2020

The Great Conjunction of 2020

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On December 21, 2020 Jupiter and Saturn will appear closer in our sky than they have since the year 1623 — only .10º apart. By way of comparison, Earth’s Moon covers about .50º on average! In fact, the two planets will have so little visual separation that they may appear as one bright “star” in our evening sky. As with many objects we see in our night sky, planets Jupiter and Saturn will only appear to be near to each other; they will will be physically separated by about 456 million miles.

The position of the planets as they will be at 7:00 PM EST, December 21, 2020. The bright green line represents the sight line from Earth to Jupiter and Saturn. Image Credit: SkySafari / James Guilford

Here’s why the planets will appear so close in our sky:

Viewed from Earth and looking out toward Jupiter and Saturn we see the planets as if they were in the same orbit — like watching runners in their separate lanes as one overtakes the other. Viewed from “above” we can see that the planets remain well apart.

Viewed closer to the orbital plane of the planets we see how Jupiter and Saturn appear closer together against the background of space. The green line represents the sight line from Earth to the planets. Image Credit: SkySafari / James Guilford

As we drop lower and closer to the orbital plane it becomes more difficult to separate Jupiter and Saturn until, on December 21, 2020, we won’t be able to see them as discrete objects without the use of a telescope!

Jupiter and Saturn appear to merge, on December 21, 2020 as viewed from Earth and depicted here just above the orbital plane of the planets. Image Credit: SkySafari / James Guilford

While the previous extremely close conjunction took place in 1623, Jupiter and Saturn were too close to the Sun to be observed. The last time they could actually be seen so close together was even longer ago: on March 4, 1226. Great Conjunctions take place just short of 20 years apart and most are not so close as this year’s — the next will take place on October 31, 2040, when Jupiter and Saturn will be separated by 1.1º which will be close, but not so amazing as 2020.

Jupiter and Saturn may be seen in the same narrow field of view during 2020’s Great Conjunction. This simulation depicts the position of Jupiter’s Galilean Moons and Saturn’s giant satellite, Titan. Image Credit: SkySafari

If you plan to take a look, you’ll need clear skies (of course!) and you’ll need to be timely — the planetary pair will become visible low in the southwestern sky with the fading twilight and will set in the west by 7:20 PM, December 21. To see the individual planets during their close encounter will require a telescope — a small one will do — or a decent telephoto lens on a camera mounted on a tripod. Given good optics and clear skies, viewers will be able to make out the Galilean Moons of Jupiter and, perhaps spy Titan, Saturn’s brightest moon.

Before and after the 21st, Jupiter and Saturn will appear close together as they first approach, and then recede from the conjunction, continuing to move along their orbital paths. The historic astronomical event will be one night and one night only in our lifetimes. Clear skies, please!

Hey! That’s my fireball!

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Fireball image captured at 11:36 PM EDT, August 11, 2020 by Hiram’s NASA All-Sky Fireball Network camera. The time stamp in the camera image reads 03:36 UTC — Coordinated Universal Time — which converts to 11:36 PM EDT. Credit: NASA

 

by James Guilford

Hey! That’s my fireball!!

I had stepped outdoors to check the sky (hoping to see at least one Perseid Meteor) and witnessed a fireball  at 11:36 PM; it was captured by the NASA All-Sky Fireball Network camera system hosted by Hiram College. That was the first time I had spotted a meteor that was also captured by the automated camera. The “shooting star” is not very impressive in the picture but it was a beauty by eye, glowing brightly and leaving a long “smoke trail” as it traveled from south to north.

Below is a summary of the data the NASA system was able to derive from Hiram, Oberlin College, and Allegheny Observatory imagery. Rather than a Perseids meteor, it was classified as an Alpha Capricornids meteor — that shower peaked in late July.

Data Summary for the fireball recorded at 11:36 PM EDT, August 11, 2020. Credit: NASA

 

If you are interested in NASA’s All-Sky Fireball Network, here’s a link to their website. Meteor data are updated daily with image captures and event summaries. Hiram’s is one of 17 all-sky cameras located in the continental U.S. https://fireballs.ndc.nasa.gov.

On August 13, 2013, Hiram College became the host for one of NASA’s All-Sky Camera Fireball Network stations, Oberlin College and Allegheny Observatory joining with us. The automated camera system watches the sky every night for exceptionally-bright meteors called fireballs.

James Guilford operates Stephens Memorial Observatory for the Physics Department of Hiram College.

 

Perseids 2020: Dependable shower, dubious weather

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A fireball meteor streaks across the sky north of Hiram at 3:38 AM, August 8, 2020. The large white “blob” in this image is the waning Gibbous Moon. Credit: NASA All-Sky Fireball Network/Hiram College Camera

It’s Perseids season!

The annual Perseid Meteor Shower peaks from August 11 to 13, the event many consider to be the best meteor shower of the year, thanks to frequent meteors streaking across the sky and comfortable nighttime temperatures. This year, skywatchers can expect to see between 50 and 75 meteors an hour under dark skies, or about one meteor every minute. The meteors are bits of material strewn across Earth’s path in space by Comet 109P/Swift-Tuttle. The bits of dust and grit glow brightly as they burn up while entering Earth’s atmosphere at about 37 miles per second.

This year, for those who venture out before midnight on the peak date(s), Earth’s Moon won’t interfere. Dedicated meteor spotters — those who observe in the wee hours between midnight and dawn — may curse as Moon rises and brightens the sky, making faint meteors harder to see. There is another problem, however, much closer to home: the weather.

 

2020 Perseids Viewing Forecast for the continental United States. Credit: Accuweather

 

The weather forecast calls for mostly cloudy skies Tuesday and Wednesday nights. Of course.

Do not abandon hope.

The nights preceding and following the shower’s peak see occasional meteors from the Perseid and Alpha Capricornid showers and include fireballs (very bright meteors) from both. When the sky’s clear, go out and enjoy the mild nights that may include “shooting stars.” After twilight fades, find a dark spot, spread out a blanket, or untangle that deck lounge chair, apply a little mosquito repellent and look up. As your eyes grow used to the dark you’ll see more and more stars, planets Jupiter and Saturn gracing the southern sky, and with decently dark sky, spy the soft clouds of our own Milky Way galaxy. You’ll probably see a satellite or two, too.

 

Our Night Sky: August 11, 2020, 11:59 PM. Note: The bright dot that appears to be labeled Pluto is actually Jupiter! Pluto is the tiny purple speck next to it and you won’t be able to see Pluto. Credit: SkySafari — CLICK FOR FULL-SIZE IMAGE

 

Subtle lunar eclipse July 4 – 5

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Penumbral Lunar Eclipse. NASA Solar and Earth images, illustration by James Guilford.
A penumbral lunar eclipse occurs when the Moon passes through the thin outer shadow — penumbra — Earth casts out into space.

We’re fortunate that the night of July 4 is expected to be clear, and not just for the traditional booms and flashes of celebratory fireworks. Our Moon is getting in on the act, albeit with a much more subtle display in the form of a penumbral eclipse. The eclipse will take place from 11:07 PM to 1:52 AM EDT with maximum eclipse at 12:31 AM July 5.

We say subtle because, unlike a total lunar eclipse, Earth’s Moon will not change to reddish/coppery colors. The Moon will instead become oddly shadowed for a Full Moon, as it enters the outer fringes of Earth’s shadow in space — the penumbra. Only the “top” portion of Luna will pass through the penumbra making this eclipse especially slight. Still, it’s worth a look and it won’t be at a particularly late hour. A deeper penumbral lunar eclipse will take place the night of November 30, 2020.

Illustration of Earth's Umbra and Penumbra with Moon Positioned for Penumbral Eclipse.
Earth’s shadow streams into space away from the Sun. The shadow has a partially-shaded outer portion, and a deep inner cone. Moon is eclipsed when it enters Earth’s shadow. Moon is eclipsed when it passes through Earth’s shadow. Credit: SkySafari / J. Guilford

While it’s possible to view this eclipse with the unaided eye, binoculars will provide an enhanced view as would a small telescope.

Penumbral Shadow on Earth’s Moon at Maximum Eclipse. July 5, 2020 at 12:31 AM EDT. Simulation via SkySafari.

And just in case there’s any confusion, lunar eclipses are perfectly safe to view and photograph — it’s moonlight — so nothing to worry about there.

If you shoot any photos or have impressions to share with us, you can do so via our Twitter — @StephensObs

Penumbral Lunar Eclipse of July 4 – 5, 2020. Credit: NASA

NASA Eclipse Page available here: Penumbral Lunar Eclipse of July 4 – 5, 2020.

Season opening postponed

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Well, it looks like we’ll not be opening our Public Nights season this month after all.

Outside of the usual concerns over wet and cloudy weather, and issues with our old building, now we have public health matters to take into consideration.

While the observatory is pretty much open to outside air when in use, people are quite close together under the dome — closer than public health experts recommend.

We’d rather everyone enjoy the night sky in good health and not have Stephens become a place where illness is spread; so we will watch and wait for resolution of the pandemic COVID-19 disease. When gatherings again make sense, we’ll announce and commence our season of Public Nights.

Until then, we’ll point out opportunities for home stargazing when clear nights occur and most of those suggestions come via our Twitter feed. You don’t need to have a Twitter account to see what’s going on, simple visit:  https://twitter.com/StephensObs

Through this all, we’ll fall back on the wisdom of The Hitchhiker’s Guide to the Galaxy upon which is written in large, friendly letters, “Don’t Panic”. No need to hoard toilet paper or bottled water. Just be smart about what you do to protect your health and the well-being of others. There’s plenty of good information available online if you choose wisely.

Here are a few good resources:

Ohio Department of Health

Ars Technica — Updated Daily

World Health Organization