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[...] Pioneers were also at the center of controversy for a time due to what became known as the “Pioneer Anomaly,” an apparent discrepancy of the spacecraft’s predicted versus actual position in space. While [...]
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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.
28.04.11: Can You Say “Pioneer Non-nomaly?”
Pioneer; Looking Back. (Credit: Artists conception NASA/JPL).
Every advocate of alternative physics’ favorite spacecraft anomaly has been finally laid to rest recently. In 1972 & 1973 The Pioneer 10 and 11 spacecraft were sent on trajectories past Jupiter and Saturn that would take them out of the solar system. Now at a distance of 103 and 83 A.U. moving at 11.5 km per second, these spacecraft fell silent in 2003. Over the years, however, scientists mulling over their positional data had come up with an effect that just wouldn’t go away; dubbed the “Pioneer Anomaly” it seemed that the spacecraft were not quite where they should be. Was an unseen body or medium creating a drag on the Pioneer spacecraft? Some even whispered that Newtonian physics itself was to blame, and that these hallowed laws of gravity and motion were due for a tweaking, the likes of which hadn’t been seen since Einstein. In 2006, Slava Turyshev of the Jet Propulsion Laboratory announced that uneven radiational heating could explain some of the anomaly. Consider the Yarkovsky Effect, where heating and radiation can alter an asteroids course over time. Now, Portuguese physicists have used a method known as Phong shading to model how the diffuse patterns of light and shading work on the twin Pioneer spacecrafts’ paraboloidal antennae. These 2.7 meter dishes are pointed sunward, and slowly radiate propulsive waste heat outward and towards the shaded equipment compartments. These models accurately describe the motions of the Pioneer spacecraft seen before they went silent. No need to trash-talk Newton or Einstein. Physics works, both in our solar system and outside of it, but it probably won’t stop basement crackpots from trying to re-invent what’s already been observed… further platforms will put this model to the test, as the twin Voyager spacecraft are still transmitting, and New Horizons is on an outward journey as well. Pioneer 11 is off in the southern hemisphere constellation Scutum, and Pioneer 10 is headed in the direction of the bright star Aldebaran in the constellation Taurus.