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Solar Eclipse 08 March 2016 March 8, 2016

Posted by aquillam in Astronomy.
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Tonights solar eclipse might not be visible in the US, but that doesn’t mean you have to miss it!

Watch on NASA TV, and learn more about the research astronomers and planetary scientists can do:

Partial Solar Eclipse Observing October 16, 2014

Posted by aquillam in Astronomy, Galileoscope, MichiganAstro, Urban Observing.
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There’s only a week left to get ready for the partial solar eclipse! Since it is only a partial, there is never a moment when it will be safe to look at the sun without proper protection.

It’s so important, I’ll say it again:

DO NOT LOOK DIRECTLY AT THE UNFILTERED SUN.

Got a small ‘scope and want a way to view the sun safely with it? How about building a sun funnel! Get the directions for a sun funnel from the transit of Venus site.

Don’t have the patience for that much effort? Projection screens are simpler, but you’ll have to keep an eye on your telescope to make sure nobody tries to actually look through it. In fact, I don’t recommend using this method at star parties or public events. Most non-astronomers don’t know how to tell the difference between a filtered and unfiltered telescope. Even if you make the tripod short and project onto the ground, that just makes it perfect for a curious four-year-old. However, for yourself or an older audience, this is a very quick and easy way to observe the sun. The simplest version of this this is a white piece of paper on a clipboard, held in front of the eyepiece. If you’re going to use a projection screen, make sure you have real glass eyepieces. Nothing like having eyepiece go up in smoke halfway through the eclipse. If you are using a Galileoscope, you probably shouldn’t use the eyepiece that came with it.

This screen is mounted on a dowel, which is zip-tied to the telescope. I've still had kids try to squeeze their head in against the dowel.

This screen is mounted on a dowel, which is zip-tied to the telescope. I’ve still had kids try to squeeze their head in against the dowel.

No telescope? You can do the projection with a pair of binoculars to. Again, keep a close eye to make sure no one actually looks through the binoculars.

If you have no optics whatsoever, you can still watch the eclipse. Just poke a hole in a piece of paper and project the image onto the ground or another piece of paper.  This isn’t a great way of looking for small features like sunspots, but it will certainly show off of eclipse. For that matter, so will the shadow of a leafy tree.

A solar eclipse viewed using leaf shadows. Click for original image and more information.

Urban Observing October 2014 October 6, 2014

Posted by aquillam in Astronomy, MichiganAstro, Urban Observing.
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Special Events

October makes up for a couple fairly quiet months with several events.

eclipses

October gets off to a great start with a lunar eclipse on the 8th. You can read my earlier post about it, or check out http://www.timeanddate.com/eclipse/lunar/2014-october-8 to get details about observing it where you are. If it isn’t visible or the weather is bad, check out one of the many live feeds from the Griffith Observatory, Slooh.com, or Stargazers.

The Moon and Uranus in the west

Uranus is just off the limb of the partially eclipsed Moon ot 5:45 AM on October 8.

Whenever there’s a lunar eclipse, there should be a Solar eclipse two weeks latter. Most of the US will get at least a piece of this partial eclipse on October 23. I’ll post more about that in a couple weeks. To check if you’ll be able to see it and how much of the Moon will be obscured, check out http://eclipse.gsfc.nasa.gov/SEsearch/SEsearchmap.php?Ecl=20141023 or http://www.timeanddate.com/eclipse/solar/2014-october-23.

Meteor Showers

The Draconids run roughly Oct 6 – 10, and peak on the morning of the 9th. The nice thing about this shower is this is circumpolar for anyone in the US or Canada. The bad thing is the peak rate is only about two meters per hour, they tend to be faint, and it’s the day after the full moon, so it’s only really worth watching for the diehard meteor fans.

The Orionids on the other hand are much more worth watching. They run October 1 through November 14 but peak on the evening/morning of October 21 – 22nd. In a typical year the peak is 20 to 25 fast-moving meters per hour. Exceptional years can produce 50 to 70 meteors per hour. Check the American Meteor Society homepage, http://www.amsmeteors.org/ a few days before to find out if this is expected to be an exceptional year. Orion rises at 11:15 on the 21st, and transits at about 5 AM on the 22nd. With sunrise just before 8 AM, the best time to watch for these meteors will be about 4 – 6 AM.

The starfield centered on the stars of Orion.

The radiant of the Orionid shower is just above the constellation. The map is for 5 AM on Oct 22.

A Comet at Mars

On October 19, comet Siding Spring has a close encounter with the planet Mars. It will pass a mere 132,000 km away from the planet, which is close enough for their atmospheres to interact. What better time for two new space probes to arrive at Mars! In fact, the Mars exploration teams at NASA are so excited they dedicated a page just to comet Siding Spring: http://mars.nasa.gov/comets/sidingspring/. Expected to be around magnitude 10, you’ll need a telescope to spot the comet.

Stick figures of Sagittarius and Ophiuchus  highlight the position of Mars and comet Siding Spring

Mars and comet Siding Spring low in the southwest at 9 PM on October 20.

Moon phases

Full on Oct 8
New Moon Oct 23

Planets:

Mercury is sinking fast in the west as the month begins. Look for it in the morning skies beginning around Oct 21. Greatest westward elongation is actually on Nov 1, so the last few days of the month should be a great time for morning observers to catch this elusive planet.

Mercury in the twilight sky.

Mercury before dawn on Oct 25. Venus and the Sun are aligned just below the horizon.

Already lost in the Sun’s glare at the start of the month, Venus is headed for superior conjunction on Oct 25. It’ll appear in the evening skies around early December, and those long winter nights should make for spectacular Venus observing.

Mars is getting farther away from us as it approaches the Sun this month. Matched with it’s rival Antares, and not far from Saturn, it makes a beautiful naked eye observing opportunity at the beginning of the month. It slowly drifts away from Saturn as the month progresses. On Oct 27 & 28 a fat crescent Moon passes it.

The Moon and Mars at 8 PM on Oct 27.

The Moon and Mars at 8 PM on Oct 27.

Jupiter is the gem of the morning skies this month. A fat waning crescent Moon passes it on Oct 17 and 18th.

The crescent Moon and Jupiter.

The Moon passes near Jupiter on the mornings of Oct 18 & 19. Chart for 6 AM on Oct 18.

Saturn disappears slowly into the sunset this month. Look for a very young Moon in conjunction with Saturn on Oct 25.

Neptune hangs out in Aquarius this month. It’s actually quite close to the 4th magnitude star Sigma Aquarii.

Uranus, Neptune and Sigma Aquarii are marked in the starfield.

Looking SSE at 10 PM on Oct 17. Neptune is just above Sigma Aquarii in the south. Uranus is in the southeast.

Uranus is at opposition at the start of the month, so it’s a great time to observe this distant world. Catch it on the morning of October 8 when it sits just off the limb of the eclipsed Moon!

April 2014 Annular solar Eclipse April 27, 2014

Posted by aquillam in Astronomy, MichiganAstro, Urban Observing.
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In general, the Moon and the Sun have about the same angular size (ie they both cover the same amount of sky.) However, the Moon is very close, and its orbit is elliptical orbit, so its size changes slightly, glowing a tiny bit larger when it is close, and a tiny bit smaller when farther away. Most of the time, that change in size isn’t really noticeable. No so with eclipses.

The image was lightly colorized to emphasize the location of the shadow, but it gives a perspective of the size of the Moon's shadow on the Earth.

The image was lightly colorized to emphasize the location of the shadow, but it gives a perspective of the size of the Moon’s shadow on the Earth.

An annular eclipse occurs when the Moon is at it’s farthest from Earth, so it looks smaller, and its shadow on the Earth is smaller. It can’t completely block out the entire disk of the Sun. People standing in the shadow see an “annulus” or ring around the Sun. This is the type of eclipse that will happen on April 29, 2014.

"ring of fire" solar eclipse by Kevin Baird.

“ring of fire” solar eclipse by Kevin Baird.

Maps of eclipse visibility are available on the NASA eclipse site, http://eclipse.gsfc.nasa.gov/OH/OH2014.html#SE2014Apr29A. You’ll notice this eclipse also is best viewed from Australia or Antarctica. Instead of a quick trip to a possibly hostile environment (it’s almost winter there now), how about watching on one of these sites: