Skywatch for the week of April 19, 2021
Mon Apr 19, 2021 FIRST SPACE SHUTTLE LAUNCH
This month marks the fortieth anniversary of the first launch of the space shuttle. The shuttle was named Columbia, and it was piloted by astronauts Robert Crippen and John Young, the ninth man to walk on the moon. Shuttle liftoff was at Cape Canaveral on April 12, 1981 at 7 in the morning; they were in orbit for two days, returning to earth, this time at Edwards Air Force Base in California, on April 14 at 1:21 p.m., Eastern Standard Time. Columbia is gone now; in 2003, at the end of its 28th mission, the space shuttle broke apart on re-entry into the earth’s atmosphere and all seven astronauts on board perished. The space shuttle program ended in 2011, when after 135 missions, the last space shuttle to fly, Atlantis touched down to earth. It is currently on display at NASA’s Kennedy space center on Merritt Island here in Florida.
Apr 20, 1928 Astronomer Gerald Hawkins born
Tue Apr 20, 2021 LYRID METEOR SHOWER
The Lyrid meteor shower will reach peak activity over the next couple of nights. It’s coming out of the part of the sky where we find the constellation Lyra, the Harp, that’s why we call them the Lyrids. This is not a strong shower, but it does contain some bright fireballs, and the skies should be fairly dark, at least once the moon, just past its first quarter phase, sets around 2 o’clock tomorrow morning. Which is terrific, because most meteor showers are at their best between midnight and dawn! Get away from bright streetlights. Face east, and then look up toward the zenith. You don’t need a telescope to see these momentary bright streaks of light, in fact a telescope would hinder your view. Take a lounge chair to lean back in, dress warmly, and don't forget to protect against mosquitoes and other hazards. And if it’s cloudy or raining, go back inside, you can’t see meteor showers during rain showers.
Wed Apr 21, 2021 DEATH OF MARK TWAIN
Samuel Clemens, better known as Mark Twain, died on April 21st, 1910. Twain was born in 1835, the same year that Halley’s Comet made an appearance in the heavens. In 1909 he wrote, “I came in with Halley's Comet in 1835. It is coming again next year, and I expect to go out with it. It will be the greatest disappointment of my life if I don't go out with Halley's Comet.” The comet’s orbit brings it close to the sun every seventy-six years on average, and it was visible at the time of his birth in the fall of 1835; but wasn’t actually visible again to most folks until a week or so after his death in 1910. But there was a brighter comet in 1910, which could be seen in the daytime, in the months just before he died. Perhaps he was thinking of this comet when he wrote, “Death is the starlit strip between the companionship of yesterday and the reunion of tomorrow.”
Thu Apr 22, 2021 Thu Apr 22, 2021 NAME THAT PLANET
Let’s play “name that planet.” I’ll give you the names of some or all of the moons that orbit a particular planet, and you have to figure out which planet it is. For example, if I said, “luna” or “moon,” you would respond with “earth.” All right, let’s start. “Phobos” and “Deimos,” which mean “fear” and “panic?” These are the two sons, and also, the two moons, of Mars. Now try “Nix,” “Styx,” “Hydra,” “Kerberos,” and “Charon.” These are the five moons of Pluto. How about, “Juliet,” “Ariel,” “Umbriel,” “Titania,” “Puck,” and “Miranda?” Those are some of the moons of Uranus. “Adrastea,” “Metis,” “Amalthea,” “Callisto,” “Ganymede,” “Europa,” and “Io?” Those belong to Jupiter. Now try, “Rhea,” “Mimas,” “Enceladus,” “Atlas,” “Calypso,” “Dione,” “Pandora,” “Prometheus,” and “Titan?” That’s Saturn. Finally we have Nereid and Triton – that’s Neptune’s two largest moons. And two planets have no moons, which are they?
Fri Apr 23, 2021 HST ANNIVERSARY
On April 25th 1990, the Hubble Space Telescope was put into orbit. It had been carried up 400 miles above the earth’s surface by the space shuttle Discovery on April 24th, and about a month after release it began sending back images. There were problems with the telescope at first, mainly because its primary mirror was not quite the right shape. Still the Hubble worked about as well as the biggest telescopes on earth, and when corrective optics were put in place a couple of years later, it began outperforming all other telescopes. In the past few decades, Hubble has seen ammonia ice storms on Saturn, the impact of a comet on Jupiter, methane ice on Pluto, nearby red and brown dwarf stars, supernova explosions, open star clusters in the Magellanic clouds, globular star clusters in the Andromeda Galaxy, hot matter surrounding galactic black holes, and literally millions upon millions of far-out galaxies and quasars.