Sentences - "earth-shattering" and "get off the ground"

"Earth-shattering - something that has a profound (great) impact. 

The death of my grandfather was an earth-shattering news - Good example though it sounds a bit awkward. I would just say "The death of my grandfather was earth-shattering." or "When I received the earth-shattering news that my grandfather had died....."

It is difficult to explain but using the word "news" in your sentence seems to move the focus away from your grandfather's death and put it on the news itself. This implies that the news is actually more earth-shattering than the death of your grandfather.

Some other examples: 

What an earth-shattering election result.

He looked so serious I thought he had something earth-shattering to say.

My team won with an earth-shattering goal!

She is sad because she received some earth-shattering news.

"Off the ground" to get started - normally used in a business context, your example is perfect. 

I think my career will get off the ground in the next year.  

Some other examples:

I need £2500 to get my business off the ground.

We need a marketing company to get our product off the ground.

I'll only get my blog off the ground if I advertise it.

Hope this helps!

You'd say "was an earth-shattering news"

Your "getting off the ground" example is great. Others would involve things like a startup business getting off the ground (you would not use it to describe something small-scale like a meeting starting up, though). If you used it to describe an airline startup "getting off the ground" then I think that'd be interpreted as a gentle joke. If you described your taxi-cab startup "getting off the ground" then that would (to some) sound humorous, too, so hopefully the humor would be intended. :)