The Voyager space missions are humanity’s most remarkable achievement. The Voyager missions will still be active long after we’re all gone. 

The Farthest: Voyager in Space is about the fundamental questions of science. What is the universe made of? Where did life begin? Are we alone in the universe?

This is one of the best space documentaries ever made, and it’s streaming on Netflix.

Voyager Objectives

The primary mission goal is to collect data from Saturn and Jupiter. Primary mission success means the spacecraft continues to Uranus, Neptune, and interplanetary space. 

Golden Records

The Golden record’s goal is to capture the diversity of life and culture on Earth. Instructions on how to play the record are on the record jacket. The concept is that this record is planet earth saying, “Hello!” Each record contains images, music, sounds, and greetings from various cultures across Earth.

Engineers share their frustration with the Golden Records. The records may be humankind’s introduction to another species. What’s included on the record? How do you select 100 images to represent humanity? What music represents all cultures? Should we include a roadmap to Earth?

Planetary gravitational slingshot 

Once every 176 years, the outer planets in our solar system “line up in a row” for a short period. NASA scientists race to take advantage of this opportunity.

Harnessing planetary gravitational forces allows the spacecraft to adjust its trajectory without fuel. The gravitational forces of Jupiter slingshot the Voyager spacecraft towards Saturn. Then from Saturn to Uranus, and Uranus to Neptune.  

If the Voyager can catch the alignment window, it will travel from Saturn to Neptune in twelve years. Missing the alignment window equates to a thirty-year trip.  

Unexpected discoveries

What’s NASA life like when Voyager approaches a planet?  Data begins to pour in from the spacecraft. Images to analyze, data to interpret, and press conferences galore. 

The film rewards the viewer with ah-ha! moments during planetary flybys. Raw, unprocessed images allow us to see the planets bouncing around the camera’s field of view. Distorted, distended, defocused images transition into crisp, high-resolution images. The images are breathtaking.

We’re in the room when discoveries occur. The planetary images are enough to rewrite science textbooks.

Are we alone in the universe?

When the Voyagers have depleted their power supplies, the Golden Records become the primary mission. The Farthest: Voyager in Space discusses the possibility of extraterrestrial life. We appreciate the intelligent conversation.  

Early in the film, there’s a discussion between NASA and the U.S. President about mission funding. NASA shares why the Voyager mission is essential. The stated goal is Jupiter and Saturn data collection.  

NASA doesn’t mention its own secondary, somewhat secret, goal. A hope that the Voyagers would travel for a much greater distance than “only” Saturn and Jupiter. 

Wrap up

The Farthest: Voyager in Space begins to address the fundamental questions of science. We suspect the real answers from the Voyager missions may be tens of thousands of years away. 

This is one of the top ten space documentaries that we recommend. Click here to check out the rest!

When most people talk about the solar system, they’re thinking of the big guys—large planets like Jupiter and Neptune. 

However, there are also smaller planets, called dwarf planets in the solar system. 

These dwarf planets are much farther away, and have some slightly different characteristics. Let’s go over what they are and why they can’t be considered true planets!

What Are Dwarf Planets?

This concept was integrated into the world of astrology in August 2006, when the International Astronomical Union decided that Pluto was no longer a planet and changed its title. While it was no longer the farthest planet from the sun, it was still part of the solar system as a dwarf planet.

According to the IAU, dwarf planets have to meet both the basic requirements to be a planet:

1. They must orbit a star
2. They must have enough mass to have a spherical (or nearly spherical) shape through hydrostatic equilibrium. 

However, those aren’t the only requirements they have to meet. In addition to those requirements, they also have to meet the following criteria:

• Can’t be a satellite of a planet or another stellar body
• Must share the vicinity of the orbit with other objects

As long as a planet meets those four criteria, you’ve got a dwarf planet on your hands. 

Currently Known Dwarf Planets

The whole dwarf planet thing started one year before Pluto got kicked out of the solar system (not literally, just technically speaking). 

This is when a celestial body called Eris was found. 

Scientists began to debate whether Eris should be added as the tenth planet in the solar system, or whether it deserved its own classification. 

As you can tell, they decided on the latter. However, that also meant that they had to re-examine Pluto’s classification, naming it as a dwarf planet too. 

Once this classification was established, it paved the way for scientists to identify and classify other dwarf planets. Today, there are five known dwarf planets: 

1. Ceres
2. Pluto
3. Haumea
4. Makemake
5. Eris

Let’s take a closer look at each of them. 

Ceres

Ceres is the dwarf planet closest to the sun. It’s a trans-Neptunian object, with a distance of 413,690,250 km from the sun, and was the first visited by NASA’s Dawn space probe. Before being a dwarf planet, until 2006, it was classified as an asteroid.

Pluto

Pluto is a frozen dwarf planet, whose average temperature sits at -240 ºC. This dwarf planet can, at times, can be closer to the sun than Neptune due to its orbit. 

Haumea

Haumea is similar in size to Pluto and is the fourth in the solar system when it comes to dwarf planets. It was discovered in 2003, but it didn’t get classified as a dwarf planet until after Pluto. 

This planet is shaped like a rugby ball, and half a decade ago, it was discovered that it was the first known Kuiper belt object to have rings. In case you’re not clear on where Kuiper is, that’s the same belt that Pluto is located in!

Makemake

Makemake is a plutoid object smaller than Pluto. However, it’s the second brightest plutoid in the Kuiper belt, as seen from Earth. 

Eris

Eris is the fifth and last dwarf planet. That means that it’s the furthest from the sun. It’s also the largest known dwarf planet to date.

Dwarf Planets, a Recent Concept

Astronomers who study space constantly decid to adopt a new terms. That’s how they managed to regroup celestial bodies such as Pluto!

Despite their smaller stature, dwarf planets are still important parts of our solar system. They also are just one more step on the road to many more discoveries about outer space. 

The solar system hasn’t always been what we know of today. As scientists have made new discoveries, they’ve had to make some adjustments including what planets make it up. 

You see, until just over 10 years ago, Pluto was considered the ninth planet and the farthest planet from the sun. 

However, more recently, scientists and astronomers have changed their tune, and today, Pluto isn’t considered a planet at all. Read on and find out what happened to Pluto and what its current characteristics are like.

What’s the Deal With Pluto?

Pluto is located in the Kuiper belt and is smaller than the moon. It’s said to be composed of a blanket of frozen water, as well as methane ice and nitrogen frost. The terrain of the planet consists of rocky mountains, valleys, plains, and a glacier.

As you might have guessed from that description, this planet is pretty cold. The average temperature of this dwarf planet is about -240ºC, cooling more at that time of year when the sun is further away. It even gets red, methane snow!

Despite that, when Pluto’s orbit brings it close to the sun, the ice on its surface can turn to gas. During these times, it can actually be closer to the sun than Neptune. 

Is Pluto a Planet?

While Pluto is no longer considered to be the farthest planet from the sun, it is still a part of the solar system, just as a dwarf planet.Previously, Pluto was the farthest planet from the sun, but in 2006 Pluto was determined to be a dwarf planet and was no longer considered a planet. The solar system went from having 9 to 8 planets, causing a before and after in astronomy.

So, what happened?

One year earlier, scientists discovered the dwarf planet Eris. When they did so, they realized that Pluto actually fit the same classification as Eris. 

As a result, scientists were faced with two choices: 

1. Classify Eris as the 10th planet in the solar system
2. Remove Pluto from the solar system

As you now know, International Astronomical Union (IAU) went with the second option.

The Difference between Planets and Dwarf Planets

The IAU didn’t just randomly decide to eliminate Pluto from the solar system. When they made that decision, they had to come up with a new way of classifying spacial bodies. 

What the IAU said is that planets have to meet two requirements: 

1. Orbit around a star without being a star or moon of a planet
2. Have a mass that’s large enough to reach hydrostatic equilibrium (or, in simpler terms, take a spherical shape)

The problem is that both Pluto and Eris met these requirements, as did many other celestial objects! In order to prevent confusion, a resolution issued on August 24, 2006, added a new characteristic that planets had to meet. 

Under this resolution, the IAU said that in order to be a planet, in addition to meeting the two previous requirements, the bodies must have cleared the vicinity of their orbit of other celestial bodies.

In contrast, dwarf planets could share the vicinity of their orbit with other objects. 

To make things even clearer, the IAU also affirmed that the objects that orbit the sun beyond Neptune are trans-Neptunian objects. These are considered plutoids, or dwarf planets that are farther from the sun than Neptune, the farthest planet from the sun.

The Farthest Dwarf Planet from the Sun

What you might now be curious about is what the farthest dwarf planet is from the sun. 

Let us give you a hint: it’s not Pluto!

Eris is farther away from the sun than Pluto, making it the farthest dwarf planet from the sun. However, beyond Eris is another planetary object called 90377 Sedna.

The jury is still out on whether or not this object could be considered a dwarf planet or not. 

From Planet to Dwarf Planet

Although Pluto was once considered a planet, today, it’s been redefined as a dwarf planet. Now it’s a dwarf planet, the second farthest from the sun.

Although it is no longer the farthest planet from the sun, Pluto is still worth knowing about. It’s just the start of us discovering even more about our solar system and outer space!