Near Ultraviolet Transient Explorer (NUTEx): A CubeSat-Based NUV Imaging Payload for Transient Sky Surveys

TL;DR

NUTEx is a CubeSat-based near-ultraviolet imaging payload designed for transient sky surveys, capable of detecting short-lived astronomical events with high sensitivity in the 200-300 nm range.

Contribution

This paper introduces the design and capabilities of NUTEx, a novel CubeSat-based NUV telescope for transient sky monitoring, highlighting its unique optical and detector systems.

Findings

Wide field of view of 4 degrees

Sensitivity of 21 AB magnitude in 1200 seconds

Effective area of approximately 18 sq cm at 260 nm

Abstract

The Near Ultraviolet Transient Explorer (NUTEx) is a CubeSat-based near-ultraviolet (NUV) imaging payload designed for transient sky surveys and is currently under development. CubeSats are compact and cost-effective satellite platforms that have emerged as versatile tools for scientific exploration and technology demonstrations in space. NUTEx is an imaging telescope operating in the 200-300 nm wavelength range, intended for deployment on a micro-satellite bus. The optical system is based on a Ritchey Chretien (RC) telescope configuration, featuring a 146 mm primary mirror. The detector is a photon-counting microchannel plate (MCP) device with a solar-blind photocathode, paired with an in-house developed readout unit. The instrument has a wide field of view (FoV) of 4 deg, a peak effective area of approximately 18 sq cm at 260 nm, and can reach a sensitivity of 21 AB magnitude (SNR = 5) in a 1200 second exposure. The primary scientific objective of NUTEx is to monitor the night sky for transient phenomena, such as supernova remnants, flaring M-dwarf stars, and other short-timescale events. The payload is currently scheduled for launch in Q2 2026. This paper presents the NUTEx instrument design, outlines its scientific goals and capabilities, and provides an overview of the electronics and mechanical subsystems, including structural analysis.