About James

James is the Planetarium Astronomer at the Houston Museum of Natural Science. He teaches students every school morning in the planetarium, and also answers astronomy questions from the public.

Seeing Stars with James Wooten: The Stars of Spring are Rising

March star report
Mars remains in the west at dusk this month as it moves through Pisces. Mars continues to fade a little each night as Earth continues to leave it farther behind. After this month, Mars begins to be lost in the glare of the Sun.

Venus is in the west at dusk. Venus overtook Mars on February 21; now watch Venus leave behind the much dimmer Mars throughout March.

Jupiter was up all night long in February; now it is high in the east as soon as night falls. Jupiter outshines all stars we ever see at night, so it will be obvious in the east at dusk.

Saturn is in the south at dawn.

Brilliant winter stars shift towards 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. 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 10:00 in early March but by 9pm on the 31st.

full-moon-21

Moon Phases in March 2015:

Full March 5, 12:05 pm
Last Quarter March 13, 12:48 pm
New March 20, 4:38 am
1st Quarter March 27, 2:43 am

Sunday, March 8, is the second Sunday of the month. Accordingly, Daylight Saving Time begins at 2:00 am on that date. (Officially, the time goes from 1:59 to 3:00 am). Don’t forget to spring forward!

At 5:45 pm on Friday, March 20, the Moon is directly overhead at the equator. This is therefore the vernal equinox. On this date everyone on Earth has the same amount of daylight and the same amount of night. The common statement that day equals night on this date would be true if the Sun were a point in our sky. Since the Sun is a disk about half a degree across in our sky, day is slightly longer than night on the equinox. For us, this is the ‘official’ start of spring; our days will continue to lengthen until the longest days of June usher in summertime. Below the equator, it is autumn, and days will continue to shorten until winter begins in June.

The New Moon of March 20 blocks the Sun, casting its shadow on the Earth. This results in a solar eclipse. Unfortunately, the shadow traces a path in the North Atlantic between Iceland and Scandinavia, making the eclipse inaccessible to us.

Click here for the full Planetarium Schedule

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.

Seeing Stars With James Wooten: Celestial rarity, Canopus appears this month

Star Chart - Feb 15 This star map shows the Houston sky at 9 pm CST on February 1, 8 pm CST on February 14, and dusk on February 28. To use the map, put the direction you are facing at the bottom. Taurus, the Bull, is almost overhead. Dazzling Orion, the Hunter is high in the south, with his two dogs behind him. Sirius, the Big Dog Star, is the brightest star we ever see at night. Look for Canopus on the southern horizon below Sirius. Jupiter, in Cancer, is up almost all night long in early February. In the north, the Big Dipper has re-entered the evening sky. Venus and Mars are less than one degree apart on the 21st.[/caption]

This month, Mars remains in the southwest at dusk this month as it moves through Aquarius. Mars continues to fade a little each night as Earth continues to leave it farther behind.

Venus is low in the southwest at dusk. Watch Venus approach the much dimmer Mars, until they are less than one degree apart on February 21.

Jupiter is up all night long on February 6. That’s when Earth passes between the Sun and Jupiter, an alignment called ‘opposition’. At opposition Jupiter rises at sundown and sets at sunrise. Jupiter outshines all stars we ever see at night, so it will be obvious in the east at dusk and in the west at dawn.

Saturn is in the south southeast at dawn.

In February, the Big Dipper only partly risen at dusk.  Its two pointer stars—the stars farthest from the handle which point at the North Star, may be high enough to see over trees and buildings.

Taurus, the Bull is now 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 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 in February 2015:
Full                               February 3, 5:10 pm
Last Quarter                  February 11, 9:52 pm
New                              February 18, 5:49 pm
1st Quarter                    February 28, 11:15 am

The New Moon of February 18 is the second New Moon after the winter solstice.  Accordingly, it marks Chinese New Year. The Year of the Horse ends and the Year of the Sheep begins.

Click here for the Burke Baker Planetarium schedule. 

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.

 

Seeing Stars with James Wooten: See Comet Lovejoy this month, get a once-in-a-lifetime treat!

Star Chart - january 2015

This month, Mars remains in the southwest at dusk this month as it moves through Aquarius. Mars continues to fade a little each night as Earth continues to leave it farther behind. 

Jupiter is now up most of the night. It rises now at about 8:25, and by January 31 it will rise in evening twilight. Jupiter outshines all stars we ever see at night, so it will be obvious once it rises.   

Venus has emerged from the Sun’s glare, and is low in the southwest at dusk. Look for Venus to appear higher in the evening sky in the weeks to come.

Mercury is to the lower right of Venus in the southwest at dusk, but only for a little while.  The two are less than one degree apart January 8-12 (Venus is much brighter). After mid-month, we’ll see it head back towards the Sun and drop out of view. 

Saturn is in the southeast at dawn.

In January, the Big Dipper only partly risen at dusk. As the Big Dipper rises, though, Cassiopeia remains high. This is a pattern of five stars in a distinct W (or M) shape which lies directly across the North Star from the Big Dipper. Look for Cassiopeia high in the north on fall and winter evenings.  

Watch for the Great Square of Pegasus in the west at dusk. 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.

Also this month: Look for comet Lovejoy! 

Discovered in August 2014, Lovejoy now passes close enough to Earth for us to see. On January 7, the comet makes its closest approach to Earth — about 0.47 AU (a little less than half the Earth-Sun distance. However, Lovejoy is still falling in towards the Sun as it passes Earth; perihelion isn’t until January 30. As a result, it should continue to brighten slightly even after the 7th as it gives off more gas and dust during its approach to the Sun. 

Here is Sky and Telescope’s Lovejoy finder chart for this month. Note that you’ll find Lovejoy high in the evening sky to the west (right as you face south) of the bright pattern Orion, the Hunter. What’s more, the Moon, now past full, moves out of the picture right as Lovejoy is shifting northward in our sky, thus appearing higher each evening. Thus, if you are able to go far from city lights, you can see Lovejoy dimly with the unaided eye.  Observers are reporting a bluish/greenish glow, indicating that Lovejoy is producing little dust and that the gas tail dominates (dust would reflect sunlight, making the comet look whiter).

Our only chance to see this particular comet comes this month; once it’s gone it won’t be back for 8,000 years!

Moon Phases in January 2015:

Full: January 4, 10:53 p.m.
Last Quarter: January 13, 3:46 a.m.
New: January 20, 7:14 a.m.
1st Quarter: January 28, 10:48 p.m. 

At 1 a.m. on Sunday, January 4, the Earth came as close to the Sun as it will for the whole year. This was perihelion. 

Although the winter solstice is the shortest day, the earliest sunset occurred on about December 2, and the latest sunrise will occur January 10.

That’s because the Earth speeds up on its orbit as it approaches perihelion (closest approach to the Sun). This acceleration shifts sunrise, local noon, and sunset slightly later each day for the first part of this month.  The effect is smaller than that of the Sun taking a lower path across the sky, which normally dominates in causing earlier sunsets and later sunrises. But the Sun’s apparent path varies very little near the solstice itself, allowing the secondary effect of the Earth approaching the Sun to predominate until mid-January.  Most people, then, will notice that both sunrise and sunset are now happening earlier than in December. As we move farther from the solstice, the effect of the Sun taking a slightly higher path each day again predominates. 

Click here for the Burke Baker Planetarium Schedule. 

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: A solstice and a shower for December

This star map shows the Houston sky at 9 pm CST on December 1, 8 pm CST on December 15, and dusk on December 31.  To use the map, put the direction you are facing at the bottom. The Summer Triangle sets in the west.  This consists of the brightest stars in Cygnus, Lyra, and Aquila.  Mars outshines all the dim stars in the southwest.   Pegasus, the Flying Horse, is high in the south.  To the east, we see Orion, the Hunter, and Taurus, the Bull, finally entering the sky.  The brilliant stars of winter began their grand entry.

This star map shows the Houston sky at 9 pm CST on December 1, 8 pm CST on December 15, and dusk on December 31. To use the map, put the direction you are facing at the bottom.
The Summer Triangle sets in the west. This consists of the brightest stars in Cygnus, Lyra, and Aquila. Mars outshines all the dim stars in the southwest. Pegasus, the Flying Horse, is high in the south. To the east, we see Orion, the Hunter, and Taurus, the Bull, finally entering the sky. The brilliant stars of winter began their grand entry.

This month, Mars remains in the southwest at dusk this month as it moves through Capricornus. Mars continues to fade a little each night as Earth continues to leave it farther behind. 

Jupiter is now high in the south at dawn; it is the brightest thing there. 

Venus begins to emerge from the Sun’s glare late this month. Can you spot it low in the southwest at dusk by New Year’s Eve?

Saturn begins to emerge into the morning sky by mid-month. Look low in the southeast at dawn.

In December, the Big Dipper is below the horizon at dusk. As the Big Dipper sets, though, Cassiopeia is high above the North Star. This is a pattern of five stars in a distinct M or W shape. Look for Cassiopeia high in the north on fall and winter evenings.  

The Summer Triangle sets in the west.  Watch for the Great Square of Pegasus almost overhead at dusk now and in the west by Christmas. Taurus, the Bull rises in the east.  Look for the Pleiades star cluster above reddish Aldebaran. Dazzling Orion, the Hunter rises shortly after dusk (by month’s end, it is already up at dusk). As Orion enters the evening sky, we transition from the relatively dim evening skies of autumn to the brilliant stars of winter. We are beginning to face away from the center of the galaxy, looking at stars behind us in our own part (the Orion Spur) of our galaxy.

Moon Phases in December 2014:

Full: December 6, 11:26 am
Last Quarter: December 14, 11:53 am
New: December 22, 12:35 am
1st Quarter: December 28, 5:32 pm

At 10:03 pm on Sunday, December 21, the Sun is directly overhead at the Tropic of Capricorn, the farthest point south where this is possible. This puts the Sun as low as possible in our sky, and marks the winter solstice. In the Southern Hemisphere, the Sun is as high as possible in the sky—this is the summer solstice for them. 

Although the winter solstice is the shortest day, the earliest sunset occurred on about December 2, and the latest sunrise will occur January 10.

That’s because the Earth speeds up on its orbit as it approaches perihelion (closest approach to the Sun) next month. This acceleration shifts sunrise, local noon, and sunset slightly later each day this month and next. The effect is smaller than that of the Sun taking a lower path across the sky, which normally dominates in causing earlier sunsets and later sunrises. But the Sun’s apparent path varies very little near the solstice itself, allowing the secondary effect of the Earth approaching the Sun to predominate. For most people, then, (those who witness sunset but sleep through sunrise), days will seem to lengthen throughout December, although they don’t really begin lengthening until December 21.

The Geminid Meteor Shower peaks this month, as it does every December. Along with the Perseids in August, the Geminids are one of the two most reliable meteor showers, producing on average about 100 meteors per hour. 

The Geminids are unique among meteor showers because they are associated not with a comet but with an asteroid, 3200 Phaethon. This means that with Geminids, we see significant activity much earlier in the night than with other showers. Most meteor showers peak in the hours immediately before dawn. This is because what plows through the debris field is the leading edge of the Earth, and that’s the side going from night into day.  Since Phaethon is an asteroid, however, debris along its orbital path forms a shallower angle to Earth’s orbital path, meaning that we begin to face into the debris field as early as 9 or 10 pm. Meteors will seem to ‘radiate’ from the constellation Gemini, hence the name of the shower. However, they may appear anywhere in the sky. 

As always, you see more meteors the farther you are from big city lights which hide dimmer ones. Our George Observatory will be open from 5pm to midnight Saturday night, December 13 for observing this meteor shower. Midnight is about when the Moon, approaching last quarter phase, will rise.

Click here for the Burke baker Planetarium Schedule.

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!