Starberry-Sense: A low-cost Star Sensor

Subject : Science and technology

Section: Space Technology

Concept :

Researchers at the Indian Institute of Astrophysics (IIA) have developed a low-cost star sensor for astronomy and small CubeSat class satellite missions.

Star Sensor

Any satellite needs to know where it is pointed in space, and the instrument used for this purpose is called a star sensor.
The position of stars in the sky is fixed relative to each other and can be used as a stable reference frame to calculate the orientation of a satellite in orbit.
This is done by correctly identifying the stars in the sky towards which the star sensor is pointed.
The star sensor is essentially a celestial compass.

High cost of Star Sensors

In recent years CubeSats and small satellite missions have gained huge popularity. These missions utilize commercially available components for their design and development, but the typical cost of a commercially available star sensor often exceeds the total budget for a CubeSat.

Starberry-Sense

Based on commercial/off-the-shelf components, this star sensor costs less than 10% of those available in the market.
It is made from a single-board Linux computer called Raspberry Pi, which is widely used among electronics hobby enthusiasts.
The star sensor has successfully undergone the vibration and thermal vacuum test that qualifies it for a space launch and operations.
These tests were conducted in-house at the environmental test facility located at the CREST Campus of IIA in Hosakote.

Applications

Starberry-Sense can help small CubeSat class satellite missions find their orientation in space.
Its modular design allows for quick and easy customization for various requirements.
For e.g., even though StarBerry-Sense is meant for space-based applications, a modified version will be interfaced with the Major Atmospheric Cherenkov Experiment (MACE), located at the Indian Astronomical Observatory (IAO), Hanle, Ladakh.
The Starberry-Sense is ready for launch on the PS4-Orbital Platform by ISRO and can be used for CubeSats and other small satellite missions in the future.

CubeSats

CubeSats are a class of research spacecraft called nanosatellites.
CubeSats are built to standard dimensions (Units or “U”) of 10 cm x 10 cm x 10 cm.
They can be 1U, 2U, 3U, or 6U in size, and typically weigh less than 1.33 kg per U.
These are employed for the In-Orbit Demonstration (IOD) of miniaturised technologies and for small payload-driven missions.
CubeSats reduce launch costs in two fundamental ways.
They don’t weigh that much, which means a rocket doesn’t need a lot of fuel to heft them.
In most cases, they also share a rocket with a larger satellite, making it possible to get to space on the coattails of the heavier payload.
There are some design challenges with cubesats.
However,the electronics are smaller and are therefore more sensitive to radiation. Their low cost also means they are generally designed to last for a shorter duration of time.