jump to navigation

Meteor Shower Season 2019 August 1, 2019

Posted by aquillam in Astronomy.
add a comment

Late July & Early August is full of meteor showers!

Two different showers originate in Aquarius. They tend to be low activity, but the July 30/August 1 new moon give you a better chance than usual of seeing something good!

Of course the most famous shower of the year is the Peseids. This year they peak around August 13, just in time for the full Moon. Fortunately, this very active shower not only has a high number of meteors at its peak, it has a really long period of activity before its peak.

There are also a couple other minor meteor showers, and you might catch one of two of those in the wee hours. Check out the AMS Meteor Activity Outlook for this week (July 27 – August 2) for more details.

It’s best to observe in the early morning hours. Meteors happen when the Earth runs into debris floating in space. In the early morning, you (the observer) are facing the same direction that Earth is traveling through space, so you’ll see more of the debris hitting the Earth. Also, at the beginning of August, the Moon will set early, and darker skies are important!

In the first week of August, you might spot 10 – 20 meteors per hour. Look eastward until about 3 AM, then turn southward until sunrise.

Here’s a map of the eastern sky at 1 AM on August 1st. Perseus is on the left (NE), Aquarius on the right (SE).

Looking east from Ann Arbor at 1AM August 1st.

Looking east from Ann Arbor at 1AM August 1st.

Advertisements

Don’t miss the Geminids! December 5, 2018

Posted by aquillam in Astronomy, MichiganAstro.
add a comment

One of the best meteor showers of the year takes up most of the month of December, but will be best on the mornings of December 13 & 14.

Rising ENE a little after 7 PM, the radiant of the Geminids is up nearly all night. As always, the best time to watch for meteors is in the hours between midnight and dawn, since that’s when your sky is facing the direction Earth is traveling, so heres a map for December 14 at 2 AM.

14Dec0205_z

The sky from 42º latitude at 2 AM on December 14, 2018. Note Orion toward the SW, and the Big Dipper in the NW. Click for bigger image.

Conveniently, the Moon sets at about 10 PM the evening before, so if you can get away from city lights, you’ll have good dark skies for the best observing time. This is an active shower though, so it’s work going out and looking anytime you happen to be up and the weather is clear.

According to the AMS, the Geminids have a peak rate of about 120 meteors per hour (or about 2 per minute), tying them with January’s Quadrantids for highest rate. The usually lousy weather of December makes them much less famous, and harder to watch, than the August Perseids.

Additionally, Earth&Sky points out this shower has a high number of earth-grazers – meteors that come in at a low angle and appear slow moving. They’re actually moving pretty fast – they’re coming up from behind and hitting the Earth, like a stone hitting your back  or side car windows while you’re driving down the road. They’re rare, but memorable, and only visible in the evening.

So get out and look for Gemini as often as you can from now ’till Christmas!

A naked-eye comet for the holidays (2018) December 4, 2018

Posted by aquillam in Astronomy.
add a comment

I guess I must be having a lot of fun, because it sure doesn’t feel like four months has passed since I last logged in here. But there’s a naked-eye comet out there, so I couldn’t let it go by without saying anything!

Comet 46P/Wirtanen is no Hale-Bopp or Hayakutake, but it’s a lot brighter than anything we’ve seen in the northern hemisphere for quite a while. It’s current observed magnitude comes in at a 5.4, making it about the same brightness as M13, the great cluster in Hercules. Experienced observers know this means it is visible to the naked eye, but only just, and only under ideal conditions when you know exactly where to look.

The good news is, it’s expected to get brighter. It’s also positioned perfectly for evening viewing in the northern hemisphere, and a pair of binoculars is all you need for a great view.

Many things affect how bright a comet appears, so predicting it can be a bit tricky. It should be brightest on December 16, but it’ll also be right next to the Moon that night, so looking a few days before or after is a good idea. Here’s a chart for 9 PM on December 16, with the position of the comet on several other dates noted.

Dec2018Comet

The sky on December 16, 2018. The yellow dots indicate the positions of comet 46P/Wirtanen at 9 PM on several other evenings between December 4 (under the arrow pointing to Deneb Kaitos) through December 31.

On December 4 – 5, it’s right next to Deneb Kaitos, one of the brightest stars in Cetus. It’ll pass less than 5º from Uranus between the 22 & 23. On the 29th, it’ll pass Hamal, the brightest star in Aries.

If you’d like regular updates, or charts for your location, check out the comet 46P/Wirtanen page on LiveSky.

Venus in August 2018 August 1, 2018

Posted by aquillam in Astronomy, MichiganAstro, Urban Observing.
Tags: , , , ,
add a comment

Everyone else may be talking about Mars, but don’t miss your chance to check out Venus this month!

 

The orbits of Earth, Venus, and Mercury about the Sun, with 16º elongation and maximum eastern and western elongation shown.
The maximum elongations for Venus are shown with the dashed lines, and those for Mercury are shown with the dotted lines.

Venus orbits closer to the Sun than we do. That means from our point of view, it never gets very far from the Sun. When it is farthest in the sky from the Sun, we call it greatest elongation. On August 18, Venus will be at greatest eastern elongation, and it’ll be a little over 45º east of the Sun. That means it’ll be easy to see in the western sky for at least an hour after sunset.

 

 

Additionally, Venus will be headed for a crescent phase, which brings it closer to us, so it’ll be getting bigger and brighter. It’ll actually be at it’s brightest near the end of September.

 

 

Because of the angle of the ecliptic, it sets a lot sooner in September. Here are a couple maps showing the ecliptic from SE Michigan (or anywhere between 40 – 50º N latitude) on August 1st and 30th, both 1 hour after sunset. You can see the ecliptic moves southward, which means anything on the ecliptic will set earlier in the northern hemisphere.

W (west) is at the center bottom and NW near the bottom right corner. The ecliptic runs from the top left corner to the bottom about 1/4 of the way between W and NW.

Venus and the ecliptic on August 1st 2018, 1 hour after sunset.

W (west) is at the center bottom and NW near the bottom right corner. The ecliptic runs from the top left corner to the bottom just to the left of W.

Venus and the ecliptic on August 30th 2018, 1 hour after sunset.

So now’s the time for the easiest and latest observations of Venus, and September will be the time for the brightest and most interesting telescopic view of Venus!