2005 YU55
Image of asteroid 2005YU55 by Brian Kimball
News
How Far Away is Vega?
By Bill Pellerin
Houston Astronomical Society
GuideStar Editor
At our annual Astronomy Day event, I’ll often point to Vega and say, “That star is 25 light-years away and this means that the light takes 25 years to reach us.” But, how do we know that Vega is 25 light years away? How did we determine this?
This is an interesting subject. Even the distance to the Sun wasn’t well determined until the 1960’s when radar ranging was used to measure the distance. The process is easy, send a radio pulse to an object, and see how long it takes to get there and bounce back. If you know the speed of the radio pulse, and we do, it’s easy to calculate the distance using the formula we learned in high school — d=r*t. That is, the distance is equal to the rate (speed) multiplied by the time. Since the radio pulse has to travel to the object and back the calculation for this is d=r*t/2.
Nebulae – and the Lifecycle of the Universe
By Bill Pellerin
Houston Astronomical Society
GuideStar Editor
Last month, I wrote an article about the way we categorize nebulae (clouds in the sky). There are emission, reflection, and nebulae, which tells you how they are visible to us. The other way to categorize nebulae is as pre-stellar (star forming) and post-stellar (a remnant of a burned out star). I recently viewed the Wonders of the Universe video series by Brian Cox (highly recommended) and one of his subjects is the lifecycle of the universe and how objects in space fit into that story. That is, if we look at how the universe began, how it got to where it is today, and the future of the universe we get another perspective on nebulae.
So, let’s go all the way back to the beginning of the universe, the Big Bang. Various light elements came into being as the result of the Big Bang, but the heavier elements did not. The Big Bang, while extremely hot was also of short duration. In other words, there was not enough time for heavier elements to form as a result of the Big Bang. This formation of elements as a result of the Big Bang is called ‘Big Bang nucleosynthesis’.
What the universe began with, and what were the building blocks of the future universe, were (75%) hydrogen, (25%) helium, and small amounts of lithium and beryllium. That’s it. No carbon, oxygen, or anything else existed yet existed. The universe had to wait for these elements to be formed.
Nebulae – Clouds in Space
By Bill Pellerin
Houston Astronomical Society
GuideStar Editor
When you look at the sky, what do you see? On a clear night, you’ll see stars, perhaps the moon, perhaps one or more planets. Do you ever see clouds in space? They’re a bit harder to see than many of the bright objects, but they are often the most interesting objects in the sky. These objects are generally called nebulae (the plural of nebula) and the word ‘nebula’ is from a Latin word meaning ‘cloud’. They don’t look like small points of light; they look hazy and, well, cloudy. For a long time, we didn’t know what these objects were, but now we do. If you listen, you’ll often hear observers say that an object is ‘non-stellar’ – meaning that it is not a star – meaning that it is nebulous.
Let’s begin with a bit of history.
One of the kinds of nebulae seen by early observers was a spiral nebula. One of the first observers to see these spiral nebulae was a British fellow named William Parsons, the 3rd Earl of Rosse. In 1845, he built a very large telescope – called the Leviathian. With this telescope, he saw the spiral structure of M51, the object we now know as the Whirlpool Galaxy. In 1889, Vincent Van Gogh painted the famous ‘Starry Night’ which includes a spiral shape in the sky thought to be inspired by the drawing of Lord Rosse.
The Contrariness of Things
By Bill Pellerin
Houston Astronomical Society
GuideStar Editor
As observing equipment and imaging systems become more complex the likelihood that something will happen contrary to your expectations increases. I touched on this issue in a previous article about how it is necessary to really learn how our equipment works, in excruciating detail. Many times the problem is not the equipment, it’s our expectations or it’s our lack of knowledge.
The telescope mount that I use requires that several alignment stars be located (by me) as part of the setup process. While the process makes sense, now that I understand it, for a long time it didn’t. It didn’t make sense at first because it was different from other telescope mounts that I had used in the past. I was executing the process in the wrong order – expecting to first tell the mount that I was going to point it to an alignment star instead of moving the mount to the star and then telling the mount that I did.
If you’ve even been to a dog training class, you know that the class is more about training the owner and less about training Fido. That’s often the case with the equipment we use, using it is more about training the owner than making the equipment bend to the will of the owner. You have to get into the head of the equipment designer and understand his or her thinking when the equipment was created.
Are You a Serious Observer?
By Bill Pellerin
GuideStar Editor
There is a lot written and said about amateur astronomy, but one thing I hear often is that someone is a 'serious observer' (not to be confused with a Sirius observer, which would be easy). Are you a serious observer? Am I?
I've heard it said that it's a requirement to be called a 'serious observer' that you own a large telescope.
Astronomy magazine's podcast (by Michael Bakich) offers observing objects for various sized telescopes. Early on, Michael referred to large telescope owners as serious observers. After receiving feedback from listeners with smaller telescopes, he doesn't make this association any more.
Phil Harrington, whose latest book is Cosmic Challenge said in an interview in our Houston Astronomical Society's GuideStar newsletter (in an interview written by Reflector contributor Clayton Jeter) "I believe in 'go big or go home'". By this, Phil means that you should have big goals, and you should try big things, but doing so doesn't necessarily require big telescopes. In fact, you can take a deep a dive into many observing programs with a good pair of binoculars. Phil responded to an email with, "In my mind, veteran observers should put themselves and their equipment to the test by trying to see targets that are at the edge of visibility for their instrumentation." Objects may be on the edge of visibility because they are dim, because they are small, because they are close to bright objects, or because they are difficult to identify in a crowded star field.
Barnard's Star is an example. It's a magnitude 9.5 star in Ophiuchus, but it is a bit of a challenge to find in a crowded star field. The star moves over 10 arc-seconds per year, so you have to know exactly where to look for it.
So, what are the characteristics of a serious observer? I exclude the requirement that a 'serious observer' only observes very dim objects with very large telescopes. So, if the quality of seriousness is not associated with equipment inventory, what is it?
Someone who is a solar observer and regularly (every clear day, for example) observes the Sun and records those observations with the intention of developing an in-depth understanding of solar phenomena is a serious observer. The Sun is the brightest object in the sky, so if someone can be a serious solar observer, then clearly any object, or set of objects observed in a serious manner can make an amateur astronomer serious.
There are plenty of observers of the Moon. While the moon has been observed, mapped by satellites, and visited by humans, not everything there is to know is now known. The work on lunar observing is not complete. My fellow Houstonian, Brian Cudnik has written a book, Lunar Meteoroid Impacts and How to Observe Them. Brian observed a meteor impact on the Moon visually in 1999 and discusses in his book opportunities for amateurs to participate in serious lunar observation.
Various observing organizations such as ALPO (Association of Lunar & Planetary Observers) coordinate efforts of observers of solar system objects, IOTA (International Occultation and Timing Association) works on lunar and other occultations, the AAVSO (American Association of Variable Star Observers) collects data from amateurs on variable star brightness over time to provide data to professional astronomers who are trying to understand stellar evolution.
Another friend of mine concentrated on seeing the earliest possible new moons (and latest possible old moons). He'd travel hundreds of miles to be in the best place to make the observations. Sounds serious to me.
The common characteristic of these organizations, and these observers, is the depth of effort and the depth of knowledge required to make the observation. These observers are not content to casually observe objects in the sky, they want to study the objects, they want to understand what they are observing and how the object fits into the universe.
How do you get to be a serious observer? You get there the same way you get to Carnegie Hall… practice, practice, practice (and effort). I read an article in the Scientific American ("The Expert Mind" July, 2006), and it said that the way you become proficient at something is by purposeful effort. Half-hearted effort won't get you there; your observing program must have a goal and a purpose and effort in the pursuit of that goal is required.
My observing purpose is to provide data on a regular basis to the AAVSO on variable stars with a goal of providing information that advances the understanding stellar evolution. I'm working on improving my data gathering and analysis processes and being able to provide more and better results.
The Astronomical League observing programs have introduced many an observer to object categories he or she would not have otherwise observed. These programs can lead to a passion for any of these objects and represent a valuable service to the astronomical community. Check out the observing clubs on this web site and see if any look interesting to you. Years ago, I completed the double-star club, and I've been a double star observer ever since.
If you can't decide on one, do the Universe Sampler club by Amelia Goldberg. You'll get introduced to many objects in the sky in the process of completing this one program.
You will be able to tell when you have become a serious observer; you'll be observing with a purpose and having more fun, too.
American Astronomical Society’s Chambliss Amateur Achievement Award
Nominations for the American Astronomical Society's Chambliss Amateur Achievement Award are being accepted, with a deadline of June 30, 2011.
The award is made for an achievement in astronomical research made by an amateur astronomer; that is a person not employed in the field of astronomy in a professional capacity, and who is resident in North America. The key factor is that the work contributes to the advancement of the science of astronomy.
The nominator should send basic information about the nominee (including contact information), a description of the achievement being singled out for recognition (including any scientific paper references), and a statement as to why this amateur and this work are worthy of the award.
Nominations are welcome either electronically (aassec@aas.org) or by mail
G.F. Benedict
McDonald Observatory
1 University Station
Austin, TX 78712
The nomination form is at http://aas.org/files/Chambliss_Award_Nomination_Form.pdf
Amateur Astronomy – a solitary activity… best done with friends
by Bill Pellerin
Houston Astronomical Society
GuideStar editor
An amateur astronomer is one person, with one telescope, observing under clear, dark skies, right? It's you, your telescope, and the sky. Much of my observing is like that, but not all. You can (and you should) connect with fellow amateur astronomers because these connections can significantly enhance your observing program and your appreciation of the night sky.
Recently, I had dinner with one of my long-time astronomy friends. We were chatting about the issues he was having with his research-grade instrument and control system and about my equatorially mounted setup. We talked about how the control systems model the sky, the accuracy of pointing systems, the benefits of adding software that improves pointing, and so on.
I talked about my variable star photometry program (measuring the brightness of stars) and how some of my unguided images have tracking errors and had to be discarded from the image stacking process. Then, he mentioned the PEC (periodic error correction) capability of my mount and asked if I was using it. Uh, no, I haven't been. This is one of those 'duh' moments when you realize that you have a capability and you're not taking advantage of it. So, I'm going to work with my mount's PEC capability, learn it thoroughly, and see what it can do to improve tracking. Sometimes, you need a friend to remind you of the obvious.
The (Near) Future of Amateur Astronomy
By Bill Pellerin
Houston Astronomical Society
GuideStar Editor
Amateur astronomy is changing, again. This change is being driven by technology, the Internet, and the overwhelming amount of astronomical data now available. In the over 20 years that I've been in amateur astronomy I've seen large (often Dobsonian) telescopes come into our hands, we've seen the incorporation of computers and technology into telescope designs, and we've seen amazing advances in astrophotography.
Energize Your Astronomy
By Bill Pellerin
Houston Astronomical Society
GuideStar editor
Do you find yourself setting up your telescope and then asking yourself, “What am I going to look at?” Or, have you missed a clear dark night because you can’t think of anything that you want to observe. I hope, in this article, to convince you that by focusing on one or more areas of astronomy and delving deep into those areas that your astronomy ‘career’ will take off. What’s more, if you do that, you will never run out of things to observe.
Perhaps it’s time to change how you approach your observing. If you’ve been something of an ‘astronomical tourist’ (someone who looks at objects, says, “how nice”, and moves on) and it’s time to pick your area of interest and do a deep dig into that subject. It has been my observation (pun intended) that those who are most enthusiastic about their observing program are those who really, really understand what they’re looking at and why it’s interesting. These are the same observers who have taken the time necessary to learn about the objects and who understand the object’s place in the cosmos.
