2020 vision

Welcome to 2020, the last year of the second decade of the 21st century.

The first decade of the 1st century consisted of the years 1 to 10, and the first century was the years 1 to 100, and the first millennium was 1 to 1000.  These decimal bundles of time begin with years ending in 1, so they must end with years ending in 0.

Still, you can call 2020 the first year of the twenty-twenties.

I’d be more than happy if my vision miraculously got back some way toward 20/20 (which means being able to see at 20 feet what you should be able to, whereas if it’s 20/50 you’re seeing at 20 feet what you should be able to see at 50).  I do expect the year to bring me some improvements.  As for our planet…

Here’s preliminary explanation about the spectacle that fairly regularly opens our years, coming on January 3: the annual shower of meteors called the Quadrantids.

See the end note about enlarging illustrations.

This space view is from 6 astronomical units (Sun-Earth distances) away from the Sun and 20° north of the ecliptic plane.  Earth is exaggerated 500 times in size, Sun only 5.  The straight blue line with the ram-horns symbol shows the vernal equinox direction (where the Sun appears at the March equinox).

The meteor stream is represented by the orbits of five of the particles of dust or rock composing it.  One follows the orbit given for the Quadrantids; for the others I’ve slightly changed the orbital element called the longitude of perihelion, suggesting how they could have set out in slightly different directions, relative to the hurtling comet, as they separated from its surface.  They are most likely to have separated near the time of perihelion – nearest to the Sun – when the comet’s ices were most warmed.  But the billions of other particles could have separated at other times and in other directions, so the stream really occupies a far vaster tube of space.  What we experience is just a sampling of the part of the stream that relatively tiny Earth passes through, not necessarily the central or densest part.

The two arrowheads showing the direction of the stream are at 30 days before and after its perihelion.  The perihelion of this stream is pretty close to Earth’s orbit.

Enough of the Quadrantids for just now.  Look out for another post nearer the time, showing how they will appear in your sky.

As for planet Terra, its dominating species is going to behave better of risk extinction.  “11,000 scientists just announced that climate change has us on track for ‘untold suffering’, while the UN says the collapse of our ecosystems could wipe out a million species.”  That was yesterday’s message fromthe crusading group Avaaz – I don’t know whether this link to an email will work.

Individuals should do what little they can, such as driving less and eating less meat.  Countries can do more, and here is something hopeful.

Half of the United Kingdom’s farmland should revert to nature.  So urges Sir Ian Boyd, who was a top government science adviser and an official in the Department for Environment, Food and Rural Affairs.  That 50% is upland and pasture, used for grazing livestock, and produces only 20% of the country’s food.  It would produce much more of value if farmers were paid for environmental stewardship and it reverted to woodland – storing greenhouse gas instead of generating it – also improving health, recreation, and happiness.  Boyd became vegetarian during his time at the department.  The 20% of food lost could be made up by vertical farming.  “I know there are big companies looking at how to really scale this up.”

Vertical farming – I’ve sung its praises before.  And here is more about it  And now I’ve learned of a charming small version of it: bee-friendly patches on the roofs of bus shelters in Utrecht.

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ILLUSTRATIONS in these posts are made with precision but have to be inserted in another format.  You may be able to enlarge them on your monitor.  One way: right-click, and choose “View image”, then enlarge.  Or choose “Copy image”, then put it on your desktop, then open it.  On an iPad or phone, use the finger gesture that enlarges (spreading with two fingers, or tapping and dragging with three fingers).  Other methods have been suggested, such as dragging the image to the desktop and opening it in other ways.

This weblog maintains its right to be about astronomy or anything under the sun.