A Second Chance to See Comet Leonard

(Plain Text Version)

A New Comet: Good News or Bad News?

From the earliest ages, the appearance of a new comet was a source of excitement. Bright comets can be awesome to see, and they do not come frequently.

Sometimes, comets were considered a sign that something good was about to happen. More often, however, people feared that something terrible was coming soon.

Today, we know a lot more about comets. But just like the days of old, I have some apprehension when I hear that a major comet is coming. I don’t fear that earthquakes or crop failures will happen. I just wonder if I will be able to get a good look!

Astronomers can tell us where a comet will be, but not what it will look like. So, I get excited when I hear that a bright one is approaching. On the happy side, I look forward to seeing a beautiful and unique sight in the sky. On the downside, I foresee a struggle to see it at all.

Comet Leonard Comes to Town

Comet Leonard came from a region of our solar system called the Oort Cloud, which is about 1,000 times as far away as Pluto. Objects in the Oort cloud are beyond the reach of even our best telescopes.

After traveling for thousands of years, our new object was discovered in January 2021 by Gregory Leonard. It’s official name is C/2021 A1 (Leonard).

As it approached, it was visible in the Northern Hemisphere before sunrise. I’ll make no excuses: I wasn’t motivated to get out of bed to look for it. I waited until it moved into the evening sky.

Unfortunately, the comet was visible for only a short time after sunset and was very low in the sky. I made a couple of trips to the edge of the city but found the sky too hazy to see the comet.

A Happy Ending in the Southern Hemisphere

Thanks to the internet, I was able to remotely operate a telescope in Australia (see iTelescope.net). On my first try, I got a very good, sharp image. I enjoy looking at details of a good image, but I especially enjoy standing outside and looking at a comet “in person.”

Maybe I will set my alarm next time.

January 28, 2022 0

A “Near-Total” Lunar Eclipse

Here is a “clickable” link:

https://www.timeanddate.com/eclipse/lunar/2021-november-19

(Plain Text Version)

As our friend the Moon journeys around our planet it passes through our shadow on a regular basis. The Moon will be partially or completely covered, depending on the alignment of the Sun, Earth, and Moon.

Unlike a solar eclipse, it is not necessary to travel to see a Lunar eclipse. One needs only to be on the side of Earth facing the Moon. Bad news: if you are on the “wrong” side, or it is cloudy, you will miss it. Good news: Lunar eclipses are frequent, and another opportunity will come soon.

The Moon moves through our shadow in stages. At first, it darkens only a little bit, because Earth is not covering the Sun completely. Later, a much darker shadow appears as our planet completely covers the Sun.

To see the difference between the two types of shadows, take a ball or a disk of cardboard outside on a sunny day. Project the shadow of the Sun onto a sidewalk or some similar surface. Notice that the shadow is fuzzy at the edge. An ant in the fuzzy region would see that the Sun is partially covered. If the ant moves into to the dark portion of the shadow, it will see that the Sun is completely covered. The fully dark portion of the shadow is called the umbra, and the fuzzy portion is called the penumbra.

A total eclipse of the Moon occurs when the Moon is completely darkened by the umbra. Otherwise, it is a partial eclipse. Sometimes, the Moon enters the penumbra but not the umbra. One would have to look carefully to notice this type of eclipse, called a penumbral eclipse.

I have called this month’s event a “Near Total” eclipse, because only 97% of the disk of the Moon will be covered by the umbra.

Here is a link with an animation of the events of this eclipse, and other information:

https://www.timeanddate.com/eclipse/lunar/2021-november-19

For this eclipse, people in North America, South America, Australia, and Western Asia will have the best views.

No equipment at all is needed to enjoy this colorful display. While going about your other activities, you can go outside from time to time to see the progress. I can be a bit lazy, so I may simply set my alarm for the “Maximum Eclipse” time and look through a window.

Keep looking up!

November 6, 2021 0

Northern Lights – Not This Time…

For those who tried to see the predicted display of the Northern Lights, we hope you enjoyed the chance to go outside and take a look at the night sky.

I visited a semi-dark site near my home in Peoria, IL, but saw only stars and clouds.

We know that the Coronal Mass Ejection happened, but the bulk of it seems to have missed Earth. I received one report of a low, somewhat weak Auroral display in Northern Michigan (latitude 45 degrees North). See photo:

Aurora over Grand Traverse Bay, Michigan, night of October 30, 2021. Photo by Douglas Scobel

So, what will I do the next time an exciting prediction is made? I think you know.

Keep looking up, and you will see something!

John

October 31, 2021 0

Northern Lights Tonight?

Two days ago (10/28/21), the Sun released a large quantity of protons and electrons. This event is called a Coronal Mass Ejection (CME). This particular CME was stronger than usual, and is directed toward Earth. It is expected to reach Earth today (10/30/21).

CME’s can trigger vivid Aurora displays. This event is expected to strike our Northern Hemisphere, beginning with Europe and continuing to North America. Although Auroras are rare at Latitudes below 45 degrees, this event may be visible in places like Kansas, Illinois, and Virginia.

So, tonight would be a good time to look for the Northern Lights. It helps greatly to be away from city lights. Look to the North when the sky is fully dark.

Auroras are only moderately predictable, so we may not see anything…or we may see a huge display! Once in the 1970’s I was awakened in the middle of the night by my roommates to go outside and take a look. There were gray-white displays covering the entire sky. The city lights (in Ann Arbor, MI) couldn’t take anything away from the view.

Have a great night!

Here is a link with more information: https://www.accuweather.com/en/space-news/northern-lights-to-glow-over-us-halloween-aurora-borealis/1040379

October 30, 2021 0

Astronomy At The Beach Is Back!

Pardon me for not mentioning this sooner, but Astronomy At The Beach returns tomorrow!

Again, it will be an online event, with all-new presentations and online telescope views. Since we are online, we can visit the Southern Hemisphere: Maxi Falieres from Argentina will take us on a live a tour of the Southern Hemisphere skies! This will be from 10PM to Midnight EDT.

There are many events, so please see the link:

https://www.glaac.org/astronomy-at-the-beach-2021/

September 23, 2021 0

Three For One!

SPECIAL – THIS WEEK – THREE FOR ONE!

A lot of people would say that the Moon, Jupiter, and Saturn are the three most beautiful objects for small telescopes. For the next month, Jupiter and Saturn are well positioned over the southern horizon in the early evening. They are high enough to be free from disturbance by the atmosphere. For the next few days, the Moon will join them to make a celestial trio.

So, this is a great time to bring out the telescope and enjoy these three beauties.

Happy observing!

September 16, 2021 0

Meteor Outburst!

Here are two links with more information:

https://earthsky.org/astronomy-essentials/unexpected-perseid-outburst-wows-viewers/

https://spaceweatherarchive.com/2021/08/18/perseid-meteor-outburst-2/

(Plain Text Version)

The Perseid meteor shower has a reputation for being a reliable event. It reaches its peak on the night beginning August 12. Under a dark sky, roughly 60 meteors per hour can be expected. Unlike many other showers, it produces meteors a few nights before and after the peak night.

Although the Perseid shower is consistent in many ways, no meteor shower is fully predictable.

An Outburst on August 14, 2021

One day after the historical peak, an outburst was seen in the United States and Canada from 1:00-4:00 AM CDT. Approximately 120 meteors were observed per hour, about five times the usual number for this “off peak” date.

Scientists were not totally surprised by this outburst, because similar but smaller events occurred in 1993, 2018, 2019, and 2020.

Why Do Outbursts Occur?

Meteor showers are fed by streams of material which detach from comets as they orbit the Sun. These particles (called meteoroids) travel around the Sun with orbits similar to those of their parent comets. When Earth passes through one of these streams, the repeated streaks of a meteor shower are seen in the sky.

Comets don’t shed their particles in a uniform pattern, so the visible meteor count can vary from year to year, day to day, and even hour to hour.

How To Find an Outburst

One must be watching the sky at the right time! Usually, this time will be unknown. Since we all have busy schedules, it may not be practical take time to observe on nights other than the “peak” night.

To avoid an unproductive session, the sky can be scanned during periodic trips outside. It would help to watch for a few minutes, so that the eyes can gain at least some dark adaptation. (Full dark adaptation takes around 45 minutes.) For most locations, light pollution could hide many meteors. This technique is far from ideal, but it may reveal the unexpected!

September 5, 2021 0

Warming Up: the Mars Helicopter

https://mars.nasa.gov/technology/helicopter/

(Plain Text Version)

New Ways to Explore the Red Planet

Today, the standard method of exploring the surface of the Moon or a planet is to land a robotic crawler loaded with cameras and scientific instruments. In my review of space missions, I was surprised to learn that these vehicles were very rare before the 21st century.

A Bit of History

In the beginning of the Space Age, missions were quite simple by today’s standards. The first lunar missions used a rather obvious procedure: transmission of data before collision with the Moon.

The first few years of space exploration were plagued by all sorts of problems. For every success, there were several failures.

Here is a timeline of the milestones:

1957: Sputnik 1, the first artificial satellite was launched.

1959: Luna 2 returned data before lunar impact.

1966: Luna 9 made first soft landing on the Moon, and returned photos and radiation data.

1969: Astronauts aboard Apollo 11 landed on the Moon.

1970: First of two Lunokhod missions landed on the Moon, and deployed the first robotic crawler to operate away from Earth.

1997: The Mars Pathfinder crawler was deployed on Mars and functioned for more than two months.

2004: Two vehicles were deployed on Mars, and functioned for a long time: Spirit (6 years) and Opportunity (15 years).

In summary, 4 decades elapsed from Sputnik 1 before remote crawlers became commonplace.

2021: Will It Fly?

We are on the verge of another major step in exploring our neighboring bodies: within a few days, Ingenuity, the first Martian helicopter will be flight-tested.

For a successful flight, many challenges need to be overcome, such as generating enough lift in the ultra-thin Martian atmosphere, and controlling the craft with limited human interaction.

Ingenuity has tested its rotating blades at low speed, and is scheduled to fly on Sunday, April 11. For details, see:

https://mars.nasa.gov/technology/helicopter/

April 9, 2021 0

Thinking About the 2024 Solar Eclipse? This Book May Help You.

Book Review: Road Atlas for the Total Solar Eclipse of 2024

By Fred Espenak – Astropixels Publishing – 40 pages – $19.95 (Color Edition)

On Monday, April 8, 2024, those in North America will have the opportunity to experience a total solar eclipse. Having enjoyed the eclipse of 2017, I am starting to plan for our next opportunity.

The heart of this book is three overview maps and 26 detail maps of the path of totality in Mexico, the United States, and Canada. The base map is the familiar Google Maps rendition of the towns, major roads, major parks, and bodies of water. This base is overlaid with northern and southern limits of totality, the center line, and lines indicating duration of totality. For every 5-minute interval, the location of mid-eclipse is marked on the center line, with a notation of the duration of totality and the elevation of the Sun.

This is the basic information needed to begin to select a place to view the eclipse.

When I was planning for the August 2017 total eclipse, I didn’t buy the 2017 edition of this atlas. Since of the information in the atlas was available elsewhere, I didn’t see the need to buy the book. I learned (the hard way) that planning is more efficient when all the basic information is on the same sheet of paper.

The print clarity of the maps was a disappointment. The major roads are easy to identify, but the secondary roads are almost invisible, especially in the path of totality, which is shaded light gray. To get to a location, better maps or navigation software would be needed.

In 2017, I had a good look at the eclipsed Sun, and enjoyed watching peoples’ reactions to the whole experience. In 2024, I would like to watch the Moon’s shadow as it appears to move across the ground. My “dream location” would include a high point overlooking a valley. I will be able to do the initial screening for possible sites with Espenak’s atlas, combined with other resources.

I bought my 2024 atlas early, so I can combine site exploration with my other travels. My home is only a 3 ½ hour drive from Indianapolis, Indiana, which is near the center line. In the next four years, I hope to have a chance to visit some sites in this area. I would also like to identify some alternate locations further away; in case cloudy skies are predicted.

As eclipse day approaches, weather patterns may change suddenly, necessitating last-minute changes of plans. In this case, the eclipse road atlas could be worth its weight in gold.

This is a link to a vendor for this book, along with a lot of information about eclipses. An image of the book cover is included. This image includes a good sample of the detail maps.

November 24, 2019 0

Have You Ever Seen a Comet?

The night sky has many treasures in store for us. Most of these objects are very far away, and don’t appear to change much from year to year. Without precise measurements with telescopes, they seem to be stationary. Others, like the Moon and the planets, are close enough that their motion is obvious.

In addition to the Moon and the planets, comets show visible progress as they move across the sky. Comets are icy objects which orbit the Sun. Unlike planets, comets have elongated orbits which bring them close to the Sun, and then take them far away from the Sun. For example, Comet Halley comes closer to the Sun than the planet Mercury, and then travels out to the vicinity of Neptune and Pluto.

When a comet approaches the Sun, the ice begins to evaporate. The water vapor, combined with soil, moves away from the surface, and forms a visible tail. Energy from the sun can ionize (add or remove electrons from) the water vapor, and cause a second tail to develop.

This month, a comet has made a close (11.6 kilometer) approach to Earth and is now moving away from us. It is called 46P/ Wirtanen. It is high in the sky for observers in the Northern Hemisphere. This week, the Moon is brightening and coming closer to “46P” every night. This interferes with a good look at the comet. Beginning December 23, 2018, the sky will be dark before the Moon has a chance to rise. For the following two weeks, the Moon will not interfere. (As always, don’t miss an opportunity to see 46P, even when the Moon is out.)

181213 image1 cropped — I obtained this image of Comet Wirtanen using a remote rental telescope on December 13, 2018. This comet has a faint tail, which doesn’t appear in this image. (itelescope.net T14; Takahashi 106 mm refractor, 5-minute exposure)

Comet Wirtanen is not bright enough to be seen naked-eye (to my best knowledge). Many people are finding it with binoculars and small telescopes. I have had an excellent view with my 10” (254mm) reflecting telescope.

Here is a link to a finder chart.

https://www.skyandtelescope.com/astronomy-news/observing-news/comet-46p-wirtanen-and-moon/

I admit that finder charts can be difficult to use. In this instance, however, the bright star Capella is a very good reference point. An alternative to paper charts is the free version of the smartphone app “SkySafari”. Once it is installed, simply tap “Search”, then “Brightest Comets”, then “46P Wirtanen”, then “center”.

Here are more links about Comet Wirtanen:

https://earthsky.org/todays-image/photos-comet-46p-wirtanen-brightest-comet-2018

https://www.space.com/42756-comet-46p-wirtanen-original-rosetta-target.html

https://earthsky.org/space/46p-wirtanen-possibly-visible-to-eye-dec-2018

Keep looking up!

John

December 19, 2018 0