Please make a donation to support Gunter's Space Page.
Thank you very much for visiting Gunter's Space Page. I hope that this site is useful and informative for you.
If you appreciate the information provided on this site, please consider supporting my work by making a simple and secure donation via PayPal. Please help to run the website and keep everything free of charge. Thank you very much.


IMPRESS [University of Minnesota]

IMPRESS (Impulsive Phase Rapid Energetic Solar Spectrometer) is a solar science mission that will fly a hard X-ray (>10 keV) spectrometer on a 3U CubeSat to investigate particle acceleration in solar flares.

IMPRESS will perform soft and hard X-ray (SXR and HXR, respectively) spectroscopy of solar flares in the rising phase of Solar Cycle 25. IMPRESS is optimized to observe high-cadence HXR and SXR spectra from a wide range of solar flares (targeting C1 to X1 class flares) without saturating the detector and without the need for disruptive movable attenuators.

These measurements will be used to

  • investigate sub-second variations in HXR flux that strongly constrain flare acceleration timescales;
  • perform a mission of opportunity by co-observing HXRs from solar flares along with the Spectrometer/Telescope for Imaging X-rays (STIX) onboard Solar Orbiter, systematically studying directivity; and serve as a HXR monitor of flares associated with solar eruptive events that will drive space weather in the next solar cycle.

The IMPRESS detectors are four CeBr scintillator crystals read out by silicon photomultipliers and one Amptek X123 silicon drift diode. To capture fast time variations, these detectors will produce 4-12 keV SXR spectra at a 1 Hz cadence and 8-100 keV HXR spectra at a 32 Hz cadence. The payload is carried on a 3U CubeSat platform.

The data acquired by will be used to help understand how solar flares accelerate particles to extraordinarily high energies. Fast bursts undistinguishable to previous solar-dedicated HXR imagers (e.g. RHESSI) will be analyzed to understand their durations and distributions, placing key constraints on particle acceleration processes. Coordinated observations with STIX will systematically studying HXR directivity, providing a quantitative test of the thick-target model of solar flares. IMPRESS's detector system is being developed with the intention of its applicability to any system requiring fast high-energy (X-ray and gamma ray) spectroscopy with high time precision.

It was selected in 2020 by NASA's CubeSat Launch Initiative (CSLI) program by the CubeSat Launch Initiative (CSLI) to be launched as part of the ELaNa program. IMPRESS has a target launch date of late 2021 with a planned minimum mission life of at least 6 months.

Nation: USA
Type / Application: Science, solar
Operator: University of Minnesota
Contractors: University of Minnesota
Configuration: CubeSat (3U)
Propulsion: None
Power: Solar cells, batteries
Lifetime: 6 months
Satellite COSPAR Date LS Launch Vehicle Remarks
IMPRESS - 202x (via NASA ELaNa program) with ?


Cite this page: