Neil deGrasse Tyson Is Wrong: Thor’s Mjölnir & Metallic Hydrogen

“Whosoever holds this hammer, if he be worthy, shall possess the power of Thor.” – King Odin Borson of Asgard


Mjölnir (Norse: “that which smashes”) is the mystical hammer of Thor the Norse God of Thunder and Lightning[0]. Depicted as one of the most fearsome weapons, capable of levelling mountains; it is comparable to King Arthur’s Excalibur and the Christian Crucifix in terms of its cultural significance, more so with the cinematic success of Marvel Comics adaptation of the hammer and its wielder.

Resulting in many variations of this mythological weapon (however for this article the focus will be on the Primary Continuity’s version):

Primary Continuity (Earth-616)
Marvel Cinematic Universe (Earth-199999)
Ultimate Universe (Earth-1610)

Thus it is not surprising to see much debate and discussion of this now item of popular culture, and herein we come across its most (in)famous misconception.

The American astrophysicist, Neil deGrasse Tyson, who currently serves as the Director of the Hayden Planetarium at the Frederick Phineas and Sandra Priest Rose Centre for Earth and Space in New York City; tweeted that:


Now this tweet presumably delighted many a reader on the alleged weight of Mjölnir, the mystical hammer than cannot be lifted by those who are unworthy. However, Dr. Tyson is wrong on account of both the material and origin of the hammer and resultantly its weight.

Now, for starters Mjölnir is not “made of neutron-star matter” rather it is constructed from the fictional metal ore called Uru, that resembles stone but it also seems to have metallic properties and a lustre has been described as “badly wrought iron”.

Now Uru is a highly un-malleable metal, often requiring extreme methods to forge it such as the enchanted forge of the the Dwarven brothers Sindri [or: Eitri] and Brokkr, or in the case Mjölnir – the core of a star as the mould (exploding the star in the process).

Dr. Tyson has the made the common mistake of believing that Mjölnir was forged of the core of a dying star, wherein fact it was forged in the core.

Now we come to the matter of Mjölnir’s weight, Dr. Tyson gives us the weight of “a herd of 3000-billion elephants”, this is a fair calculation for him to make, as neutron stars are the densest and smallest stars known to exist in the universe; with a radius of only about 12–13 km (7 mi), they can have a mass of about twice that of the Sun.

However according to Marvel Comics, Mjölnir wears nowhere near that, as a 1991 issued trading card of “Thor’s Hammer” outright states that its composition is of “Asgardian Uru metal” with a weight of only 42.3 lbs.

Its a weapon that must be “terribly well-balanced”, as to be otherwise, such as “if there’s too much weight, you [would] lose power on the swing.”[1]


The misconceptions of the its weight come not just from misunderstanding of its composition but also a misunderstanding of the Worthiness Enchantment placed upon it by the Asgardian All-Father and King Odin – which of prevents it from being wielded by anyone save those who have been found worthy.



Which has included from the mainstream Earth-616 reality –

  • Thor Odinson
  • Red Norvell (AKA: Roger Norvell)[2]
  • Buri[3]
  • Bor Burison[4]
  • Donald Blake[5]
  • Thunderstrike (AKA: Eric Masterson)[6]
  • Storm (AKA: Ororo Munroe)[7]
  • Wonder Man (AKA: Simon Williams)[8]
  • Jake Olson (Duplicate)[9]
  • Servitor the 23rd Century Mining Robot of Tomorrow Man (Ar. Artur Zarrko)[10] [11]
  • Throg the Frog of Thunder (AKA: Simon Walterson)[12] [13]
  • Awesome Andy (Awesome Android)[14]
  • Air-Walker (Herald of Galactus Automaton)[15]
  • Loki Laufeyson (Ikol Incarnation)[16] [17] [18]
  • Jane Foster[19] [20]
  • Odin Borson[21]
  • Beta Ray Bill[22]
  • Captain America (AKA: Steven Rogers)[23]

This is of course irrelevant of its weight; as it should be noted the Kryptonian superhero Superman (Kal-El / Clark Kent), was only able to lift the hammer once through the permission of Odin[24], despite his strength making him capable of lifting far in excess of one billion tons (having once moved the Earth away from the Sun with the aid of Green Lantern (Hal Jordan) while Starbreaker (Luciphage) was pushing it toward the Sun – a feat that at minimum would require quintillions of tons of force)[25] [26], showing the lack of correlation between the enchantment and weight of the hammer.


One interesting discussion about Mjölnir comes from Professor Suveen Mathaudhu, an Assistant Professor in the Mechanical Engineering Department and Materials Science and Engineering Program of University of California (Riverside)[27], and who is viewed as an expert on the science of superheroes as depicted in comic books and their associated movies, frequently speaking and consulting on the subject.

Suveen Mathaudhu - Thor's Hammer

Beyond acknowledging Dr. Tyson’s “critical mistake … [of] … thinking that Mjolnir was forged of the core of a dying star, when it was actually forged in the core of a dying star…”[28], and for highlighting the official weight of the hammer via the 1991 Trading Card, Prof. Mathaudhu presents an interesting theory.

From the dimensions and weight stated on the 1991 Trading Card, he estimates that the density of Mjölnir is about 2.13 grams (g) per cubic centimeter (cc). Lighter than aluminium, which only has a density of 2.71 g/cc.

Thus Prof. Mathaudhu proposes that “Perhaps Uru is the ‘holy grail’ of high-pressure physics: a form of metallic hydrogen …”, and that “Some predictions of the density of metallic hydrogen fall into this range, it requires extreme conditions to form, and could be a tremendous energy source. It’s thought to be present at the core of planets, such as Jupiter, and at the core of suns – which are stars, after all.”

So there you have it, Dr. Tyson’s popular tweet is incorrect, due to misunderstanding, but it has resulted in a rather fascinating theory on the actual scientific understanding on a object thats “mystical nature makes further analysis impossible”. Perhaps the third of Arthur C. Clarke’s Three Laws is correct, and that Any sufficiently advanced technology is indistinguishable from magic”[29].



It should be noted that many individuals have lifted Mjölnir throughout comic book history, be it in the mainstream universe (Earth-616) or a variety of alternative realities, however this have been overlook due to the origin in loophole abuse and/or for happing in a reality not of the primary continuity.

These include, but are not limited:

The Mutant Magneto (AKA: Max Eisenhardt), who in the Ultimate Universe (Earth-1610) was able to use his mastery of electromagnetism to manipulated the environment around Mjolnir rather than truly lifting it himself. Something which has only applied to the Ultimate Universe and not the mainstream one.

  • Loeb, Jeph, ‘Robots in Disguise’ in Ultimates 3 Vol 1 #5 (New York City: Marvel Worldwide Inc., 2008).

Magneto_Ultimatum 4dd6a32938dd62caf51bf9573430d4e1e51262d0

The Red Hulk (AKA: General Thaddeus E. “Thunderbolt” Ross), who used the weightless environment of space to swing the hammer. Something which did not endear the character to Thor fans and has been classed under ‘The Worf Effect’.

  • Loeb, Jeph, ‘Rolling Thunder’ in Hulk Vol 2 #5 (New York City: Marvel Worldwide Inc., 2008).


And Wonder Woman (Princess Diana of Themyscira), who while never fought Thor, she temporally wielded the hammer (after Thor lost track of it, following his fight with Captain Marvel, AKA William “Billy” Batson) before her fight with the Mutant X-Man Storm (AKA: Ororo Munroe) and chose to discard it to keep the fight fair, resulting in Wonder Woman’s lose of the fight once Storm unleashed an electrical storm to subdue her. However, it should be noted that the ‘Marvel Vs. DC’ comic series was subject to fan votes and thus cannot be considered cannon, as the results were deiced sorely on a number basis.

  • David, Peter, ‘Round Two’ in Marvel Versus DC Vol 1 #2 (New York City: Marvel Worldwide Inc. and DC Comics, Inc., 1996).



0. As both a Norse and Germanic deity, Thor was associated with many traits by his worshipers, such as: 

  • Thunder, Lightning, Storms, Oak Trees, Strength, Defence, Goats, Weather, Crops, Trading Voyages, Courage, Trust, Revenge, Warfare & Battles, the Protection of Mankind, Hallowing (Sanctification), Glíma (Viking Wrestling), Healing and Fertility. He was also seen as a Patron of Farmers.

1. Joss Whedon, Avengers: Age of Ultron (Walt Disney Studios Motion Pictures, 2015).

  • Vision (Paul Bettany): “It’s terribly well-balanced.”
  • Thor Odinson (Chris Hemsworth): “Well, if there’s too much weight then you lose power on the swing.”

2. Thomas, Roy, ‘Mine — This Hammer!’ in Thor Vol 1 #276 (New York City: Marvel Worldwide Inc., 1978).

3. Simonson, Walt, ‘The Icy Hearts’ in Thor Vol 1 #355 (New York City: Marvel Worldwide Inc., 1985).

4. Straczynski, J. Michael, ‘Victory’ in Thor Vol 1 #600 (New York City: Marvel Worldwide Inc., 2009).

5. Lee, Stand and Lieber, Larry, ‘Thor the Mighty and the Stone Men from Saturn!’ in Journey into Mystery Vol 1 #83 (New York City: Marvel Worldwide Inc., 1962).

6. DeFalco, Tom, ‘The Fateful Decision!’ in Thor Vol 1 #408 (New York City: Marvel Worldwide Inc., 1989).

7. Guggenheim, Marc, ‘Storm Front’ in X-Men: To Serve and Protect Vol 1 #3 (New York City: Marvel Worldwide Inc., 2011).

8. Higgins, Michael, ‘Stardust Miseries (Part 8) – Reach For the Stars’ in Marvel Comics Presents Vol 1 #45 (New York City: Marvel Worldwide Inc., 1990).

9. Jurgens, Dan, ‘Deal with the Devil’ in Thor Vol 2 #2 (New York City: Marvel Worldwide Inc., 1998).

10. Lee, Stan, ‘The Return of Zarrko the Tomorrow Man’ in Journey into Mystery Vol 1 #101 (New York City: Marvel Worldwide Inc., 1964).

11. Lee, Stan, ‘Slave of Zarrko, the Tomorro Man’ in Journey into Mystery Vol 1 #102 (New York City: Marvel Worldwide Inc., 1964).

12. Eliopoulos, Chris, ‘1st Story’ in Lockjaw and the Pet Avengers Unleashed Vol 1 #1 (New York City: Marvel Worldwide Inc., 2010).

13. However, Throg is only wielding a sliver of Mjolnir, that broke off when one of Thor’s mystical goats – Toothgnasher tapped it with his hoof. This sliver become his hammer Frogjolnir.

14. Slott, Dan, ‘Everything You Always Wanted To Know About Awesome Andy But Were Afraid To Ask’ in She-Hulk Vol 2 #14 (New York City: Marvel Worldwide Inc., 2007).

15. Gruenwald, Mark, and Macchio, Ralph, ‘Hark, the Herald Angel Lives!’ in Thor Vol 1 #305 (New York City: Marvel Worldwide Inc., 1981).

16. Ewing, Al, ‘Good Sons Like You…’ in Loki: Agent of Asgard Vol 1 #9 (New York City: Marvel Worldwide Inc., 2015).

17. Remender, Rick, ‘New World Disorder: Chapter 3 – Grinding Halt’ in Avengers & X-Men: AXIS Vol 1 #9 (New York City: Marvel Worldwide Inc., 2015).

18. This was only after having his ‘moral compass’ magically inverted by the inversion spell cast by Dr. Doom (AKA Victor von Doom) and the Scarlet Witch (AKA: Wanda Maximoff) in: 

  • Remender, Rick, ‘The Red Supremacy: Chapter 3 – Good News for Bad People’ in Avengers & X-Men: AXIS Vol 1 #3 (New York City: Marvel Worldwide Inc., 2014).

19. Aaron, Jason, ‘If He Be Worthy’ in Thor Vol 4 #1 (New York City: Marvel Worldwide Inc., 2014).

20. Aaron, Jason, ‘The Woman Beneath The Mask’ in Thor Vol 4 #8 (New York City: Marvel Worldwide Inc., 2015).

21. Lee, Stand and Lieber, Larry, ‘Thor the Mighty and the Stone Men from Saturn!’ in Journey into Mystery Vol 1 #83 (New York City: Marvel Worldwide Inc., 1962).

22. Simonson, Walter, ‘Doom’ in Thor Vol 1 #337 (New York City: Marvel Worldwide Inc., 1983).

23. DeFalco, Tom, ‘The Hero and the Hammer!’ in Thor Vol 1 #390 (New York City: Marvel Worldwide Inc., 1988).

24. Busiek, Kurt, ‘The Brave and the Bold’ in JLA/Avengers Vol #4 (New York City: Marvel Worldwide Inc. and DC Comics, Inc., 2003).

25. Wein, Len, ‘Star Struck’ in Justice League of America Vol 2 #29 (New York City: DC Comics, Inc., 2009).

26. Singer, Ben, and James, Chad, ‘Goku Vs Superman – DEATH BATTLE’ in,

27. University of California (Riverside), ‘Faculty Profile: Suveen Mathaudhu’ in University of California (Riverside) – Department of Mechanical Engineering,

28. Newitz, Annalee, ‘Sorry, Neil deGrasse Tyson, buy you’re wrong about Thor’s hammer’ in,

29. Clarke, Arthur C., Profiles Of The Future: An Inquiry into the Limits of the Possible (Gateway Publishing: Huntingdon, 2013).

Other Sources:


Copyrighted material used under Fair Use, and belong to their respected copyright holders.

Copyright © 2013 – 2015 Patrick Ward – All Rights Reserved.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s