Our single Bhu-Mandala universe with its 14 planetary systems, is found deep inside and surrounded by a greater universal body called a Brahmanda.

The Bhu-Mandala universe is not to be confused with our ''small earth mandala'' or global planetary sphere we live on. 

The Bhu-Mandala universe is also known as the "greater Earth Mandala" described in Srimad Bhagavatam's 5th Canto as almost being 500,000,000 yojanas (4 billion miles) in diameter, that includes 14 different planetary systems that make up this single material universe. 

The large Earth mandala is not be be confused with our small earth planet global sphere within the Bhurloka planetary system. 

The way to understand the size of the universal Brahmanda material  universe that our smaller universe exists deep inside, it is as follows- 

First, multiply the size of our 4 billion mile diameter universe by 10 to get the diameter of the first layer "earth."

Then multiply 40 billion miles diameter by 10 to get the diameter of water.

Like this all the way through the 7 elements. 

1 -10×4=40 billion miles in diameter (earth)

2 - 10×40=400 billion for (water)

3 - 10×400= 4000 (4 trillion) (fire)

4 - 10×4 (trillion)=40 trillion (air)

5 - 10x40= 400 trillion (sky)

6 - 10x400=4000 trillion (4 quadrillion) (false ego)

7 - 10×4 quadrillion=40 quadrillion (total material energy)

So, our Brahmanda universal shell that houses our smaller almost 500,000,000 yojanas (4 billion miles in diameter) secondary universe, is 44 quadrillion 444 trillion 444 billion miles in diameter, or double that if the figure is measured from one side of the inner outer edge of our secondary universe inside the Brahmanda.

If this description was drawn to proper scale, our inner Bhu-Mandala universe would appear almost invisible at the center of the Brahmanda because of its massive size. 

So in conclusion in this regards, our 4 billion mile diameter small universe is deep inside, and surrounded by a greater universe called a Brahmanda, that is 44 quadrillion 444 trillion 444 billion miles in diameter, or even double that size depending on how the Brahmanda is measured.

Srimad Bhagavatam - "Every universe is covered by seven layers—earth, water, fire, air, sky, the total energy and false ego—each ten times greater than the previous one. There are innumerable universes besides this one, and although they are unlimitedly large, they move about like atoms in You. Therefore You are called unlimited [ananta]." (SB Canto 6 Ch 16 Text 37)

Srila Prabhupada- "This verse describes the coverings of the material universe (saptabhir daśa-guṇottarair aṇḍa-kośaḥ).

1 - The first covering is earth,

2 - The second is water,

3 - The third is fire,

4 - The fourth is air,

5 - The fifth is sky,

6 - The sixth is the total material energy (mahat-tattva ),

7 - The seventh is the false ego.

Beginning with the covering of earth, each covering is ten times greater than the previous one. Thus we can only imagine how great each universe is, and there are many millions of universes." (SB Canto 6 Ch 16 Text 37 Purport)

As said above, our single Bhu-Mandala material universe is deep inside, and surrounded by a greater universal body called a Brahmanda.

Bhu-Mandala is not to be confused with our ''small earth mandala'' or global planetary sphere we live on.

Therefore, there are two Earth Mandala descriptions in Srimad Bhagavatam.

1 - "The large Earth Mandala" called Bhu-Mandala which refers to our entire 6 billion 437 million kilometres in diameter (4 billion mile diameter) material universe with its 14 planetary systems that is almost 20 billion kilometers in circumference. 

Way to big to be our small earth planet.

2 - "The small earth mandala" which is our small round earth global sphere planet in outer space that has a diameter of 12,742 Kilometres and is in the middle planetary system known as Bhurloka as shown in the photo of the 14 planetary systems.

So Bhu-Mandala is the greater Earth Mandala or the 4 billion mile diameter material universe we live in.  

This means the earth globe is NOT Bhu-Mandala because Srimad Bhagavatam describes Bhu-Mandala being almost 4 billion miles in diameter.

Also, certain terminologies in Srimad Bhagavatam gives the false impression our earth planet is flat which is absurd nonsense, the earth planet is a globe.

Srila Prabhupada - "Dvipas (islands) are also planets (globes) in outer space." (CC Madhya 20.218)

Srila Prabhupada - "Just like here, in this planet, when you go up, you see it is a ball." (Lectures on BG 2.12, New York City, March 9, 1966)

The circumference of our earth globe around the equator is 40,075 km and our earth planet's diameter is 12,742 km.

Way too small to be Bhu-Mandala, so NO WAY is our small earth globe Bhu-Mandala which is way to big to be our small earth.

4 billion miles in diameter happens to be the size of our entire single material universe according to Srimad Bhagavatam's 5th Canto  

Each Brahmanda a secondary material universe is also in, is almost spherical shaped.

An unlimited number of these Brahmanda greater universes come from the Bodily pores and breathing of Maha-Visnu, in different sizes.

The size of the Brahmanda and its secondary material universe deep inside it, depends on the number of heads there Lord Brahma has, some have 4 heads, like our Lord Brahma has, others have 10, 20, 50, 100, 500, 5000, even a million, it is inconceivable for our small brains to comprehend.

As said above, the Brahmanda outer covering of our inner material universe is enormous and has 7 material layers of gross and subtle material qualities.

Our Brahmanda is 71 quadrillion, 715 trillion, 715 billion kilometers in diameter (44 quadrillion 444 trillion 444 billion miles in diameter) and having a circumference of almost 242 quadrillion kilometers.<×>