Ramming, Shields, and the Nemesis Fallacy

This article was inspired by a peculiar claim made by some regarding ramming and shields in Star Trek.

Quick Links:  Past Rammings, The Nemesis Event, Conclusions, and Objections

In Star Trek: Nemesis, we get to observe the Enterprise-E rip Shinzon's Scimitar a new one as, in an act of 'confident desperation', Picard orders the ramming of the Reman Warbird.

Ramming events are not a new thing in Star Trek.  We've seen incidents of ramming, feigned ramming, and so on  throughout all the series except TOS.  One curious thing about the Nemesis ramming, though, is that the Scimitar was, a mere two minutes before the incident, reported by Geordi to still have 70% shielding in place.  However, no shields, nor any effect that would suggest shielding, was seen.

And thus, one is faced with a question . . . what effect, if any, did the shields have?  Were they still up two minutes later, or were they down?  If they were down, why?  

Two things ought to be done in order to answer those questions.  First, we'll take a look at prior shield impact and ramming events, to see what we know and can determine about prior canonical representations of such events.  Then, we'll look at Nemesis, specifically, to see what was going on during that particular situation.

Past Rammings 

The following incidents are, to my knowledge, a complete listing of ramming and large-scale physical shield impact events in the Star Trek canon.  (If you know of any others or if I missed one, please let me know).  

If you'd rather not slog through the scene descriptions and pics, you can jump to the Recap.

Example Group I:

(Examples known to involve shields)

1.  "Datalore"[TNG1]:  The Crystalline Entity makes contact with the Enterprise-D shields.  As is made clear in the episode, the shields would have to be brought down completely for the entity to "eat" the life aboard.

As can be seen, the shields visibly glow as a result of the entity brushing against them.

2.  "The Hunted"[TNG3]:   Roga Danar bounces a small Angosian vessel off of the Enterprise-D shields as a diversion.

The shields flash blue briefly, but are indeed visible (indeed, a dim bubble around the ship is observable), when impact with the unshielded vessel occurs.

3.  "Relics"[TNG6]:  The Jenolan (spelled as per the Okudagram) was used by Scotty and Geordi to brace the Dyson Sphere doors open long enough to allow the Enterprise-D to escape.

The ship's shields held (barely) against the door and door mechanisms that Geordi believed could "crush this ship like an egg", sparkling and flaring the entire time.

4.  "Preemptive Strike"[TNG7]:  Picard orders Data to allow Ro's "trick" of flying through a claimed burp in the shields.  

The shields glow as the Maquis ship is allowed to pass through.  

5. "A Call To Arms"[DS9-5]:  A Cardassian vessel's suicide run against the station results in the ship's destruction against the shields. 

DS9's exact shield configuration in this episode is something of a mystery (there's a bubble around the habitat ring and central core as seen above, but around the docking ring and crossover bridges any shields would have to be conformal, judging by the interaction with weapons).  Nevertheless, one can see quite well that the ramming incident produces a visible shield glow.

6.  "The Raven"[VOY4]:  Seven of Nine uses her shuttle to ram three Bomar ships as part of her escape.

The shields of the shuttle are quite visible even in the aftermath of the impact, and the Bomar ship's shields are also seen.

7.  "Drive"[VOY7]:  The Delta Flyer ends up "scraping" shields at least twice with Assan's vessel, and once with Irina's . . . and we hear reports of Assan colliding with her several additional times.  In the case of the Flyer, her first scraping incident produces shield glow effects as seen elsewhere, and her second (and third) scrape against the ships of Assan and Irina produces the following effect, similar to the one seen earlier:

Now, in the case of the above shot, Torres had reversed the deflector polarity in order to repel the other vessel's shields.  Arguably, it might be a non-standard event . . . but it looks an awful lot like the others, as well as the non-technobabbled scrape seen earlier.  Also note that scraping shields is identified by Paris as an old Academy trick.

8. Star Trek: Generations:  The Duras sisters' photon torpedoes produced a glow area in the Enterprise-D's shields as they penetrated.  Torpedoes are shielded objects, so this would count as a shield-shield interaction event.

9.  Star Trek: Nemesis:  When a flying piece of a destroyed Valdore Class Warbird struck the Enterprise's port saucer, bouncing to collide against the port nacelle, the shields visibly glowed:

Example Group II:

(Events involving questionable or negative shield status)

1.  "Cause and Effect"[TNG5]:  At the Typhon Expanse, the Enterprise-D encounters what Worf refers to as a highly-localized distortion in the space-time continuum.  This proved to be primarily a special temporal distortion that, when it fluctuated, disabled the ship's main power, shields, and other systems.  Most importantly, it spat out the 90 year old starship Bozeman on a collision course.  If the ships collided, the explosion would result in a temporal causality loop . . . the events leading up to the explosion, in other words, would repeat almost precisely.  We get to see the collision occur more than once, and there is no evidence of shielding . . . which is logical, since Worf reports shields are inoperative in at least one loop, and the temporal distortion's effects on the ship were consistent throughout.

The Enterprise was trapped in the loop for 17.4 days, which, given the repeat of what seemed to be about 12 hours of activity from poker game to collision, means that the Bozeman collided with the Enterprise over 30 times, and caused the destruction of the ship on each occasion. 

2. "The Jem'Hadar"[DS9-2]:  The destruction of the Odyssey by Jem'Hadar kamikaze is unaccompanied by any shield effect.   Earlier in the battle, though, we saw Captain Keogh divert shield power when they proved useless in this first encounter with Dominion polaron beams, rendering the unfortunate lack of shields unsurprising.  The shields were not up.   As Sisko puts it, the Jem'Hadar were just trying to show the Federation how far they were willing to go.

3.  "Sacrifice of Angels"[DS9-6]:   A Klingon Bird of Prey is damaged by fire from a Jem'Hadar warship in the final scene we see of the battle.   A wing is lost, and the out-of-control BoP collides with a Jem'Hadar battleship.  The battleship's bow was already in the process of disintegrating due to enemy fire, so this is evidently a collision of two unshielded ships:

4.  "Tears of the Prophets"[DS9-6]:  Against an apparently-fresh, numerically-superior force of Klingon ships, the Jem'Hadar kamikaze maneuvers were quite successful, performed without impediment.  No shield glow was present on some of the Klingon ships, though others did show one.  (See Objections)

The length of time between the opening of combat with the Jem'Hadar and the collision events is not clear.  When we first see the battle, the ships are already well within visual range (which, given the diminutive nature of Jem'Hadar fighters, isn't going to be long), and firing is occurring from both sides.   Given canonical weapons ranges, this offers plenty of time for additional exchanges of fire, in which case one could suppose that the Klingon ships which were rammed were those without shields.  This is further supported by the fact that, at the time of the rammings, some Klingon ships have maneuvered around and behind the Jem'Hadar ships, and the bugs were losing parts to Klingon weapons fire. 

In any event, the rammings and combat "disable or destroy" 15 of Martok's starships, according to Martok.

4a.  "Tears of the Prophets"[DS9-6]:  A damaged Klingon Bird-of-Prey collides with one of the Cardassian defense platforms of the Chin'toka system, shearing off the BoP's wing and perhaps damaging the platform.

As you can see, there is no shield effect present on the platform, which demonstrated gold-colored bubble shields against all weapons fire.   I say that the platform is "perhaps" damaged since we don't see any damage, and almost all the debris which flies past is of a Klingon green color.  On the other hand, the platform is enshrouded by explosion by the next frame after the above one, and its orientation swings rather severely in the direction of the Bird of Prey.

It isn't perfectly clear what's going on here shield-wise, though, since the weapons fire of the Bird of Prey causes a different shield effect pattern . . . in all other shots (those powerful Romulan disruptors, Galaxy Class phasers, et cetera) the shields disappeared instantly when the weapons fire stopped hitting it.  However, against this dinky Bird of Prey, the shields continued to shimmer and flicker even after the last shot, suggesting possible failure.   Even if we assume the platform was destroyed, one wonders whether the shields were even up.  

This question seems answered by the next event from the same episode:

4b.  "Tears of the Prophets"[DS9-6]:  Once again, a Bird of Prey gets beaten down.  Debris from the ship rains down on the shielded asteroid powering the weapons platforms, disintegrating against it.  The most noteworthy piece of disintegrating debris is the starboard wing of the Klingon ship, nicely visible in the lower right on the last three of the following images of the event:

The sparkly shield effect (not unlike the mottled sparklies of the shuttlecraft shields in "The Raven", and just like the weapons fire dissipation effect on the weapons platforms) is quite visible in this impact scene, and was also visible in the weapons fire against the asteroid.  This suggests that, in reference to the BoP-platform collision, either the impact was between ship and shield with no damage to the platform (with the shield impact glow presumably clouded by the BoP's wing explosion), or the shield was down altogether.

(Technically, this particular example belongs in the first group, but I place it with the other examples from the same episode for clarity.)

5.  "What You Leave Behind"[DS9-7]:  A re-use of the CGI elements from "Tears of the Prophets" of the Dominion ships ramming three Klingon ships.   As this occurs well into the battle, we once again have the option of taking a good guess at the Klingon vessels' shield status.   Also note that, once again, at least one of the Dominion ships was damaged by weapons fire from a Bird of Prey before impact, reinforcing the shieldlessness.

6.  "Year of Hell"[VOY4] (alternate timeline):  After almost a year of being kicked around like a soccer ball, Voyager and allies attack Annorax's temporal weapon-ship.  Sabotaged from the inside, the weapon-ship's temporal core is disabled, causing it to fall back into normal space-time.   Voyager and fleet suffer badly against the weapon-ship's conventional arsenal, which seems to pass right through the reconfigured "temporal shields":

A fierce volley from the weapon-ship directly hits the alien cruiser above Voyager, damaging it severely and causing it to list into the Voyager shipwreck.  The ships scrape hulls directly, with no shield effects seen (temporal shields were seen to be a bubble in Part One).  Moments later, the entire fleet has been disabled, as reported by Tuvok.   This, however, is not an instance of total shield failure on the part of the ships, since Janeway orders the fleet to take its temporal shields offline at this point.  Were these normal shields, one would expect disabled vessels to have experienced shield failure already.  

In any event, Janeway's order was made so the timeline will be restored (hopefully) when she does this:

6a.  "Year of Hell"[VOY4] (alternate timeline):

The battered starship, with all the apparent structural integrity of a crumpled wad of paper, rams into the weapon-ship.   Once again, no shield effects are seen, which on the Voyager side is not surprising . . . Janeway ordered shields dropped.  It is not known whether the weapon-ship had conventional shielding, however, since its primary defense was normally to exist outside normal space-time.  This, then, would seem to be an instance of collision between two unshielded objects.

Recap:

Let's review.  And, while we're at it, let's add a mark to each example, so we can easily count them up later:

I.1 - "Datalore"[TNG1]:  A shield interaction against a physical object produces a glow.   (SP-G)

I.2 - "The Hunted"[TNG3]:  A shield interaction against a physical object produces a glow.  (SP-G)

II.1 - "Cause and Effect"[TNG5]:  A shield-free interaction produces no glow.  (PP-nG)

I.3 - "Relics"[TNG6]:  A shield interaction against a physical object produces a glow.   (SP-G)

I.4 - "Pre-emptive Strike"[TNG7]:  A shield interaction against a vessel (shield status uncertain) produces a glow.  (Sx-G)

II.2 - "The Jem'Hadar"[DS9-2]:  No glow is seen on the ship without shields.   (Px-nG)

I.5 - "A Call to Arms"[DS9-5]:  A shield interaction against a physical object produces a glow.   (SP-G)

II.3 - "Sacrifice of Angels"[DS9-6]:  A collision of two shieldless objects shows no glow.   (PP-nG)

II.4 - "Tears of the Prophets"[DS9-6]:  

Ramming by ships, at least one of which is shieldless, against ships of uncertain shield status produces no glow.  (xP-nG)

A collision by a shieldless ship against an object that ought to produce glow against collision shows nothing definite glow-wise.  (It may have lost shields, as seen by the shield's behavior before impact, or else the explosion around the small object may have obscured our ability to observe any expected shield glow.)   (SP-x or PP-nG)

An unshielded object's collision against a shielded object produces a shield glow. (SP-G)

II.5 - "What You Leave Behind"[DS9-7]:  Ramming by ships, at least one of which is shieldless, against ships of uncertain shield status produces no glow.  (xP-nG)

I.6 - "The Raven"[VOY4]:  A shield interaction against another shielded object produces a glow.  (SS-G)

I.7 - "Drive"[VOY7]:  Shield interactions against other shielded objects produce a glow.  (SS-G)

II.6 - "Year of Hell"[VOY7]:

An impact between objects with reconfigured temporal shields produces no glow.  (SS-nG)

An impact between two unshielded objects produces no glow.  (PP-nG)

I.8 - Star Trek: Generations:  Shield interactions against other shielded objects produce a glow.  (SS-G)

I.9 - Star Trek: Nemesis:  Shield interactions against an unshielded object produce a glow.  (SP-G)

Final Tally:

Note that the marks below are in the form of "Shield Status of Defender""Shield Status of Collider"-"Glow/No-Glow"

SS-G:    3
(Shield-Shield interaction produces a glow on both parties' shields in three cases)

SP-G:    6
(Shield-noShield interaction produces a glow on the defender's shields in six cases)

Sx-G:    1
(Shield-Unknown interaction produces a glow (in the shielded ship) in one case)

SP-x or PP-nG:  1
(The uncertain case regarding the platform vs. BoP in ToTP, enshrouded by explosion.  Probably PP-nG.)

PP-nG:    3
(noShield-noShield interaction produces no glow in three cases (no surprise), not counting the extra 30 of CaE)

Px-nG:    1
(The Odyssey ramming . . . no shields on Odyssey, and the JH bug exploded too quickly to see if its conformal shields, if even up, produced a glow.)

xP-nG:    2
(Collisions involving one shieldless object and an object of uncertain shield status produce no glow on two occasions.  Note, however, that both of the xP-nG cases (ToTP and WYLB, especially) involve defending ships that have been in fleet combat for some time, so these are likely PP-nG events.)

SS-nG:    1
(A collision between two shielded objects produces no glow in one case . . . both ships are known to have reconfigured for temporal shielding, meaning these are not standard shields)

As you can see, in all ten instances where we know that a ship has standard shielding, an impact with something (whether shielded or not) produces a glow.   In the four instances where we know the defender has no shields, there is no glow on the defender's part.    

In short, one can see the clear pattern . . . if there's a shield on the defender's ship, we're gonna see it.  (This is similar to forcefields on the interior of starships, which invariably glow when touched, even in TOS or ENT.)  The only exceptions would be in regards to a shield that we simply can't see due to something obscuring it, or shields that are configured in a peculiar way and thus seem to have no effect in regards to conventional weapons or impact.

Now that we've thoroughly considered these prior cases, let's take a look at Nemesis.

The Nemesis Event

As mentioned previously, two minutes before the ramming occurred the Scimitar was said to have 70% shielding.  Let's take a closer look at the events before the ramming (in screen time), paying particular attention to the shields.  The moment of contact between the ships will be considered to be Time Zero (T).

T minus 17 minutes, 20 seconds:   The battle begins.

T minus 14 minutes, 25 seconds:   Shinzon, via holographic proxy, tries to get Picard to lower shields and allow himself to be beamed to the Scimitar.

T minus 11 minutes, 50 seconds:   Donatra's Warbirds decloak, soon to join the battle.

T minus 10 minutes, 18 seconds:   Aft shields drop to 40%.  Riker orders the bow kept on the Scimitar, and auxiliary power to forward shields.

T minus 9 minutes, 45 seconds:   Shinzon's disruptor fire blows off the starboard wing of the second Romulan ship.  

T minus 9 minutes, 42 seconds:   The wing section slams into the port side of the saucer, and then bounces to hit the port nacelle.   Shields flare in the struck areas.

T minus 9 minutes, 38 seconds:   Data reports forward shields down to 10%.  As these were not the shields that were hit, and given the Scimitar's likely location (it had been right behind the clipped Warbird on the Enterprise's port side, gaining rapidly), we must assume this was due to Scimitar weapons fire from ahead of the E-E.  In any case, Riker orders "bring us about."

T minus 8 minutes, 40 seconds:   Shinzon, having partially dropped his cloak and lured Donatra in, disables her ship with a fierce volley of weapons fire.  He is now left to concentrate on the Enterprise.

T minus 7 minutes, 0 seconds:   Data reports structural integrity loss on decks 12-17, sections 4-10, after another series of hits from the Scimitar.  Emergency forcefields are put in place (Geordi reports that they're holding just four seconds after Data's report), and then those areas are evacuated with forcefield power to be rerouted to forward shields.

T minus 6 minutes, 16 seconds:   Quantum torpedoes, targeted by Deanna, strike the Scimitar's forward upper areas.  A run by the Enterprise continues to pummel that area.   A running firefight ensues, the Enterprise's rear weapons firing on the Scimitar's bow and vice-versa.

T minus 5 minutes, 35 seconds:   Part of the background chatter is a voice saying "impulse out".  This is the same voice that will later report the impulse engines restored.   Data reports ventral shield loss, leaving the lower deck of the Engineering section exposed.  Though Picard orders power diverted to compensate, Reman troops board the ship.

T minus 3 minutes, 8 seconds:   A volley of fire from the Scimitar includes a hit to the bridge, resulting in its brief exposure to space before the forcefield appears.

Now we're close to the fun part . . .

T minus 2 minutes, 21 seconds:  Picard asks for a report.  
T minus 2 minutes, 20 seconds:  Data responds:  "We have exhausted our complement of photon torpedoes.  Phasers banks are down to 4%, sir."
T minus 2 minutes, 15 seconds:  Picard:  "What if we targeted all our phasers in a concentrated pattern?"
T minus 2 minutes, 12 seconds:  Geordi:  "The Scimitar's shields are still at 70%.  It would make no difference, captain."   Geordi reports this off of a screen which shows a top view of the Scimitar.  It has a complete oval shape around it, even though the Scimitar has hull-hugging conformal shielding like the Enterprise-E.

T minus 2 minutes, 0 seconds:   Everyone starts to notice, out of the new bridge window, that the Scimitar is just hovering in front of them.   Deanna asks "what's he doing?", and Picard figures out that Shinzon "wants to look me in the eye.  We've got him!  He thinks he knows exactly what I'm going to do."
T minus 1 minute, 29 seconds:  Picard:  "Geordi, divert all power to the engines.  Take it from life support if you have to . . . give me everything you've got."
T minus 1 minute, 21 seconds:  One of the bridge chatterers says "Impulse power capability's been restored."  A moment later, Geordi reports "Ready, Captain."
T minus 1 minute, 4 seconds:  Shinzon, having hailed the ship, asks Picard:  "Don't you think it's time to surrender?  Why should the rest of your crew have to die?"
T minus 36 seconds:   "Engage."
T minus 27 seconds:   The Enterprise-E, battered but unbroken, begins sliding toward the Scimitar.
T minus 14 seconds:  Shinzon, at first looking confused but now seemingly amazed, orders "Hard to port!" to no avail.

Impact.

A minute and 23 seconds later, Shinzon orders "Divert all power to the engines . . . full reverse".  The ships separate.

After Picard discovers that the Enterprise's self-destruct is not operational, Shinzon orders deployment of the thalaron weapon.  Picard then beams over to stop it.

Obviously, by that point, the Scimitar was without forward shields, at least.  The question is, what exactly made them fall?  Let's look at some of the numerous theories that have been fielded to see what makes the most sense:

1.  Trek shields do not stop impacts.  

Wrong . . . we've already seen why, even in this very movie.

2.  The Scimitar's shields were unable to stand up to the impact of the Enterprise.  

Also wrong, and we've already seen why, even in this very movie.   But, this is the absurd claim, oft-repeated and even used as a basis for some baseless calculations that inspired this page's existence.  As seen, the concept ignores shield impact seen in the Trek canon (though the proponents usually claim the bug-BoP rammings from "Tears" as fully shielded incidents, claiming support while ignoring every other example).

The Scimitar's shields simply were not there.  There is no flare, no sparkle, no glow . . . and yet, in every other way, these shields behaved precisely as those of the Enterprise.   Where did they go, and why?   The following ideas recognize the lack of shields, and try to explain it:

3.  The "hole":    The Scimitar shields, at 70%, were not covering the forward arc.  In other words, the 30% missing was basically at the front.

Though conceivable, this concept would seem contrary to Geordi's comment that concentrated phasers would make no difference . . . he seemed to be speaking of phasers vs. shields.  One would not imagine the phasers, even if they were severely limited in power, being absolutely useless for a few shots against bare hull (before the Scimitar eliminated them).  Also, if Geordi's tactical analysis screen with the tag on the front of the oval was a shield scan, then this idea seems less likely.

On the other hand, the area of the forward shields had taken quite a pounding, there at the end.

 4.  Shinzon had lowered the shields.

This idea has quite a bit of merit, but there are still some hang-ups.   As Picard says, "he thinks he knows what I'm going to do" . . . Shinzon could very well have dropped his shields in overconfidence, awaiting Picard's surrender and planning to beam him and any remaining Reman troops aboard the Scimitar.

However, there are 27 seconds between the Enterprise's start of forward motion and the hit to the Scimitar.  Shinzon's "hard to port" order comes in at 14 seconds before impact . . . this means that Shinzon must've known what was going on for at least 14 seconds.   If his shields were down, ought he not have tried to raise them?   One would think so.   Also, one would think that Picard might've tried his phaser idea before taking the fight to the enemy in such a literal fashion.

(I commonly loathe the idea of claiming a character is behaving incompetently . . . it's too often used as an easy escape route by those who look for the easy way out of an argument.   But, in this case, the idea has some value . . . after all, even his "hard to port" order was silly . . . why not try to move backward and limit the amount of damage?  Why turn to port, which potentially exposes the thalaron weapon's starboard targeting arms, or the warp nacelles, to damage?  

On the other hand, there might've been some reason he couldn't re-raise shields in 14 seconds . . . that constitutes a more likely scenario, and avoids the incompetence argument.)

5.  Insert technobabble.

Version One - Threshold:   There was a threshold to the Scimitar's shields, either in regards to the focus of the attack or the energy of it.   

The focus idea doesn't work that well.   While it's true that one would expect to be attacked with weapons that have a high intensity but a low profile (thin phaser beams, small torpedos, etc.), there's nothing to suggest that the Scimitar's shields would let something wider through, like a cosmic ray burst or a saucer section of a starship.   Though the Enterprise's saucer isn't quite pointy, it isn't exactly blunt, either.   Further, Picard would've had to have known about this weakness in advance, and there's nothing in prior canon to suggest it.

The energy threshold idea is better, but still extremely shaky.  If the shields won't try to stop an amount of energy that's able to gouge a huge gash in the ship, they're hardly worthwhile. 

Version Two - SIF:   The Enterprise's structural integrity field might've allowed passage through the shields, perhaps having been tuned to do so en route to the impact.  

This makes little sense . . . how would they know what to tune the SIF to?  One would expect this to be equivalent to Soran's maneuver in Generations that allowed penetration of the Enterprise-D shielding.  In other words, it's no small thing to do . . . you basically have to have knowledge transmitted from within the shielded ship.

While it's true that Data had been aboard the Scimitar posing as a trusted android hours before, there's no reason to assume he accessed the Scimitar's shield frequencies, only to employ them long after they were needed.

And, last but not least, one would expect the shields of the Scimitar to have glowed a la the Enterprise-D shields in Generations.

Version Three - The Scimitar's shields:   Worf, in his tactical analysis of the Scimitar when it was first observed by the Enterprise, reported "primary and secondary shields".  Perhaps the 70% that were remaining were the secondary shields, and these were configured in some way that precluded their use against impact.

I like this idea (besides the fact that it is mine).  However, there are difficulties with it, too . . . the only similar example involving such a configuration would be the temporal shields in "Year of Hell"[VOY], which were not seen to guard against conventional weapons, either.  Metaphasic shielding, seen twice in late TNG, might also be considered an example . . .  but we've never seen what happens when that shield configuration is fired upon, or collided against.

One could argue that the secondary shields were of the "Best of Both Worlds"[TNG] Borg configuration . . . stopping weapons utterly, yet allowing a shuttle through during the Picard rescue.  However, even the Borg electromagnetic shields flared around the shuttlecraft. 

A similar idea to mine appeared on SpaceBattles, inspired in part by the separate shielding systems of Star Wars.   In this case, the idea was that the Scimitar's primary and secondary shields operated as a single system . . . the outer shields repelling KE, the inner shields halting energy, and at the time of ramming, only the inner shields were up.   However, that idea suffers not only from some of the same issues mine does, but also seems inconsistent . . . if the outer shields are for KE, why did they fail first due to weapons fire?  True, phasers are particle weapons, and one would assume disruptors are, as well . . . but then the 70% shield power of the Scimitar's energy shields would've made no difference against the phasers. 

Version Four - Unseen, Unknown:   Some sort of technobabble was employed . . . no one knows what it was exactly, and it happened when we weren't watching.

Though true in the deepest sense, and quite possible given the technobabbles-of-the-week we've seen, this concept is not tenable in and of itself.

That's an awful lot of ideas . . . but it's little wonder they've appeared, since this is a peculiar case. 

Conclusions

A object's shields will show a luminous effect when collided with . . . the Scimitar shows no such effect, therefore it was unshielded when the Enterprise-E rammed the ship. 

We may engage in all sorts of conjecture to determine how and why this is the case, but the fact remains that it was the case.   All of the conjectures presented have some problems, though some are stronger than others.  We may never know which one is accurate.   The strongest, simplest idea in my opinion would be the notion that the overconfident Shinzon dropped shields awaiting Picard's surrender and transport, and then couldn't get them back up in time.   But that still isn't a perfect solution, if even just because of the fact that no one said anything about it.  

((Stepping out of the canon universe thing for a moment, it would've been far better had the situation been written differently . . . after all, Picard and the Romulans fought the Scimitar without behaving as if they'd ever noticed such a minute drop in his shielding.  Had Geordi responded to Picard's query about concentrated phasers with "he still has (tiny percent) forward shields . . . our phasers would burn out as soon as the shields fell,"  then the situation would not only be far less confusing with reference to the ramming, but would also seem more realistic.   As it stands, the Scimitar is a profound leap in combat starship design . . . capable of going up against a Sovereign and two Valdore-type Warbirds with apparent ease.  And, in the case of the Sovereign, he was specifically targeting her to avoid her destruction!   And yet, these combat systems seem almost an afterthought, compared to the fact that the entire ship seems built around the thalaron planet/fleet-killer.))

In any case, the Scimitar's shields were not up . . . this is another incident of two unshielded ships colliding.

Strangely, some continue to resist the logical conclusion.  See the Objections.

(Update:  The Scimitar's shields are weird.   I'll try to figure out some way to fold this into the current page.)

Many thanks and acknowledgements are in order, as there are pictures here from numerous sources.  I'd specifically like to thank G. Kennedy of www.ditl.org, who was kind enough to discuss and create screenshots for this page from "A Call To Arms" and "The Raven".   Thanks to D. Templar of Flare for a reminder regarding "Cause and Effect".  Thanks are also in order to Janet's Star Trek Voyager Site  for the "Year of Hell" shots and the animation from her "Drive" page, and to the U.S.S. Kyushu site, with its wonderful vidcaps from DS9 from which I created several screencaps.  And, last but not least, Stardock Alpha.