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Posts Tagged ‘Halley’s Comet’

05/04/2021 – Ephemeris – We cross Halley’s Comet debris this week

May 4, 2021 Comments off

This is Bob Moler with Ephemeris for Tuesday, May 4th. Today the Sun will be up for 14 hours and 23 minutes, setting at 8:51, and it will rise tomorrow at 6:26. The Moon, 1 day past last quarter, will rise at 4:20 tomorrow morning.

The Eta Aquariid meteor shower will reach their peak for us Thursday morning the 6th. The Eta Aquariids are caused by bits of Halley’s Comet, passing the Earth’s orbit heading out from the Sun. The Orionids of late October are debris of Halley’s comet passing the Earth’s orbit heading in toward the Sun. The Eta Aquariids are named for the star nearest the radiant of the meteor shower. The constellation of Aquarius has many shower radiants, which is why the shower is named for a star in Aquarius. The radiant rises shortly before 3:30am and astronomical twilight begins an hour later. There’s perhaps another half hour of visibility after that. The peak will occur Thursday morning where 20 meteors per hour or more might be seen.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

The sky dome for 4:30 am May 6, 2021. The Eta Aquariid radiant is near Jupiter. It looks like
two other minor meteor showers are active then with only a handful of meteors an hour
compared to the Eta Aquariids’ somewhat higher rates. The funny looking “n” character
next to Aquariid is the Greek letter Eta. Chart created using Stellarium.
Halley's meteor shower
We get two meteor showers from Halley’s Comet. The Orionids, when Halley is approaching
the inner solar system, and the Eta Aquariids when it’s leaving.
Credit my LookingUp program.

04/30/2020 – Ephemeris – See bits of Halley’s Comet in the morning crashing into the Earth’s atmosphere

April 30, 2020 Comments off

This is Bob Moler with Ephemeris for Thursday, April 30th. Today the Sun will be up for 14 hours and 13 minutes, setting at 8:47, and it will rise tomorrow at 6:32. The Moon, at first quarter today, will set at 3:47 tomorrow morning.

Do you remember seeing Halley’s Comet back in 1986? The actual pronunciation is “Hawley’s”, according to Sir Edmund’s contemporary Samuel Pepys. The reason I asked is whether you saw it in 1986 or are young enough to live long enough to see it in 41 years, we all have a twice yearly chance to see bits of Halley’s Comet, shed in previous returns through the inner solar system and strewn along its orbit, burn up in Earth’s atmosphere as the Eta Aquariid meteor shower going on now, or the Orionids in late October. The time to see the meteor shower is in the early morning after the Moon sets. That’s after 3:47 a.m. tomorrow morning and 4:22 Saturday morning. Astronomical twilight starts about 4:40 a.m. It will probably be 5 a.m. before it really interferes. With the meteors all over the sky, coming from the southeast.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Eta Aquarid radiant

The Eta Aquariid radiant at the peak of the shower. The radiant moves slowly to the east with time. Credit: my LookingUp program.

Halley's Comet Orbit and meteor showers

Halley’s Comet orbit with the orbits of the inner planets showing the points at which the debris from the comet intersect with the Earth’s orbit causing meteor showers. Diagram credit JPL Small-Body Database Browser with my annotations.

10/11/2019 – Ephemeris – Interstellar comet 2I/Borisov ejects the same gas like ordinary solar system comets

October 11, 2019 Comments off

Ephemeris for Friday, October 11th. Today the Sun will be up for 11 hours and 12 minutes, setting at 7:05, and it will rise tomorrow at 7:54. The Moon, 2 days before full, will set at 6:24 tomorrow morning.

The interstellar comet 2I/Borisov, which was discovered August 30th by the Crimean amateur astronomer Gennady Borisov has given its first clues of its makeup. With data collected from the William Herschel Telescope in the Canary Islands the comet was discovered to give off cyanogen, a cyanide gas. This is just like what is given off by comets that belong to the solar system. As the comet comes closer to the Sun and warms up further more and different gasses will be liberated. It was the discovery of cyanogen in Halley’s Comet back in 1910 caused a panic because on that pass the comet’s tail swept past the Earth. However a comet’s tail is so tenuous that no cyanogen was detected in the Earth’s atmosphere.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Color photograph of C/2019 Q4

Color photograph of 2I/Borisov. Image Credit: Gemini Observatory/NSF/AURA

Spectrum of 2I/Boresov

Spectrum of 2I/Borisov. Top covers part of the visible and ultraviolet spectrum. The bottom zooms in on the CN emission. Credit https://arxiv.org/abs/1909.12144

10/09/2019 – Received word that C2 has also been discovered. This is also normal and can color the coma green. (I recorded the program on 10/06 illustrated this post on 10/07 due to being away due to my daughter’s surgery.)

05/05/2015 – Ephemeris – Eta Aquariids, an early visit of Halley’s Comet

May 5, 2015 Comments off

Ephemeris for Tuesday, May 5th.  Today the Sun will be up for 14 hours and 24 minutes, setting at 8:52.   The Moon, 2 days past full, will rise at 10:29 this evening.  Tomorrow the Sun will rise at 6:26.

The Eta Aquariid meteor shower will reach peak tomorrow morning.  But the Moon will be bright, so only the brightest of them will be seen.  However if you’re waiting to see the return of Halley’s Comet, you needn’t wait until the main body of the comet returns in 2061.  Halley’s Comet has made many passes of the inner solar system in recorded history, and many more before that, returning to the inner solar system every 76 years or so, before returning to its frigid home beyond Neptune.  It’s closest to the Sun, called perihelion is inside Venus’ orbit.  On the way in and out it passes close to the Earth’s orbit.  It has left a trail of debris, which we pass through in May and again in October.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

Eta Aquarid radiant

The Eta Aquariid radiant at 5 a.m. The radiant moves slowly to the east with time. Credit:  My LookingUp program.

Halley's meteor shower

We get two meteor showers from Halley’s Comet. The Orionids, when Halley is approaching the inner solar system, and the Eta Aquariids when it’s leaving. Credit:  My LookingUp program.