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[...] of Mount Mitchell (the highest peak in the Appalachians) our cabin afforded a fine view of the 2012 Geminid meteors. And this was none too soon, as BBC 5 Live called us up that very night for a Skype interview! With [...]
The Sky is Waiting.
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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.
Astro-Event: Of Meteor Showers & Near Earth Asteroids.
Toutatis near Aldebaran on December 19th.
It’s a shooting gallery out there. As the scarred surface of our Moon attests, the inner solar system is routinely criss-crossed by comets and asteroids that would do our precious niche of the universe harm.
This week, we’re in for several fine examples of debris in our neighborhood; a dependable meteor shower in the form of the Geminids, a possible “wild-card” meteor outburst, and a chance to spot one of the most well known and studied Earth-crossing asteroids.
The Geminid meteor shower peaks this week with a Zenithal Hourly Rate (ZHR, or the number on meteors you can expect to see under ideal conditions) of 120. This is centered on December 13th at 23:30 UTC, which would place Asia and Indian Ocean longitudes in an optimal position for viewing early on the morning of the 14th. Of course, its always worth watching for Geminids worldwide a few mornings on either side of the target date. This year is particularly favorable, as the Moon also reaches New earlier on the 13th and is thus safely out of view, Though meteors may seem brilliant, they’re actually tiny dust-sized grains of cometary debris strewn along a comet’s orbit, a sort of calling card saying “a comet was here.” Where the Earth intersects that trail, we get an annual meteor shower, and these streams evolve and fade or intensify over time. In the case of the Geminids, there’s an especially strange twist, in that the source is an asteroid named 3200 Phaethon. Is Phaethon an inactive cometary nucleus, or some strange asteroid/comet hybrid? Thoughts to ponder this Geminid season… the Geminids radiant lies very close to the bright star Castor at its peak.
There’s also another meteor shower worth watching for this week; the “46P-ids” may come into play. Predictions are for a respectable ZHR of 10-30 meteors with multiple peaks from December 10-14th. The suspected shower draws its tentative name from comet 46P/Wirtanen. The radiant lies at declination +3.6° right ascention 357° very near the circlet of Pisces… could a new shower dubbed the “Piscids” be in the works? What ever the case, keep an eye out for all things meteoritic and tweet those sightings to #Meteorwatch!
The path of 4179 Toutatis from December 10th to the 26th. (Graphics created by the author in Starry Night).
This week also sees the chance to spot a bright and nearby asteroid. 4179 Toutatis has been pinged with radar at Goldstone on previous passes and is in our solar neighborhood again this week. 4179 Toutatis is in a 3:1 resonance with Jupiter and a 1:4 resonance with Earth in a 4 year orbit that just crosses inside our own. Although the chances of a collision with Earth in the near future (i.e. for the next few centuries) are extremely low, 4.5 kilometer wide (on its longest axis) 4179 Toutatis makes for a fascinating study of near Earth asteroids, should we ever have to move one out of the way. The Chinese spacecraft Chang’e-2 is scheduled to pass within a few hundred kilometers of 4179 Toutatis on December 13th.
For backyard observers, 4179 Toutatis passes within two degrees of the bright star Aldebaran on the night of Dec 19 at about 9th magnitude. Its closest approach is on December 12th at 18 times the distance of the Moon or 4.5 million miles, (0.0465 Astronomical Units) and the asteroid will shine at around 10th-9th magnitude in the constellation Cetus and Pisces. Apparent speed at closest approach will be about 1 degree every 3 hours or 1’ arc minute every 3 minutes, noticeable after a few minutes of observation.
4179 Toutatis made its last close approach on November 9th, 2008 (0.05AU), and its Next close passage isn’t until November 5th, 2069 (0.019AU). One of the closest passes in recent times was on September 29th, 2004 (0.01AU) when we observed it as a slowly gliding “star” with moment visible after only a few seconds of observation… be sure to watch for 4179 Toutatis if you can!