Blog #8: Aliens?

One of the most common questions people have when they look at the sky is, “Are there any other life out there?” Many would think yes. Many, many stories, shows, and games have been made about alien species living out there. The math also adds up. While the Drake Equation isn’t exact, using any reasonable numbers would result in millions of potential worlds with life in our Galaxy alone.

But according to one Enrico Fermi, something about this felt off. He made a remark which would soon become known as Fermi’s paradox. “Our Galaxy should be teeming with civilizations, but where are they?” The idea behind this thought was that any civilization with rocket technology and a desire to explore could colonize an entire galaxy in 10 million years.

Where are they?

Even though that is a long time, the age of the milky way is over a billion years making it extremely likely that some Alien species would have colonized it by now if estimates such as the Drake Equation was accurate. Unless there were no other intelligent life within the galaxy. Could we be the first race to start colonizing? Could some other race be in the middle of their 10 million year long conquest? Have we already been conquered and just don’t know it yet? The questions just keep piling up!




BLOG #7-Discovering New Planets

On April 26th 2017, Scientists from NASA discovered a curious exoplanet named OGLE-2016-BLG-1195Lb orbiting a small brown dwarf star 13,000 light years away with a mass only 7.8 percent of that of the Sun. This curious planet has a mass similar to that of earth and orbits its mother star at the same distance as Earth does to the sun. It is also covered entirely in ice.  Due to the low energy of the star, and the distance between it and OGLE it is unlikely that OGLE is able to support life. However while there probably won’t be any life on OGLE, its discovery marks a new step in the advancement of discovering exoplanets via the microlensing technique. Microlensing is used to find objects in the sky by using background light from stars as flashlights. When another star crosses over a target star, the gravity of the front star will bend its light around it and make the light from the target appear brighter. If a planet is orbiting the target star, then it will cause a quick blink in the star’s brightness. Microlensing is typically used to find faraway planets, the larger the mass the better, and OGLE has the smallest mass of all exoplanets found so far marking a new step forward for the technique.




Feel Free to OGLE

Blog #6: New Life?

In February 2017, NASA released what could potentially be the most important astronomical discovery ever made. Using the  Transiting Planets and Planetesimals Small Telescope or Trappist for short, NASA discovered a small red dwarf star 39 light years away with three planets positioned similarly to Earth and sun in a fashion that was conducive to supporting liquid water and water based life.

A New World

This phenomenon is called the Goldilocks zone. Named TRAPPIST-1 after the telescope that discovered it, the star itself is barely the size of Jupiter and the seven planets orbiting it do so at similar distances to Jupiter’s moons. However the planets themselves are quite close to each other, being so close that it is speculated that standing on one of them would allow one to see features of neighboring planets in the sky. Should any life exist on any of these planets or not, one thing is certain. They are sure to have an amazing view of the sky, and who knows maybe the life forms living on these planets might even be able to see or communicate with each other as they develop. The possibilities and excitement surrounding the announcement are endless.

Comparison to Jupiter


Blog #5: Pluto’s Demotion

As of August 24th  2006, the international astronomical union voted to demote Pluto to a dwarf planet, ending the nine planet era, redefining the definition of a planet, and rendering many, many astronomy books obsolete. But why was Pluto demoted? What happened to make astronomers cut away a part of so many people’s worldview? Will the International Flora Union demote the Potato from being a vegetable? While I can’t answer that one, we can take a look at why astronomers deem Pluto to be unfit to be a full-fledged planet like the others. In order to be a planet, it has to meet three criteria:

1.It is in orbit around the Sun.

2.It has sufficient mass to assume hydrostatic equilibrium (a nearly round shape).

3.It has “cleared the neighborhood” around its orbit.

Pluto fits the first two criteria by being round and orbiting the sun, but recent developments has caused the third criteria to come into question. In order to qualify, it must be the largest object in the area and have no large objects around it compared to the planet. When Pluto and Charon were first discovered in the 1930s, the technology didn’t exist to detect many of the objects in the Kuiper belt and with more modern telescopes scientists were able to identify more and more bodies in the neighborhood which renders the 3rd criteria false and thusly demotes Pluto as a full planet.

Poor Pluto


Blog #4: The Atmosphere of Venus

Out of all of planets, the one with the highest surface temperature is Venus clocking in at an average of 864 degrees F1. Despite being millions of miles further from the sun than Mercury, Venus still handily beats out Mercury who “only” averages 800 degrees. You probably already know why this is so, but this blog will take a deeper look at the noxious wonder that keeps Venus so warm and gives it its color, its atmosphere. Venus’ atmosphere is made up entirely of carbon dioxide with smaller concentrations of nitrogen and other trace gases such as argon and water vapor. This atmosphere was created when the rocky core of Venus captured surrounding carbon dioxide gas during its formation and is responsible for both the increased temperatures of Venus through the greenhouse effect as well as the increased surface pressure with air weighing 90 times as much on the surface of Venus or the equivalent of diving 3000 feet under the ocean2. Because the atmosphere is so thick with carbon dioxide and is so efficient at trapping heat, nearly all of the hydrogen and oxygen evaporated away leaving Venus a sweltering, toxic wasteland and an example of the worse possible outcomes of uncontrolled Global warming.


The Planet Venus




Blog #3

When we think of waves, the first thing that comes to mind would be waves in the ocean, or perhaps doing the wave at a football game. However there are also a great deal of other waves that are just as important in our lives if not moreso especially in the field of astronomy and these are the waves that make up the electromagnetic spectrum. The EM spectrum consists of radio waves which are the same waves that enable your radio to work and shows the location of stars in space, Microwaves which heat up food, Infrared used by nightvision goggles and maps the dust between stars, visible light which enables us to detect light and to see, Ultraviolet used in tanning and detecting heat in space, X-rays for viewing bones and finding hot gases in the universe, and Gamma rays to see inside the body. Fun fact, the universe is one giant gamma ray generator. The electromagnetic spectrum comprises of a plethora of different waves that have uses both in normal life and in astronomy.

Source: NASA

Waves grouped by wavelength

Blog #2

When you head outside at night to watch the stars and contemplate your own insignificance in the universe, you are partaking in a ritual that has spanned the length of all human existence. By watching the stars and planets in the sky, our ancestors were able to derive a great many advancements that we currently take for granted such as calendars and clocks. There is also a field of science dedicated to learning about these achievements known as Archaeoastronomy. Defined by as “understanding how skywatchers of the past fashioned and refined systems for regulating their primitive calendars and for memorializing celestial events, both cyclical and unique.” By learning how people in the past viewed the stars and grew from them, we can have a greater understanding of how our current world came to be and potentially even use that knowledge to make groundbreaking discoveries of our own.



A glorious tribute to Archaeoastronomy

Blog #1:Solar Eclipses

For many, August 21st  will be the highlight of their year, with many having planned out their day months if not years in advance, finding out prime locations, taking time off, and/or even going out of town. In fact one small town in Kentucky has had all of its hotels booked full for this day in advance for years now. What event is this you might ask? It’s going to be a total solar eclipse. Yes, the totally awesome kind you see on TVs and in movies where the sun becomes entirely covered up and day becomes night. Excited? Well here’s some tidbits about this phenomenon that explains the science behind it all.

Eclipse Diagram

As you probably already know, a Solar Eclipse happens when the moon obscures the sun in its orbit. It can either partially cover the sun, or completely cover the sun. In a total solar eclipse, there are five distinct phases. First is the partial eclipse, where the moon starts moving in over the sun, the second phase is where the  total eclipse begins where the entire sun becomes covered, next comes Totality, AKA the cool part where the sun is completely covered, revealing the Corona and turning the sky dark, then the moon moves away to uncover part of the moon, reverting to a partial eclipse, and finally that ends as the moon completely moves away. And then we won’t be seeing another one here in North America until 2024.

There are also some very interesting sights at Totality that can’t be seen anywhere else. They are Baily’s beads, which are some splotches of light on the edge of the moon, the Corona, the Diamond ring which is the combination of Baily’s Beads overlapping with the Corona, and the sun’s chromosphere, where its red glow can be briefly seen right after the diamond ring disappears. So if you can, make sure to check out this once in a decade phenomenon and don’t forget to bring eye protection!

Special events you can only see during totality.


Introduction to My Blog

Hello everybody, I am Guangze Zheng, Vanderbilt class of 2017 and you are reading my first blog for ASTRO2110, the Solar System as well as my first ever blog on wordpress. This site is completely new to me, so please bear with me if I am ignorant of any features or utilities not specifically outlined in the rubric. Now onto the fun part.

I’ve been interested in space and astronomy for a very long time. When I first immigrated to the United States from China in 2002, I barely knew any English and it was hard to communicate in this new country. This all started to change when I was taken to the local public library and found some books with very interesting pictures on the cover which I would later learn consisted of various celestial bodies such as stars, planets, and galaxies. It piqued my interest enough to really start trying to learn the language so I could understand more than just the pictures, which eventually led into another one of my lifelong hobbies: reading. But that’s another topic.

One of my fondest memories as a child was receiving my first telescope as a birthday gift. It came with a stand and three different eyepieces and had a picture of the moon on the back, showing off its magnifying properties. I spent many nights with friends and family out in the backyard trying to see the moon, the planets, other stars, and possibly even some of the stranger phenomena I only ever read about in the books such as Quasars and Pulsars. I never saw anything other than the moon and a couple of the planets with it, and overall the telescope was never that great, but as a young wannabe astronomer, I had a blast.

My telescope (picture taken by me)

As I grew older, astronomy eventually took a back seat to more immediately pressing matters such as schoolwork, extracurricular activities, etc. I no longer spent hours reading books on the subject I could barely understand and most likely forgot most of the stuff I did read over the years, but I still did see movies such as Interstellar and The Martian along with paying attention to some of the more interesting headlines in the news every now and then for articles such as NASA Wants to Drop a Submarine in Titan’s Ocean to Find Life. Who knows, instead of looking out millions of light years away at distant stars and galaxies, life might exist in our own cosmic backyard. Fast forward to Vanderbilt, and I can nowtake a plethora of different courses on a plethora of different subjects. It’s high time I took some time to re explore one of my older passions and I look forward to learning about the Solar system with everyone in this class.

Thanks for reading, and have a great semester!