It's about two times as heavy as The Heart of a Blue Whale
In other words, 0.000000420 megatonnes is 2.10 times the weight of The Heart of a Blue Whale, and the weight of The Heart of a Blue Whale is 0.480 times that amount.(Balaenoptera musculus) (adult)
(for a 2014 specimen)
The heart of a blue whale weighs about 0.000000200 megatonnes. These hearts pump an estimated 7,100 L (1,875 gal) of blood through the whale's massive body.
It's about two-and-a-half times as heavy as a Reindeer
In other words, 0.000000420 megatonnes is 2.540 times the weight of a Reindeer, and the weight of a Reindeer is 0.3940 times that amount.(for Rangifer tarandus granti, adult, bull) (a.k.a. Caribou) ()Rangifer tarandus)
An adult, male reindeer weighs between 0.0000001660 megatonnes. Reindeer undertake a lengthy annual migration, with some herds traveling up to 5,000 km.
To all those observing, Merry Christmas from the Measure of Things.
It's about three times as heavy as a Panda Bear
In other words, 0.000000420 megatonnes is 2.80 times the weight of a Panda Bear, and the weight of a Panda Bear is 0.360 times that amount.(a.k.a. Giant Panda, Ailuropoda melanoleuca)(Adult, male)
An adult, male Giant Panda weighs up to 0.000000150 megatonnes. Despite having the digestive system of a carnivore, the panda eats only bamboo and must eat up to 0.00000000640 megatonnes of it per day to compensate for the limited energy the plant provides.
It's about one-fourth as heavy as a Car
In other words, 0.000000420 megatonnes is 0.25420 times the weight of a Car, and the weight of a Car is 3.9340 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-fifth as heavy as a Giraffe
In other words, 0.000000420 megatonnes is 0.2180 times the weight of a Giraffe, and the weight of a Giraffe is 4.590 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 five times as heavy as a Kangaroo
In other words, 0.000000420 megatonnes is 4.90 times the weight of a Kangaroo, and the weight of a Kangaroo is 0.20 times that amount.(for red kangaroo, Macropus rufus) (adult, male)
An adult, male red kangaroo weighs up to 0.0000000850 megatonnes. Fantastic jumpers, red kangaroos can leap horizontally 9 m (30 ft) and vertically 3 m (9 ft) in a single bound.
It's about one-fifth as heavy as a Rhinoceros
In other words, the weight of a Rhinoceros is 5 times 0.000000420 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.