Venus

Watching the sky just after sunset you may be noticing the brightest star that appears over the western horizon. This “star” is actually a planet (or wandering star) Venus.

Venus is the third brightest naturally occurring object in our sky (after the Sun and Moon) due to having a thick atmosphere with clouds that reflect sunlight really well. Venus is the closest planet to the Earth and about the same size as Earth both of which also attribute to its brightness.

The key to understanding Venus’s movement in our sky is to remember it’s an interior planet which means it travels around closer to the Sun in an orbit interior to ours. It takes Venus a little over 7 months to travel around the Sun where it takes Earth 12 months. This means every year Venus will pass us on the inside lane at least once. Right now Venus is catching up and will pass us on the inside lane on October 26th. This is called ‘inferior solar conjunction’ and means the Sun, Venus, and Earth will be in alignment. We won’t be able to see it pass us as it will be too close to the Sun to observe. Here in the Front Range, we will stop being able to see Venus in our evening sky in early October due to the mountains covering anything low on the western horizon.

We can’t watch Venus pass us, but right now we can watch it move in for the pass. If you watch the sunset every week or so until October you will see Venus getting closer and closer to the horizon. A few days after inferior solar conjunction (October 26th) we will start seeing Venus on the other side of the Sun in our sky just before sunrise. Watching the Sun rise starting in November you will see Venus climb higher and higher in the morning sky. Venus never travels further than 47 degrees from the Sun. Because of this we only notice Venus at sunset or sunrise when the Sun is blocked by the horizon letting Venus shine in the sky. One small exception to this is during a solar eclipse when the Sun is blocked by the Moon. Some may have noticed Venus next to the Sun during last year’s solar eclipse.

Looking at Venus with a decent pair of binoculars you will see that it currently appears as a crescent. This is because just like the Moon, Venus has phases. Because Venus is currently coming toward us, we can see a portion of Venus that is illuminated by the Sun and a portion that is in darkness (night) facing away from the Sun. The illuminated portion will continue to shrink until Venus is in inferior solar conjunction when we won’t see Venus just like we don’t see the Moon at New Moon. Then in November as we watch Venus rise before the Sun we will also, if we check in weekly with binoculars, see the illuminated crescent grow larger.

Phases of Venus - As we watch the crescent of Venus get smaller "wane" we notice Venus get larger as seen in this picture. This is because Venus is coming closer to us. Venus seen from earth is actually brighter as a crescent then when it is full because of this.

Introduction to the series:

We currently have the best of planets in our night sky for astronomy! For the next couple weeks, I want to take a detailed look at each one with you.

Let’s start by finding and identifying them. Watching the sky after sunset you may be noticing the brightest star that appears over the western horizon during twilight. This “star” is actually the planet Venus! The word planet actually means wandering star because the planets appear to move amongst the stars. Venus is quickly disappearing so much so it's hard to see right now because it is really close to the sun. With the mountains on our western horizon it makes it extra difficult.

Now, drawing an imaginary line south east in the sky from Venus you should run in to another bright ‘star’. This is not as bright as Venus but usually the second point of light that comes out during twilight. This is another planet, Jupiter. Jupiter is currently near a fairly faint star with a really fun name- Zubenelgenubi (I say it zoo-bin-L-gha-new-bee, but you may say anything fun you want). This star represents the southern end of the balance beam of Libra. Now as the reader of a paper you might be familiar with the constellation Libra from the horoscope section and that’s no coincidence. If we look back at Venus we see it too is near a bright star Spica. Spica is the brightest star in Virgo, another constellation you might find a horoscope for. Spica is currently appears closer to the sun than Venus so it will be extra hard to see.

Let's take this line we drew connecting Venus and Jupiter and continue it on. You should also see an obvious red dot of light appearing in the south east, this is Mars. Let’s arch this line a little and put Mars on the line too. Almost halfway between Mars and Jupiter (a little closer to Mars than Jupiter) on this line you might see another brighter light, this is Saturn. If you have dark skies and some imagination you might see a constellation that resembles a teapot below Saturn. This “teapot” was originally seen as an archer, and named Sagittarius. Next to Mars you’re going to need a lot of imagination (or beer) for this but you might make out a horned goat, Capricorn. If you’re following along with the horoscope section you may of noticed I missed Scorpio which currently has no planets but has a truly red star Antares (which means Mars’s rival) that is about halfway between Saturn and Jupiter on this line.

This line connecting all the planets is a very special line we call the ecliptic. The ecliptic simply is the plane of our solar system therefore this line is the only place you will find planets. You can complete the ecliptic, as it circles around the Earth, if you keep drawing the line below your feet and circle the line back to Venus. The Sun and Moon are also on this line! This line is so important, every constellation it passes through is in the zodiac. That’s what the zodiac is for, to denote the plane of the solar system in the sky (not just to fill up the paper). The constellations of the zodiac are therefore the only constellations that are ever visited by planets.

Let’s go back to Jupiter next to Zubenelgenubi. Zubenelgenubi is the part of the balance beam of Libra. So, we can say Jupiter is in Libra. All of the planets, the Sun, and the Moon can be said to be in a certain constellation of the zodiac.

For the next month we will look in detail at each one of these planets along the ecliptic moving west to east in the sky. Check back here next week to learn more about Venus.

New Name:Elevated Astronomy Tours!

We have a new name! Mile High Astronomy Tours is now Elevated Astronomy Tours!

The real news is I got approval from the city of Boulder OSMP to conduct tours on their land!

There's a few reasons for the name change. Elevated Astronomy is more unique. I wanted to honour Boulder (which is more than a mile high 5328ft = 1.009mi... not that it matters) as they are allowing me to do tours with little restriction. Denver mandates all events end prior to sun set (not gonna work for astronomy) due to curfew.

Also I don't like when things are called 'mile high' outside of Denver. Here's the story I wanted to get a Harley shirt for my mate, from my home town, to add to his collection so, I stop in to "mile high harley davidson" to find out I'm in Aurora CO and not one of their shirts says Denver CO just Aurora.

The Denver Museum of Nature and Science changed their name twice now giving them three names The Colorado Museum of Natural History, The Denver Museum of Natural History, and The Denver Museum of Nature and Science. The first time was because they were getting more support from Denver. However, they never really gave up any of their former names you can still say The Colorado or Denver Museum of Natural History as a valid name, they just no longer publicise those names. I like this and am going to approach my name change the same way.

Mile High Astronomy Tours is still a valid name, feel free to call my business whatever you like best!