Elliptical vs Spiral Galaxy [How Do They Differ?]

If you were to look through a telescope deep into outer space, you’d be able to see a wide range of galaxies that all seem to carry unique characteristics. Scientists categorize each galaxy based on numerous factors, and many amazing events led to the creation of the different known types of galaxies. Now, you may have heard of Elliptical and Spiral Galaxies. Today, we are going to be exploring exactly how they differ.

So, what are the core differences between an elliptical and a spiral galaxy? Spiral galaxies have a rotating disk of gases, stars, and other celestial objects, whereas Elliptical galaxies don’t have these characteristics. Instead, they are stationary nor show any evidence of star formation.

Of course, it tends to be a bit more complicated than that.

So let’s delve deeper to help clear it all up for you.

What Is An Elliptical Galaxy?

Elliptical galaxies don’t have a visible internal structure, instead featuring an elliptical or oval-like shape, and they are known to have a dense nucleus. These types of galaxies also come with a few subclasses, which are classified as E0 to E7, and this pertains to their overall shape. Elliptical galaxies are also known to be some of the largest and contain older stars which can sometimes cause their common blue color.

Scientists predict that around 20% of the galaxies in our universe are of the elliptical variety, and they don’t have gas or dust clouds as many other galaxies do. 

The stars within an elliptical galaxy are a mix of Population 1 and Population 2 stars.

Although each elliptical galaxy may vary in size or color, what they’re made of is usually the same.

You can find many elliptical galaxies in clusters and a majority of their stars are low-mass due to the lack of dust clouds and gases. It’s known that these types of galaxies can contain around a hundred million up to a hundred trillion stars.

In our modern era, many scientists believe that elliptical galaxies have a black hole at the center that’s related to their overall gravitational force.

They also vastly range in size as some can be at least two lightyears across, while others may only compare to about 10% of the size of The Milky Way.

When looking through a telescope, elliptical galaxies can sometimes be rather hard to find as they don’t tend to be as bright as other galaxies.

Their size also plays a factor in this, and in some cases, they may not be visible at all if they aren’t large enough. This is due to their low-mass stars, which aren’t as bright as many others.

Although elliptical galaxies are known for their size and abundance throughout the universe, there’s plenty of competition.

Spiral galaxies are also quite abundant and come with many of their own qualities that make them stand out among the vast amount of celestial objects around them.

What Is A Spiral Galaxy?

Spiral galaxies are known for their disk-like shape and centrifugal, rotational force. Other unique characteristics include spiral arms, which is where a lot of their star formation takes place. They also boast many different types of dust clouds and gases and are known to be the most common type of galaxy throughout our universe.

Their spiral shape comes from their unique gravitational force, which creates a centrifugal action to occur, affecting every celestial object within it.

For example, The Milky Way is a spiral galaxy, which is why Earth has the rotation that we’re so fond of. Spiral galaxies have three primary features that make them easily identifiable through a telescope.

These include spiral arms, which are directly correlated to their pattern, a central bulge containing old stars, and a bar that goes through the galaxy’s central area.

From rapid star formation to a range of gases and dust clouds, the arms of spiral galaxies are a driving force in how they operate. These galaxies also have the ability to pull objects inward due to their spinning gravitational force.

Around 75% of all galaxies in the universe are thought to be of the spiral variety, and they were the first type of galaxy to be observed in human history.

Interestingly, their spiral arms are created from density waves passing through the disk of the galaxy.

Due to the brighter and younger stars that exist within these types of galaxies, they’re much easier to identify through a telescope.

Spiral galaxies contain around 100 to 400 billion stars and spin around a supermassive black hole, such as Sagittarius A, which has a mass equivalent to four million suns.

Around two-thirds of all spiral galaxies feature a bar-shaped line of stars that lay across the bulging cluster.

Although many scientists refer to spiral galaxies as being the most numerous in our universe, it’s possible that, in reality, elliptical galaxies may outnumber them; we just aren’t able to see them all with the technology we have.

What Is The Difference Between Spiral And Elliptical Galaxies?

There are a number of identifiable differences between spiral and elliptical galaxies. One main feature is the fact that spiral galaxies are rotating disks of gases, dust clouds, and stars. In contrast, elliptical galaxies are stationary and don’t contain such elements or show evidence of star formation.

Other features that separate the two include their structure, as spiral galaxies are relatively flat, and ellipticals don’t have a single shape, as they’re just a large group of stars.

This leads to many different shapes being possible with elliptical galaxies. Spiral galaxies also have a unique centrifugal rotation, and ellipticals have a larger center compared to a spiral galaxy’s more spread-out design.

Spiral galaxies feature their unique arms, which act as a driving force of how they operate, and elliptical galaxies contain many more stars.

There are a range of differences between the two, even if many of them are hard to discern without further investigation. Elliptical galaxies don’t have a dense nucleus like spiral galaxies display, either.

It’s known that spiral galaxies feature a fairly consistent shape, but ellipticals tend to be somewhat random, even if many of them feature similarities.

There’s no clearly invisible structure, and their shape can change significantly over the course of millions and billions of years.

Are There Any Any Similarities Between An Elliptical And Spiral Galaxy?

These two types of galaxies may be quite different in many ways, but they also boast a number of similarities. Both have their own gravitational forces and their own galactic motion, and spiral galaxies come with a lot more force. It’s theorized that both galaxies host a supermassive black hole at the center, and both feature a unique halo structure consisting of stars and other celestial objects and elements.

Aside from the characteristics that make them unique to their categories, both galaxies contain many of the same features; they just operate a little differently.

There are other types of galaxies throughout the universe, but ellipticals and spirals are known to be the most common.

Each type contains many of the same types of celestial objects, but these come with minor differences, such as the types of stars and elements they hold.

Even if these galaxies carry a few similarities, they’re few and far between. For the most part, both galaxies are very different in many ways.

One could argue that life as we understand it would be completely different within an elliptical galaxy.

However, both contain many of the same elements that make life possible.

Many aspects of spiral and elliptical galaxies vary quite a bit, which is what makes them so different, but regardless of these differences, they’ll always feature numerous similarities.

Which Is Bigger A Spiral OR Elliptical Galaxy?

Elliptical galaxies are known to be larger than Spiral galaxies. This is mainly due to their irregular shape and the fact that they contain many more stars. Regarding their size, they’re categorized as either giant or dwarf elliptical galaxies. 

Dwarf galaxies have the possibility of being smaller than spiral galaxies, but when it comes to a numbers game, elliptical galaxies are generally much larger in shape and size.

Some of this information is more complex than just black and white, as galaxies, in general, come with a substantial variety of features, even within their own categories. Ellipticals may be considered the largest, but they still vary in size quite a bit.

To discern this information, scientists had to factor in many different physical aspects of both galaxies.

It isn’t always as easy as looking through a telescope to figure this out, but experts have collected plenty of data that lead them to this conclusion.

Nevertheless, both galaxies are awe-inspiring in size and have plenty of beauty and wonder to bring to the table.

Regardless of their size, many people believe spiral galaxies provide more of a “show” due to their bright nature, but elliptical galaxies are conglomerates of color on their own.

They also lead many scientists to an endless number of questions as to how they work on the inside, as we live within a spiral galaxy ourselves.

There will always be a mysterious quality to the size, shape, and nature of elliptical galaxies.

Other guides you may want to give a read:

• Are Galaxies Flat? [All You Need To Know]