The Sky is Waiting.
(Credit: Eclipse Predictions by Fred Espenak, NASA’s GSFC).
Are you a frustrated astronomer “North of the 60°”? Are you tired of hearing about the dark sky exploits by friends in the lower 48 while you are immersed in the astro-hell of never-ending daylight? Trust me, we’ve been there; we spent 4 years living in North Pole, Alaska just outside Fairbanks, [Read more...]
August is traditionally a real roaster for the northern hemisphere. This month usually sees the onset of what’s known as the Dog Days of summer… but did you know that this term has an actual astronomical tie-in? We’re talking about the dawn appearance of the Dog Star, Sirius. The ancient Egyptians knew this star as the dog-headed god Anubis, and the first sightings of Sirius preceded that most important of calendar dates in their world; the flooding of the life-giving Nile.
The Hubble Space Telescope has shattered yet another record; the smallest Kuiper Belt Object yet recorded. But the discovery came not from the telescope’s main optical array, but an unlikely source; its Fine Guidance Sensors. These star trackers point the HST and sample target stars 40 times a second. Using an innovative technique, a team led by Hike Schlichting sifted through 4.5 years of data to find a single 0.3 second in duration event. This is estimated to be a tiny KBO inclined about 14° degrees to the solar ecliptic. At an estimated 975 meters across and 6.8 billion kilometers distant, this object stands as the tiniest distant object ever detected. The Kuiper belt is a ring of icy material extending just beyond the orbit of Neptune out to about 55 astronomical units. At an estimated +35 magnitude in brightness, this icy body is far too small for even Hubble to see. The object was inferred indirectly by what’s known as a stellar occultation. This discovery also highlights the utility of pouring over the backlog of astronomical data generated by such platforms as Hubble. What other discoveries lay hidden it that thar’ data?
I’ve got a unique challenge for you, as you brush up on your lunar geography in anticipation for next weeks’ LCROSS impact. Next time you’re viewing the waxing gibbous Moon with your friends, amaze them (or make them think your totally crazy) by issuing the off-handed remark; “Did you know that there is a ‘cave’ in the crater Copernicus? The “cave” in question is, of course, an optical illusion. Its interesting to note, however, that in the pre-Apollo era, would-be Selenographers were faced with a lunar landscape that was much less straight forward. This first came to our attention while reading a February 2003 article in Sky & Telescope written by Steven O’Meara. The cave itself rests on the northern inner lip of the crater and is elusive unless caught at the precise sun-angle of 10.7 degrees above the local lunar horizon. This generally occurs around 10-12 days of age, and I encourage you to take a look early this week. [Read more...]
This week’s challenge is an elusive one. With the ecliptic at a high morning angle and the autumnal equinox behind us, now is a good time to attempt to spot the zodiacal light . Look to the east, about an hour or so before local sunrise. [Read more...]
Brace yourselves; the Northern Hemisphere is headed towards Fall!
I know, an equinox may not be the sexiest thing to observe, but its onset has deep significance for those positioned in the northern hemisphere. [Read more...]
The Summer Solstice is upon us: time to set those sun dials… This week marks the beginning of summer in the northern hemisphere, a yearly event in which the sun pauses at its farthest passage north as seen from the Earth and begins its long trek south. This is not a spectacular observational event, and the summer solstice itself only marks a specific moment: June 20th, 2008 at 07:59PM, EDT. What makes this event special is that in 2008, it occurs extremely early, in fact, the earliest since 1896. [Read more...]
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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.
Astro-Event(s): Scoping out the Outer Solar System Action.
All Hail the Harvest Moon!
(Photo by Author).
It’s great to have bright planets lined up in the dusk sky. With the start of school star party season, it gives us diligent ‘scope operators something bright to aim at, even from the most light-polluted of school basketball courts. [Read more...]