Eagles Fan in 'Skins Land

On Monday night (1/7/08), around 9 PM, my girlfriend and I saw a large fireball in the south-southeastern sky, just above the treeline on the National Mall near the National Gallery of Art Sculpture Garden.  It was hazy with high clouds, but the meteor still was the brightest object in the sky for about 3 seconds, moving slowly from east to west on a diagonal toward the ground and shining at magnitude -6 to -7 by my estimate.

Anyone else happen to see that?  It was probably the brightest fireball I've ever seen, and I saw one in broad daylight last year, too.

OK, it ain't much, but I'm definitely looking forward to that 60% chance that 1 to 2 inches of the white stuff will fall tomorrow.  Interestingly, this snow is forecast almost to the day the first flakes fell on the area last Dec. 7 (a trace at National Airport, according to the National Weather Service).  And I'm also hoping that we get something big this winter!

Sue Palka, make it happen!

2002 Leonids, from Manassas Battlefield (the bright "star" near the meteor in the upper right is actually Jupiter)

The annual Leonid meteor shower peaks tomorrow morning (Sunday, Nov. 19) before dawn.  In a normal year like this one, the shower, formed from the orbiting debris leftover from Comet Tempel-Tuttle, yields at best only a dozen or so meteors per hour.  However, from 1998-2002, we were treated to a series of spectacular storm events (officially, 1,000+ meteors per hour) after the comet's last passage around the sun in 1998.  The greatest storm happened early on November 18, 2001, with thousands of meteors per hour reported around the world in two separate, but distinct peaks.  I drove all the way out to Manassas Battlefield very early that morning to watch it, and was joined by hundreds of others who parked up and down US-15, where the sky was dark and the police really didn't mind.  I remember at one point just before both dawn and fog took over seeing meteors seem to rain from the sky, about 3 to 6 per second with many fireballs for several minutes.  That's something I'll never forget.  The next year, I went back to Manassas, and while it was also a good show, it was not even close to a repeat performance of 2001.

Alas, we won't see another Leonid storm again in our lifetimes, as Jupiter will steer the comet and debris field clear of us.  But if somehow you're still around in the 2090s, watch the skies in mid-November!

The weather finally cleared enough this morning for me to try to find Comet Holmes, which, as noted by Greg "SkyGuy" Redfern, has a coma (dust cloud) larger than the sun.  That size, however, does not make the comet easier to see -- the overall brightness has not diminished (it's still around magnitude 2.5 to 3.0), but it is now distributed over a wider area.  The comet is now passing very close to Mirfak (alpha Persei), the brightest star in Perseus, and it was hard to find with the naked eye here inside the Beltway.  Note that there might have been leftover haze and other atmospheric clutter, but also note that I could not get a good picture of the comet without keeping the shutter open for almost half a minute (I'll post later on).  Binoculars show a diffuse, greenish cloud near Mirfak.  Based on this observation, it's possible that peak unaided viewing for Holmes has passed, barring another unexpected outburst, as moon interference will wash out the sky in the next two weeks.  We'll have to wait and see what happens!  Also note that on November 19, the comet will appear to encompass Mirfak, which should be interesting.

Comet Holmes continues to shine at around magnitude 2.5, or about as bright as the stars in the Big Dipper.  The comet's coma (head) has expanded to about half the size of a full moon, and looks anywhere from greenish to yellowish.  Long exposure photographs have shown that a short and stubby tail has formed, but to the naked eye or binoculars, it doesn't really have the "classic" cometary appearance that we saw with other famous comets like Hale-Bopp or Halley.  There are several factors, the main ones being its distance from the sun (closing in on Jupiter's orbit), and its position relative to both the sun and earth.  Comet tails always point away from the sun, and we're seeing it almost head-on, and it will remain this way for the next few months.

No one's sure how long Holmes will stay bright enough to see unaided inside the Beltway, but we do know that the moon will start to intrude around November 15, on its way to the next full phase on November 24.  With uncertainty in the forecast, it's best to catch the comet now, before the moon washes out the sky.  Keep looking high north/northeast to the lower right of Cassiopeia's "W" in the evening, and in the northwest sky in the early morning hours.

Here's a 15-second exposure from 11/6, which I took in Arlington.  If it were visible, the tail would be pointing to the upper right.

Don't know if it was the costumes or the campy "acting" (not that I'd do any better),  but you guys had me laughing out loud!  Can't believe no one's mentioned it yet.

From skyandtelescope.com:

Future prospects (by Alan MacRobert). "My bet is this comet will stay bright for a long while. The yellow-white color is dust reflecting sunlight, and dust is what keeps a comet bright. As opposed to gas (comet gas is green and blue), which blows away quickly in the solar wind. Also, the brilliant stellar nucleus and the inner-coma fan suggest that the nucleus us still producing a lot of dust. This comet won't fade out soon.

"As for a tail: I expect it'll be short and stubby when or if it forms. The tail should be pointing more or less away from Earth in space — we're looking down its length — since the comet is only about 45° away from the point in the sky opposite the Sun. The size of this angle won't change a lot in the next couple months."
---

Skies are due to clear out by tomorrow night, though a bright near-full moon hovering nearby could be a problem.  Still -- can't wait to check this out!

Here's something you don't see every day.  Last night, Comet 17/P (Holmes) suddenly brightened by a factor of 400,000, from magnitude +17 to around magnitude 2.5, visible to the naked eye in big cities.  Astronomers don't understand why this happened, and who knows how long this outburst will last, as the comet is already speeding away from the sun and is far away from earth.

When the skies finally clear out later this week, look for Comet Holmes in the constellation Perseus, high in the north and northeast all night.  Admittedly, it doesn't look like much more than a fuzzy yellowish star, but binoculars or a telescope will bring out more details (but no tail).  Even so, it's an unusual object, and naked-eye comets are relatively rare.

Story: http://www.skyandtelescope.com/observing/highlights/10
775326.html

Finder chart (hey, how do you post pictures?): http://www.spaceweather.com/images2007/24oct07/skymap_
north_holmes.gif?PHPSESSID=aejgtg7le800dh6i2tficj2pn4a>

This morning, I was surprised to log on to CNN.com and see the link "Atlantic's 1st named storm forms."  Looks like Mother Nature's throwing the book at us and ignoring our ordered calendar by tossing Subtropical Storm Andrea out at the Southeast coast.  Andrea evolved from a persistent mid-latitude gale center that has been drifting off to the southwest over the past few days, and has been at least partially responsible for our recent cool snap and gusty winds. 

"Subtropical," you say?  In 2002, the Tropical Prediction Center decided to start naming storms that exhibit both tropical and mid-latitude characteristics; that is, systems that contain the elements of warm central cores of tropical storms as well as the cold and warm fronts that define non-tropical systems.  These not-quite-tropical storms are typically less powerful than true warm-core systems because the energy is spread out over a wide area rather than concentrated toward the center.  Thus, it would actually be nice if Andrea decided to plow ashore into the parched Southeast rather than meander off the coast for the next few days before dissipating, which is the official forecast.

But back to hurricane season.  Forecasters, fresh from being burned by last year's El Nino-influenced dire-predictions-gone-wrong prognostication (but probably happy about it), are once again predicting more tropical storms than normal for the Atlantic and the Gulf.  While this could be bad news for anyone with property on the coast, inland areas that are now rain-starved may benefit from soggy remnants of big storms.  And keep in mind that a higher storm count doesn't necessarily mean that the coast will get pummeled more than normal (in 2003, Isabel was the only storm out of 21 that caused any kind of real damage to the U.S.).

And despite the notoriety they get, hurricanes are one of nature's ways of keeping the planet's climate balanced by transferring warm air north.  We just happen to get in the way, for better or for worse.

Spring has sprung!  The grass has...aw forget it.  I'm not a poet, so you won't get a real ode from me.  Spring means a lot of things to me, not the least of which the almost constant aggravation from tree pollen from now until about Memorial Day.  That's one of the many reasons why I enjoy winter so much.  But even as I dread the annual assault on my sinuses, I can't help but notice the rebirth of everything green around me.  Today, I saw my first butterfly of the year, an eastern comma (yes, that's what it's called) on Roosevelt Island.  The rest of the island is starting to turn different colors besides the gray that it has been since November.  Winter's woodpeckers and sparrows have been joined by other, more colorful species which will soon be lost in the sea of green canopy that will replace sterile, bare branches.  And in the tidal pools under the year-round resident ducks and geese, little fish swim frantically and feed on the new algae bloom, to be joined later by the ospreys and terns that will hunt them.  Just south of the island, the Tidal Basin is preparing for its annual rite of spring, as the cherry trees seem to be in a state of pause, with an explosion of white and pink imminent.  And everywhere, people seem to be in a better mood.

Don't get me wrong -- I dread the inevitable and sometimes humbling hay fever attack that can happen at any time, Claritin or not.  But I still can pause and enjoy the beauty of nature's annual rebirth.  Besides, baseball is less than a week away. 

Happy Spring.

The following are predicted times (EST) for Saturday's lunar eclipse, courtesy of NASA and the U.S. Naval Observatory's website:

 

Moon enters umbra (earth's main shadow) = 4:30 PM (moon still below horizon)

Total eclipse phase begins = 5:44 PM (moon still below horizon)

 

Moonrise = 5:58 PM

Sunset = 6:03 PM

 

Emergence from umbra (end of totality phase) = 6:57 PM

End of eclipse = 8:11 PM

The small cities of Manassas and Manassas Park, Virginia, are literally right next to each other.  So how did Manassas officials decide to close schools on Thursday, while neighboring Manassas Park is opening one hour late?  I don't get it!

In my travels, I have heard many, many people, friends and strangers alike, say bad things about weather forecasters. "They were wrong." "They lied." "They can't get anything right." Being a closet wannabe meteorologist, I am always trying to defend the industry, giving reason after reason why:

1) Weather has always been tough to forecast, and
2) You really can't tell from the looking out the window in the morning how the rest of the day will turn out.

I hear most of these complaints in winter, as weather takes center stage in work and recreational plans. Bad winter weather tends to be far more disruptive than anything the other seasons can churn out, discounting out of the ordinary events like hurricanes and tornado outbreaks. And everyone likes to talk about snowfall predictions and how they do or don't pan out after the fact.

But why exactly is winter weather so hard to forecast? Simply put, it's location, location, location. We live in a unique part of the world, where cold air coming out of the interior often clashes with milder, moist air from the Atlantic and the Gulf of Mexico, creating large coastal storms with different kinds of precipitation. Whenever one of these "nor'easters" form, you'll hear Sue or Tony or Gary or Gwen or Tucker mention the "rain/snow line," that ubiquitous imaginary boundary between snow and that dreaded wintry mix to rain, the line in the clouds between a day off from school or work and a miserable cold rain or slushy mix that no one wants to be in. This is because a coastal storm draws that warmer Atlantic air into itself, mixing in with the colder continental air and dropping precipitation in varying forms. Generally speaking, if you are to the left of the storm center, you'll get all snow. Closer to the center, you may get a wintry mix, while the right of the center gets mostly or all rain. Of course, this setup can vary greatly based on the amount of cold air available. The big I-95 cities of New York, Philadelphia, Baltimore and Washington often fall along the rain/snow border, and meteorologists almost always have a tough time trying to predict exactly where that line will actually end up. A number of other factors come into play, including, but not limited to, battling polar and subtropical jet stream branches, the curious phenomenon of energy transfer from a storm in the interior to the developing low pressure area off the coast, which may suppress snow totals in the area between the storms, and the presence of a dry air slot in the storm's lower left quadrant caused by the storm circulation's interaction with land.

No one completely understands the overall mechanics of these storms, so we are left with using probabilities in forecasts. Keep in mind that you'll probably never see a 100% probability of snow until the storm is in progress. Last week's mostly rain event never got past an 80% chance of snow until it became apparent that the storm wouldn't materialize. And an 80% chance of snow means a statistically significant figure of 20% that it won't.

So the moral of my story is: cut the weather guys a break when things go wrong in winter. They're not out to get you or get higher ratings for their networks. They're doing their best -- and overall they predict weather a lot better than we can!

Kudos to the graphics people who designed the 3-D "Anatomy of a Tornado" diagrams for tonight's newscasts. Very informative while being simple to understand for the public at-large.

Too bad we've been socked into a cloudy pattern -- observers all over the world have been reporting that Comet McNaught is easily found with the naked eye in broad daylight! It is the brightest comet since Ikeya-Seki in 1965 and the second brightest in the past century. The comet now around magnitude -6 (brighter than Venus) and has now rounded the sun and is headed rapidly toward the night skies above the Southern Hemisphere, so we'll never see it in dark skies again, but for the next few days it will be below the sun during the day. How long it will remain bright enough to spot in daylight is uncertain -- since it has now passed its closest solar approach, the comet will start to lose steam and get noticeably fainter within a few days. Our next clear day appears to be Wednesday, which may be too late. But keep those fingers crossed!

Daylight photos of Comet McNaught can be found at Spaceweather.com.