The Dhaka Times Desk The last such incident happened in 1623. The scientist Galileo Galilei was still alive. That event happened 13 years after the invention of the telescope. Jupiter and Saturn are so close after 400 years!
As such, after 397 years, the world witnessed this rare event again. Last Monday, Jupiter and Saturn were closer than one tenth of a degree to each other. After exactly 60 years, that is, in 2080, these two planets will come so close again.
Scientists say that the two planets were in a straight line 800 years ago, but the last time they came this close was in 1623.
Vanderbilt University space researcher Professor David Weintraub said that such an event can be seen only once in a lifetime.
Scientists call it, 'Great Conjunction' or 'Mahasamilan' or 'Mahajugalbandi'. NASA has named this cosmic phenomenon 'Christmas Star 2020'.
Note that Jupiter, the largest planet in the solar system, orbits the Sun only once in about 12 years. Since Saturn is much farther from the Sun, its orbit is much larger than that of Jupiter. So Saturn takes about 29 and a half years to go around the Sun once. That is, when Saturn completes one orbit around the Sun, Jupiter orbits the Sun twice. That is why Jupiter moves past Saturn every 20 years.
Basically, we cannot perceive the distance or speed of planets and stars in the sky, we only see their position at different times. So from Earth we see Jupiter and Saturn coming very close, passing it and going away. But how close Jupiter and Saturn come depends on the position of the Earth. According to that position, when Jupiter transits Saturn on December 21 this year, the distance between the two planets from Earth is minimal. So their brightness is also the highest.
Things to do to prevent Corona virus
# stay at home all the time.
# Follow the rules and use mask when going out for emergency.
# three-layer surgical mask can be washed if desired.
# wash clothes after coming home from outside. Or hang it without shaking for at least four hours.
# Wash hands thoroughly (for at least 20 seconds) with soap or liquid before coming outside.
# plastic PPE or eyes, mouth, head after single use
Of course it can be washed thoroughly with detergent and dried.
# Wear PPE made of cloth or clean as described.
# Use a head cap that completely covers the hair.
# Those who have sneeze cough should follow all the rules promulgated by the government. Also, wash hands as directed before and after handling food items, keys, switches, mice, remote controls, mobiles, watches, computer desks, TVs, etc. and after using the bathroom. Those who have dry hands use Moisture after washing their hands. Soap or hand liquid can be used. Why can this virus remain in the crackle (cracked part) of dry hands? Avoid using highly alkaline soaps or detergents.
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