Perseverance rover sends back sounds of lasers from Mars
NASA has released the sound of lasers recorded by the Perseverance rover on Mars. The audio clips recorded by the microphone attached to the SuperCam mounted on the rover landed on the Red Planet on 18 February.
In contrast to the ‘pew pew’ sound effect we hear in Sci-fi movies, lasers in space produce sound similar to ‘continuous clicking’.
This is the first acoustic recording of laser impacts on a rock target on Mars from 2 March. The recording captures sounds of 30 impacts, some slightly louder than others. These sounds are of the lasers hitting Martian rocks.
Variations in the intensity of the zapping sounds will provide information on the physical structure of the targets, such as its relative hardness or the presence of weathering coatings.
Last week, NASA had also released the sound recordings of wind blowing on the Martian surface. Read more here
Most distant and ancient source of radio emission discovered
Scientists have discovered the most distant and ancient source of radio emissions known to date. The source is a quasar with powerful jets emitting at radio wavelengths. It is so far away its light has taken 13 billion years to reach us.
Quasars are very bright objects that lie at the centre of some galaxies. They are powered by supermassive black holes. As the black hole consumes the surrounding gas, energy is released, allowing astronomers to spot them even when they are very far away.
The newly discovered quasar, nicknamed P172+18, is so distant that light from it has travelled for about 13 billion years to reach us — we see it as it was when the universe was just around 780 million years old.
While more distant quasars have been discovered, this is the first time astronomers have been able to identify the telltale signatures of radio jets in a quasar this early on in the history of the universe. Only about 10% of quasars — which astronomers classify as “radio-loud” — have jets, which shine brightly at radio frequencies.
P172+18 is powered by a black hole about 300 million times more massive than our Sun that is consuming gas at a stunning rate. Read more here
Moon has an invisible sodium tail, researchers find
Researchers have discovered that the Moon has a tail made of millions of sodium atoms that get blasted out of the lunar soil and into the knownspace by meteor strikes. These particles are then pushed hundreds of thousands of miles downstream by solar radiation.
Every month, there are days when the moon sits between the Earth and the Sun. During this time, the Earth’s gravity drags the sodium tail into a long beam that wraps around the atmosphere before blasting into space on the opposite side.
The lunar tail is harmless and invisible to the naked eye.
However, during new moon days each month, the beam becomes visible to high-powered telescopes that can detect the faint orange glow of sodium in the sky. Read more about this here
Summers may last upto 6 months in Northern Hemisphere by 2100
A new study predicts that without efforts to mitigate climate change, summers spanning nearly six months may become the new normal by 2100 in the Northern Hemisphere.
In the 1950s in the Northern Hemisphere, the four seasons — summer, autumn, winter and spring — arrived in a predictable and fairly even pattern.
However, climate change is now driving dramatic and irregular changes to the length and start dates of the seasons, which may become more extreme in the future under a business-as-usual climate scenario.
The researchers used historical daily climate data from 1952 to 2011 to measure changes in the four seasons’ length and onset in the Northern Hemisphere. They defined the start of summer as the onset of temperatures in the hottest 25 per cent during that time period, while winter began with temperatures in the coldest 25 per cent.
The study found that, on average, summer grew from 78 to 95 days between 1952 to 2011, while winter shrank from 76 to 73 days. Spring and autumn also contracted from 124 to 115 days, and 87 to 82 days, respectively.
Accordingly, spring and summer began earlier, while autumn and winter started later.
Such changes can wreak havoc on agriculture, especially when false springs or late snow storms damage budding plants. With longer growing seasons, humans will breathe in more allergy-causing pollen, and disease-carrying mosquitoes can expand their range northward. Read more here
Scientists succeed in measuring the smallest gravitational force
Researchers have successfully measured the smallest gravitational force, opening up new possibilities for testing the laws of gravity on previously unattained small scales.
The team from Vienna succeeded in measuring the gravitational field of a gold sphere, just 2 mm in diameter, using a highly sensitive pendulum.
Gravity is the weakest of all known forces in nature. Larger objects are associated with stronger gravity, which is why, during the time of Isaac Newton, it was believed that gravity was reserved for astronomical objects such as planets.
It was not known until the work of English scientist Henry Cavendish that it was possible to show that all objects generate their own gravitational force. Using an elegant pendulum device, Cavendish succeeded in measuring the gravitational force generated by a lead ball 30 cm tall and weighing 160 kg in 1797.
In the latest work, researchers from University of Vienna built a miniature version of the Cavendish experiment. They used lasers to make precise measurements of the movements. This made it possible to determine the gravitational field of an object that has roughly the mass of a ladybug for the first time. Read more about this here