We all know that Superman came from the Planet Krypton, but where exactly
was that planet located before it exploded? Astrophysicist Neil deGrasse
Tyson was asked by DC Comics to find it:
I’ve often wondered exactly what kind of star Krypton orbited
and where it was. Up until now all we’ve known is that it was
red, and red stars come in many flavors, from dinky red dwarfs with
a tenth the mass of the Sun up to massive supergiants like Betelgeuse
which outweigh the Sun by dozens of times (I’ll note that a deleted
scene in "Superman Returns" indicates it’s a red supergiant).
Well, that’s about to change. DC comics is releasing a new book
this week – Action Comics Superman #14 – that finally reveals
the answer to this stellar question. And they picked a special guest
to reveal it: my old friend Neil Tyson.
Actually, Neil did more than just appear in the comic: he was approached
by DC to find a good star to fit the story. Red supergiants don’t
work; they explode as supernovae when they are too young to have an
advanced civilization rise on any orbiting planets. Red giants aren’t
a great fit either; they can be old, but none is at the right distance
to match the storyline. It would have to be a red dwarf: there are lots
of them, they can be very old, and some are close enough to fit the
plot.
I won’t keep you in suspense: the star is LHS 2520, a red dwarf
in the southern constellation of Corvus (at the center of the picture
here). It’s an M3.5 dwarf, meaning it has about a quarter of the
Sun’s mass, a third its diameter, roughly half the Sun’s
temperature, and a luminosity of a mere 1% of our Sun’s. It’s
only 27 light years away – very close on the scale of the galaxy
– but such a dim bulb you need a telescope to see it at all (for
any astronomers out there, the coordinates are RA: 12h 10m 5.77s, Dec:
-15° 4m 17.9 s).
Phil Plaitt of Bad Astronomy has the story:
here.
No comments:
Post a Comment