The Earth’s atmosphere protects us from certain death, but it is also a shield that blind certain type of sensors. So the most important telescopes are orbiting the planet. NASA plans to launch a balloon the size of a football state that will go up into the stratosphere at the ASTHROS telescope, able to carry out measurements that have never been done before.
Hot air balloons may seem somewhat dated, but they are very helpful to NASA, which has been running its Scientific Balloon Program for more than 30 years. Every year it launches between 10 and 15 missions that use this type of transport.
The advantage of using balloons for certain types of missions, mainly to test instruments or take measurements, is that they are much cheaper and faster, when traveling to the upper layers of the atmosphere.
NASA is preparing a new mission that will break some records. Is designing a hot air balloon over 150 meters in diameter, which will go up to the stratosphere, 40 kilometers high, at the ASTHROS telescope. That is a height 4 times higher than that of airplanes.
Still the balloon will not go out into outer space. It will stay in the highest layers of the atmosphere, circling Antarctica three times, at the mercy of the winds, for almost a month.
The reason for this peculiar journey is that the 2.5-meter diameter ASTHROS telescope has been designed to measure infrared light coming from space. To avoid interference it must operate in the stratosphere at a temperature of 268 degrees below zero. Not even 40 kilometers high is it so cold, so it has a built-in cryo-freezer that works with solar panels.
From this privileged position, the ASTHROS telescope will be able to carry out measurements never carried out before, such as creating 3D maps with the movement and velocity of the gas around the newly formed stars, a data considered key to the birth of new planets.
It will also explore in detail the galaxy Messier 83 and the star W Hydrae, two peculiar formations that will help us understand how the universe was formed.
The launch of this giant balloon with the ASTHROS telescope is scheduled for 2023. And although the launch itself is simple, building the sensors and the telescope itself is a slow and expensive process.