Inspiring Tomorrows Astronauts: How Ham Radio Brings Space To Classrooms

India.com

7 hours ago

On July 4, Indian astronaut Shubhanshu Shukla spoke to students across the country using a ham radio from the International Space Station (ISS).
Here's a simple explanation of what ham radio is, how it works, and why Shukla used it for this special interaction.
What is a Ham Radio?
Ham radio, also called amateur radio, is a licensed way of using radio signals to talk to others without the need for mobile networks or the internet. People mostly use ham radio to learn more about how radio works, to explore communication as a hobby, or to connect with others across long distances. It also plays an important role during emergencies or disasters, where normal communication systems may not work, allowing people to send urgent help messages (SOS) and stay connected when needed the most.
Two licensed ham radio users can talk to each other using a specific radio frequency. To do this, they use special equipment like a transceiver (which can both send and receive signals) and an antenna. These trained operators know how to set up and use this equipment to stay in touch over short or long distances.
Ham radio communication can happen at different levels—it can be within the same area, across the world, or even with people in space. In India, anyone who is 12 years or older can use a ham radio. However, they must get a license first, which is given by the Ministry of Electronics and Information Technology.
Radio frequency refers to the range of electromagnetic waves used for wireless communication. These waves are part of the electromagnetic spectrum and are measured in units called hertz (Hz).
In simple words, radio frequency (RF) is the speed at which radio waves travel through the air to carry signals—like sound, voice, or data—between two points, such as a radio station and your radio, or a ham radio on Earth and one in space.
Different types of communication—like FM radio, TV, mobile phones, and ham radio—use different ranges (or bands) of radio frequencies to avoid interfering with each other.
Here's a explanation of the frequency ranges used by FM radio, TV, mobile phones, and ham radio:
FM Radio
Frequency Range: 88 to 108 megahertz (MHz)
Use: For playing music and talk shows on radio.
Example: Popular FM stations like 91.1 MHz or 98.3 MHz.
Television (TV)
Frequency Range (varies by country and type):
VHF TV channels: 54 to 216 MHz
UHF TV channels: 470 to 806 MHz
Use: Transmitting audio and video for TV channels.
Mobile Phones
Frequency Range:
2G/3G: Around 850 MHz to 2100 MHz
4G LTE: 700 MHz to 2600 MHz
5G: Can use anything from 600 MHz to 6 GHz and even above 24 GHz (called mmWave)
Use: Voice calls, mobile data, internet, video calls, etc.
Ham Radio (Amateur Radio)
Frequency Range: From 1.8 MHz to over 1,200 MHz (spread across many bands)
Use: Two-way voice communication, Morse code, digital data, and satellite communication. Some popular bands:
HF (High Frequency): 3–30 MHz (for long-distance)
VHF (Very High Frequency): 30–300 MHz (for local)
UHF (Ultra High Frequency): 300–1000 MHz (for clear short-range)
How do astronauts use ham radio during space missions?
Ham radio was first used in space in 1983, during a space shuttle mission, to allow communication between astronauts in space and people on Earth. Today, the International Space Station (ISS) also has its own ham radio system, called Amateur Radio on the International Space Station (ARISS). It is often used by astronauts to talk with students back on Earth. These live chats are meant to inspire and encourage young minds to learn more about space and science.
Amateur radio groups, together with space agencies from the United States, Russia, Canada, Japan, and Europe, help make these educational radio talks possible by giving the necessary equipment and technical support.
For safety reasons, the ARISS team turns off the ham radio on the International Space Station during important events like spacecraft docking. This is done to avoid any chance of the radio signals disturbing other critical systems.
In what way will the Axiom-4 astronauts use ham radio?
During the Axiom-4 mission, astronauts from India, Poland, and Hungary will use ham radio to connect with people in their home countries. They plan to do this twice during their 14-day stay on the International Space Station (ISS).
These radio contacts will happen when the ISS passes over a certain area on Earth and is visible for a short time. Each time this happens, they'll try to set up a ham radio connection. The best time for this communication usually lasts between five to eight minutes.
During Shukla's radio session, different frequency bands will be used to send and receive signals. These include a voice downlink at 145.80 megahertz, a voice uplink at 144.49 megahertz, and a very high-frequency (VHF) channel at 145.825 megahertz for sending and receiving data. The VHF channel is mainly meant for the South Asia and Pacific regions.
The Indian astronaut began the interaction at 3:47 p.m. First, a call was made to the United States through phone or internet, and then the ham radio connection with Shukla was successfully established.
Why is ham radio considered a backup communication tool?
Even though modern technology has made communication faster and more advanced, ham radio is still one of the most reliable ways to stay connected. It works well even when other systems fail, making it a useful backup method.
There have been many times when ham radio helped during emergencies, especially when phone lines or internet services stopped working because of war or natural disasters like earthquakes, cyclones, and floods.
In India, ham radio played an important role in providing emergency communication during major events such as the Bhuj earthquake in 2001, the Indian Ocean tsunami in 2004, and the Uttarakhand floods in 2013, among others.
(Girish Linganna is a Defence and Aerospace Analyst based out of Bengaluru. He is also Director of ADD Engineering Components, India, Pvt. Ltd, a subsidiary of ADD Engineering GmbH, Germany. The views expressed in this article are of the author only.)