unaided eye, the Moon only appears half a finger-width wide, so the difference is much harder to see. This months Full Moon could appear up to 14% bigger and 30% brighter in the sky than average. But will you actually notice if it is different to the last Full Moon?The limit of distances that someone with good vision can distinguish between is 1 minute of arc (about the width of a human hair). So, for the vast majority of people any difference smaller than 1 minute of arc cannot be seen.The Moon this Full Moon will be 33'57" wide (just a touch over half a degree, around half a finger-width wide), last months Full Moon (358374 km) was 33'47" wide. Without a telescope and careful astrophotography you will not notice the difference. For a list of full/new Moons and the dates of apogee/perigee see here.If you can wait until January the 16th 2014, when the Full Moon is at Apogee, then it’s diameter will be 29'32" , and you could notice a difference if you have a good memory, but it won’t be spectacular. The illustration above is from November 28, 2012, when the Moon was at apogee and 29'33" wide when it was 406364 km from Earth.However, while the "SuperMoon" will not be spectacular, it is still pretty and will be a good photo opportunity. If you have a decent zoom on your camera, after taking a photo of the Moon on June 23 and then again on January 16 2014 you will see a decent difference (you need to use exactly the same zoom enlargement, see Inconstant Moon for instructions).And, no, we will not get earthquakes from the "Super Moon".
about 18 hours ago
Carnival of Space #306 is now up at the Urban Astronomer. There is a Black Hole Bonanza, science outreach in libraries, Martian Streambeds, robotics for space development and more! Clank on over and have a read.
Carnival of Space #306 is now up at the Urban Astronomer. There is a Black Hole Bonanza, science outreach in libraries, Martian Streambeds, robotics for space development and more! Clank on over and have a read.
1 day ago
After images are added to the database they are cataloged to provide metadata. Note that the number of records returned by the link will be less than the number of newly cataloged photographs if some of those cataloged photographs have ...
After images are added to the database they are cataloged to provide metadata. Note that the number of records returned by the link will be less than the number of newly cataloged photographs if some of those cataloged photographs have no digital image available.
1 day ago
Images are added to the database prior to being cataloged for metadata. This makes them available for viewing while the catalog process is in work.
Images are added to the database prior to being cataloged for metadata. This makes them available for viewing while the catalog process is in work.
1 day ago
The evening sky facing east in Sydney on June 20 at 5:05 pm AEST showing the waxing Moon just about to cover alpha2 Librae (Zubenelgenubi). (similar views will be seen from other locations at a similar local time eg 5:08 AEST Canberra). ...
The evening sky facing east in Sydney on June 20 at 5:05 pm AEST showing the waxing Moon just about to cover alpha2 Librae (Zubenelgenubi). (similar views will be seen from other locations at a similar local time eg 5:08 AEST Canberra). The inset shows a telescopic view of the Moon at 5:05 pm AEST, with alpha2 Librae about to go behind the Moon.The waxing Moon passes in front of the bright alpha2 Librae in the constellation of Libra on the evening of June 20. Alpha2 Librae, which rejoices in the name Zubenelgenubi, is a bright white star readily visible to the unaided eye (magnitude 2.8). The occultation will be seen from eastern Australia and South Australia. Everywhere else will see a nice, close approach. Appearance and disappearance times are shown in the table below.CityDisappears Dark LimbReappears Bright LimbAdelaide-17:23 ACSTBrisbane-18:05 AESTCanberra17:08 AEST18:08 AESTDarwin-1deg at twilightHobart17:28 AEST18:07 AESTMelbourne17:13 AEST18:03 AESTSydney17:06 AEST18:10 AESTPerth-1deg at twilight With the Moon not far from Full (23 June), this event is really best seen with binoculars or a small telescope (especially for the reappearance of the star on the bright limb of the Moon). If you have a tripod or other stand for your binoculars, it will be much easier to observe. Set up about half an hour before the occultation to watch the star dissapear (so you are not mucking around with equipment at the last moment).
1 day ago