Jets of green light (Was: Accidental Harrycrux with a Bloodsucking Snake)

[justcarol67]

No: HPFGUIDX 155224

Pippin wrote:
> As you say, there are all sorts of other things JKR uses to show
that Dumbledore considers Harry more important and don't set up a
Chekhov's gun. Mentioning the possibility of such an order creates the
expectation that it will be given. The order wasn't given to Harry,
and the only other person under his command that Dumbledore spoke to
before he died was Snape.

Carol:
"Chekhov's gun? Is that the same as "smoking gun"? I've never heard
the expression. (I agree with you that the order almost certainly
relates to Snape for the reasons you stated and because such an order
would go a long way toward clearing up events on the tower.)
> 
Pippin earlier:
> > > It is not an assumption that a blast of green light can be
produced by other spells than AK,
> > 
> > Neri:
> > It is not? I can't recall any other spell in canon that comes with
a green jet of light. For all we know AK could be the only curse of
that color.
> 
> Pippin:
> Hagrid tells the kids  to send up green sparks if they find the unicorn.

Carol adds:
We see the green sparks again as the second signal when the Order
members rescue Harry from 4 Privet Drive in OoP. Ron's apparently
accidental spell, "Eat slugs!" produces green light (somewhere in
CoS), and, more to the point, not all the jets of green light in the
battle of the MoM are necessarily AKs. We don't constantly hear those
words shouted, and we don't know whether an AK can be cast
nonverbally. Even the ones that the narrator labels "another killing
curse" could be something else given Harry's state of mind. But the
best example is the spell that hits Tonks and knocks her unconscious:

"A jet of green light had narrowly missed Sirius; across the room
Harry saw Tonks fall from halfway up the stone steps, her limp form
toppling from stone set to stone seat, and Bellatrix, triumphant,
running back toward the fray" (OoP Am. ed. 803). Afterwards, Tonks is
sent to St. Mungo's to recover, apparently too badly injured for Madam
Pomfrey to heal her.

So either an AK can fail to kill or that spell wasn't an AK.

The Death Eaters at the QWC also send flashes of green light from
their wands when they're levitating the Muggles, but the Muggles
aren't killed and neither is anyone else: "Loud jeering, roars of
laughter, and drunken yells were drifting toward them; then came a
burst of strong green light, which illuminated the scene" (GoF Am. ed.
119). Harry notices that the smallest child's head is flopping limply
from side to side (GoF 120); Dumbledore is described as being limp as
a rag doll. (Can there be a connection here? Does Levicorpus or a
similar spell give off green light?) And of course the light that
erupts from Barty Jr's wand as he casts the Dark Mark is green: "And
something vast, green and glittering erupted from the patch of
darkness Harry's eyes had been struggling to penetrate" (128).

Just because a spell gives off a jet of green light doesn't mean it's
an AK. We're never told the color of some spells, Impedimenta,
Wingardium Leviosa, and Levicorpus among them. Any one of them could
be green.

Carol, snipping the rest of the post because I want to concentrate on
this single point