This was one of the months that the news come from the sky, like very pleasant tetris bricks.
Three robots and a helicopter are roaming Mars as we speak. In addition to rovers Perseverance and Curiosity now there is Zhurong (named not after psychological traits but after a god of fire). Zhurong was carried there by Tianwen-1, the orbiter that arrived at martian orbit three months ago. Both these are sent by China’s National Space Administration and, if you like historical statistics, this makes China the third country to land on Mars and the first ever to land successfully on first attempt.
Zhurong’s main mission is to look for signs of liquid water in Mars’ past and it’s designed to last for 90 days.
However, this kind of designated age shouldn’t mean much. Ingenuity, the cute helicopter that arrived on Mars with NASA’s Perseverance and first flew a few weeks ago, has already surpassed its own.
Designed for five flights and thirty days of operations, Ingenuity has already performed six of those in more than a month. Its record altitude has been 10 meters and its longest flights have lasted for almost two minutes.
Its sixth flight was troubled by wild instability, but it still managed to fly and land safely. The source of the instability was found to be that one of the photos it was shooting was lost accidentally. This threw off its motion calculations – but at least it proved that it can survive such errors.
As for the Perseverance rover, it had to wait patiently during the month that was Ingenuity’s nominal lifespan. But after the helicopter left the family nest, Perseverance started its own slow trek around Mars, free now to look for signs of microbial life.
It seems that one mystery concerning the sun might have now been solved.
This is the “coronal heating problem”. The photosphere, which is the visible surface of the sun, has a temperature around six thousand degrees Celsius. However the corona, which -bad associations aside- is the “atmosphere” of the sun, lying well above its surface, has a temperature of a million degrees. And nobody knows why.
Nobody? Well, not entirely. A possible explanation was put on the table back in the ’40s – and now it seems at last that it might be correct.
The explanation involves the huge motions inside the sun’s material, which raise huge magnetic fields. But this electrically charged material doesn’t only create magnetic fields; its motion also disturbs them, and the result is the creation of waves that carry humungus amounts of energy.
This energy is supposed to travel along the path of “solar magnetic flux tubes”, rising from the surface until they reach the corona. There the waves burst and heat up everything .
These “Alfvén waves” (after the name of Hannes Alfvén who came up with them) have always been taken seriously but with no definite proofs for their existence. Well, guess what? There is now some good proof for their existence.
This came by virtue of the Dunn Solar Telescope at New Mexico, which has taken advantage of the latest and greatest in imaging spectroscopy: that is, analyzing the spectrum of incoming light to make detailed images of things. Apparently this permitted the waves to be seen, crossing out one item from humanity’s wish list for the sky.
Finally, the orbital telescope Chandra by NASA has revealed a new image of the centre of the Milky Way. And what an image it is.