Astronomy Archives

February 20, 2008

Total Eclipse Tonight


Living in a major urban area, you usually miss out on a lot of the cool/nerdy astronomical phenomena, like meteor showers, due to the amount of light pollution. But not so tonight (Feb. 20): even city dwellers should be able to view a total lunar eclipse, from about 8:43 p.m. (E.S.T) till a few minutes past midnight. If you don't want to crane your neck upward for that long, the "total" part of the eclipse goes from 10:01 until 10:51, according to NASA.

Of course, an eclipse is not visible if clouds block your view of the moon. If that's the case in your area, check out the Clear Sky Clock, which lists astronomers' forecasts and could offer a nearby location where the clouds have lifted enough for viewing.

Then next total lunar eclipse won't take place until December 21, 2010.

Total Lunar Eclipse: Feb. 20, 2008 [NASA]
'The Eclipse That Saved Columbus' [AFP]
Clear Sky Clock

Composite of a total lunar eclipse by Fort Photo.

December 6, 2007

Autumn on Uranus

0712Uranus.jpgUranus is at its equinox December 7, meaning the Sun will be shining directly on its equator. Uranus tilts dramatically (98 degrees) on its rotational axis, while the Earth's tilt is a mere 23 degrees—so while Autumn for the Earth's northern hemisphere runs from Sept. 22 through Dec. 21, "Autumn" in Uranus' southern hemisphere begins December 7 and lasts until, well, 2028. At that point, its south pole will be facing almost completely away from the Sun. Uranus' last equinox was in 1965 and the next one will not be until 2049.

The long read on what can be gained from observing the equinox: Uranus nears Equinox (PDF) from a meeting of the Outer Planets Assessment Group (OPAG)

Uranus, found by Sir William Herschel in 1781, was the first planet discovered using a telescope. Herschel originally named it Georgium Sidus (George's Star) after his patron, King George III. It wasn't until later that Johann Bode recommended that it be named after the father of the Titans in Roman mythology, much to the joy of bored students everywhere.

Uranus profile and news (The Planetary Society Weblog)
Happy Uranian Equinox, a once-in-a-half-lifetime event (Science Blog)
Seasons on Uranus (American Museum of Natural History's Hayden Planetarium)

Keck II composite image of Uranus taken on May 28, 2007 using two different types of infrared light. Credit: W. M. Keck Observatory (Marcos van Dam)

November 29, 2007

November's Greatest Hits

World Almanac 2008 StacksNew to the World Almanac blog? Today's your lucky day: here's a roundup of some featured entries from recent weeks.

The World at a Glance: 2008 Edition
What's the most popular tourist destination in the world? The fastest roller coaster? How much fat does the average American consume each year? A roundup of some of the year's most interesting facts, straight from the pages of The World Almanac 2008.

Less Reading in the United States
The National Endowment for the Arts says that teenagers and adults are reading less, and less well. What's on your reading list?

Word of the Year
What the heck is "bacn"? Read up on The Oxford Word of the Year (and its runners-up) to find out.

Talking Turkey
The truth behind the history of the Thanksgiving "turkey pardon" at the White House

A Festival of Lights, In Space and On Earth
For most people, Comet Holmes has grown too dim to see with the naked eye, but you can still spot it with the help of binoculars or a telescope. Catch up on all the Holmes-ian news with this previous post.

November 16, 2007

Release Week Randomness

55 CancriSometimes these Thursday-morning Wake Up With Whoopi appearances go exactly as planned, and sometimes... well, sometimes this happens: everyone gets hopped up on the chocolates I bring in for Whoopi's birthday (which happened to be the same day The World Almanac 2008 was released), and then her co-host Cubby tells an admittedly cool story about spotting his own name in the book... and then suddenly I have no time to share all the great facts I prepared about extrasolar planets.

So, they'll have to wait for another week.* At least we did managed to kick around some facts from one of this year's The World at a Glance pages, which collect all sorts of facts you might not have known were in the book, including top-grossing concert tours, top tourist destinations, per capita fat consumption in the U.S., most popular car colors...


Tune in next Thursday morning for some Thanksgiving history, which I promise will go according to plan.

Previously: The World at a Glance

Image: Artists' conception of 55 Cancri and newly discovered planet (which I didn't get to talk about!)

(* ...or you could get an overview of the search for extrasolar planets on page 333 of the new World Almanac.)

November 8, 2007

A Festival of Lights, In Space and On Earth

Comet Holmes.jpgLiving in New York, sometimes you forget to look up and enjoy the night sky—but if ever there was a time to do so, it's now. Dedicated skywatchers should know by now about Comet Holmes (at right), which just a few weeks ago erupted, becoming nearly a million times brighter practically overnight. Before Oct. 23, the comet was visible only through a telescope, but a sudden and rapid emission of dust particles made the comet visible to the naked eye by the following day. From the Associated Press:

The comet is exploding and its coma, a cloud of gas and dust illuminated by the sun, has grown to be bigger than the planet Jupiter. The comet lacks the tail usually associated with such celestial bodies but can be seen in the northern sky, in the constellation Perseus, as a fuzzy spot of light about as bright as the stars in the Big Dipper.

This isn't the first time Holmes has undergone a sudden and dramatic change; here's a clip from The Baltimore Sun, Feb. 9, 1893: Erratic Comet Holmes

Astronomers aren't certain how much longer the comet will be visible in its current, extra-bright form; it could be months or just a few more weeks, so outer space buffs should check out this once-in-a-lifetime event as soon as possible. Why not do it tonight? He didn't have anything to do with discovering comet Holmes, but it is, fittingly, Edmond Halley's birthday. You can find a simple guide to locating Comet Holmes at And you can listen to today's brief comet-chat on Wake Up With Whoopi here:

Diwali handsIf you're looking for a more earth-bound celebration of lights, you're in luck this week: I was just reminded by Ajay, our excellent webmaster, that he will be celebrating Diwali (or Deepvali) this Friday. The festival, whose name comes from the Sanskrit dipavali ("row of lights") is one of the largest celebrations in Hinduism—a five-day festival which, at its most basic level, celebrates the victory of good over evil. Throughout the festival, celebrants set oil-filled lamps outside buildings and set them adrift on rivers; the main festival day, tomorrow, marks the Hindu new year, and is celebrated with gifts, fireworks, feasts... and even gambling, commemorating legendary games of dice said to have been played by Hindu gods.

And yes, like so many other holidays, Diwali has undergone some commercialization in recent years. Some trends cross all cultural boundaries.

See Comet Holmes Tonight! (
Comet Holmes roundup on Google News
Hindu holiday of Diwali attracts attention of businesses (Houston Chronicle)
Diwali Specials (recipes from Saroj's Cookbook)

Comet Holmes Grows a Tail (NASA Astronomy Photo of the Day; copyright Vicent Peris and José Luis Lamadrid (

Hands in Hands (Kunal Daswani)

October 25, 2007

The Bright Side of the Moon

Moon: Apogee and PerigeeNASA's Astronomy Picture of the Day is a constant source of pleasure and enlightenment—many images are chosen just for their beauty, but sometimes timely and informative gems pop up, like today's entry about the Moon's perigee.
Tonight, those blessed with clear skies can enjoy a glorious Full Moon, (exact full phase at 0452 UT, October 26). In fact, the Moon will reach its full phase within a few hours of perigee, the closest point in its elliptical orbit, making it the largest Full Moon of 2007. ... The difference in apparent size between the largest and smallest Full Moon is quite dramatic and similar to this side by side comparison of the lunar apogee/perigee apparitions from 2006.
For serious skywatchers and casual Hubble-hounds alike, the APOD is a treasure trove of gorgeous space imagery. Hit the links below to explore the site, or subscribe to the RSS feed. NASA's official feed of thumbnail images is provided, for those who prefer a "lite" version; also available is an unofficial feed that delivers full-size images to your feed reader.

Astronomy Picture of the Day (NASA)
APOD RSS Feed (official NASA feed, thumbnail images)
APOD RSS Feed (unofficial feed, full-size images)

August 2, 2007

The Virtual Universe

2007-08-02_170023.jpgRight now I'm reviewing the Astronomy chapter for the upcoming 2008 World Almanac—so it was a nice coincidence to run across this link. runs down a list of "The Top Five Virtual Sky Simulators," each of them catering to slightly different levels of interest and expertise.

Need some help making sense of the nighttime sky? Click through and get some fast (and free) electronic assistance.

Top Five Virtual Sky Simulators (

April 5, 2007

Size Matters

planetsize.jpg Via the always-enlightening Information Aesthetics, here are two different looks at the relative size of objects in the Solar System and beyond.

First is a straightforward lineup of objects in our astronomical neighborhood, from the Sun down to the 203-mile asteroid Davida (click at right to view the full image). I've seen graphics like this before, but can't recall seeing one that included so many moons and other small bodies. The zone from Callisto through Ceres was oddly surprising to me.

Second, a cool little video that sends you spinning in the opposite direction, from the smallest planets to the most massive stars. The first half left me thinking, again, "Seen it before," but once you pass the Sun, the leaps in size become truly mind-boggling.

January 8, 2007

Do You Ever Look Up in the Sky, and Wonder…

space_ritual.jpgSure, there are all sorts of facts about space in the new edition of The World Almanac, but we don’t say what would happen if a satellite fell to earth. We don’t contradict claims that the moon landing was really a hoax. And we also don’t explain your chances of being sucked up by a black hole. Go to Get a Straight Answer for facts on these and many other important space issues brought to you by retired NASA astrophysicist David P. Stern. One I found particularly amusing is after the jump.

Continue reading "Do You Ever Look Up in the Sky, and Wonder…" »

December 5, 2006

Discovery's 33rd Launch

Photo from Last night at 11 p.m. (EST), NASA began the countdown towards the launch of the Discovery space shuttle, its 33rd mission (find information on earlier missions in the Almanac's Memorable Moments in Human Space Flight section p.314-317). Due to launch at 9:35 p.m. (EST) Thursday, the STS-116 mission will be delivering and installing new pieces of the International Space Station including the $11 million, 4,000-pound P5 integrated truss segment. They will also be dropping off flight engineer Sunita Williams to replace Thomas Reiter as the third member of ISS’ Expedition 14.
Included in Discovery’s seven person crew is Sweden’s first astronaut, Christer Fuglesang. (Välkommen till världsrymd Christer!)
Extra cool bonus fact: that flood of water unleashed seconds before a shuttle’s launch isn’t meant to keep things cool. The water actually breaks up acoustic waves so they don’t damage the shuttle.

NASA will be blogging the launch starting at 3:30 on Thursday.
Or watch the whole thing in streaming video here.
Crew photo from

About Astronomy

This page contains an archive of all entries posted to The World Almanac in the Astronomy category. They are listed from newest to oldest.

Associations is the previous category.

Awards is the next category.

Many more can be found on the main index page or by looking through the archives.

Creative Commons License
This weblog is licensed under a Creative Commons License.