Seeing Stars with James Wooten: Five planets at dawn, leap day this February!

Star Map

Jupiter is now a late evening object, rising in the east. It rises by 9 p.m. on Feb. 1, and by Feb. 29 it comes up just before 7 p.m., which is during evening twilight. Jupiter comes to opposition on March 8, which is when Earth aligns with Jupiter and the Sun. That is why Jupiter is up all night long in late February and early March.

As dawn approaches this month, Jupiter will still be visible, this time high in the west.  Meanwhile, the four other visible planets will have risen as well. That’s right, February 2016  features all five naked-eye planets at dawn!

Venus is in the southeast at dawn. You can’t miss it, as Venus outshines all the stars we see at night, and in fact outshines everything but the Sun and the Moon.

Mars is in the south at dawn. Noticeably reddish in tint, Mars continues to brighten each day until its opposition next spring. 

Saturn is in the south southeast at dawn, above the distinctive pattern of Scorpius, the scorpion. Mars slowly approaches Saturn this month.

Mercury is the biggest challenge to find. This month, though, Mercury is very close to Venus and to its left. Thus, once you find Venus, the brightest dot to its left is Mercury. 

Mercury is the first planet to leave the gathering as it heads back towards the Sun late this month. The cutoff date of Feb. 20 is somewhat arbitrary, though. It’s better to watch the sky and, using Venus as your guide, see for yourself when is the last day you can still see Mercury before losing it the Sun’s glare. The next to leave is Jupiter, which shifts into the evening sky after opposition. 

Taurus, the Bull, is high in the south. Look for the Pleiades star cluster above reddish Aldebaran. Dazzling Orion, the Hunter, takes center stage on winter evenings.  Surrounding Orion are the brilliant stars of winter. Orion’s belt points down to Sirius, the Dog Star, which outshines all other stars we ever see at night. The Little Dog Star, Procyon, rises with Sirius and is level with Orion’s shoulder as they swing towards the south. To the upper left of Orion’s shoulder is Gemini, the Twins.

Under Sirius and low to the southern horizon this month is a star that most Americans never get to see—Canopus. Representing the bottom (keel) of the legendary ship Argo, Canopus is the second brightest star ever visible at night. Thus, it is clearly noticeable along the southern horizon on February and March evenings. However, you must be south of 37 degrees north to see Canopus rise. (This is the line that divides Utah, Colorado, and Kansas from Arizona, New Mexico, and Oklahoma.)

The sky we see depends on our latitude as well as on the time of night and time of year.  From any given location in our hemisphere, there is an area of the sky around the North Star in which stars never set (circumpolar stars), and an equivalent area around the South Celestial Pole in which stars never rise. The closer you are to the pole, the larger these areas are. The closer you get to the equator, the fewer circumpolar stars there are, but there are also fewer stars that never rise for you. At the equator, no stars are either circumpolar or never visible; all of them rise and set as Earth turns. 

That’s why, down here in south Texas, the Big Dipper sets for a while although it’s always up for most Americans. On the other hand, Canopus, too far south to rise for most Americans, rises for us.

Moon Phases

Moon Phases in February 2016:

Last Quarter: Jan. 31, 9:28 p.m.

New: Feb. 8, 8:39 a.m.

First Quarter: Feb. 15, 1:46 a.m.

Full: Feb. 22, 12:20 p.m.

(February is so short that last quarter Moons occur on Jan. 31 and March 1, but not in February). 

The New Moon of Feb. 8 is the second New Moon after the winter solstice. Accordingly, it marks Chinese New Year. Welcome to the Year of the Monkey!

Monday, Feb. 29, is leap day. This day exists because our normal year of 365 days is too short. The true length of one Earth orbit around the Sun is 365 days and almost 6 hours.  No one wants to begin a year in the middle of a day, however. Therefore, we let the error add up over four years, until it becomes 24 hours, or one whole day, then add that day back to the calendar. Thus, February 29 occurs every four years. 

Almost 6 hours?  Well, alright, the difference between our orbit and our year is actually 5 hours, 49 minutes, and 16 seconds. That makes our system a very slight overcorrection.  To prevent that from adding up, we’ll skip leap day in 2100, 2200, and 2300. 

On most clear Saturday nights at the George Observatory, you can hear me do live star tours on the observation deck with a green laser pointer. If you’re there, listen for my announcement. 

Clear Skies!

Seeing Stars with James Wooten: Springing forward into Daylight Saving Time

This star map shows the Houston sky at 9 pm CST on March 1, 9 pm CDT on March 15, and 8 pm on March 31. To use the map, put the direction you are facing at the bottom. Jupiter is high overhead in Gemini, the Twins. Dazzling Orion, the Hunter is to the Twins’ lower right. To Orion’s left are the two Dog Stars—little dog Procyon and big dog Sirius. Sirius outshines all other stars we see at night. In the north, the Big Dipper is higher in the sky. Leo, the Lion, rises in the east. These stars, along with Arcturus, announce the coming spring. Mars now rises in late evening.

This star map shows the Houston sky at 9 p.m. CST on March 1, 9 p.m. CDT on March 15, and 8 p.m. on March 31. To use the map, put the direction you are facing at the bottom. Jupiter is high overhead in Gemini, the Twins. Dazzling Orion the Hunter is to the Twins’ lower right. To Orion’s left are the two Dog Stars: little dog Procyon and big dog Sirius. Sirius outshines all other stars we see at night. In the north, the Big Dipper is higher in the sky. Leo, the Lion, rises in the east. These stars, along with Arcturus, announce the coming spring. Mars now rises in late evening.

This month, Jupiter remains well placed for evening observing all winter and spring. Look for it almost overhead at dusk and high in the west later in the evening.

Mars remains in the morning sky. It continues to brighten a bit in the south at dawn. Later in March, it also begins rising in late evening (9:30 p.m. on March 5; 8:20 p.m. on March 31)

Saturn remains in the pre-dawn sky. Face south immediately before sunup to see it.

Venus has now entered the morning sky. Look southeast at dawn for the brightest point of light there; only the Sun and Moon outshine Venus. Venus remains a morning star for almost all of 2014.

Brilliant winter stars shift toward the southwest during March. Dazzling Orion is almost due south at dusk. His three-starred belt is halfway between reddish Betelgeuse and bluish Rigel. Orion’s belt points up to Aldebaran in Taurus the Bull. This winter and spring, the Bull also contains Jupiter. To Orion’s upper left are the twin stars Castor and Pollux, marking the heads of Gemini, the Twins. You can find Sirius, the brightest star we ever see at night, by drawing a line from Orion’s belt towards the horizon. To Orion’s left, about level with Betelgeuse, is Procyon, the Little Dog Star.

From Sirius, look a little bit to the right and then straight down to the horizon. If your southern horizon is clear of clouds and tall earthly obstacles, you’ll see Canopus, the second brightest star ever visible at night. This star is so far south that most Americans never see it, and many star maps made in the USA omit it. (You must be south of 37 degrees north — the latitude of the USA’s Four Corners — for Canopus to rise). As you view Canopus, keep in mind that the sky we see depends on our latitude as well as on time of year and time of night.

Joining the winter stars are stars of spring rising in the east. Look for Leo the Lion at dusk. Later in the evening, extend the Big Dipper’s handle to “Arc to Arcturus” and then “speed on to Spica;” these stars rise at about 10 p.m. in early March, but by 9 p.m. on the March 31.

Moon Phases in March 2014:
New:
March 1, 2:02 a.m.; March 30, 1:47 p.m.
1st Quarter: March 8, 7:26 a.m.
Full: March 16, 12:10 p.m.
Last Quarter: March 23, 8:47 p.m.

Sun., Mar. 9, is the second Sunday of the month. Accordingly, Daylight Saving Time begins at 2 am that morning. (The time goes from 1:59:59 to 3:00:00, with the 2 a.m. hour skipped.) Don’t forget to set your clocks forward one hour!

At 11:57 am on Thurs., Mar. 20, the Sun is directly overhead at the equator. That makes this the vernal equinox, one of two days when everyone on the planet has the same amount of daylight. Many consider this the ‘official’ start of spring. That’s because for us, days have been lengthening, with the Sun slightly higher in the sky each day, from December until now. After March 20, days continue to lengthen, making day longer than night. In the Southern Hemisphere, their long summer days have been shortening until now, with the Sun lower in the sky each day. After March 20, they continue to shorten, making day shorter than night. For them, then, this is the autumnal equinox.

On most clear Saturday nights at the George Observatory, you can hear me do live star tours on the observation deck with a green laser pointer. If you’re there, listen for my announcement.

Clear Skies!

(Click here for the HMNS Planetarium Schedule)

Go Stargazing! May Edition

Saturn is the only planet in May 2011 evening skies.  Face south southeast at dusk, and you’ll see Saturn near a star of similar brightness— Spica in Virgo.  Saturn is significantly higher in the sky than Spica and a bit to its right as you face south.  Last month, Earth passed between the Sun and Saturn.  That alignment, called opposition, put Saturn in the sky all night long.  The ringed planet is now well placed for evening viewing, and remains in the evening sky until late September 2011.

mars-06-crop
Mars
Creative Commons License photo credit: chipdatajeffb

The other four naked eye planets are involved in a very close gathering low in the east at dawn.  You will need a clear view all the way to the east northeastern horizon at daybreak to observe this planet massing.  However, the planets do outshine all stars in this general area. If you’re able to observe any points of light just above the horizon as dawn begins, you’re probably seeing the planets.  As of now, Venus and Mercury rise first, with Mercury about a degree under the brighter Venus.  Mars and Jupiter are a bit to their lower left, with Mars a little to the left of Jupiter.  Mars was less that half a degree above Jupiter on May 1, and is now slowly pulling away from it.  Venus and Mercury are moving faster, so they are closing the gap on Mars and Jupiter.

On the morning of May 11, Venus and Mercury will be aligned with Jupiter, with Venus less than one degree from Jupiter.  This is also when the entire grouping is the most compact, with all four planets within six degrees of one another.  By May 21, Mercury and Venus will have caught up with Mars, with Venus just over a degree from the red planet.  After this, Mercury and Venus pull ahead of Mars and thus go deeper into the sun’s glare.  Mars and Jupiter, left behind, remain in the morning sky all summer.

Star Gazing
Creative Commons License photo credit: jurvetson

A swath of brilliant winter stars sets in the west at dusk this month.  Orion, the Hunter, is still visible in the west as May begins.  His two dogs, represented by Sirius and Procyon, are to his left.  To Orion’s right is Taurus, the Bull, with the star Aldebaran as its eye. Gemini, the Twins, are above Orion.  The Big Dipper is above the North Star, with its handle pointing to the right.  From that handle, you can ‘arc to Arcturus’ and then ‘speed on to Spica;’ those stars are in the east and southeast at dusk.  Leo, the Lion, passes almost overhead in late evening.

As Orion and Taurus set, look for Antares, brightest star of Scorpius, the Scorpion, to rise in the southeast.  At the same time, Vega, brightest star of the Summer Triangle, appears low in the northeast.  These stars remind us that summer is on the way.

Moon Phases in May 2011:

New Moon                              May 3, 1:50 a.m.

1st Quarter                             May 10, 3:32 p.m.

Full Moon                               May 17, 6:07 a.m.

Last Quarter                          May 24, 1:51 p.m.

Go Stargazing: April Edition

Saturn dominates April 2011 skies because yesterday, on April 3, the Earth passed between the sun and Saturn.  This alignment, called opposition, puts Saturn in the sky all night long; it rises in the east at dusk and sets in the west at dawn.

Venus’ apparition as a dazzling morning star is coming to an end.  It is getting lower and lower in the sky each morning as the angle between the solar system plane and the horizon gets shallower.  Face southeast at dawn, and you can’t miss it of you have a clear horizon.

Jupiter is directly behind the sun from our perspective on April 6 and therefore invisible all month.

Mars also remains lost in the sun’s glare all month.

A swath of brilliant winter stars continues to dominate evening skies.  These stars are now high in the west at dusk and set in late evening.  Orion, the Hunter, is in the southwest as April begins.  His two dogs, represented by Sirius and Procyon, are to his left.  Beside Orion in the west is Taurus, the Bull with Aldebaran as its eye. Gemini, the Twins, are above Orion.  The Big Dipper is to the upper right of the North Star, with its handle pointing down and to the right.  From that handle, you can ‘arc to Arcturus’ and then ‘speed on to Spica’; those stars are low in the east at dusk.  Leo, the Lion, passes almost overhead in late evening.

Below Sirius, just above the southern horizon in late twilight, is a star second only to Sirius in brightness.  This is Canopus, which marks the keel (bottom) of the legendary ship Argo Navis.  Canopus is so far south, in fact, that most Americans never see it.  From the Gulf Coast, however, Canopus does rise.  In early April, you can still see it in the evening just after dusk.

Lune
Creative Commons License photo credit: ComputerHotline

Moon Phases in April 2011:

New Moon                      April 3, 9:32 a.m.

1st Quarter                     April 11, 7:05 a.m.

Full Moon                       April 17, 9:43 p.m.

Last Quarter                  April 24, 9:46 p.m.

Sunday, April 24, is the first Sunday after the first Full Moon of spring.  Therefore, this is Easter Sunday.  This happens to be the second latest possible date for Easter.  Easter will fall on April 25, the absolute latest date, in 2038.