Pebble Herder Tug – B-Type

Category: [TECHNOLOGY] Type: [Starship, Space Tug, Utility Craft]

1. Summary

The Pebble Herder Tug – B-Type is a relatively small, agile, 120-tonne dry mass utility spacecraft common in asteroid mining operations. Powered by a high-efficiency ion-cluster thruster system, Pebble Herders specialize in maneuvering smaller, sub-kilotonne asteroids (“pebbles”) or individual [UniPod-120 Ore Containers]. Their primary role is to collect these smaller loads from various extraction points or disparate orbits and consolidate them for pickup by larger, less maneuverable haulers like the [Rock Shepherd Tug – A-Type].

2. Data Block / Key Parameters

Relevant Equations/Relationships:

• Acceleration (with payload): $a = F / M_{\text{total}}$
  • Example: With a $180 \, \text{kN}$ thrust and hauling a $500 \, \text{tonne}$ asteroid (plus tug mass & propellant, say total $500+120+30 = 650\text{t}$): $a = 180,000 \, \text{N} / 650,000 \, \text{kg} \approx 0.277 \, \text{m s}^{-2} \approx 0.028 \, g$. This allows for reasonably swift maneuvering of smaller masses compared to a Rock Shepherd.
• The high $\Delta v_{\text{gross}}$ of $12 \, \text{km s}^{-1}$ (when the tug is lightly loaded or only carrying its own propellant) indicates its ion drives are very efficient, allowing it to perform numerous orbital adjustments and rendezvous maneuvers over its operational lifetime without frequent refueling.

3. Narrative Detail & Context

Within the sprawling enterprise of asteroid mining, not every task requires the brute force of a [Rock Shepherd Tug – A-Type]. The Pebble Herder Tug – B-Type fills a vital niche, acting as an agile “sheepdog” for smaller masses. These versatile craft are essential for optimizing the efficiency of the overall [Belt Mining Workflow].

Design & Operational Role: Pebble Herders are significantly smaller and more maneuverable than their A-Type counterparts.

• Ion Propulsion: Their defining feature is a cluster of high-efficiency ion thrusters. While providing much lower instantaneous thrust ($180 \, \text{kN}$ total) compared to fusion drives, these thrusters offer exceptionally high specific impulse. This translates to a large gross $\Delta v$ budget ($12 \, \text{km s}^{-1}$), allowing a Pebble Herder to perform many orbital adjustments, rendezvous maneuvers, and short-range transfers on a single load of propellant (typically Xenon or Argon).
• Cargo Handling: They are equipped with a variety of grappling tools, tethers, and magnetic clamps suitable for latching onto irregularly shaped sub-kilotonne asteroids or for docking with one to three loaded [UniPod-120 Ore Containers].
• Operational Cycle: A common role for a Pebble Herder is to visit multiple small mining sites (perhaps individual asteroids being worked by automated extractors or smaller [Spin-Gravity Drum Processors]) or to collect single UniPods from scattered locations. It then consolidates these “pebbles” or pods at a pre-arranged rendezvous point or a local collection depot, where a larger Rock Shepherd can efficiently pick up a full, multi-kilotonne load. This division of labor prevents the inefficient use of large tugs for small, scattered pick-ups.
• Automation & Crew: With a small crew of just two (often a pilot/remote systems operator and an engineer/technician), Pebble Herders rely heavily on sophisticated auto-pilot systems and teleoperation capabilities for routine tasks like station-keeping, slow rendezvous maneuvers, and managing multiple tethered loads. This high degree of automation is possible with secure, dedicated onboard processing, adhering to post-[Wildcode Crisis] safety principles for critical systems.

“Used Future” Feel: Pebble Herders are the nimble utility vehicles of the asteroid belt. They might appear more “scratched and dented” than larger tugs due to more frequent close-quarters work around irregular asteroids. Their ion drives would emit a faint, characteristic blue glow. Their grappling arms and tether winches would be well-worn. The cockpit would be compact, filled with multi-function displays (with robust, tactile backup controls) and offering excellent panoramic visibility for tricky maneuvers.

4. Canon Hooks & Integration

• Feeder System for Large Haulers: Crucial for the economic viability of mining operations that target numerous smaller or dispersed asteroid bodies.
• High Maneuverability & $\Delta v$: Their ion drives give them the ability to operate efficiently across a wide range of minor orbital adjustments, making them ideal for “tidying up” an asteroid field or managing local depot logistics.
• Short-Range Specialists: Not typically used for the long interplanetary hauls undertaken by Rock Shepherds, but rather for intra-belt or local cluster operations.
• Potential for Independent Operations: A small mining consortium or a group of independent prospectors might operate a Pebble Herder as their primary means of collecting and transporting small batches of high-value ore.
• Search & Rescue / Utility Role: Their agility and long operational endurance (due to efficient ion drives) could also see them used in search and rescue operations for stranded personnel or as general-purpose utility craft in remote mining camps.

Story Seeds:

1. A Pebble Herder crew, while consolidating a load of seemingly ordinary iron-rich “pebbles,” discovers one of them contains an unexpectedly high concentration of rare earths or even a unique, unknown mineral. They must decide whether to report it immediately (risking a corporate claim-jump) or try to secure it for themselves.
2. During a complex multi-asteroid herding operation, a Pebble Herder’s primary ion thruster suffers a critical malfunction. The two-person crew must use their remaining maneuvering thrusters and clever orbital mechanics to safely corral their valuable (and now drifting) cargo before it becomes a hazard.
3. Pirates begin using modified Pebble Herders as surprisingly agile (though lightly armed) raiders, targeting isolated UniPods or small mining outposts that larger pirate vessels might ignore.
4. A Pebble Herder on a routine collection run stumbles upon a derelict [Dragonfly Scout Drone] that has captured anomalous data, pulling them into a larger mystery.

5. Sources, Inspirations & Version History

• Primary Source: o3 & tel∅s Notes (Asteroid & Resource Extraction Infrastructure Stack - Transfer Tug classes; Pebble Herder Tug – B-Type tech-wiki entry).
• Inspiration: Real-world ion propulsion technology (e.g., NASA’s Dawn mission, Hall thrusters), concepts for smaller utility spacecraft, and the logistical challenges of managing numerous small payloads in a distributed environment.
• Version History:
  • v0.1 (2025-05-13): Initial draft by Gem (2.5 Pro).