Scientists, using a new 3-D scanning technique, have finally been able to make a reasonable estimate of the weight of the world's most famous Stegosaurus, Sophie.

Determining how much some of the giants that roamed the Earth in the past can be a difficult feat.  After all, its not like you can simply walk up to a dinosaur and ask it how much it weighs.  Instead paleontologists make estimates based on the size of its bones in their thighs and upper arms.

Sophie, stored at the Natural History Museum of London, is the most complete stegosaurus stenops; and now, scientists were able to use 3-D scanning to make a more accurate estimate of her weight. 

Before she was placed on display in 2014, researchers scanned every single bone present in her skeleton, which is 80% complete for a total of 360 bones in all.  Once each bone was digitized, the bones were measured by volume, which could then be translated into mass, using comparisons of living creatures.

So how much did Sophie weigh when she was alive and well and roaming the Earth?  The estimate is 3,527 pounds, the same as the number calculated by the traditional thigh and upper-arm method.  Because Sophie was so complete, she offered researchers a rare opportunity to cross check two methods of weight estimation using the same skeleton, resulting in both methods now being considered more accurate.

The findings highlight how fickle weight estimations of dinosaurs can be, however.  Originally, the traditional method produced an estimate nearly twice what the new method found.  Researchers then determined that Sophie had still been growing when she died meaning her body hadn't caught up with her adolescent limbs.  Knowing this they adjusted their calculations and arrived at the same number as the new 3-D scanning technique.

So why bother spending so much time trying to determine the weight of a dinosaur?  Scientists need an accurate estimate of weight in order to determine exactly how the animal lived.

"If we want to estimate how fast an animal runs, you need body mass; if you want to say something about their metabolism, you need to know their body mass," lead author and Natural History Museum paleontologist Charlotte Brassey said.

So what comes next for Brassey and Sophie?  One of the next projects planned is to use the digital scans of Sophie's skeleton to add muscles in the hopes of determining how Sophie walked and to create digital simulations demonstrating her walk to the world.