It's about one-one-thousand-five-hundredth as heavy as a Polar Bear
In other words, 0.000000000310 megatonnes is 0.000601 times the weight of a Polar Bear, and the weight of a Polar Bear is 1,660 times that amount.(Ursus maritimus) (adult, male)
An adult, male polar bear weighs between 0.0000005160 megatonnes. Polar bears are so heavily insulated by their 9.9 cm (3.9 in) layer of blubber that they are often difficult to detect using infrared photography sensors.
It's about one-one-thousand-five-hundredth as heavy as a Grizzly Bear
In other words, 0.000000000310 megatonnes is 0.000595 times the weight of a Grizzly Bear, and the weight of a Grizzly Bear is 1,680 times that amount.(a.k.a. brown bear, a.k.a. silver bear, Ursus arctos horribilis) (Adult, male, coastal area population average)
An adult, male grizzly bear from a coastal area (where food is plentiful) can weigh up to 0.0000005210 megatonnes. In spite of their tremendous size, grizzly bears can run at speeds of up to 55 kph (34 mph).
It's about 2,000 times as heavy as a Raindrop
In other words, the weight of a Raindrop is 0.0005 times 0.000000000310 megatonnes.(a.k.a. drop, a.k.a. droplet) (average)
The weight of a raindrop depends heavily on the type of weather, but averages about 0.000000000000200 megatonnes. The familiar teardrop shape of a raindrop is actually an optical illusion, caused by the reflection of the light and the motion of the drop.
It's about one-two-thousandth as heavy as a Cow
In other words, 0.000000000310 megatonnes is 0.00046 times the weight of a Cow, and the weight of a Cow is 2,200 times that amount.(for Holstein, a.k.a. Holstein Friesian, a.k.a. Friesian, Bos primigenius) (adult, heifer)
A mature Holstein cow (the well-known black-and-white, spotted breed of cow) typically weighs 0.000000680 megatonnes. President William Howard Taft (1909 - 1913) kept a Holstein cow named Pauline Wayne on the White House grounds — a gift from a Wisconsin senator and the source of the First Family's milk.
It's about one-five-thousand-five-hundredth as heavy as a Car
In other words, 0.000000000310 megatonnes is 0.0001877 times the weight of a Car, and the weight of a Car is 5,328 times that amount.(for 2009 Ford Taurus) (curb weight)
A 2009 Ford Taurus weighs 0.0000016520 megatonnes. The first mass-produced car, the Curved Dash Oldsmobile — introduced in 1901 — weighed just 0.0000003860 megatonnes.
It's about one-six-thousandth as heavy as a Giraffe
In other words, 0.000000000310 megatonnes is 0.000161 times the weight of a Giraffe, and the weight of a Giraffe is 6,210 times that amount.(Giraffa camelopardalis reticulata) (adult, male, maximum of range)
An adult, male giraffe can weigh up to 0.000001930 megatonnes. Reaching 5.5 m (18 ft) in height by adulthood, giraffe calves can grow as much as 3 cm (1 in) per day.
It's about one-six-thousand-five-hundredth as heavy as a Rhinoceros
In other words, the weight of a Rhinoceros is 6,700 times 0.000000000310 megatonnes.(for Black rhinoceros, Diceros bicornis) (Adult, male)
An adult black rhinoceros weighs between 0.00000210 megatonnes. Rhinoceros are extremely aggressive — nearly one of every two males will die as a result of fighting with other rhinoceros.