Saturday, June 11, 2016

Transcript for June 19th to 25th

RACHEL
Welcome to Idaho Skies for the third week of June. We’re your hosts, Rachel...

PAUL
...and Paul.

RACHEL
The moon is close to Saturn on the night of the 18th and morning of the 19th.

PAUL
That night, Saturn appears as the yellow-white star to the moon’s lower right.

RACHEL
You’ll need at least a spotting scope or small telescope to see its rings and largest satellite, Titan.

PAUL
Your telescope needs a magnification of at least 25 power.

RACHEL
In a telescope, Titan will appear as a star to Saturn’s lower left on the 18th and 19th.

PAUL
Titan rapidly changes its position with respect to Saturn each night.

RACHEL
The reason for the rapid change is that it only takes Titan 16 days to orbit Saturn.

PAUL
Which is only half as long as it takes the moon to orbit Earth.

RACHEL
Titan is perpetually cloud covered.

PAUL
Sadly, that means there’s no majestic view of Saturn in Titan’s sky.

RACHEL
Only a hazy pumpkin-colored sky.

PAUL
If Saturn were visible on Titan however, the planet would appear 10 times larger than our moon appears to us.

RACHEL
Late on the 19th and after midnight on the 20th you’ll find lots of nebulae and star clusters strewn about the moon’s left side.

PAUL
Star clusters and nebulae are concentrated in this part of the sky because it’s towards our galaxy’s stellar-rich center.

RACHEL
But don’t worry if you can scan this region with binoculars on the 20th.

PAUL
Because you’ll find the same region to the moon’s right on the 21st.

RACHEL
The moon is full on the 20th.

PAUL
The full moon in June is often called the Strawberry Moon.

RACHEL
It’s also the Summer Solstice on the 20th.

PAUL
Hey, that means it’s the first day of summer.

RACHEL
Did you know that solstice means sun standing still?

PAUL
I did.

RACHEL
It gets this name because when you watch the sun’s setting location on the horizon, it appears to stop moving around this time of the year.

PAUL
In fact, around the day of the solstice, the sun sets its farthest position north.

RACHEL
Also on the first day of summer, the length of day is its longest and the night it’s shortest.

PAUL
But that’s not the same thing as the earliest sunrise or latest sunset.

RACHEL
The earliest sunrise occurs about a week earlier than the solstice and the latest sunset occurs a week later.

PAUL
Capricornus the Sea-goat is a large constellation.

RACHEL
But it’s not made up of very bright stars.

PAUL
That means it easier to locate when the moon passes through it.

RACHEL
And that happens on the night of the 23rd.

PAUL
Go to a dark location if you want to find Capricornus.

RACHEL
Capricornus will look more like a big grin than it does a mix of goat and fish.

PAUL
And the moon is located on the upper-right lip of Capricornus.

RACHEL
That’s Idaho Skies for the third week of June. Next week we’ll tell you about a lunar occultation that you can observe from Boise.

PAUL
Be sure to follow us on Twitter at Idaho Skies for this week’s event reminders and sky maps.

For Idaho Skies this is Paul...

RACHEL
...and Rachel.

PAUL
Dark skies and bright stars.

Transcript for June 12th to 18th

PAUL
Welcome to Idaho Skies for the second week of June. We're your hosts, Paul...

RACHEL
...and Rachel.

PAUL
The moon reaches first quarter on the 12th.

RACHEL
The first quarter moon appears as a half moon and it's the best phase for lunar observations.

PAUL
The reason why is that at first quarter, the boundary between lunar day and night faces directly towards Earth.

RACHEL
This gives the moon's morning shadows their longest apparent length.

PAUL
Long shadows bring out small changes in elevation.

RACHEL
In fact, elevation changes smaller than one hundred feet are visible on the moon when it's nearly 240,000 miles away.

PAUL
Spica, the brightest star in otherwise dim Virgo, is the bright pinpoint of light below the moon on the 14th.

RACHEL
Hey, can you make out the constellation of Corvus the Crow, which is further below Spica?

PAUL
It's the lop-sided square of four stars below and slightly right of Spica.

RACHEL
Corvus the Crow appears in the sky because the Greek god Apollo threw it into the sky during a fit of anger.

PAUL
Let that be a warning not to tell lies to Greek gods.

RACHEL
Mars is the orange beacon signaling you from a position below the moon on the night of the 16th.

PAUL
Mars was recently at opposition, so it's still relatively close to Earth.

RACHEL
But Mars is only half the diameter of Earth.

PAUL
Meaning it can be difficult to make out surface detail on this world even through a telescope.

RACHEL
While you can't see any Martian features through binoculars, you can split the double star that's located to the lower right of the moon.

PAUL
The star's name is Zubenelgenubi and its half the apparent distance from the moon as Mars.

RACHEL
The star appears as a significantly fainter white point of light when compared to Mars.

PAUL
Some people can split Zubenelgenubi into two stars with just their bare eyes, can you?

RACHEL
If not, then like the rest of us, you'll need to use binoculars.

PAUL
Late on the 17th and early on the 18th, the moon is just above the head of Scorpius the Scorpion.

RACHEL
The brightest star of Scorpius is Antares.

PAUL
Which is a super red giant star.

RACHEL
That's right. Red giant stars are stars nearing the end of their lives.

PAUL
That means someday soon, Antares will explode in a supernova explosion.

RACHEL
The explosion occurs when the core of the star stops fusing fuel into heavier elements and energy.

PAUL
Without its internal energy source, gravity makes the star's core collapse.

RACHEL
After the massive core squeezes itself into a neutron star, it rebounds slightly.

PAUL
The star's outermost layer is raining down as the core rebounds.

RACHEL
The impact between the falling outer layer and rebounding core creates a shockwave that rushes through the rest of the star.

PAUL
The result is a massive amount of fusion and titanic explosion that blows away the outer layer of the star.

RACHEL
In the fiery debris, fusion reactions create heavier elements like gold and platinum.

PAUL
That means the world's wealth of gold and platinum exists because of stars that died many billions of years ago.

RACHEL
That's Idaho Skies for the second week of June. Next week is the first day of summer.

PAUL
Be sure to read our blog for additional information. It's at idahoskies.blogspot.com.

For Idaho Skies this is Paul...

RACHEL
...and Rachel.

PAUL
Dark skies and bright stars.

Tuesday, May 31, 2016

Transcript for May 29th to June 4th

RACHEL
Welcome to Idaho Skies for the fifth week of May. We’re your hosts, Rachel…

PAUL
…and Paul.

RACHEL
The moon is last quarter on the 29th.

PAUL
Which means it’s also a nice to observe the moon through your binoculars.

RACHEL
More importantly, the moon has a neighbor that night and it’s a bit of an astronomical challenge to see.

PAUL
The challenge is our eighth planet, Neptune.

RACHEL
This icy giant planet is just 4.5 degrees away from the moon on the 29th.

PAUL
That means you can see both together in a pair of binoculars because binoculars typically have a field of view of 5 degrees.

RACHEL
You’ll need dark skies in order to see Neptune, so leave town for the countryside.

PAUL
Once in a dark location, place the moon on the right edge of your binoculars.

RACHEL
Then find the brightest star directly east of the moon and the far edge of your binoculars.

PAUL
A small distance farther east of the bright star is a faint star that will be as bright as Neptune.

RACHEL
And the distance between the star and the brighter star is the same distance Neptune is away from the bright star.

PAUL
Now Neptune is the other faint star down and slightly left of the bright star.

RACHEL
The bright star, its neighboring faint star, and Neptune will form a small triangle with a 90 degree apex centered on the bright star.

PAUL
It will be better to place the moon outside your view when you search for Neptune.

RACHEL
You’ll find a star map for you to use on both Idaho Skies on Twitter and Blog Spot.

PAUL
If you get a chance to see Neptune, remember that you’re looking at the most distant planet in the solar system.

RACHEL
The average distance between Earth and Neptune is 2.7 billion miles.

PAUL
At a diameter of 30,600 miles, Neptune is almost four times the size of Earth.

RACHEL
Its mass is 17 times greater than Earth.

PAUL
Why only 17 times more massive? Shouldn’t be more like four times four times four or 64 times more massive?

RACHEL
The reason for the discrepancy is that while Earth is rocky, Neptune is mostly water and gas. 

PAUL
The moon is close to the eastern horizon as you drive to work on the 31st.

RACHEL
Can you see Earthshine on the moon?

PAUL
Binoculars will definitely help.

RACHEL
But please don’t use your binoculars while you drive.

PAUL
It’s Saturn’s turn to reach opposition on June 3rd.

RACHEL
This means Earth is passing Saturn as the planets orbit around the sun.

PAUL
The reason Earth can pass the superior planets is because Earth’s orbit around the sun is smaller.

RACHEL
Smaller orbits are closer to the sun and therefore under the influence of a stronger gravitational field.

PAUL
Stronger gravitational fields mean orbital speeds must be higher to maintain a constant distance from the sun.

RACHEL
So if Earth wasn’t traveling faster, then it would spiral into the sun.

PAUL
Barbeque anyone?

RACHEL
That’s Idaho Skies for the last week of May. Next week is another opportunity to see Earthshine.

PAUL
Be sure to follow us on Twitter at Idaho Skies for this week’s event reminders and sky maps.

For Idaho Skies this is Paul…

RACHEL
…and Rachel.

PAUL
Dark skies and bright stars.

Monday, May 23, 2016

Transcript for May 22nd to 28th

PAUL
Welcome to Idaho Skies for the fourth week of May. We’re your hosts, Paul…

RACHEL
…and Rachel.

PAUL
Mars reaches opposition on the 22nd.

RACHEL
At opposition, superior planets…

PAUL
…or those beyond Earth…

RACHEL
…are at their closest to Earth for the year.

PAUL
Opposition occurs when the faster orbital motion of Earth results in it catching up to and passing the superior planet in question.

RACHEL
In the process of reaching opposition, superior planets appear to retrograde, or move slightly backwards across the stars.

PAUL
Retrograde motion is an illusion however.

RACHEL
It’s caused by the changing perspective between Earth and superior planets when compared to the fixed stars.

PAUL
Hundreds of years ago…

RACHEL
…that’s when the geocentric or Earth-centered solar system was in vogue…

PAUL
…astronomers and philosophers believed the superior planets actually moved backwards during a short period of time at retrograde.

RACHEL
This was possible because astronomers believed these planets orbited Earth in a set of nested orbits of various sizes.

PAUL
In the 16th century, Copernicus convinced astronomers otherwise.

RACHEL
He explained that retrograde motion was easier to understand when you move the sun to the center of the solar system and demoted Earth to a planet orbiting the sun.

PAUL
In time, other astronomers accepted this explanation, especially after the work of Johannes Kepler in the 17th century.

RACHEL
The bright yellowish star visible to the right of the moon on the 22nd is Saturn.

PAUL
You’ll need at a spotting scope or telescope capable of magnifying at least 25 times in order to see the planet’s rings.

RACHEL
And its largest satellite, Titan.

PAUL
Titan is a fascinating world.

RACHEL
Yes it is. It’s larger than Earth’s moon and cloaked in an atmosphere denser than Earth’s.

PAUL
Unfortunately, it’s also intensely cold on Titan.

RACHEL
How cold?

PAUL
So cold that methane, a gas used to heat our homes, is a liquid.

RACHEL
So cold that its nitrogen-rich atmosphere is almost cold enough to liquefy.

PAUL
Because of its dense atmosphere, Titan has weather.

RACHEL
However, its dense atmosphere prevents it weather from being as dynamic as Earth’s weather

PAUL
Still, this still allows it to rain on Titan.

RACHEL
On Titan, it’s a methane rain falling on rock hard pebbles of water ice.

PAUL
In 2005, the Huygens probe landed on Titan and returned images for 90 minutes.

RACHEL
Those images showed a landscape not too unlike Earth.

PAUL
Including mountains eroded by falling methane rain

RACHEL
And a stream bed where once a liquid methane stream once flowed.

PAUL
That’s Idaho Skies for the fourth week of May. We have a challenge for you next week, to see Neptune in your binoculars.

RACHEL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Rachel…

PAUL
…and Paul.

RACHEL
Dark skies and bright stars.

Monday, May 16, 2016

Transcript for May 15th to 21st

RACHEL
Welcome to Idaho Skies for the third week of May. We’re your hosts, Rachel…

PAUL
…and Paul.

RACHEL
The moon passes very close to Spica on the night of the 17th.

PAUL
Spica is the brightest star of Virgo the Maiden, which is the second largest constellation in the sky.

RACHEL
Only the constellation of Hydra is larger.

PAUL
Hydra is the constellation of the water snake and its located east of Virgo.

RACHEL
Virgo is made up of dim stars, so the constellation doesn’t stand out to the extent that its large size would indicate.

PAUL
One depiction of Virgo is as a goddess of justice named Justitia.

RACHEL
In this guise, she holds the scales of justice in her hands.

PAUL
And those scales are represented by the constellation of Libra the Scales.

RACHEL
So it’s not surprising that a widely spaced double star located in Libra can be found below the moon two days later on the 19th.

PAUL
The star’s name is Zubenelgenubi and the angular distance between the companion stars is wide enough that some people can see it as two separate stars without optical aid.

RACHEL
The rest of us need a pair of binoculars.

PAUL
You’ll find the double star 5 degrees below the moon on the night of the 19th.

RACHEL
So to find it, place the moon at the top of your binocular’s view.

PAUL
Then Zubenelgenubi will appear as the bright pair of stars at the bottom of your view.

RACHEL
The moon is full on the 21st.

PAUL
The full moon in May is called the Flower Moon by some people.

RACHEL
This year the Flower moon located between the planets Mars and Saturn.

PAUL
Mars is the bright orange-tinted star to the right of the moon.

RACHEL
And Saturn is the fainter yellow-white star to the lower left of the moon.

PAUL
Currently, there are five spacecraft orbiting Mars, three American, one European, and one Indian.

RACHEL
On Mars are two functioning rovers.

PAUL
They’re named Opportunity and Curiosity

RACHEL
Unfortunately, there’s only one spacecraft orbiting Saturn, Cassini.

PAUL
Below the moon is another orange star, Antares.

RACHEL
Antares is a red giant star and it represents the heart of Scorpius the Scorpion.

PAUL
Antares has the same color as Mars, but it’s not quite as bright as Mars these days.

RACHEL
That’s because Earth is approaching close to Mars.

PAUL
As Earth and Mars approach one another, Mars changes from an average orangish star into a bright orange beacon.

RACHEL
So when you observe Mars and Antares these days, look for their similar color but distinctly different brightness.

PAUL
That’s Idaho Skies for the third week of May. Mars reaches opposition next week and we’ll tell more about it.

RACHEL
Be sure to follow us on Twitter at Idaho Skies for this week’s event reminders and sky maps.

For Idaho Skies this is Rachel…

PAUL
…and Paul.

RACHEL
Dark skies and bright stars.

Monday, May 9, 2016

Transcript: May 8th to 14th

PAUL
Welcome to Idaho Skies for the second week of May. We’re your hosts, Paul…

RACHEL
…and Rachel.

PAUL
The moon reappears in the low west-northwest on the 8th.

RACHEL
It’s been absent from the sky for the last four days because it’s been too close to the sun.

PAUL
So after it gets dark after 10:00 PM on the 8th, look for the moon and see if you can detect Earthshine illuminating its dark portion.

RACHEL
Earthshine will be most visible if you view the moon through binoculars.

PAUL
You can make additional observations of Earthshine for several more nights.

RACHEL
Mercury made an evening appearance last month.

PAUL
However, it disappeared before the end of April.

RACHEL
This month Mercury passes between Earth and the sun and Idahoans get to see a part of that passage.

PAUL
This event is called a transit and it only happens on an average of 13 times per century.

RACHEL
The transit begins on the 9th at around 7:00 AM in Idaho and ends shortly after noon.

PAUL
Now a transit is not safe to observe directly with your eyes, since it requires looking at the sun.

RACHEL
This means that a telescope properly covered with solar viewing filters can directly observe the transit of Mercury, but other instruments cannot.

PAUL
Check the website for the Boise Astronomical Society for times and locations that you can see the transit.

RACHEL
Or try using the projection method of observing the sun.

PAUL
How can you project an image of the sun?

RACHEL
If you can aim a pair of binoculars, spotting scope, or small telescope at the sun, then you can project an image.

PAUL
Do NOT look at this image through the eyepiece.

RACHEL
Instead, place a sheet of white paper several inches to an foot away from the eyepiece of your scope or binoculars.

PAUL
Then focus the scope or binoculars until the image of the sun is sharp.

RACHEL
Any sunspots visible during the transit will appear irregularly shaped with fuzzy edges.

PAUL
While Mercury will appear as a tiny round dot with sharp edges.

RACHEL
Mercury will travel across the sun south of its equator from Earth’s perspective.

PAUL
But remember that if you observe the transit with a telescope, the image will be upside down.

RACHEL
Hey, want to see a really nice star cluster on the night of the 11th?

PAUL
The star cluster’s named is the Beehive Star Cluster and you’ll find it 7 degrees above the moon.

RACHEL
To see this attractive star cluster, point you binoculars at the moon and then tilt them directly north of the moon.

PAUL
Just after the moon leaves the binoculars’ view, the Beehive will appear at the top of the field of view.

RACHEL
You should see a striking similarity between the Beehive star cluster and a swarm of bees.

PAUL
What’s that bright star above the moon on the night of the 14th?

RACHEL
Why it’s Jupiter, the King of the solar system’s planets.

PAUL
Both are so close that you can see them both together in your binoculars.

RACHEL
You’ll notice that Jupiter is accompanied by a retinue of satellites.

PAUL
From left to right, the moons will be Callisto, Europa, Jupiter, and Ganymede.

RACHEL
There’s an even closer moon that you can see if you use a small telescope.

PAUL
It’s Jupiter’s innermost moon Io and it appears near the right edge of Jupiter in a telescope.

RACHEL
That’s Idaho Skies for the second week of May. Next week the Flower Moon passes between two bright planets.

PAUL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Paul…

RACHEL
…and Rachel.

PAUL
Dark skies and bright stars.

Monday, May 2, 2016

Idaho Skies for May 2016



May 1 – 7

The moon is new on the 6th, but on the mornings of the 2nd and 3rd, it’s visible in the low east before sunrise. If you leave for work before sunrise, be sure to take a look at the moon and Earthshine on its right side. You’ll need to make this observation by around 4:45 AM. Much later and the light of dawn will wash out Earthshine.



The Eta Aquarid meteor shower peaks on the night of the 6th and morning of the 7th, which is awesome since this is a Friday night and Saturday morning. We can observe up to 30 meteors per hour from this shower; unfortunately, this is the case if you live the southern hemisphere. However, it’s still worth observing this shower as the nights are getting warmer and the moon is new. That means we’ll have warm, dark skies for observing this shower. There’s no need to watch this shower all night, as the radiant for the shower doesn’t rise until after 3:00 AM. So look for meteors appearing from the low east after 3:00 AM.  


 May 8 – 14
The moon reappears in the low west-northwest on the 8th. So after it gets dark after 10:00 PM, look for the moon and see if you can detect Earthshine illuminating its dark portion. Earthshine will be most visible if you view the moon through binoculars. The brightish orange star to the left of the moon is Betelgeuse, a star in the shoulder of Orion. You can make observations of Earthshine for several more nights.


Mercury made an evening appearance last month, but disappeared before the end of April. This month Mercury passes between Earth and the sun and in Idaho, we get to see a part of that. This is called a transit and it only happens on an average of 13 times per century. The transit begins on the 9th at around 7:00 AM in Idaho and ends shortly after noon.


A transit is not safe to observe directly with your eyes, since it requires looking at the sun. This means that a telescope properly covered with solar viewing filters can observe the transit of Mercury, but other instruments cannot. The rest of us will need to rely having an acquaintance who is an amateur astronomer, finding a local astronomy club giving public viewings, or using the projection method of observing the sun. How can you project an image of the sun? A pair of binoculars, spotting scope, or small telescope pointed at the sun will project an image of the sun out its eyepiece. Do NOT look at this image through the eyepiece. Instead, position the telescope so that the image projecting out of the eyepiece falls upon a sheet of paper. Then focus the binoculars, spotting scope, or telescope so that the image is sharp. Any sunspots visible during the transit will appear to have fuzzy edges while Mercury will be a tiny round dot with well-defined edges. Mercury will transit south of the sun’s equator, from Earth’s perspective. Remember that if you observe the transit with a telescope, the image will be upside down.   

Gemini appears like the waist and legs of a soccer player. Look in the low west after dark in May and you’ll see upright Gemini as two columns of stars. At the top of the columns are two bright stars, Pollux (on the left) and Castor (on the right). Castor and Pollux mark the head of the Gemini Twins, but more like the waist of a soccer player. Even better, on the evening of the 9th, the crescent moon appears at the feet of Gemini just like Gemini is about to kick it like a soccer ball.


One of the closest stars to the sun appears to the lower left of the moon on the 10th. The star’s name is Procyon, which means “Before the Dog”. The dog in this case is the Dog Star, Sirius. Procyon gets this name because it rises shortly before the rising of Sirius. Procyon is the eighth brightest star in the sky because it’s only 11.5 light years away and not because its particular bright compared to other stars. Procyon is a young star, only one quarter the age of the sun. Procyon is the brighter of the two stars forming the constellation of Canis Minor, or the Little Dog.      


Hey, want to see a really nice star cluster? You can on almost any night, but the 11th is better because the moon will help you find it. The star cluster is named the Beehive Star Cluster and you’ll find it 7 degrees above the moon on the night of the 11th. To see this attractive star cluster, point you binoculars at the moon and then tilt them directly north of the moon. Just after the moon leaves the binoculars’ view, the Beehive will appear at the top of the field of view. You should see a striking similarity between the Beehive and a swarm of bees.


The moon reaches the first quarter phase on the 13th. The star Regulus also appears above the moon that night. Regulus is the brightest star of Leo the Lion. The constellation is standing on end above the moon that night. Regulus is so close to the moon that both can be seen together at the same time through binoculars.


There’s an even brighter star above the moon on the night of the 14th. In his case, the star is Jupiter, the King of the solar system’s planets. Both the moon and Jupiter can be seen together in your binoculars on the 14th. You should notice that Jupiter appears as a more intense source of light than the moon and that it is accompanied by a retinue of satellites. On the 14th, binoculars will let you see up to three of Jupiter’s moons. From left to right, the moons will be Callisto, Europa, Jupiter, and Ganymede. The planet’s innermost moon Io very close to Jupiter and might not be visible through binoculars. If you have a spotting scope or larger, then Io appears near the right edge of Jupiter.

May 15 – 21

The moon passes very close to Spica on the night of the 17th. Spica is the brightest star of Virgo the Maiden, the second largest constellation. Virgo is made up of dim stars, so the constellation doesn’t stand out to the extent its large size should make it. One depiction of Virgo is as a goddess of justice named Justitia. In this guise, she holds the scales of justice in her hands, or the constellation of Libra.   

A widely spaced double star located in Libra can be found below the moon on the 19th. The star’s name is Zubenelgenubi and the angular distance between the companion stars is wide enough that some people can see it as two separate stars without optical aid. The rest of us need a pair of binoculars. The star is 5 degrees below the moon, therefore, place the moon at the top of your binocular’s view and Zubenelgenubi will be the bright pair of stars at the bottom.


The moon is full on the 21st. Full moons in May are sometimes called the Flower Moon and you’ll find the Flower moon located between the planets Mars and Saturn. Mars will be the bright orange-tinted star to the right of the moon and Saturn will be the fainter yellow-white star to the lower left of the moon. Below the moon is another orange star, Antares. Antares is the heart of Scorpius the Scorpion.

May 22 – 30

Mars reaches opposition on the 22nd. At opposition, superior planets, or those beyond Earth, are at their closest to Earth for the year. Opposition occurs when the faster orbital motion of Earth results in Earth catching up to and passing the superior planet in question. In the process of reaching opposition, superior planets appear to retrograde, or move slightly backwards across the stars. Retrograde motion is an illusion caused by the changing perspective between Earth and superior planets when compared to the fixed stars. Hundreds of years ago, when the geocentric or Earth-centered solar system was in vogue, astronomers and philosophers believed the superior planets actually moved backwards during a short period of time. This was possible because these planets orbited Earth in a set of nested orbits of various sizes. Copernicus convinced astronomers in the 16th century that the retrograde motion of the planets was easier to explain by moving the sun to the center of the solar system and demoting Earth to a planet orbiting the sun.   


The bright yellowish star visible to the right of the moon on the 22nd is Saturn. You’ll need at least a spotting scope capable of magnifying at least 25 times in order to see the planet’s rings and largest satellite, Titan. Titan is a fascinating world. It’s larger than Earth’s moon and surrounded by an atmosphere denser than Earth’s. Unfortunately, it’s intensely cold on Titan. So cold that methane, a gas used to heat our homes, is a liquid. Its nitrogen-rich atmosphere is almost cold enough to liquefy. Because of its dense atmosphere and liquid methane, Titan has weather, but probably not as dynamic as Earth’s. This still allows it to rain on Titan, but with methane rain.   

If you’re a late night person, you can use the moon to locate several star clusters and nebulae on the morning of the 24th. These attractive deep sky objects are located between Earth and the center of our galaxy, meaning they appear in the thick of the Milky Way (which is why you need to wait until after midnight to see them). These clusters and nebulae are small, so you need a pair of binoculars to see them. Through binoculars, the nebulae will appear as fuzzy spots while the star clusters will have some stars sprinkled among the fuzz.  
  

The moon is last quarter on the 29th, which is nice, but it has a neighbor that night that will give you a real astronomy challenge. The eighth planet, Neptune is just 4.5 degrees away from the moon on the 29th. This means you can see both together in a pair of binoculars, which typically have a field of view of 5 degrees. You need dark skies in order to see Neptune, so leave town for the countryside. To see Neptune, place the moon on the right edge of your binoculars and find the brightest star directly east of the moon. This star will be near the left edge of your binoculars. A small distance farther east of the bright star is a faint star that’s as bright as Neptune. The distance between the star and the brighter star is the same distance Neptune is away from the bright star. Neptune is the other faint star down and slightly left of the bright star. The bright star, faint star, and Neptune will form a small triangle with a 90 degree apex.    


The moon is close to the eastern horizon as you drive to work on the 31st. Can you see Earthshine? Binoculars will definitely help (but don’t use binoculars while you drive!).



This Month’s Sources

Astronomical Phenomena of the Year 2016, The Nautical Almanac Office and Her Majesty’s Nautical Almanac Office
Astronomy Calendar of Celestial Events for Calendar Year 2016, http://www.seasky.org/astronomy/astronomy-calender-2016.html
Climate of Titan, https://en.wikipedia.org/wiki/Climate_of_Titan
Mercury Transits the Sun, http://skyandtelescope.com/observing/ceelstial-objects-to-watch/mercury-transits-thesun/
Night Sky Explorer
Virgo, https://en.wikipedia.org/wiki/Virgo_(constellation)