Jared May, What's up, The second Week of April 2021
Give Ohio a few weeks and the weather can pull a 180° on us. This week’s forecast has clouds scattered
about, but perhaps some clear moments in the week ahead. The nightly temperatures this
week do not drop below 50° which is great for stargazers because normally nighttime temperatures in
the early spring and late winter timeframe can get pretty cold. Sunset this week will be passing 8 PM so
the fainter stars won’t be showing until after 8:45 PM or so. During these potentially clear upcoming
nights be on the lookout for Comet C/2020 R4 (ATLAS), the last International Space Station flyover for
JGAP until at least April 17, an early-morning moon, and some news on an asteroid that was thought to
be on a collision course with earth.
There is another comet that may make some small news, designated Comet C/2020 R4 (ALTAS). Right
now this comet shines at a faint magnitude 9.6 and should be visible with 80mm binoculars or a small
telescope. This ice ball is located in a part of the sky that can only be seen late in the night (or very
early morning), specifically, its located in the constellation of Aquila and very close to the star Almizan.
C/2020 is pretty far away from the earth, about 72 million miles, but the closest approach is coming up
on April 23 when the comet will be 43 million miles from the earth. You also won’t want to miss this
comet because it won’t be around again for over 900 years!
The International Spaces Station (ISS) is a common sighting for regular stargazers who spend most of
their free nights under the stars (when it’s clear). The manmade satellite looks like a bright airplane
flying overhead but has no blinking lights, in fact, the light we see from the ISS comes from reflected
sunlight off its body and solar panels. For a seeable flyover to happen, the sun and the station’s orbit
have to be in just the right range of spots. This Wednesday look near the western horizon at 9:02 PM to
spot the station. It will pass overhead for 3 minutes heading to the south/southwest before crossing into
the shadow of the earth. This will be the last visible sighting of the ISS from Logan OH until after April 17.
The moon goes through its monthly cycle: new moon, waxing crescent, waxing gibbous, full moon,
waning gibbous, waning crescent, then back to new moon. This week the moon is passing through its
waxing crescent phase as it approaches new moon this weekend. No moon in the sky is ideal for looking
at smaller and fainter deep-sky objects. But if you find yourself waking up early and outside between
5:30 AM and 7 AM this Wednesday, peer over at the eastern horizon for a glimpse at the moon. A look
through binoculars may also reveal a neighboring Jupiter and Saturn to the crescent.
In 2004 an asteroid was discovered, 99942 Apophis, that was estimated to be 1,200 ft. across and was
given a 2.7% chance of impact with the earth on April 13 2029. This gave the asteroid a rating of 4 on
the Torino impact hazard scale meaning it would be capable of regional destruction on the order of a
several hundred megaton bomb (the largest nuclear weapon detonated was the Tsar Bomba rated at
just 50 megatons). Let me say the punchline for all of this – We are safe for at least the next 100 years
from this asteroid as per recent measurements on the object’s trajectory. These measurements were
made in March by NASA’s Goldstone Deep Space Communications Complex and the Green Bank
Observatory.
Get out and enjoy the warm and hopefully somewhat clear nights this week. There are rainstorms
forecast so it might be a little humid and get some condensation on your telescope or binocular
optics. This week try spotting the late-night comet, the ISS, the early-morning moon, or enjoy reading
about the close (but far enough) call.