2004 Comet Cruise Page
For Bright Comets Q4 (NEAT) and T7 (LINEAR)
Comet Hale-Bopp in 1996 showing two tails, the yellowish dust tail and blue ion tail.
Image by Thomas Bisque copyright Software Bisque and used by permission.
2004 Featured AstroCruises (TM) Comet Cruises
- Southern Hemisphere Double Comet Cruise, Cape Town to Ft. Lauderdale
on Crystal Serenity (both comets visible and predicted brightening to 2nd magnitude)
April 6-May 2, 2004, 26 nights large-ship luxury, fares from $11,145*
- Mediterranean Comet Cruise, Rome to French Riviera
on Seabourn Legend (Comet Q4 NEAT predicted at first magnitude during waning moon)
May 9-16, 2004, 7 nights small-yacht luxury from $3995*
An Infrequent Heavenly Treat
One of the rarest and most spectacular — and most unpredictable — of naked-eye astronomical phenomena is a bright comet.
Comets don't streak through the skies like meteors. A meteor usually lasts for a fraction of a second and occurs when a bit of interplanetary space debris collides with Earth's atmosphere. Instead, a comet travels toward and then away from the sun far outside of Earth's atmosphere, seeming to hang in the heavens for weeks or months and with at least one tail stretched out behind it. Most meteors are caused by particles about the size and consistency of cigarette ash; comets are considered "dirty snowballs" of frozen gases, water ice and solid particles, and most have nuclei less than six miles across (the nucleus of Halley's Comet is about 7-8 miles in diameter and Comet Hale-Bopp's nucleus is about 25 miles across, but a comet's tail can be 150 million miles long). Meteors can be caused by the solid particles from the tails of comets — the Eta-Aquarid meteor shower (May 6) and Orionid meteor shower (October 21) are both caused by tiny pieces of Halley's Comet.
According to the International Comet Quarterly of the Harvard-Smithsonian Astrophysical Observatory, since 1935 on average we have been able to view a naked-eye comet brighter than second magnitude about once every 5 or 6 years, a comet brighter than first magnitude every 10 years or so, and a comet brighter than zero magnitude roughly once every 15 years. In 2004 there are two comets predicted to be brighter than second magnitude, which would be the brightest comets since Hale-Bopp. They are expected to brighten to easy naked-eye visibility by early April, and both are predicted to be at their brightest in early or mid-May.
After a comet's discovery, we can accurately predict when and where a comet will appear and have a good idea of when it will be brightest. What is harder to forecast is exactly how bright the comet will be, and how far the tail will stretch across the sky — or even how many tails the comet will have!
Two Bright Comets in 2004
The two recently discovered comets, Comet Q4 (NEAT) and Comet T7 (LINEAR) are both expected to brighten to first magnitude, about as bright as the brightest stars (but whose brightness is not concentrated in a pinpoint of light). Comet Hyakutake (brightest in March 1996) was the last first-magnitude comet seen from Earth. It had a bright head (coma) about two degrees in diameter and a tail reported at 70-100 degrees in length (your fist held at arm's length is about 10 degrees). Comet Hale-Bopp in 1997 was even brighter than first magnitude, with both a blue ion tail and yellowish curved dust tail at least 25 degrees long. An ion tail is caused by gases from the comet blown back and glowing in the solar wind, while a dust tail is caused by sunlight reflecting off the solid particles left in the wake of the comet. If you want to see the details and full length of comet tails, it is important to view these dim phenomena from a dark-sky location.
Comet Q4 (NEAT) should be visible to the naked eye in early April in the southern hemisphere, and by early May should present an excellent appearance in the northern hemisphere. Comet T7 (LINEAR) isn't at as great an angle from the sun, but should be visible in some latitudes from mid-April to mid-June, first before dawn and then after dusk.
How will comets Q4 (NEAT) and T7 (LINEAR) appear when they approach Earth in April, May and June of 2004? While comets don't always live up to expectations (Comet Kohoutek in 1974 and Halley's Comet in 1986 come to mind), part of the excitement for stargazers is the anticipation and unpredictability of it all. As famed comet hunter David H. Levy said, "Comets are like cats; they have tails, and they do precisely what they want."
Predicted Brightness of Comet Q4 (NEAT)
Becomes Brighter than Dimmest
Little Dipper Star | Becomes Brighter than Dimmest
Big Dipper Star | Comet Brightest | Comet
Magnitude | No Longer Brighter than Dimmest
Big Dipper Star | No Longer Brighter than Dimmest
Little Dipper Star |
|---|
| April 2 | April 25 | May 7 | 0.9 | June 2 | June 25 |
Predicted Brightness of Comet T7 (LINEAR)
Becomes Brighter than Dimmest
Little Dipper Star | Becomes Brighter than Dimmest
Big Dipper Star | Comet Brightest | Comet
Magnitude | No Longer Brighter than Dimmest
Big Dipper Star | No Longer Brighter than Dimmest
Little Dipper Star |
|---|
| March 23 | April 10 | May 20 | 0.3 | June 3 | June 13 |
Since the widespread use of artificial light in the past century, truly dark skies have become harder and harder to find. These days one of the best places to view a celestial event is on board a ship at sea, far from the light pollution that seems to be everywhere ashore. Dim phenomena such as comet tails especially need dark skies when observing with the naked eye — just imagine seeing them during the new moon and a thousand miles away from the nearest city lights!
AstroCruises (TM) has two comet cruises scheduled in 2004. The first coincides with the period that both comets are expected to brighten from fourth-magnitude to first-magnitude, and at the time Comet Q4 (NEAT) will only be easily seen in the southern hemisphere. The second comet cruise will coincide with Comet Q4 (NEAT)'s best appearance.
Southern Hemisphere Double Comet Cruise
Our Southern Hemisphere Double Comet Cruise April 6-May 2, 2004, is aboard Crystal Serenity and sails from Cape Town to Ft. Lauderdale, and at a time that the comets are expected to brighten to easy naked-eye visibility and the nights are the darkest (new moon is April 19). You might also see all 21 first-magnitude stars in one night and qualify for 21 Club, and see the 26 new constellations created when European astronomers first charted the stars of the southern hemisphere. Embarkation is from Cape Town, South Africa on Wednesday, April 7, after a night in Cape Town and the itinerary is Walvis Bay, Namibia; Jamestown, St. Helena; Rio de Janeiro, Salvador, Brazil; Bridgetown, Barbados; and Road Town, Tortola, British Virgin Islands. It arrives in Ft. Lauderdale Sunday, May 2, with an optional disembarkation in New York on May 5. Ocean-view staterooms start at $11,145* ppdo (per person, double occupancy), and includes port charges of $430, $200 onboard credit, AstroCruises astronomy kit and exclusive Virtuoso Voyager Club shore excursions scheduled in Rio de Janeiro and Barbados. This is a significant saving from the published fares of $18,290* ppdo to $60,835* ppdo. A Brazilian tourist visa required for U. S. citizens. Please contact us for the current best AstroCruises (TM) deal.
Comet Q4 (NEAT) in early April will be visible in the southern hemisphere, predicted to brightening from fourth magnitude, and can be seen late into the night and again before dawn — even all night long from far enough south. The comet brightens to first magnitude and is visible in the northern hemisphere by the time this cruise reaches Ft. Lauderdale. The chart below shows the height above the horizon of the comet at nautical twilight, that point of darkness when the sun is 12 degrees below the horizon and you can't tell the sea from the sky at the horizon.
Comet Q4 (NEAT) on CRYSTAL SERENITY Comet Cruise April 6-May 2
| Date | Port | Comet
Rises | Comet
Altitude
as NT Begins | Nautical
Twilight
Begins | Nautical
Twilight
Ends | Comet
Altitude
as NT Ends | Comet
Sets | Comet
Magnitude |
|---|
| April 7 (Wed.) | Cape Town | up all night | 25 | 6:08 a.m. | 7:28 p.m. | 29 | up all night | 4.1 |
| April 9 (Fri.) | Walvis Bay | 1:22 | 21 | 5:24 a.m. | 5:54 p.m. | 25 | 11:48 p.m. | 3.9 |
| April 12 (Mon.) | St. Helena | 4:25 a.m. | 6 | 5:43 a.m. | 7:03 p.m. | 15 | 9:55 p.m. | 3.6 |
| April 18 (Sun.) | Rio de Janeiro | 3:01 a.m. | 9 | 5:18 a.m. | 6:26 p.m. | 26 | 11:42 p.m. | 2.9 |
| April 21 (Wed.) | Salvador | 5:40 a.m. | below horizon | 4:54 a.m. | 6:11 p.m. | 21 | 9:21 p.m. | 2.5 |
| April 27 (Wed.) | Bridgetown | 10:13 a.m. | below horizon | 4:52 a.m. | 7:01 p.m. | 6 | 7:54 p.m. | 1.7 |
| April 29 (Fri.) | Road Town | 11:09 a.m. | below horizon | 5:03 a.m. | 7:29 p.m. | 7 | 8:22 p.m. | 1.4 |
Comet T7 (LINEAR) should be visible in some latitudes from mid-April to mid-June. In the two weeks between the April 5th full moon and April 19th new moon the comet is predicted to brighten from third to second magnitude, rise earlier before nautical twilight and appear higher in the early morning sky. The comet brightens to first magnitude by the time this cruise reaches Ft. Lauderdale.
Comet T7 (LINEAR) on CRYSTAL SERENITY Comet Cruise April 6-May 2
| Date | Port | Nautical
Twilight
Begins | Comet
Altitude
at NT | Comet
Rises | Comet
Magnitude |
|---|
| April 7 (Wed.) | Cape Town, South Africa | 6:08 a.m. | 2 | 5:56 a.m. | 3.5 |
| April 9 (Fri.) | Walvis Bay, Namibia | 5:24 a.m. | 6 | 4:55 a.m. | 3.3 |
| April 12 (Mon.) | Jamestown, St. Helena | 5:43 a.m. | 10 | 4:55 a.m. | 3.0 |
| April 18 (Sun.) | Rio de Janeiro, Brazil | 5:18 a.m. | 16 | 4:05 a.m. | 2.5 |
| April 21 (Wed.) | Salvador, Brazil | 4:54 a.m. | 20 | 3:30 a.m. | 2.4 |
| April 27 (Tue.) | Bridgetown, Barbados | 4:52 a.m. | 19 | 3:31 a.m. | 1.8 |
| April 29 (Thu.) | Road Town, Tortola | 5:03 a.m. | 18 | 3:46 a.m. | 1.7 |
| May 2 (Sun.) | Ft. Lauderdale, Florida | 5:49 a.m. | 14 | 4:46 a.m. | 1.5 |
Mediterranean Comet Cruise
Our Mediterranean Comet Cruise May 9-16, 2004, is aboard Seabourn Legend and sails from Rome (Civitavecchia) to the French Riviera at a time when skies are typically clear, and at a time that the waning moon brings darker skies (and better stargazing) nightly. Embarkation is from Civitavecchia on Sunday, May 9, and the itinerary is Porto Cervo, Sardinia; La Goulette (Carthage/Tunis), Tunisia; Palermo, Sicily; Sorrento, Italy; Porto Vecchio, Corsica; and Monte Carlo, Monaco. It arrives in Nice, France, on Sunday, May 16. Ocean-view staterooms start at $3995* ppdo (per person, double occupancy), and includes port charges, government fees and even gratuities. This is a significant saving from the published fares of $6,125* ppdo to $16,415* ppdo. Please contact us for the current best AstroCruises (TM) deal.
Comet Q4 (NEAT) is predicted at first-magnitude until the end of the Mediterranean cruise, and each day throughout the cruise it appears higher above the horizon in the evening and for a longer period of time. At the end of nautical twilight the comet is almost a third of the way between the horizon and the point directly overhead at the beginning of the cruise, and by the the end of the cruise appears almost halfway between the horizon and the point directly overhead at the end of nautical twilight. Comet T7 (LINEAR) is not well positioned for observation in the northern hemisphere in early and mid-May.
SEABOURN LEGEND Comet Q4 (NEAT) Cruise May 9-16
| Date | Port | Nautical
Twilight
(NT) Ends | Comet
Altitude
at NT | Comet
Sets | Comet
Magnitude |
|---|
| May 9 (Sun.) | Civitavecchia (Rome) | 9:23 p.m. | 26 | 11:50 p.m. | 1.0 |
| May 10 (Mon.) | Porto Cervo, Sardinia | 9:38 p.m. | 29 | 12:20 a.m. | 1.0 |
| May 11 (Tue.) | La Goulette, Tunisia | 9:20 p.m. | 34 | 12:33 a.m. | 1.1 |
| May 12 (Wed.) | Palermo, Sicily | 9:13 p.m. | 39 | 12:37 a.m. | 1.2 |
| May 13 (Thu.) | Sorrento, Italy | 9:20 p.m. | 39 | 12:53 a.m. | 1.3 |
| May 14 (Fri.) | Calvi, Corsica | 9:51 p.m. | 40 | 1:40 a.m. | 1.4 |
| May 15 (Sat.) | Monte Carlo, Monaco | 10:05 p.m. | 41 | 2:05 a.m. | 1.5 |
| May 16 (Sun.) | Nice, France | 10:06 p.m. | 43 | 2:20 a.m. | 1.5 |
Other Comet Information
Moonlight
Moonlight can interfere with pre-dawn stargazing when it is waning (between full moon and new moon) and can interfere with evening stargazing when it is waxing (between new moon and full moon). Except for the new moon, which crosses the sky in the daytime unlit and unseen, the best time for pre-dawn stargazing is during the waxing crescent (between new and first quarter) moon and the best time for evening stargazing is during the waning crescent (between last quarter and new) moon. The rise/set times in the following chart are approximate and apply for standard time, one hour behind daylight-saving or summer time.
Moon Phases
New Moon
(Rises at Sunrise,
Sets at Sunset) | First Quarter Moon
(Rises at Noon,
Sets At Midnight) | Full Moon
(Rises at Sunset,
Sets at Sunrise) | Last Quarter Moon
(Rises at Midnight,
Sets at Noon) | New Moon
(Rises at Sunrise,
Sets at Sunset) |
|---|
| | | April 5 | April 12 | April 19 |
| April 19 | April 27 | May 4 | May 11 | May 19 |
| May 19 | May 27 | June 3 | June 9 | June 17 |
Details for Comet C/2001 Q4 (NEAT)
Details for Comet C/2002 T7 (LINEAR)
General Comet Information
Specific Comet Information
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Last update: 10 December 2003
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