It's about one-two-hundred-thousandth as heavy as a Polar Bear
In other words, 0.00000000000250 megatonnes is 0.000004840 times the weight of a Polar Bear, and the weight of a Polar Bear is 207,000 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-two-hundred-thousandth as heavy as a Grizzly Bear
In other words, 0.00000000000250 megatonnes is 0.00000480 times the weight of a Grizzly Bear, and the weight of a Grizzly Bear is 208,000 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 one-two-hundred-fifty-thousandth as heavy as a Cow
In other words, the weight of a Cow is 270,000 times 0.00000000000250 megatonnes.(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-six-hundred-fifty-thousandth as heavy as a Car
In other words, 0.00000000000250 megatonnes is 0.0000015130 times the weight of a Car, and the weight of a Car is 660,900 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-seven-hundred-fifty-thousandth as heavy as a Giraffe
In other words, the weight of a Giraffe is 769,000 times 0.00000000000250 megatonnes.(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-eight-hundred-fifty-thousandth as heavy as a Rhinoceros
In other words, the weight of a Rhinoceros is 830,000 times 0.00000000000250 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.
It's about 0.0000010 times as heavy as The Tongue of a Blue Whale
In other words, 0.00000000000250 megatonnes is 0.000000930 times the weight of The Tongue of a Blue Whale, and the weight of The Tongue of a Blue Whale is 1,100,000 times that amount.(Balaenoptera musculus) (adult)
The tongue of a Blue Whale can weigh up to 0.00000270 megatonnes. Despite their tremendous size, blue whales feed almost exclusively on tiny crustaceans called krill and cannot swallow anything much larger than a beach ball.