Posts Tagged ‘Voyager’

By Mike Hubbartt, © Copyright 2010, All Rights Reserved.

Saturn Facts:

  • Location: 6th planet from the sun
  • Size: 2nd largest planet in our solar system
  • Orbit: 9.54 AU
  • Orbital Period: 29.44 Julian Years *
  • Average Distance from Earth: 9.58 AUs *
  • Diameter: 120,536 km
  • Discovered: 1610 by Galileo
  • Atmosphere: 75% Hydrogen, 25% helium
  • Interesting facts: visited by Pioneer 11, Voyage 1&2, Cassini. it has rings, internal heat source.
  • Total number of moons: 61 (Tarqeq, Pan, Daphnis, Atlas, Prometheus, Pandora, Epimetheus, Janus, Aegaeon, Mimas, Methone, Anthe, Pallene, Enceladus, Tethys, Calypso, Telesto, Polydeuces, Dione, Helene, Rhea, Titan, Hyperion, Iapetus, Kiviuq, Ijiraqm Phoebe, Paaliaq, Skathi, Albiorix, S/2007 S2, Bebhionn, Erriapo, Siarnaq, Skill, Tavros, Greip, S/2004 S13, Hyrrikkin, Mundilfari, S/2006 S1, Jarnsaxa, Narvi, Bergelmir, S/2004 S17, Suttungr, Hati, S/2004 S12, Bestla, Farbauti, Thrymr, S/2007 S3, Aegir, S/2004 S7, S/2006 S3, Kari, Fenrir, Surtur, Ymir, Loge, and Fornjot)
  • Click here for Wolfram|Alpha data on Saturn

* = Courtesy of Wolfram Astronomy Assistant

One of my favorite hobbies is astronomy, but I’m currently without a decent telescope so I take advantage of computer software and the internet to satisfy my desire to explore the heavens.  I have two favorite astronomy packages – Starry Night and Voyager – both are loaded with features and very good for people with passing interest in the stars and planets, as well as more serious hobbyists.  Right now I am testing and reviewing Redshift 7, another astronomy package for Windows, and I’ll post my review here as soon as my evaluation is complete.

This evening I started Starry Night up after booting my Macbook and took a quick jaunt to Jupiter and Saturn. My last astronomy post dealt with Jupiter, so let me discuss Saturn tonight. Saturn is a gas giant, is the second largest planet in our solar system, and is the 6th planet from the sun. Most people know about the rings surrounding Saturn, which are made of ice and rocks.


As you see at the left of the screen, we’re looking at the Starry Night Find tab and see some data about the planet and moons. If we want more data then we need to switch to the info tab and select the More Options button.

Quite a few options. If you need more information about this gas giant, select the Extended Options button, which launches Safari and looks for information on Saturn in Wikipedia.

Now for a view of Saturn as seen from the surface of Enceladus, the sixth largest moon of Saturn and one of only three outer solar system bodies (in addition to Io and Triton) where we have been able to observe an eruption:

When I think of the first astronomy program I used on a computer (an open source program), I am amazed and pleased how far this genre of software has evolved over the years. Instead of sitting out in the cold and hunched over a textbook to glean data about dim astronomical bodies, we can learn about the planets and stars in our classrooms, homes, and as we travel.

The current generation of people in high school and college will have the opportunity to travel into space on one of the commercial space craft now being developed. I imagine that same generation will be able to travel to the moon and maybe even to Mars. If this interests you even a little, take the time to set aside time spent watching TV or playing games and see some of the wonders in the skies above you. The images of planets and stars now available to people is impressive, and what you see now may be something you see in person in the future.

I should also mention that people using iTunes should check out iTunesU. Professor Nemiroff at Michigan Technological University has posted all of his lectures for PH1600, a college-level introduction to astronomy. They are informative, easy to watch, and absolutely worth the time to download and view. There are other astronomy courses at iTunesU, so take the time to check them out.

Until then, be well.

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Updates

6-24-2011 – Added Orbital Period, Average Distance from Earth Information.

2-14-2011 – Added names of all moons.

Voyager 4.5.7 Sky Simulator
Carina Software (Phone: 1- (925) 838-0695, Mon – Fri, 9:00 AM – 5:00 PM PST)
Website: www.carinasoft.com
Price: $179.95 w/DVD, $129.95 w/2 CDs, w/CD download $99.95
Upgrade prices and educational discount information available at Carina’s website.

By Ted Bade, © Copyright 2010, All Rights Reserved.

Introduction

Astronomy buffs or anyone looking for a solid astronomy simulation program should take a serious look at the Voyager Dynamic Sky Simulator software package developed by Carina Software. It offers a good user interface, easy to understand controls, along with the ability to control computer driven and certain motorized telescopes. Voyager provides a huge sky catalog, complete with images and a variety of ways to view the skies. It will satisfy just about any amateur astronomer’s needs.

Let me qualify myself on the subject of Astronomy before I begin this review. I am a true amateur, who enjoys employing technology to make observing the sky more fun and informative. I own a decent computer controlled telescope, (6” Newtonian), and I live in southern New England (USA), where light pollution and overcast skys are the norm. It is important to me to own a good sky simulation program, so I can plan for those few nights when the sky is clear and I can actually use my telescope to view the sky. It’s also important that the program can help me learn what my sky would look like if the clouds (and light pollution) weren’t there.

My experience with Astronomy software packages has been using Starry Night Pro and an earlier version of Voyager (3.x). My apologies to those people who have written shareware programs, I have not taken the time to give any of them a serious look, (but I am open to doing that).

I would like to explain what a sky simulation program does, for those of you who might not be familiar with this type of software. We are all familiar with planetariums, an auditorium with a domed ceiling on which is projected a simulation of the sky. Although they are used mostly for entertainment, their real purpose is to allow us to study the motion of stars. Combining what we have observed in our short history with the laws of physics and motion, scientists can predict the motion of the stars, and be able to simulate where they have been and will be at any time. Using this technology, a program can display what the sky looks like from any point on the earth at any time in the future or in history. Obviously, the simulation cannot predict unexpected events and is limited by the mistakes we have made in calculations. But it is pretty accurate and I doubt I will ever observe a mistake in my lifetime.

System Requirements

Voyager runs under Mac OS X or Windows.

Mac Mac OS X

  • Mac OS X 10.4 or higher
  • PowerPC or Intel 1 GHz or faster processor (2 GHz or faster recommended)
  • 700 MB of hard disk space (4.2 GB for DVD version)
  • 512 MB of memory (1 GB recommended)
  • 1024×768 display with 32-bit color
  • CD-ROM drive (for CD version) or DVD-ROM drive (for DVD version)

Windows Windows

  • Windows XP or Vista
  • Pentium 1 GHz or faster processor (2 GHz or faster recommended)
  • 700 MB of hard disk space (4.2 GB for DVD version)
  • 512 MB of memory (1 GB recommended)
  • CD-ROM drive (for CD version) or DVD-ROM drive (for DVD version)
  • 1024×768 display with 32-bit color
  • Adobe Reader or similar software to view on-line User Guide in PDF format

Using the Software

With this software, you can see what you sky will look like tonight, next year, or even a thousands years ago. You can view what the sky would look like from many locations, your back yard or places you might never visit like Australia, the north or south pole, or even the moon! While it is not currently available in this version, I expect in the future advanced features should let you explore the surface of planets and moons that we have data on.

I am not going to try to analyze the validity of the star catalog and other astronomical information provided in Voyager. I am no expert on this subject and I trust that a reputable company like Carina checks the data. The program can check for updates that give the latest information and ephemerides (orbital data) for comets, asteroids, and satellites. It also will check for updates to the application. I am reviewing specifically version 4.5.7, which is the current version as of this review.

Voyager’s main window is the Sky Chart. This is your view of the sky. You can have more then one sky chart open at one time. A reference line near the bottom of the window represents the circle of the horizon around where you “stand”. In the program the line shows the cardinal points (N, NE, E, etc.) and is also marked in degrees, with North being zero. When you click and hold on the screen you can move the view around the horizon or up and down. As you do, the view of the sky changes as if you were moving your head to look at different parts of the sky. Additionally, when you click and hold, small windows pop up displaying the current altitude and azimuth of the center of the screen a great feature to let you know where you are, especially in more zoomed views.

How much of the sky you see on a single screen is controlled by the Zoom window. The default is set to about what a human would see standing outside. You can zoom in or out from this view using the zoom controls. Zoom in far enough and you will see the object as if looking with a powerful telescope, zoom out enough and the view of the sky becomes a bowl.

The star field you see will be what you might see if the sky were perfectly clear and dark. Voyager falls a bit short on simulating light pollution, for those of us who would like to see an image of the sky as we see it. You can choose to show a “Natural Sky” which brightens when the sun is up and darkens as it sets. But there are no controls to simulate the effects of the lights of a nearby city. You can control the minimum brightness of stars to display. If you know your local limitations, this can be used to show only those stars or objects that you could actually see wit ha naked eye.

In the real world, you cannot see below the horizon, so you can chose to fill in the areas below the horizon. Voyager offers different options from just opaquing the area below to using a photo. Since most users don’t live in an area with 360 degrees of unobstructed horizon, the images obstruct a little above the horizon as well. The program comes with a handful of photos to use. My home location includes a lot of trees that block a good portion of the lower sky. I was pleased to find that you can create your own image, if you have the time and patience to do it. Instructions are provided with the program, but I didn’t give it a try.

Voyager does a lot of things, offering many ways to simulate the sky and the objects one can see. There are many very useful tools included in the package. One could easily write volumes about all the things that can be done. For this review, I am going to hi-lite some of the features I found especially useful. If I don’t mention a feature you think is important, check with Carina Software to see if Voyager does that.

Voyager lets you easily turn on and off all types of labels and information related to the sky. A name label can be shown for every object that can be shown on the screen. By default the popular name (if one exists) is shown, and there are plenty of options for selecting a specific list or catalog number. There are a lot of stars and other objects in the sky. If you turned on all the labels, the sky would be covered with the labels. Voyager offers a couple of options for limiting labels. The best one for naked eye observations is to limit labels to those stars of a certain magnitude or greater, which can be adjusted by the user. There is also a very nice option to show spectral colors for stars.

Planets and moons, when observed from earth, might be seen as having phases. You can choose to show the phases or not. What this means is that when looking at the Earth’s moon, the program will display it with the same phase as it currently has. In addition to moons, you can show asteroids, comets, and satellites on your simulated sky. There are options for how these show and how they are labeled.

I found the comet options especially useful. At the time of this writing a comet was passing our night sky (103P Hartley2). The comet had a magnitude of 5.3, which means it might be visible to the naked eye or a good pair of binoculars. On the screen it shows as a typical comet symbol. Using Voyager, I was easily able to locate where to sight my binoculars to see the comet in real time. I was also able to plan the best time to go out for the observation, ensuring the comet was above the trees in the open sky.

There is a lot of stars and other interesting objects in the sky that are not visible to the naked eye. You can tell Voyager to put symbols on the screen showing a symbol for the object at the location and even the name of the deep sky object. This is very useful for creating a list of objects to observe. What I did was set Voyager to the time and date I planned to take my telescope out, and then use the symbols to locate objects in the sky. Knowing the limitations of my telescope and sky, I could then select a variety of objects to try observing.

If you mouse over any star or object, it’s name (if it has one) or star designation appears on the screen. If you left click on it, an information window pops up. The pop up window provides various bits of information about the object depending upon what is available. The information window offers information, images, and some controls. Getting the mouse on the correct point was relatively easy for stars, but a lot more difficult for the symbol of the comet, since the point you have to have the cursor on is significantly smaller then the symbol.

Voyager does a great job of simulating the sky. It offers many images of popular objects. One thing that is especially interesting is the ability to link to another sky chart, allowing you to see a simulation of an event from two different locations at the same time (provided you have enough screen space!).

Conjunctions are very popular viewing events, since they generally can be see without a lot of special equipment. Also, some major historical events occurred along with significant conjunctions. Voyager includes a “Conjunction Search” tool that will search a range of dates for Solar Eclipse, Lunar Eclipse, or Planetary conjunctions. The range of dates you can search includes 498000 BC to 502000 AD. The search creates a list of events indicating what time and date they occur and whether they are visible from the location of the sky chart you currently have opened. Voyager doesn’t provide any information to help if the event isn’t visible from your current location.

Another nice tool is the “Planetary Report”. This tool provides various information pertaining to planets in our solar system and some major moons.  A pull down menu offers many types of information including distance to the object, phases, rise and set times, apparent magnitudes, and more. Some very useful information for the backyard observer. For instance, you can plot a chart showing where the major moons of Jupiter will be, so when you observe, you will know which is which. Along the same lines, there is another tool that plots the orbits of specific man-made satellites from a giant list of choices. After looking at this list, I was amazed at just how much stuff is up there!

Other tools Voyager provides are more scientific in nature, although they can help with observing as well. The Binary Star Orbit tool lets you choose a known binary star system from a huge list. Choosing a system brings up a graph, many of which can be animated to show the secondary orbiting the primary star. This tool offers a number of ways to organize and search for the binary system as well as facts about the stars. You can even center the chosen binary on the main sky chart, to see where it is in the sky.

There is a Star Survey tool, which provides a graph of information concerning the stars in the program’s database. Options are Star count by distance or magnitude, Color magnitude diagram, and Mass-Luminosity. The tool lets one select from all or various sets of stars.

There are three tools to simulate views off the earth. The solar system gives a view of the solar system from 1 to 200 AU (Astronomical Units *1) out.  The Solar neighborhood chart that simulates a view with our sun at the center, showing the universe from 20 to 4000 ly (light years *2), and a Redshift Distribution Chart. All these charts are interactive and simulate a 3D view. You can use sliders to change the orientation of the chart. The first one also lets you see the orbital motion in large time increments. Each of these charts provides a bunch of information related to the topic. A lot of fun and a great tool to use to learn about the stars.

*1 – An Astronomical Unit equals the average distance between the Earth and the Sun, which is approximately 150,000,000 kilometers (93,000,000 miles). Mercury is 1/3 AU from the Sun, while Pluto is 40 AUs from the Sun. AUs are typically used for measurement within the solar system, and light years are used to measure distance between the Sun and objects outside the solar system. – Ed.

*2 – A light year is the distance that light travels in 1 year, which is 9,500,000,000,000 kilometers. – Ed

Voyager and Telescopes

Voyager 4.5 can control a variety of telescopes with computer controls. There is a large list of options, including controlling a telescope that has just drive motors and no computer. I found connecting to my Meade LXD75 to be very easy. All options to set up the program for working with a telescope are in the “Telescope” menu. To turn on the controls, you first need to know and set up the specifics for your type of telescope. This includes the type of telescope you are using, (there are over 30 options for many popular manufacturers), the correct communication port, Baud rate, and telescope mount type. Choosing the telescope type doesn’t automatically select the standard mount type. For instance, my LXD75 comes standard with a German Equatorial mount, byt Voyager defaults to equatorial fork. Which means you need to consider all the choices before making the connection.

Since this is a real time connection, you cannot do much with it until you have hardware connected. For instance, I use a serial to USB interface to make the connection. This option doesn’t show up until the interface is actually connected between the telescope computer and the MacBook. However, you do see other communication ports that the MacBook has. Align your telescope if necessary before making the connection to Voyager.

Once the connection has been made a telescope window pops up, showing some information about the connection. The view of the sky also changes to align with the orientation of you telescope. Since the program has no way to know what eyepiece you currently have in the telescope, the field of view remains where every it was. I like keeping the zoom level the same as normal eyesight. This way, I can look at the screen, and then at the same area of the sky, to make sure there isn’t an obstruction before slewing the telescope to that location.

Assuming your telescope is properly aligned, you can select anything you can find in the Voyager program and slew your telescope to that object. The alignment process for lower end scopes (like mine), isn’t an exact or easy process. Even with a very good alignment, the scope is off by a little bit. But a little bit is a lot when you consider the effect a small error has when trying to find something thousands of light years distant! After the scope has moved to where it thinks an object should be, one normally fine tunes the position to center it in the viewfinder. Once it is centered, there is an option in Voyager that lets you feed back to Voyager that this is where the object really is. By doing this with several objects, one hopes that this improves the alignment of the scopes computer making it easier to find objects as the night goes on.

There is an option to turn on “night vision” when connected to the telescope. This feature dims the screen and gives it a red hue. Doing this is similar to using a red flashlight, you can see it, but it doesn’t reduce your night vision ability. This effect extends to other applications you might have running, in case you switch to them. I will often listen to internet radio when I am out with my telescope and sometimes will have a need to check something on the internet. By affecting all applications, this means that switching to another App doesn’t kill your night vision.

By default, the Voyager screen is locked to the view of the telescope. This can easily be switched off, allowing you to scan the skies as shown by Voyager, for an object to visit. Once an object is located, select to move the telescope to it. Pretty easy.

If you are organized and plan your night session, Voyager offers an observing list. Before your nightly session use Voyager to plan what objects in the sky you intent to observe. Add the ones of interest to the observing list. When the telescope is attached to Voyager, there is an option to “Go To” the object on the list. The observation list provides other options as well. You can jump to the objects information screen, show the object on the sky chart (a flashing circle appears around I for a few seconds), or move the telescope to it.

Issues

The only issue I had with Voyager’s interface was that the telescope command is at the bottom of the standard object right click menu. It is a long list, and for most objects many of the standard choices on this menu are grayed out (not functional). It’s a minor issue, but still inconvenient! This leads to another complaint: this menu isn’t contextual, so the same menu is shown for every object, whether any of the options are valid or not and there are many that apply to only planets. While non-valid options are grayed out, they still take up menu space.

Conclusion

There is a lot more that one can do with this program. As I mentioned, I discussed only a few of the items I found most useful. Voyager is a true encyclopedia of the sky, with many options for accessing and viewing the data it contains. One could easily spend hours just perusing the skies Voyager simulates, looking for interesting objects, learning about them as well as looking at some very nice images. It’s a terrific program.

This version of the Voyager Sky Simulation program is a great tool for learning about the skies above us and a useful tool to help people interested in astronomy and observing the sky with both the naked and enhanced eyes. I am not sure I could easily choose a favorite between Voyager and the other commercial applications I have tried. All the information is available in these programs, but the methods that the information is made available or accessed is different. I have been using Starry Night Pro plus as my telescope assistant tool for a number of years. As I tested Voyager, at first I was put off by these differences, but as I continued using it, I realized that some of the differences actually make sense as well as streamlining the process. I doubt I will be able to make a final choice until I have used Voyager for a lot longer time.

Recommendation

If you are considering buying a sky simulation program that provides many tools to help with your observations of the night sky, you should definitely consider Voyager. Price-wise it is competitive. Choices include a DVD version (with a lot more star/object information) for $180, a two CD version with less information but all the important stuff for $130, and an option to download the CD version for $100. The boxed versions come with a printed manual (a nice feature these days). I highly recommend giving this program a close examination; it will be worth your time.

By Mike Hubbartt, © Copyright 2010, All Rights Reserved.

Jupiter Facts:

  • Location: 5th planet from the sun
  • Size: largest planet in our solar system
  • Orbit: 5.2 AU
  • Orbital Period: 11.86 Julian Years *
  • Average Distance from Earth: 5.26 AUs *
  • Diameter: 142,984 km
  • Discovered: 1610 by Galileo
  • Atmosphere: 90% Hydrogen, 10% helium
  • Interesting facts: visited by Pioneer 10&11, Voyager 1&2, Ulysses
  • Total Number of moons: 63 (Metis, Adrastea, Amalthea, Thebe, Io, Europa, Ganymede, Callisto, Themisto, Leda, Himalia, Lysithea, Elara, S/2000 J11, S/2003 J12, Carpo, Euporie, S/2003 J3, S/2003 J18, Orthosie, Euanthe, Harpalyke, Praxidike, Thyone, S/2003 J16, Iocaste, Mneme, Hermippe, Thelxinoe, Helike, Ananke, S/2003 J15, Eurydome, Arche, Herse, Pasithee, S/2003 J10, Chaldene, Isonoe, Erinome, Kale, Aitne, Taygete, S/2003 J9, Carme, Sponde, Megaclite, S/2003 J5, S/2003 J19, S/2003 J23, Kalyke, Kore, Pasiphae. Eukelade, S/2003 J4, Sinope, Hegemone, Aoede, Kallichore, Autonoe, Callirrhoe, Cyllene, and S/2003 J2)
  • Click here for Wolfram|Alpha data on Jupiter

* = Courtesy of Wolfram Astronomy Assistant

I’ve been an amateur astronomer all my life, and I’ve been fortunate to use some of the best non-professional astronomy packages on a variety of platforms. Two of my favorite Windows/Mac astronomy applications are Starry Night Pro 6.x and Voyager 4.x. I’ve reviewed Starry Night for several UK magazines – MacWorld and Software Latest – and Ted Bade recently reviewed the Voyager 4.5.7 software.

This afternoon I ran Starry Night on my older G5 iMac and, as always, it showed the daily events for today. There were four, so I selected the first that was of Europa in transition around Jupiter. I liked it well enough to take a moment to grab an image so I could share it with you readers. Jupiter is my second favorite planet in the solar system, not because of the size but because of turbulent gases that make up the atmosphere and the many moons that surround it. Europa, Ganymede, Callisto, Io, and a bunch more.

Jupiter as Seen with Software

Europa transitions Jupiter - 10-16-2010

The shadow of tiny Europa on Jupiter

After seeing the shadow of tiny Europa on Jupiter, it might be a good idea to see how Jupiter appears to someone on Europa:

Jupiter as it appears from Io, the closest of the large moons of Jupiter:

Finally, Jupiter as it is seen on Ganymede:

It is so easy to change viewing locations in Starry Night. Just use the Options/Viewing Locations menu option and select the location to use for home, then press the Go to Location button. Simple.

Now an image of Jupiter while in Starry Night’s Spaceship mode (a fun way to play space explorer), on course for Jupiter:

The keyboard shortcuts are in the upper left area of the screen, while speed/distance/acceleration are by your target. I tried the Captain Sheridan thing (diving into the Jupiter atmosphere like he did to avoid the Shadow ship in ‘Messages from Earth’ Season 3 of Babylon 5), but hitting the atmosphere of Jupiter just puts you on the other side. Bummer! I should also add that some of the shortcuts (Roll, Pitch, and Yaw) don’t do me a lot of good on my Macbook, but I still love this feature of Starry Night.

Starry Night always makes my top 10 list for students of any age, and I can’t wait until they release the next major update. Please take the time to look over the various versions of this software at the website of Imaginova. And also take time to check out Carina Software’s site – the company that developed Voyager. Carina’s mobile versions of their products were known as Carina Mobile, but are now known as SkySafari and SkyFi and are available here.

Jupiter Moons as Seen by Probes

1. IO

Check out the coolest picture ever taken from a Earth vessel: an erupting volcano on distant Io:

Image courtesy NASA

This is a new image of IO shows incredible surface details. I find it as impressive as the erupting volcano image above.

Image courtesy NASA

2. Europa – from ZDNet 5/16/2011

Europa’s surface does not look inviting, at least if one planned to explore it on foot.

Image courtesy NASA

3. Ganymede – from ZDNet 5-16-2011

When I was young, I read Robert Heinlein’s ‘Farmer in the Sky’, a novel about humanity colonizing Ganymede. Heinlein didn’t have the images and scientific knowledge we possess of Jupiter today, but he wrote an interesting tale how we might live there.  This is an image taken on the last Jupiter mission by Galileo.

Image courtesy NASA.

4. Callisto – from ZDNet 5/16/2011

The surface of Callisto appears as inviting as that of our moon, however the view of nearby Jupiter would be impressive.

Image courtesy NASA

Astronomy is interesting, and while it is fun to catch shows on the science channel, the computer is the ideal media to really get into the subject. There are a number of good open source astronomy packages like Celestina and WorldWideTelescope.org that are available for cash-strapped people that are interested but unable to afford the cash outlay for more software.

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Updates

6-24-2011 – Added Orbital Period, Average Distance from Earth information.

5-16-2011 – Added 3 new images of Jupiter moons taken by Galileo.

2-14-2011  – Added names of all moons.

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And for something completely different…

On an aside, I first tried the Starry Night software because my favorite painting of all time is Van Gogh’s Starry Night, which was the inspiration for Don McLean’s song called “Vincent”, which can be seen below:

Take care and be well.
Mike