BurstCube Mission: NASA Launches Shoebox-Sized Satellite to Study Mysterious Gamma Ray Bursts

On March 21, NASA sent a small satellite called BurstCube to the International Space Station aboard the 30th SpaceX Commercial Resupply Services mission. Once it arrives, it will be released into orbit to explore one of the most powerful and violent events in the known universe: gamma ray bursts (GRBs).

What are Gamma Ray Bursts?

Gamma ray bursts refer to short-lived explosions of the highest-energy light. These immensely energetic explosions can erupt with a quintillion times the luminosity of the Sun. They result from some of the most explosive events, like the collisions between neutron stars and the birth of black holes. These events lead to the creation of heavy elements like gold, and other ingredients for life like iodine.

These outbursts can last anywhere from a few seconds to as much as several hours, characterized by a very intense flash of gamma rays. Then it is followed by the emission of energy at longer wavelengths, including X-rays, ultraviolet light, or other forms of electromagnetic emissions with afterglow.

Gamma ray bursts were discovered by chance, yet they are proven invaluable for modern researchers. Studying their nature allows experts to gain valuable insight into different cosmic phenomena, such as gravitational waves and the death of very massive stars.

GRBs can be studied by using light or gravitational waves. Each technique reveals various characteristics about these powerful cosmic events in an approach known as multi-messenger astronomy.

Unveiling Cosmic Secrets

In 2017, both light and gravitational waves were detected from the same event during the observations of GW170817. At this moment, gravitational wave signal from the shell elliptical galaxy NGC 4993 was detected by LIGO and Virgo detectors as a pair of neutron stars merged.

The discovery marked a significant moment for astrophysicists with the first observation of gravitational waves confirmed by non-gravitational means. Since this event, astronomers have been eager to achieve similar discoveries.

According to research scientist Israel Martinez from the University of Maryland, humanity's current gamma-ray missions can only observe about 70% of the sky at any moment because their view is blocked by the Earth. This means that increasing the coverage with satellites like BurstCube can improve the odds of catching more bursts that coincide with gravitational wave detections.

The main instrument of BurstCube detects gamma rays with energies that range from 50,000 to one million electron volts. Its detectors are angels to enable scientists to detect and localize events over a wide area of the observable sky.

When a gamma ray enters one of the four detectors of the tiny satellite, it encounters a scintillator, a cesium iodide layer which converts it into visible light. The light then enters an array of 116 silicon photomultipliers which converts it into a pulse of electrons. This pulse is what BurstCube actually measures.

BurstCube belongs to a class of spacecraft known as CubeSats. These tiny satellites come in a variety of sizes based on a cube that measures 3.9 inches (10 centimeters) across. CubeSats do not only offer cost-effective access to space, but they also test new technologies to facilitate groundbreaking astronomical discoveries.