Celestron 93585 PowerTank Glow 5000 USB Rechargeable Power Bank Red Astronomy Flashlight 5000mAh Review (2026)

A two in one tool for the observing field

The PowerTank Glow 5000 combines a rechargeable red LED flashlight with a small USB power bank in one IP65 rated body, aimed at observers who want a single accessory instead of carrying a separate flashlight and battery pack. A single button controls both functions, with short presses cycling the red flashlight through three brightness levels and off, while a press and hold turns device charging on and off. Two silicone straps are included so the unit can be mounted directly to a tripod leg, keeping it within reach during a session rather than sitting loose in a pocket or bag, and a wrist strap is included as well for handheld use.

Flashlight performance and night vision

Like other dedicated astronomy flashlights, the red LED here is meant to let an observer read star charts, adjust eyepieces or walk around a dark site without disrupting night vision the way a white light would. Three brightness levels give some flexibility between a dim glow for chart reading and a brighter setting for packing up gear, controlled through repeated short presses of the single button. Because the flashlight and battery pack share one button, users need to be mindful of press duration so they do not accidentally start or stop charging while only trying to cycle the light, though in practice the distinct short press versus press and hold pattern is easy to learn after a session or two.

Power bank capacity and charging

The internal battery holds 5000 mAh, rated at 25 Wh, and outputs 5 volts at up to 1 amp through its USB port, enough to top up a phone or run a small USB accessory like a dew heater strap for part of a night. Recharging the PowerTank itself takes about 3.5 hours from a 5V, 1.8A source, and the manufacturer rates the internal cell for a minimum of 500 charge cycles. This capacity is well below dedicated telescope power packs built to run equatorial mounts, so buyers who need to power a motorized mount overnight should look at a larger dedicated power tank rather than this compact flashlight and phone charger combo.

Build quality and included accessories

The unit measures about 5.5 by 1.3 by 1.3 inches and weighs 6.3 ounces, small enough to tuck into an eyepiece case, and carries an IP65 rating for resistance to dust and splashing water, useful for dewy nights at a dark site. Covered input and output ports protect the connections when not in use, and overcharge protection guards the internal cell if it is left plugged in longer than needed. The package includes the flashlight and power bank unit itself, a USB charging cable, a wrist strap and two silicone mount straps for attaching it to a tripod leg, so it arrives ready to mount and use without extra purchases.

Verdict and how it compares

This is a practical grab and go accessory for observers who want a red flashlight with a bit of emergency charging capacity built in, and it sits just behind Celestron's own dedicated red headlamp and Carson's RedSight flashlight in a head to head comparison of red astronomy lights, with its closest rival being Celestron's own simpler 93588 flashlight. It makes the most sense for someone who wants one item to cover both a dim chart reading light and a small phone top up, rather than for anyone who specifically needs to power telescope electronics through an entire session.

Frequently asked questions