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My Favorite Things, Vol 1.4 – Online Class and Asteroids

[I’ll continue from my previous post next month since the stuff here is time sensitive.]

Robert Armstrong
I first met him as I started to become involved w/ the SJAA board. I quickly learned that there was wisdom in every thought and opinion he shared. When he spoke, everyone listened. His long standing support for the SJAA, his wisdom, and everything embodied by his presence will be missed.

Online Astronomy Class
Someone I work with referred me to All classes are free and if you take a class while it’s offered, you can earn a certificate. I found “Galaxies and Cosmology” given by a Caltech professor. This class already ended so I’m taking it self-paced. There are short quizzes mixed into the video lectures. This class has tests at the end of each week and no other assignments or final exam. You do need 1st year calculus to really understand the concepts.  (I missed this in the first short quiz: ∫10 ex dx. Sigh.)

Allergic to math (or at least calculus)? I’ve also sign up for “From the Big Bang to Dark Energy”. There is a “basic” track that requires just high school algebra/geometry and an “advanced” track for those who are gluttons for punishment  It runs for four weeks from 8/5 to 9/1  I’d encourage EVERYONE to sign up and get the certificate. You can always ping me for help. If you decide to jump in, do let me know!

Ceres and Vesta

S&T and other sources have noted that the asteroids Ceres and Vesta are now visible. They’ll both continue to be in the same binocular view for a while. I’ve seen them the past couple weeks and, courtesy of Tom Pillar, saw them at Rancho through his telescope in a 2° field of view. It turns out they’ll be closest together around July 4th. Because they’re small, you have to know exactly where they are. Otherwise there’s no way to distinguish them from stars.

If you haven’t seen them yet, you should! Being able to see both Ceres and Vesta in the same view is a rare occurrence. Although they’re both in the asteroid belt, their orbits are somewhat different. It turns out they get close to each other only once every 16 years. The next time they’ll be within 5° of each other will be Feb. 2030 and, drum roll please, the next time they’ll be within 2° is 2081!

So how do I know that? Did my Magic 8-ball tell me? Ha! Anyone who has known me a while knows that I make heavy use of Sky Safari. If you care to try the same exercise as I did, just follow along. This works well if you have the plus or pro version. If you have the basic version, you don’t have the capability to show field of view circles, so there’s no direct way to tell angular distance as asteroids fly by.  You can also do this with other software, but it’s MUCH easier if you have field of view circles.

Let’s set up field of view circles and turn off certain objects. In Sky Safari zoom in or out so your display is about 30° wide. You can search for Ceres or you can move your view so Mars is visible. As of this writing, they’ll be slightly above and to the left of Mars. Select Ceres and hit “Center”.

Go to “Settings” -> “Deep Sky Objects” and turn off deep sky objects. Similarly under “Solar System” turn off planets, but turn on asteroids, names, and at the bottom set the limiting magnitude to 11.0. To help you gauge the part of the sky you’re looking at, turn on constellation names. Also make sure your horizon is off (or on with either “Transparent With Line” or “Translucent Area”). [Note: All this is to prevent various objects from becoming distractions, like planets, as the whiz by at high speeds.]

Set one field of view circle to 10° and another to 4° and turn them both on. For Sky Safari version 3 go to “Display” and change the fields next to “Finder”, “Wide”, “Narrow”. For version 4 go to “Display”, turn on two “Custom Filed of View”, tap, and enter a new field of view. Hit “Done” to return to the view screen.

You should now see Ceres in the middle of the two field of view circles. Since we’ll have Ceres centered in the circles, anything inside the 10° circle will be at most 5° away, and anything in the 4° circle will be at most 2° away.

Select the “Time” menu set your time to 10pm. Select “Day”. Now hit the fast forward button. You’ll see Vesta move away and other changes as Sky Safari shows you how the sky changes as the days fly by.

You’ll notice the other (relatively) bright asteroids come and go. Eventually you’ll see Vesta swing into view around Feb. 2030. Hit the fast forward button again to stop and again to restart. Fast forwarding can take a long time, so you may want to bump up the numerical increment on the left to 10 or higher. If you’re running on a Mac (or other program on a laptop or desktop), the fast forward is faster (and looks smoother), so your increment won’t have to be as high. When something interesting comes into view, you can stop and bump the increment back down to one.

Here are the dates I found where Ceres and Vesta are close together:
2/2014 – 8/2014: ? (How close will they get?)
2/2030 – 5/2030: 3°
2047: ?
2065: ?
4/2081 – 6/2081: 1°, but visible only during pre-dawn hours

To find the exact angle between two objects, select the first object (if not already selected), select the second object, and hit “Info”. You’ll find the angle under “Angular Separation”. Be sure to reselect Ceres and center before restarting fast forward, otherwise Ceres will disappear from view.

Once you have this under your belt, you should be able to predict any imaginable event the solar system offers!

Posted in My Favorite Things

My Favorite Things, Vol. 1.3 – Trek/There’s More

Star Trek

It’s amazing what this 60s TV show did. It lit up the imagination of the public and inspired the generations since to pursue science and engineering. NASA recently presented an award to William Shatner. He narrated this short Space Shuttle history video.


Electromagnetic Spectrum Blindness

Sometimes there’s more than “What you see is what you get.”

For the past 400 years we’ve had great improvements in telescopes. Just a look at a few images taken by the Hubble Space Telescope will convince anybody that’s true. And with that you might not even think to ask: “Is there’s more?”

Imagine being colorblind and able to see only green. You’d be able to read this blog (unless someone was really mean and set your computer to display any color but green), drive a car, and do any number of other things, but still…. Then if you gained full vision, you couldn’t help but see all the things you couldn’t perceive before.

Until the advent of electronics in recent decades, we were in a manner of speaking electromagnetic (EM) spectrum blind — we could see what’s in the sky through only a tiny part of the EM spectrum. Notice in the diagram below how narrow the range of visible light is compared to the entire spectrum and how much the atmosphere blocks.

[source: Wikipedia]

We’ve had radio telescopes for decades and in just the last 10 to 20 years we’ve started to get good images in the infrared, ultraviolet, X-ray, and gamma-ray. In other words we can “see” just about everything else now. Now try to imagine the excitement astronomers experienced as they were first able to observe in each of these new EM regions.

Different EM regions give different clues. Like any good detective (Hardy Boys and Nancy Drew, anyone?), astronomers are putting these different clues together.

One nice example of this is shown in a recent S&T article about a specific supernova. The first frame shows radio, then infrared, then visible, then X-ray, and finally all four. (Obviously, except for visible, the images are shown in a false color since we can’t directly see them.) Each shows the same region of space but different aspects of the supernova. Read the article for details.

This type of multispectral imaging has become more prevalent over the past several years, and this trend will only continue to grow.

So what happens now that we’ve been cured of EMSB? (What an acronym!) Does this mean there are no other means to observe the universe? I’ll let you think about it until next month. You’ll see!

Till next time, Clear Skies!

Posted in Articles, My Favorite Things

My Favorite Things: Vol 1.2 – Hubble DVD Course for $10

I wasn’t planning to put out the next post until next month, but just found a really good deal.

Great Courses is offering their DVD Course on Hubble Space Telescope pictures for only $10 (+S&H)! Look for “Experiencing Hubble: Understanding the Greatest Images of the Universe”. Other courses are on sale, too.

We’ve shown a couple sessions over the past couple years at Houge Park and I have it myself. This one’s a STEAL!

Posted in Articles, Blog, My Favorite Things

My Favorite Things: First blog

My Favorite Things

Rain drops on roses and whiskers on kittens!

“Sound of Music” is one of my favorite movies. My baritone voice is nothing like Julie Andrew’s, but I digress!

Astronomy is such a diverse field. I think most people normally think of astronomy as science, but to me, and I think you’ll agree, it’s SO much more. Astronomy is also art (paintings like Van Gogh’s “Starry, Starry Night”), poetry and music (LOTS of examples of those), photography (which is arguably also art), history, mythology, and even astrology (in a historical context, I mean). And for those who ask “Why?” one can also add philosophy to the list! But all of that is for naught if not for the personal “Wow!” factor we all experience.

My hope is that this is the start of a monthly blog about astronomy (duh!) that I think SJAAers will find interesting.  I’ve been a science buff since I was little, so most of what you’ll find on “MFT” will be science but on topics that I think has a “coolness” factor and that will catch the eye of the general public.

LADEE to Bite the Dustee
NASA’s LADEE lunar probe has completed its primary objectives and is scheduled to impact the moon around April 21.  You can enter their contest to guess when the actual impact will occur (deadline is April 11).  The NASA article and the link to the contest are here.

Incidentally our July speaker will present on LADEE!

Sky Safari 4.0 for Android — On sale!
The latest version of our favorite astronomy app is now available on Android and is half off until April 21.  Observers should get either the “Plus” or “Pro” version.  At half off the Pro version is just $20!  [Note 4.0 is a completely different app from the previous version, so there’s no discount upgrade path.]

For details on their iOS, Android, and Mac OS products, see here.

Till next time, Clear Skies! (And of course comments are always welcome!)

Posted in My Favorite Things