The Sky is Waiting.
Search AstroGuyz
Custom Search
Advertise on Astroguyz!
|
|
|
 |
|
Pictured is a Delta IV rocket launch from Cape Canaveral on November 21st, 2010. The image is a 20 second exposure taken at dusk, shot from about 100 miles west of the launch site. The launch placed a classified payload in orbit for the United States Air Force.
Difficult but not impossible to catch against the dawn or dusk sky, spotting an extreme crescent moon can be a challenge. The slender crescent pictured was shot 30 minutes before sunrise when the Moon was less than 20 hours away from New. A true feat of visual athletics to catch, a good pair of binoculars or a well aimed wide field telescopic view can help with the hunt.
The Sun is our nearest star, and goes through an 11-year cycle of activity. This image was taken via a properly filtered telescope, and shows the Sun as it appeared during its last maximum peak in 2003. This was during solar cycle #23, a period during which the Sun hurled several large flares Earthward. The next solar cycle is due to peak around 2013-14.
Located in the belt of the constellation Orion, Messier 42, also known as the Orion Nebula is one of the finest deep sky objects in the northern hemisphere sky. Just visible as a faint smudge to the naked eye on a clear dark night, the Orion Nebula is a sure star party favorite, as it shows tendrils of gas contrasted with bright stars. M42 is a large stellar nursery, a star forming region about 1,000 light years distant.
Orbiting the planet in Low Earth Orbit (LEO) every 90 minutes, many people fail to realize that you can see the International Space Station (ISS) from most of the planet on a near-weekly basis. In fact, the ISS has been known to make up to four visible passes over the same location in one night. The image pictured is from the Fourth of July, 2011 and is a 20 second exposure of a bright ISS pass.
Next to the Sun, the two brightest objects in the sky are the Moon and the planet Venus. In fact, when Venus is favorably placed next to the Moon, it might just be possible to spot the two in the daytime. Another intriguing effect known as earthshine or ashen light is also seen in the image on the night side of the Moon; this is caused by sunlight reflected back off of the Earth towards our only satellite.
A mosaic of three images taken during the total lunar eclipse of December 21st, 2010. The eclipse occurred the same day as the winter solstice. The curve and size of the Earth’s shadow is apparent in the image.
The Algonquin Indians had names for each of the seasonal Full Moons, many of which survive today. The Full Snow Moon pictured occurs in the month of December, when the first large winter storms coat the ground with snow. This Full Moon also tends to fall near the Winter Solstice, and thus rides high in the nightly sky opposite to the Sun on long winter nights.
Every rocket launch is unique, but twilight shuttle launches where by far the most impressive. The image pictured was of the April 5th, 2010 launch of Space Shuttle Discovery from the Kennedy Space Center at dawn. The exhaust plume caught the rising Sun overhead just right, and numerous noctilucent clouds persisted right up until sunrise. Unfortunately, space shuttle launches are now relegated to the pages of history.
Astro-Event of the Week: 05.18.09: Spot a Hubble Classic!
A close up shot of one of the pillars. (Credit: APOD/NASA/Hubble Hertitage Team/STS.I/AURA).
As all eyes are now in orbit following the intrepid crew of the shuttle Atlantis as they carry out the final repairs to the Hubble Space Telescope, now is a good time to track down one of its classic targets. One of Hubble’s most enduring photographs is that of the Eagle Nebula. Our challenge to you is to try and spy this illusive nebula. A broad, emission nebula in the constellation Serpens, this also has the multiple designations of M16 in the messier catalog and NGC 6611. Many folks, even seasoned amateurs, have never viewed this extraordinary object. It is embedded in a rich star field along the galactic plane, and will begin riding high to the south around mid-summer evenings for northern hemisphere observers. Currently, it rises in the east around midnight, so early mornings are your best bet. As the Moon wanes out of the morning sky, an astronomers’ fancy frequently turns towards deep sky objects such as M16. And the darker, less light polluted your site, the better! M16 is a fine target for apertures of 6″ or greater; also allow for a generous amount of field of view to see the surrounding nebulosity. Try this target with an assortment of filters, and long exposure photography will bring out more detail. Don’t expect your view to equal Hubble’s: at a distance of 7,000 light years, it’s a churning cradle of active stellar birth. Some debate has ensued as of late as to whether these “pillars of creation” exist any longer or have since been dissipated. Never the less, the view provides a fascinating snapshot into early star formation! Coordinates for the Eagle Nebula are:
Declination: -13° 49′
Right Ascension: 18Hours 18′ 48″
This week’s Astro-term of the Week is emission nebula. Emission nebulae (plural) are clouds of dust and gas that are being lit from within, like a paper lantern. The diffuse gases associated with these nebulae are becoming ionized, causing them to glow. Some are lit by the death throes of stars, such as the Ring Nebula (M57) in Lyra, others, such as M16 or the Pleiades, are being illuminated by new, upstart stars. Compare these to dusky Bok globules or the dark lanes mottling the summer Milky Way. Incidentally, the surface brightness of emission nebula can be somewhat misleading. For example, the magnitude of the Eagle Nebula is usually given as +6, about the limit of the naked eye under dark skies. Keep in mind, however, that this is spread out over a surface area about 7 arc minutes across. Needless to say, the Eagle nebula is a tougher target visually than a +6 magnitude star, but as with much of astronomy, part of the essence of “coolness” is knowledge of what you’re looking at. Good luck and dark skies!