# Downports and landing non streamlined ships.

I've seen reentries: the question would be how much energy is created and how does that translate into Traveller measurements.

E=mc^2 for the entirety of the pressure wave, up until your ship explodes from the excess energy in the capacitors.
In an unpowered landing, the atmosphere imparts enough energy for your ship to burn up before it hits the ground, so in your unpowered black globe drop, your capacitors are hit with enough power to melt your ship... and then there's a whole different discussion over whether what is essentially a black hole with no gravity well generates friction as it sucks in the pressure wave on the way down. You might just turn off the globe only to slam into a wall of thicker atmosphere the same speed as your initial de-orbit.

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Our fusion plants do output a lot of energy, and the capacitors are two hundred fifty percent plus.

If you are absorbing the energy from the pressure wave, and thus there is no friction, there is no terminal velocity.
At that point, terminal velocity refers to the minimum speed expected to kill you upon impact.

In the LBBs, most of us inferred that the power plants went into overdrive to burn all of that refined hydrogen to power the jump drive. Now we know it only needs one turn of power plant activation, at about equal to no more than double the M-drive rating of a balanced normal ship. The rest is dumped to inflate the bubble. That means that the energy of conversion is a few Dton's liquid hydrogen. Far less than the stuff in your path in an atmospheric insertion.

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Without friction, there is no heat, and therefore no energy to absorb.

At unrestricted velocity, timing as to when to turn off the Black Globe becomes tricky.

The reason for no friction, would be the unrestricted absorption of the molecules in the pressure wave, or rather all of the atmosphere the craft contacts in its decent. Thus all of that air being converted to energy using E=Mc^2.
Timing? Very predictable. Either program an auto shutoff prior to exceeding critical charge, or the lack of friction allows the ship to be drawn closer by gravity at the predictable rate of a planet without an atmosphere. So you'll know when you need to act in order to not hit the planet.
Not blowing up anyway is the trick.

You don't want to push your luck.

Without friction, there is no heat, and therefore no energy to absorb.

At unrestricted velocity, timing as to when to turn off the Black Globe becomes tricky.
No.
As the ship falls through the atmosphere the molecules of the atmosphere contact the globe, they then dump all their energy into the globe - energy from pressure, momentum, and the like. Since the globe absorbs this energy then there is no 'air resistance' force to slow the ship, it just keeps getting faster, hitting yet more atmospheric molecules until it hits the ground at which point things get really interesting.

The original CT HG80 allows for a ship to jump into a system with its globe already up, it then moves according to its vector on emergence modified by 'real' gravity within the system. The tactic can not work as described unless this is so.

1. I've come to the conclusion that the Black Globe might be a controlled black hole.

2. The void of space tends to have less molecular density than a planetary atmosphere.

3. So it absorbs matter, the molecules present in it's line of descent.

4. The question would be, translated into Traveller measurements, how much energy does that actually represent.

5. Also, there are ground based installations with Black Globes.

Really, ground based black globes? Where are they mentioned?

I'm pretty sure I've tracked that down once, and posted it somewhere.

As a matter of courtesy I've searched through various forums, and looked at the list of Classic booklets, which likely would have to have been printed immediately after High Guard, but then I thought, screw this.

I think I'll just start making copies of interesting pages (and rules) and bundle them into a reference pdf, which will simplify these matters in future.

If I stumble across that reference at a future date, I'll post it.

I have found it - T5 version 5.09
The Star Marine Guards defending the Imperial Embassy on Arden during the Fifth Frontier War retreated to a Black Globe Safe Room when locals stormed and burned the compound. The 100-meter diameter globe neatly sliced through walls (and a few attackers) to envelope about a quarter of the installation. Over the course of a month, it resisted fire, bombs, and other attacks. When forces from the Imperial Fleet arrived, they used a coded laser to signal the interior that all was finally safe, but to confirm the signal, an outside Marine tapped the rhythm to the Marine song: tap-tap-tap, tap-tap-tap, tap-tap-tap-tap tap. The interior Marines deactivated the barrier, happy at the prospect of eating something other than stored rations.

I have found it - T5 version 5.09
The description seems to fly in the face of how a black globe is supposed to operate - that it absorbs energy and that energy has to go somewhere or else the capacitors explode. It would also (I believe, stop the transference of atmosphere between the inside and out - thus the saferoom would have to have life support equipment since it would be 100% cut off from the outside). The only place for them to get rid of the energy would be to power up things since they have no weapons to fire out with.

Since it's supposed to absorb energy, it should easily handle fire. Though with no flickering or major usage of the stored energy in the capacitors the attackers should be able to overwhelm the defenders if they wanted - especially if nobody was shooting at them to stop them from continually charging the field.

Sometimes things sound cool, but the explanation requires too much head scratching to make it work.

I agree, that passage I quoted flies in the face of other canonical rules and statements concerning black globes. Every atmospheric molecule should lose its energy to the globe when it strikes the boundary, you would end up with a very weird zone around the globe filled with atmospheric ice and subliming gas...

The only logical way the quoted passage can work is if the safe room globe has an enormous energy sink...

I'm pretty sure this stuff predates Tee Five, which is why I didn't check there.

However, I did look up venting, with three hits, one irrelevant and the other two applying only to (Black) GLOBE ENERGY CAPTURE:

Liquid Hydrogen Venting applies EP to the ship’s stored fuel. Applying 11 EP (11 Hits) raises the fuel temperature +11 and it converts to Hydrogen Gas, which is vented outside the hull (although still within the Globe).

Theoretically, nearly all of the ship’s Fuel can be used to sequester energy at the rate of 11 Hits per ton.

`

The problem with hydrogen venting for jumping is that's it's incompatible with Collectors.

Emm, no,

1 EP is how much energy? How much energy is required to raise the temperature of liquid hydrogen by 1K?

Or try this - how much damage can 1 EP cause if it is transmitted by a laser or particle beam? Enough to heat 1 ton of liquid hydrogen to a gas? So why not just pump liquid hydrogen around your hull to soak laser and particle beam hits?

Why can't you see out or shoot out from a black globe? What happens if you fire a laser inside a black globe...

I'm pretty sure this stuff predates Tee Five, which is why I didn't check there.

However, I did look up venting, with three hits, one irrelevant and the other two applying only to (Black) GLOBE ENERGY CAPTURE:

Liquid Hydrogen Venting applies EP to the ship’s stored fuel. Applying 11 EP (11 Hits) raises the fuel temperature +11 and it converts to Hydrogen Gas, which is vented outside the hull (although still within the Globe).

Theoretically, nearly all of the ship’s Fuel can be used to sequester energy at the rate of 11 Hits per ton.

`
The only problem here is that (a) physics says if you vent hydrogen inside your globe you raise the pressure of it, and (b) hydrogen is contraindicated for breathing (plus it's rather explosive when combined with oxygen and a spark...).

For a facility on the ground, with roughly half of the area of the sphere being the ground, venting hydrogen into the bubble would be considered a "bad idea". Since in the passage it's not flickering, then the gaseous hydrogen would continue to increase the atmospheric pressure inside the bubble, making it hazardous to human life.

I get the idea... but the explanation and operations of such a thing leave a lot to be desired from a logical or workable perspective. And too much handwavium means you might as well say "the field is powered by flubber" - a Disney-esque handwavium magical material. Pournelle had something similar, called the Langston field, that worked much better. It still absorbed energy, but your generators defined the field, thus you could have ground-based fields without issue. Plus the physics of them made sense - they radiated away energy - slowly, but as they absorbed energy they expanded, up to the point of getting gaps in the field so you could 'see' the target beneath and hit it directly.

The Mote in God's Eye by Niven and Pournelle was published in 1974 - 3 years before CT was published. So I wonder if the idea for black globes came from there.

The original black globe in 79 High Guard was very much like the Langston Field.

A lot of this is a question about where the heat, energy, or hydrogen, goes.

And flubber would be great for a belly landing, if you convert the impact energy into something else besides momentum.

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