1 February 2011: It is a quiet and peaceful night. Rated sparkle stars flashes into the velvety darkness overhead as a remote plain in the background on the horizon. You could hear almost a PIN fall.
That is, until the flare.
High overhead, out of the darkness, a bright light surges in sight. For 5-10 seconds it exceeds weak shadow at the feet of imitation of a supernova, the brightest stars in the sky, perhaps casting. The silence is broken shouts excitedly by your own.
That could happen to you?
"It could, if you happen outside, if NanoSail D of flies" Dean Alhorn says the Marshall Space Flight Center in Huntsville, al. "could produce the spacecraft of this type of display from time to time, we think when sunlight shimmer the reflective fabric of its solar sail off."
On January 21, NanoSail-D 10 m2 sails unfurled 650 km above the surface of the Earth, always the first solar sail to our planets orbit. For the next few months he will skim it up in the atmosphere, slowly descending in a test 'pull sail as a means of space junk'. If the probe everything as planned, will be in April or may 2011, such as a Meteor harmless more than 100 km high decay dispersing.
In the meantime, sky should watchers warning to the torch.
Many people have already seen Iridium Flares--brilliant flashes of sunlight glittered off the flat antennas, Iridium communications satellites. Some Iridium flares are so bright, they can be seen in broad daylight. NanoSail-D could be even brighter.
"The area of our sail six times greater than that of a single Iridium antenna," stresses Alhorn. "Plus, we are closer to the Earth." "Much brighter Flash brings all that to one."
NanoSail-D on the Earth closer, it could theoretically produce light flashes 10 to 100 times (2.5 to 5 astronomical magnitudes) brighter than the planet Venus. This is the kind of thing that you can see, even by the city lights.
Between flares, the sail is however quite dim. international recognised satellite navigation expert Ted Molczan describes what he and others have seen:
"NanoSail-D may be to see a sophisticated object, but by no means impossible." At the least, it is invisible, but the brightest in large binoculars, it is easily seen with the un-aided eye. The large differences in brightness is due to its shape; It is a large, highly reflective thin sheet material. Edge-on, it is weak, but seen face-on at a low sun angle, it can rival of the brightest stars. "
NanoSail-D flyby can predict in several places on the Web are found: sky above, Spaceweather.com and Calsky among others. These sites are you when the sail will increase overhead-- but not it is as a flare. The orientation of the sail is known not just enough for it.
"Because it is impossible to predict when NanoSail-D will be bright, observers can increase their chances of success by watching over a period of at least a few minutes," says Molczan. "A plot of predicted path on a Star chart, with notes of the time at intervals of one minute or so, helps the Viewer to the satellite focus approximate position moves on the sky." "Observe with the naked eye or binoculars with a wide field of view, such as 7x50s."
The brightest flares are likely to occur when the probe in the vicinity is the horizon. Former NanoSail-D principal investigator mark Whorton (previously at NASA,) now at Teledyne explains, why:
"Early in the mission NanoSail-D will be tumbling so that it doesn't really matter where it is in heaven." Flashes can occur almost anywhere, on his way. But later in the mission aerodynamically stabilized be is: the flat surface of the sail is forward, much like the sail a terrestrial sailing vessel. That means, you will see it edge on (Dim) when it directly overhead and face up (light) when it is closer to the horizon. "
So you check the predictions out there to go and take a look. Alhorn says, "some value could you cry over see."
BONUS: Monitor to promote the sail to amateur astronomers, have NASA and Spaceweather.com, to stage a photo competition together. From $100 to $500 cash prizes are offered for best photos of NanoSail-D between now and the time, the sail is divided, submitted. High resolution telescope images of the spacecraft transmits, wide angle shots of NanoSail D height are overhead and lucky shots of flares fast all allowed. Visit nanosail.org for complete details.
Author: Dr. Tony Phillips | Credit: Science@NASA
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