I bought EchoStar (ECHO) in my Million Mission portfolio last week.

I believe the stock could double.

But I'll admit, EchoStar isn't the easiest company to understand.

Fortunately, you don't need to understand every nuance to understand why I bought the stock.

My investment thesis comes down to three questions:

• What does EchoStar own?

• What does EchoStar owe?

• What's left for shareholders?

That's it.

And when I run the numbers, I get a value that's roughly twice what Wall Street is currently valuing the company.

Let me show you the math.

Let’s Start With What EchoStar Owns

The biggest asset is one you should be very familiar with: SpaceX.

EchoStar owns 262 million shares of SpaceX after selling wireless spectrum to the company.

At current SpaceX prices, those shares are worth right around $40 billion.

Note: The current market cap of ECHO is only $25 billion.

In other words, the SpaceX stake alone was worth considerably more than the entire company.

And there’s more…

EchoStar also sold spectrum to AT&T and SpaceX for tens of billions of dollars in cash.

Between those transactions, the company has roughly $32 billion in cash.

Plus EchoStar still owns additional spectrum that hasn't been sold.

Spectrum is the wireless frequencies companies use to transmit data. Think cellular networks, satellite communications and other wireless services.

Because there's only so much desirable spectrum available, these licenses can be extremely valuable.

Estimates for EchoStar's remaining spectrum range from $5-10 billion.

Now add everything together:

• SpaceX stake: $40 billion

• Cash: $32 billion

• Remaining spectrum: $5–10 billion

Total Assets: $77–82 billion

This is the first half of the equation.

Now let’s subtract the bills.

Here’s What EchoStar Owes

EchoStar has debt of approximately $18 billion.

Then we have an unknown liability amount.

After selling much of its spectrum, EchoStar no longer needs all the cell-tower infrastructure it previously agreed to use.

Of course, the tower companies aren't simply letting EchoStar walk away.

There could ultimately be another $5–10 billion in liabilities associated with those agreements.

So let's subtract both:

Total Assets: $77–82 billion

Minus: $18 billion in debt

Minus: $5-10 billion in liabilities

That leaves somewhere around $49–59 billion for shareholders.

Now compare that with what I paid.

EchoStar's market cap is currently right around $25 billion – meaning EchoStar has the potential to double from here.

Why I Bought at $86

Notice how I didn’t even mention EchoStar’s ongoing business.

EchoStar still owns Dish, Boost Mobile, and Hughes, which generate billions of dollars in annual revenue.

I didn’t even need to assign value to them.

I'm not buying EchoStar because I expect Dish Network to suddenly start growing again or Boost Mobile to take over the wireless industry.

I'm buying EchoStar for the assets it already owns.

Even after subtracting the company’s debt and potential liabilities, I estimate those assets leave $49–59 billion in value for shareholders.

Compare that with the $25 billion valuation today, and there’s a lot of room for my estimates to be wrong and still make money.

Plus, I get one more thing I’m very happy to own along the way:

262 million shares of SpaceX.

If SpaceX continues climbing, so does the value sitting inside EchoStar.

That’s a setup I’m willing to bet on.