On the 30th of January, Spitzer Space Telescope war retired from activity, after almost seventeen years. It had a beautiful and surprising journey. Initially, it was expected that its mission would last for two and a half years until the liquid helium was exhausted.
But Spitzer proved to be useful without it too. Although most of the instruments couldn’t function anymore without the liquid helium, Spitzer’s two shortest-wavelength modules of the IRAC camera continued to operate with the same sensitivity. This fifteen-years travel was called Spitzer Warm Mission.
Spitzer was launched on 25 August 2003 from Cape Canaveral. It cost US$720 million, but scientists consider it to have been worth every penny. Its second-to-last mission made Spitzer leave in full glory: Spitzer brought data on a rare nearby “late T” brown dwarf.
A brown dwarf is an object made of gas without enough mass to be called a star. Because of the absorption of sodium and potassium in the green part of the spectrum of T dwarfs, the appearance of T dwarfs to human visual perception is estimated to be not brown, but magenta.
NASA Said “Farewell” To The Spitzer Space Telescope
NASA posted in its farewell message to Spitzer: “But the second-to-last scientific observation made by this great observatory was a brown dwarf discovered by citizen scientists at the Backyard Worlds: Planet 9 citizen science project.”
Backyard Worlds: Planet 9 is a NASA-funded citizen science project which aims to discover new brown dwarfs and other low-mass stars, some of which might be among the nearest neighbors of the Solar System, and might conceivably detect Planet Nine.
Planet Nine is a hypothetical planet in the outer region of the Solar System. Its gravitational effects could explain the unusual clustering of orbits for a group of objects bodies beyond Neptune that orbit the Sun at distances averaging more than 250 times that of the Earth.
But “until Planet Nine is caught on camera it does not count as being real. All we have now is an echo,” said astronomer Konstantin Yurievich Batygin. Maybe the space probe following the Spitzer Space Telescope will catch it.