Monday, December 8, 2008

A Gibbous Venus...

If you take a look at my post of 12/1, both planets look pretty round. But realizing that Venus goes through a cycle of phases, I wondered if the camera picked up that level of detail. I went back to the original hi res image, and enlarged Venus to get the image posted here. Sure enough, the gibbous phase of Venus is clearly visible in the photo! I'd seen pictures before, but had never observed the phases myself.
Notice that in the 12/1 photo Jupiter, many times larger than Venus and more than 40 times the diameter of the Moon, appears as a small, round dot of light almost 6 times farther from Earth than the Sun - and the nearby Moon was just "passing through" on it's monthly revolution around Earth.

Saturday, December 6, 2008

Amazing Lenticular Clouds over Mt, Rainier

Folks around Mt. Rainier in Washington state were treated to a spectacular display of "lenticular clouds", formed as a wave of moist air moved over the peak on 12/5/2008. Komonews ran a short article which included some fantastic pictures.

You can find a brief explanation of lenticular clouds here on Wikipedia.

Some years ago, I photographed a lenticular over the Adirondack Mts. that was later featured as an Earth Science Picture of the Day.

Sometimes a similar process produces clouds as stable air moves over a rising column of air. I stopped along the Taconic Parkway one summer evening to photograph this example.

Monday, December 1, 2008

Moon, Venus, and Jupiter Conjunction

Last night was a washout...gray, wet, and dreary. Today, the skies cleared and I got this shot at Lasdon Park in Somers this evening. See more pics on my Flickr page. Conjunctions like this are not unusual or rare, but they are quite noticeable and dramatic in the evening sky. (A lunar eclipse like this one in February earlier this year provided another not so unusual but interesting show)

Friday, November 28, 2008

Nice View of the Moon, Venus, and Jupiter This Weekend

Sunday night (November 30), right after sunset, take a few minutes to view the new crescent Moon approaching Venus and Jupiter in the southwestern sky.
Use your fist held at arm's length to measure the angular distance from the Moon up to Venus (the brighter and lower of the 2 planets)- your fist at arm's length is 10 degrees wide. Here's a Stellarium view of what you'll see - the red line is the plane of the ecliptic.

On the evening of 12/1 (Monday night), the Moon will have moved eastward to a position just to the east of Venus. Using your fist again, estimate how far past Venus the Moon is, and add that measurement to last night's to estimate how far eastward among the stars the Moon has moved in the last 24 hours.

Divide that number into 360 degrees to calculate the approximate number of days it takes the Moon to go through a cycle of phases (called the synodic period*) I'll post my results here next week.

*Here's a diagram that explains the sidereal (one revolution) and synodic (one cycle of the phases) of the Moon. If you measured the Moon's eastward progress against the stars, you could calculate the sidereal period. But since Venus is moving eastward against the stars, too (with the Sun), you're really measuring the synodic period.

Now take a look at this LA Times article, and pay close attention to the image. Can you tell what's wrong? Can you explain how it might have happened?

Monday, October 27, 2008

Stealing Sand from Beaches?

Back in the early 80's when I was building my house, a mason told me to get "Cowbay Sand" to make the mortar for the walls of my foundation - that it was worth the extra expense. He told me that Cowbay Sand came from Long Island, and its characteristic mix of particle sizes and shapes help make a strong mortar. The sand was described this way in a recent Port Washington News report:
The sandbanks of Port Washington are more than 20,000 years old, originating when the final glacier left behind mounds of glacial sand and gravel. Since the 1880s, it has been estimated that over 140 million yards of sand were delivered from Port Washington to New York City; enough sand to cover the Empire State Building with sand extending from the East River to the Hudson River and from 14th Street to 59th Street. The sand, known as Cow Bay sand, was of particularly fine quality and used to construct the sidewalks, skyscrapers, water tunnels and infrastructure of New York City.
There's a neat article from Newsday on the Long Island sand industry here, too.
I wondered then, and still do, is there enough sand around to support all the construction that is constantly going on around us?
It turns out that mining of sand is a big business, and apparently often done illegally, on some Caribbean islands where the demand for sand for construction is so great, and the profits so high, that huge sections of beach are literally being stolen over night.

Tuesday, October 21, 2008

Indian Moon Mission to Launch Late Tuesday Evening

Hi all - I know it's been some time since I've posted here - it was a busy summer and fall for me! This story was simply too good not to post, though.
Late Tuesday evening (New York time), the Indian government will launch a spacecraft headed for the Moon. You can read the article here. Among other instruments, the Chandrayaan 1 is carrying an instrument called the "Mineral Mapper" developed by NASA at Goddard Space Flight Center in Maryland. This is of particular interest because Noah Petro, a 1997 Fox Lane grad, is one of the NASA scientists who worked on the project. You can read a report on the Mineral Mapper, prepared by Noah and others, here. After graduating from Bates College in Maine, Noah earned his PhD in planetary geology from Brown University where he concentrated on lunar geology.
Noah has stayed in touch with FL, and just recently joined Drew Patrick, me, and 2 other Fox Lane grad geoscientists for dinner at the national Geological Society of America meeting in Houston.

Sunday, May 18, 2008

Mt. St. Helens Video in Google Earth

While reading the news this morning, I stumbled upon a nice set of Mt. St. Helens before and after shots, and a link to a time lapse video of the building of the new lava dome. Some of what I saw in the video sent me to Google Earth for a closer look, and as usual things are not quite as simple as they seem.

I put together this kml file St. Helens Questions.kmz , with the video and links embedded, and some placemarks with questions and my amateurish attempts at interpretation.

If you open the file in GE, expand the folder that appears in Temporary Places, and click the icons for the video and each placemark, in order, you can follow my convoluted train of thought.

I welcome any and all comments and interpretations.

(maybe we need a field trip? - the snow is FINALLY melting there)

Thursday, March 6, 2008

A Really Neat Way to View Global Statistics

I thought you all might have some fun, and learn something too, watching this guy talk about global health, economic, and pollution trends over time.

The best part is that you can get that software and play with it yourself. I spent WAY too much time in there, but it is really fascinating to watch trends evolve.

Monday, February 25, 2008

Seeing Stars?

You can contribute to an international scientific study of the nighttime sky! The 2008 GLOBE at Night Campaign will run from 25 February - 8 March.
Your participation involves taking about 20 minutes to observe the sky one evening, and to report your observations on line. See the link above for details. Last year about 20 kids from Fox Lane participated.
2008 marks a monumental shift in human history when more than half the people on Earth are expected to be living in cities. Because of the background light in urban area, many city dwellers have never seen a sky full of stars.
During the 2007 event there were 8,491 observations reported from 60 GLOBE countries, almost doubling the observations from 2006.

Thursday, February 21, 2008

Well, Ms. Zhou, Carl T., and I saw it.....

Here's a shot of the Moon in Earth's umbra taken from Pound Ridge Reservation. The star at Leo's "heart", Regulus, is near the top center of the image, and Saturn appears at the lower left.
More photos are on my flickr page

Wednesday, February 20, 2008

Eclipse Tonight! Maybe......

The forecast for this evening is for "mostly cloudy" skies, and it's going to be COLD! I have the telescope packed in my truck, and the coleman stove is fueled up to make hot chocolate, but I'm going to wait until around 7:30 PM to decide if I'm going over to the Pound Ridge Reservation.
If you're planning on joining me there, check back at this blog at 7:30 PM for an update.

Monday, February 18, 2008

Participate in a Climate Study project

For most of my adult life, I've kept track of the date that the maple trees around me first provide shade as their leaves open in the spring. I've noticed that it is happening 2 or 3 days earlier now than it did 30 years ago.

The University Corporation for Atmospheric Research (UCAR) is sponsoring a truly interactive project to monitor when the leaves and flowers of certain plants "pop" in the spring, and they're looking for help from, well, everyone! The project is called BudBurst, and the 2008 season kicked off on February 15. Everything you need to know is on their web page, but essentially you'll be watching specific species of plant, and reporting the dates of bud burst, flowering, etc on an interactive web page. I've already registered, and picked several plants in and around my yard to monitor. The Fox Lane Campus is a great place to find many of the species listed at the BudBurst site, too.

The picture accompanying this post is of pollen released from pitch pines on Schunnemunk Mt. near Newburgh, NY. It was windy the day I was up there, and I came home with a yellowy green tint on my clothing and hair from all the pollen blowing around up there. Pollen release is one of the events the BudBurst team is looking for.

Thursday, February 14, 2008

Join the Westchester Amateur Astronomers at Pound Ridge Reservation...

..on the evening of February 20 to view the Lunar Eclipse (see previous two posts to this blog, and Fred Espenak's eclipse page). The Westchester Amateurs are regulars at the Res, and have gotten the cooperation of the County in making the Res available to all that night. They'll gather at the Meadow at the Ward Pound Ridge Reservation at around 8:30 PM. Weather permitting, I and some of the FLHS staff will be there too, with a telescope! This is not a school sponsored event, but if you (and perhaps your family) decide to participate, kill the headlights as you enter the parking area, and limit flashlight size and use - people's eyes will be adjusted to the dark, and bright lights upset that adjustment. Dress warmly (hat and gloves!). I'll bring a sleeping bag and pad for myself so I can be comfortable as I watch the sky that night.
Bring binoculars if you have them, and a camera and tripod if you want to photograph the event (and telescopes, too - but not unless you know how to use them - it won't be a good time to learn).
Hope to see you there!

Tuesday, February 5, 2008

Lunar Eclipse on February 20

On Wednesday, February 20 you'll have a chance to observe a total lunar eclipse. On the 7th of this month, the Moon will cross the plane of Earth's orbit (called the ecliptic) precisely when it is aligned with the Earth and Sun (at the New Moon phase) and a solar eclipse will be observed from parts of the southern hemisphere. On the night of February 20-21 - just 2 weeks after the solar eclipse - the Moon will once again cross the ecliptic, only this time in Earth's shadow at the Full Moon phase. Just before 9 PM EST, the Moon will enter the darkest part of shadow of Earth, called the umbra, and by 10 PM the Moon will be entirely within the umbra. The moon will appear an orangy-red color, a result of the red light of sunset being refracted into Earth's umbra as it passes through our atmosphere. The photo to the right, taken during the lunar eclipse of March 7, 2007, illustrates that nicely.

The shadow will move from left to right across the Moon as the Moon moves eastward in it's orbit around the Earth.

Make plans to get out to see the eclipse that night. Lunar eclipses are not all that rare, but they are definitely worth observing.

Click here for a detailed diagram and observing times (also available in printable .pdf format)

Sunday, February 3, 2008

February 2008 is Eclipse Month.....

On February 7, an annular solar eclipse will be visible from parts of Antarctica (it will be a partial solar eclipse in New Zealand and part of Australia). Annular means "ring-shaped" and annular eclipses occur when the Moon is far enough away and the Sun is close enough to cause the Moon's apparent diameter to be too small to completely cover the Sun's disk. As a result, at totality, a thin ring of Sun is visible behind the disk of the Moon. It will not be visible from anywhere in North America...Sigh....

But Solar and Lunar eclipses usually come in pairs, and we will be well placed to view a total lunar eclipse on Wednesday night, February 20. Things will get good around 9 PM (Eastern Standard Time) that night, so make your plans now to get out and see it!.
I'll post more on the lunar eclipse later this month.

Friday, February 1, 2008

Freezing Rain and Icicles

Area schools closed today in anticipation of accumulating ice as significant freezing rain fell during the day.

The rain started falling around 10 AM, with my digital thermometer reading 32.5 degrees F. It's been raining liquid water and an occasional ice pellet ever since then (it's now after 2 PM) and whatever is falling is freezing on contact. The picture here is of icicles that formed as liquid water ran off the car and froze.

What's interesting is that the temperature on my digital thermometer has remained constant - right at the freezing point - all day, even though other local stations are reporting slightly colder temps. I think the reason for the constant temp on my thermometer is due to the fact that the sensor in my yard is getting wet, and the water on it is freezing and holding the temperature right at the freezing point.

I've posted a few more icicle pics here.

Venus and Jupiter in the Morning Sky

If any of you have a good view to the southeast just before sunrise, you've probably noticed Venus and Jupiter coming closer and closer to each other over the last couple of days.
This morning, they are in conjunction, passing within just .6 degrees from each other (that's just a hair more than the Moon's diameter). They are located just above the handle of the "teapot" in Sagitarius (the constellation that dominates the southern sky during summer evenings). It's cloudy here this morning, so I won't be able to get a picture, but I did steal this image from Stellarium (
You can get a full size image here:

During the coming weekend, the old crescent moon will move across this part of the sky from the upper left to the lower right. Hopefully I'll get some pics.

Wednesday, January 23, 2008

Some Interesting Weather Observations

The cold, cP air that covered the region last weekend presented some pretty interesting opportunities to explore some of the atmospheric phenomena we study in earth science classes. When a colleague in New Hampshire sent the image of Mt. Washington ("Home of the World's Worst Weather), I began looking at data from the area where the photo was taken, and from the summit of Mt. Washington. What I soon realized was that in this fairly uniform and stable air mass, I could predict the temperature at the summit based on observations at the location where the photo was taken. That night, temperatures on the summit dropped to -31°C - cold to be sure, but not as cold as it might have been.
The two exercises below will help you understand what was going on.
Mt Washington, NH Weather Part 1 and Part 2 (solution to Part 1)
See the solution to Part 1 only if you are stuck (or want to check your answers). You can email if you want an explanation of Part 2.

Tomorrow, I'll post another quick exercise involving the heating and cooling of descending and rising air.

Monday, January 14, 2008

False Alarm on the Big Snow?

Kind of a false alarm on the snow, eh? Look at this weather map from Sunday night into Monday morning (Click the map if you can't see the animation). Subtract 5 hours from the time displayed at the lower left for NY time, and notice that the storm center stayed well out to sea, "wasting" a lot of good snow on the ocean!
A small change in the track of the storm can make a huge difference in the weather a particular area experiences.
Oh well, you got your 2 hour delay in SE NY this morning, right?

Sunday, January 13, 2008

Nor'easter for us this week!

It's been a while since I've posted anything here - so here's wishing you all a belated Happy and Healthy New Year. I've enjoyed seeing some of you during my brief visits to Fox Lane, and hope to see more of you when I'm there again.

A strong low pressure system is developing off the coast of the SE US as I write this, and by this evening it will have moved northward toward the NY area. It is predicted to remain off-shore, so we will be in the easterly and then northeasterly* flow of moist air circling counterclockwise and in off the Altlantic around the low.

Check out the current and forecast weather maps at Accuweather.

That relatively warmer and moist maritime air will override the cooler air already in place over us (remember, warmer and moist air is less dense than cooler, dry air), and as it rises, expands, and cools the moisture in it will condense and fall as snow through the cooler air below. As of noon today (Sunday), the national weather service is predicting 8 to 12 inches of snow in our area.

As the low moves northeastward out to sea tomorrow afternoon, we'll experience a shift in the wind to the northwest, ushering in a little cP from Canada, and another low that's currently spinning around the Great Lakes.
Read more about the developing storm at the Accuweather web site, and check for school closings or delays at your school web page or, in SE New York here
*That's why it's called a nor'easter!