Mariner 9

Fifty years ago this day, Mariner 9 became the first spacecraft to orbit another planet. Mariner 9 arrived at Mars after a 167-day flight on November 14, 1971. When it arrived, a global dust storm was raging on the planet, so it had to wait out the storm before any useful pictures could be taken. During its orbital tour of duty, Mariner 9 returned 54 gigabits of information to eager scientists on Earth, including 7,329 images of the red planet and its moons.

Mariner 9 was powered by 14,742 solar cells on four solar panels. The solar panels generated 500W of power while the spacecraft orbited Mars. A 20 amp-hour nickel cadmium battery stored the energy produced by the solar panels. The onboard computer had just 2K of memory (long before the days of “bloatware”), and an onboard digital reel-to-reel tape recorder was used to store data for later radio broadcast back to Earth.

Mariner 9’s mission to Mars ended on October 27, 1972 when it ran out of nitrogen gas for the attitude control jets. Mariner 9 remains in orbit around Mars, and is expected to burn up in the Martian atmosphere no sooner than the year 2022.

Broken Eyeglass Case – Again

I have yet to find a hard shell eyeglass case with a hinge that doesn’t fail in short order.

No matter how careful you are with opening and closing the case, with daily use the hinge of every hard shell eyeglass case I have ever used will suddenly fail after less than a year of use, and the eyeglass case will no longer stay closed.

Why doesn’t anyone make a spring-loaded eyeglass case hinge that lasts?

If it is impossible to manufacture a durable spring-loaded hinge, then perhaps a magnetic closure should also be added to the case.

Seth Barnes Nicholson

American astronomer Seth Barnes Nicholson was born 130 years ago this day in Springfield, Illinois on November 12, 1891. He attended Drake University in Des Moines from 1908-1912, receiving a B.S. degree in physics (with an astronomy emphasis) in 1912. At Drake, Nicholson was inspired to pursue a career in astronomy by Prof. D. W. Morehouse (then astronomy professor and later president of Drake University). He went on to obtain a Ph.D. in astronomy at the University of California in 1915.

Even though Nicholson died in 1963, he held the distinction until the year 2000 of discovering more moons of Jupiter than anyone since Galileo. Both men discovered four satellites each. Their record has now been surpassed. Graduate student Scott Sheppard and his colleagues at the University of Hawaii discovered 10 new moons of Jupiter in 2000 using an 88-inch telescope and a sensitive CCD camera atop Mauna Kea in Hawaii. Jupiter is now known to harbor 79 moons.

While at Drake, undergraduates Seth Nicholson and his wife-to-be Alma Stotts calculated the orbit of an asteroid discovered by Joel Metcalf in 1909. In those days before electronic computers, the privilege of naming an asteroid usually went not to the discoverer but to the person calculating its orbit! So, in 1911, the asteroid became known as 694 Ekard—which is “Drake” spelled backwards. One wonders why they didn’t choose the name Drake, because not until 2001 was an asteroid given that name. 9022 Drake was discovered in 1988 by Carolyn & Eugene Shoemaker and it is named after Michael J. Drake (1946-2011). Discovered just a year later—though numbered earlier (requires an accurate orbit)—and receiving a name only in 2015, asteroid 4772 Frankdrake is named after SETI pioneer Frank Drake (1930-).

Double Star Discovery: TYC 724-273-1

On 20 Oct 2021 UT, I observed the star TYC 724-273-1 in the constellation Orion being covered up by the asteroid 444 Gyptis. The star disappeared at 5:31:53.856 UT and reappeared at 5:32:10.506, a duration of 16.65 seconds.

The published apparent visual magnitude of this star is 11.5 and the published apparent visual magnitude of 444 Gyptis at the time of the event is 12.5.

The combined magnitude (mc) of star + asteroid just before (and after) the occultation event is given by

m_{c}=m_{o}-2.5\log_{10}\left (10^{0.4(m_{o}-m_{*})}+1  \right )

where mo is the magnitude of the asteroid
     and m* is the magnitude of the star

This gives us a combined magnitude of 11.14 just before the occultation.

While the asteroid is covering up the star, you should only see the asteroid, so the magnitude should decrease from 11.14 to 12.5, a magnitude drop of 1.36 magnitudes.

Much to my surprise, I observed a magnitude drop of only 0.54.

Is it possible that 444 Gyptis only covered up one component of a previously undiscovered double star? That idea is bolstered by the fact that the event occurred 14.8 seconds earlier than predicted, a full 3.7σ early.

Entertaining the double-star idea, our task is to determine the magnitudes of the two blended stars and which one got covered up. Let us call the magnitudes of the two components m*1 and m*2, with m*1 being the component that got covered. We already know that m*1 + m*2 must equal m* = 11.5. We also know that the observed magnitude drop of the m*1 plus the unobserved magnitude drop that the m*2 star would have had must equal the expected magnitude drop of 1.36. This gives us enough information to calculate m*1 and m*2 individually.

m_{*1} = -\log_{10}\left (10^{-\left (m_{c}+\Delta m_{obs}  \right )/2.5}-10^{-0.4m_{o}}  \right )/0.4

m_{*2} = -\log_{10}\left (10^{-\left (m_{*}/2.5\right )}-10^{-0.4m_{*1}}  \right )/0.4

where mo is the magnitude of the asteroid
     and m* is the magnitude of the star
     and mc is the magnitude of the star + asteroid
     and m*1 is the magnitude of the occulted star component
     and m*2 is the magnitude of the unocculted star component
     and Δmobs is the observed magnitude drop

This gives us a magnitude of 12.36 for the occulted component and 12.15 for the unocculted component. Thus we can see that I observed the fainter component of the double star being occulted by asteroid 444 Gyptis.

Finally, we can do an extra check to make sure that the magnitudes of the two star components plus the asteroid equals the combined magnitude of 11.14 we expected right before the occultation occurred.

m_{c}=-2.5\log_{10}\left (10^{-0.4m_{*1}}+10^{-0.4m_{*2}}+10^{-0.4m_{o}}  \right )

Here’s a little SAS program I wrote to do the calculations.

data magdrop;
   format mstar mastr mcomb pdelm odelm mstr1 mstr2 mtot 5.2;
   mstar = 11.5;
   mastr = 12.5;
   odelm = 0.54;
   x = 0.4*(mastr - mstar);
   mcomb = mastr - 2.5*log10(10**x + 1);
   pdelm = mastr - mcomb;
   mstr1 = log10(10**((mcomb+odelm)/-2.5) - 10**(-0.4*mastr))/-0.4;
   mstr2 = log10(10**(mstar/-2.5) - 10**(-0.4*mstr1))/-0.4;
   mtot = -2.5*log10(10**(-0.4*mstr1)+10**(-0.4*mstr2)+10**(-0.4*mastr));
   file print;
   put 'Published Magnitude of Occulted Star = ' mstar;
   put 'Magnitude of Asteroid = ' mastr;
   put 'Combined Magnitude Right Before Occultation = ' mcomb;
   put 'Predicted Magnitude Drop = ' pdelm;
   put 'Observed Magnitude Drop = ' odelm;
   if (odelm/pdelm > 0.5 and mstr1 > mstr2) or
      (odelm/pdelm < 0.5 and mstr1 < mstr2) then do;
      put 'Magnitude of Star Component Occulted = ' mstr2;
      put 'Magnitude of Star Component Not Occulted = ' mstr1;
   else do;
      put 'Magnitude of Star Component Occulted = ' mstr1;
      put 'Magnitude of Star Component Not Occulted = ' mstr2;
   put 'Total Magnitude of Both Star Components + Asteroid = ' mtot;

Published Magnitude of Occulted Star = 11.50                                                      
Magnitude of Asteroid = 12.50                                                                     
Combined Magnitude Right Before Occultation = 11.14                                               
Predicted Magnitude Drop = 1.36                                                                   
Observed Magnitude Drop = 0.54                                                                    
Magnitude of Star Component Occulted = 12.36                                                      
Magnitude of Star Component Not Occulted = 12.15                                                  
Total Magnitude of Both Star Components + Asteroid = 11.14

Clear and Present Danger

I’m far from a conservative and if you want to put a label on me it would be “progressive humanist” but I highly recommend you watch this 17-minute interview with conservative Max Boot by Walter Isaacson on Amanpour & Company from yesterday:

Donald Trump, his enablers, sycophants, and truculent supporters, are a clear and present danger to the United States. In their support of demagogue Trump, almost half of the people in this country (the almost-half that counts) have clearly demonstrated that they would unwittingly vote to elect someone far more dangerous as long as he or she pushes all the right emotional buttons.

As Mark Twain once said, “It’s easier to fool people than to convince them that they have been fooled.”

Almost as disturbing is the insouciant multitude who do not vote. About 33% of eligible voters did not participate in the 2020 presidential election.

Progressives like Bernie Sanders and Alexandria Ocasio-Cortez are recent examples in a long line of politicians and scholars who offer bold new solutions to seemingly intractable problems—certainly worthy of reasoned consideration and discussion—but at least since the election of Ronald Reagan in 1980, the right-wing attack machine has vilified progressives as “communists” or worse. A large segment of our population has been lied to for so long that they now accept these untruths as fact.

In light of the many serious problems that beset us and a political landscape utterly incapable of addressing any of them, I am seriously reconsidering my encore career during these semi-retirement years. I had always assumed that I would spend most of my time and energy continuing what I did in my spare time during my full-time-employment years: providing observational astronomy programs for the public, teaching astronomy classes, and writing about astronomy. As much as I love astronomy, I am beginning to realize that focusing almost exclusively on astronomy is not the best use of my time and energy, given the various existential crises we all face at this moment in human history. I need to be an active participant in the solutions to these problems rather than yet another distracted bystander.

How many of you have reached your retirement years and found—unexpectedly—that the hobbies and avocations that sustained you throughout your working years are not what you want to focus on now?

Most of my adult life, I’ve wanted to live somewhere where the night sky is not compromised by light pollution—especially in retirement. But the election of Trump in 2016, his almost-reelection in 2020, and the continuing “Stop the Steal” movement has been a game-changer for me. Despite my desires, the reality is that almost all of the rural areas in this country are dominated by Trump-supporters. I currently live in a semi-rural community in Wisconsin where 24% more voted for Biden than voted for Trump in the 2020 election. And, even here, we are still being besieged by Trump flags, Trump-Pence signs, and hand-written yard signs with angry missives. During the worst of the pandemic, some businesses here (including at least one restaurant) defied the statewide mask mandate with no consequences, the Republican-controlled state legislature has gerrymandered their way to an unassailable majority in a state with an electorate that is close to 50-50 between the two parties, and the 2020 election results continue to be litigated and investigated. I’m done with this place. From here on out, I’m not going to live anywhere where Biden had less than a 24% lead over Trump in the 2020 election. In searching for that place, I have found the following tool from the New York Times to be quite helpful.

Now, I want to live somewhere with lots of progressives and real opportunities to collaborate and help facilitate meaningful change that will benefit all people. That will no longer be a rural area. Elections have consequences.

Speed Warning Function

Why don’t all our cars have a speed warning function? On the highway, I usually try to maintain a speed between the speed limit and five miles per hour over (never more than that), and I’d like to have a button on my steering wheel that I can push (like cruise control) at any particular speed so that if that speed is exceeded, I get a soft audible “beep” every few seconds until my speed has fallen below the set point.

And, like cruise control (which I never use anymore for safety reasons), you would be able to change the set point as often as you like while driving.

Having this speed warning function would improve safety because you’d be less likely to inadvertently drive too fast, and you wouldn’t have to take your eyes off the road as often to look at the speedometer.

I can’t understand why this isn’t standard equipment on all motor vehicles.

Twin Suns of Different Mothers

HIP 56948 (HD 101364)—an 8.7 magnitude star in Draco—is more like our Sun than any other star yet discovered. It is 194 light years away and located at α2000 = 11h 40m 28s and δ2000 = +69° 00′ 31″, near Gianfar (λ Draconis) and the Draco-Ursa Major border, above the Big Dipper’s bowl.

Solar twin HIP 56948 (circled) in Draco near Gianfar

With the exception of lithium, the elemental abundances are identical to that found in the Sun, within the observational uncertainties. As expected, lithium is severely depleted in HIP 56948, but not as much as in the Sun. This is to be expected for a solar twin about 1 Gyr younger than the Sun.

The temperature, luminosity, mass, and rotation of HIP 56948 almost exactly match that of the Sun. For example, HIP 56948 is only 17 ± 7 K hotter than the Sun, and its mass is 1.02 ± 0.02 M. Given all these similarities, it appears its most recently determined (1993) spectral type of G5 is incorrect. Or is it the spectral type of our Sun that is wrong (G2V)? Actually, it is quite difficult to make measurements of our Sun “as a star” because it is so incredibly close and bright.

HIP 56948 harbors no giant planets or “hot Jupiters” within or interior to its habitable zone, so there remains the enticing possibility that it may host a planetary system similar to our own, though no planets have yet been detected.

Incidentally, the next time you’ve got a good view of the Head of Draco and the “box” of Cepheus, cast your eyes toward a point halfway between the two. You’re looking towards where the rotational axis of the Sun points north. Like HIP 56948, it’s in Draco.

North Solar Pole in relation to HIP 56948

“The remarkable solar twin HIP 56948: a prime target in the quest
for other Earths”
J. Meléndez, et. al., A&A 543, A29 (2012)

Television à la carte

I don’t have much time for television. Seldom more than 2-3 hours per week, most or all of it on PBS Wisconsin. I usually watch Washington Week, Here and Now (Wisconsin news), and Amanpour & Company each Friday evening, and quite a few of the Nova episodes.

Once or twice most Friday and Saturday evenings, we’ll flip through the broadcast television channels we are able to receive from Madison some 39 miles to the east, and if we’re unusually lucky we’ll happen upon something worth watching. Usually not. And then there’s the damned commercials. I’m sure wherever you are you’ll find as I do that at any given moment, most of the television stations (except for PBS) are airing commercials. Ugh!

When we travel and stay at a motel, we often flip through the cable channels they offer, and once again seldom find anything worth watching (except, perhaps, for PBS and C-SPAN), even though there are dozens and dozens of channels. Here, too, at any given moment, most of the cable channels (except for PBS and C-SPAN) are airing commercials.

I have an aversion to advertising of any kind, and will go to great lengths to avoid watching anything that is interrupted by commercials during the program. Some of you might not be old enough to remember that when cable television first came out, a big selling point was that by abandoning free broadcast television and paying for cable TV, you could watch programs free of advertising. Well, we know how long that lasted. The number of commercials we have to endure has increased dramatically since the “golden age of television” in the 1950s, 1960s, and 1970s.

In my opinion, almost all of the television stations offered on both broadcast TV and cable are garbage. I have not subscribed to cable TV since the early 1980s, and have never been a satellite TV subscriber.

The only way I would ever subscribe to any kind of television service (cable, satellite, or internet) is if I they gave customers the ability to pick and pay for only the channels you want. Television à la carte, in other words. And the list to choose from should be huge, including multiple PBS channels, documentary film channels, reputable news channels, foreign English-language channels (or at least with English subtitles), classic movie channels, and, yes, NASA TV. And, please get rid of the advertising except—if need be—in between programs. I would pay extra for this option.

I am also frustrated by not being able to watch many newly-released documentaries (or documentary series) without subscribing to a service. Why should I subscribe to a service when all I want to do is watch one program? Why not charge $12 (or whatever) for each program a person wants to watch?

There is a case to be made for “flipping through the channels” and happening upon a documentary, movie, or television program of interest that you might not discover otherwise, but until some company offers television à la carte with a wide selection, my local PBS station is going to get all of my television dollars. I am delighted that—with the advent of digital television—we now have four PBS Wisconsin television stations to choose from!

Satellites and More – 2021 #1

Edmund Weiss (1837-1917) and many astronomers since have called asteroids “vermin of the sky”, but on October 4, 1957 another “species” of sky vermin made its debut: artificial satellites.  In the process of video recording stars for possible asteroid occultations, I frequently see satellites passing through my 17 × 11 arcminute field of view.

I’ve put together a video montage of satellites I serendipitously recorded during the first half of 2021.  Many of the satellites move across the field as “dashes” because of the longer integration times I need to use for some of my asteroid occultation work. A table of these events is shown below the video. The range is the distance between observer and satellite at the time of observation. North is up and east is to the left.

North is up and east is to the left; field size 17′ x 11′

Interestingly, four of the satellites above (2, 9, 12 & 13) are in retrograde orbits, that is their orbital inclination is > 90˚ and their east-west component of motion is towards the west instead of the east. However, one of these retrograde satellites (#12) appears to be orbiting prograde. This is Japan’s GCOM W1 environmental satellite, which is in a sun-synchronous orbit. Now, if you look at the very next satellite in the list (#13) you’ll see that it has very similar orbital elements (retrograde, sun-synchronous), I observed it just 5 days later, and it appears to be orbiting retrograde as you would expect (unlike GCOM W1). This is NASA’s Aqua environmental satellite. GCOM W1 and Aqua have orbital inclinations of 98.2082˚ and 98.2090˚, respectively.

There is also a prograde-orbiting satellite (#5) that appears to be orbiting retrograde. This is OneWeb-0056, a broadband internet satellite that is part of the OneWeb constellation, a competitor to SpaceX’s Starlink satellites. Last summer, I saw this same behavior with OneWeb-0047 which has a very similar orbital inclination to OneWeb-0056 (87.5188˚ and 87.8802˚, respectively).

Apparently, satellites with orbital inclinations within a few degrees of 90˚ (polar orbit) can sometimes appear to move in the opposite sense than their orbital inclination would indicate, when seen from the ground. I suspect that it must have something to do with where the satellite is in the sky and the vector sum of the line-of-sight motion of the satellite and the Earth’s rotation, but I have not yet found an expert who can confirm this or provide another explanation.

Satellite #11 is faint and makes a brief appearance in the extreme lower right corner of the frame. If you don’t look there you’ll miss it!

There were two satellites I was unable to identify, shown in the video below. They are either classified satellites or, more likely, small pieces of space debris that only government agencies are keeping track of. Note that the first unidentifiable satellite was moving in a retrograde (westward) orbit. The second satellite could be CZ-3A satellite debris (2007-003Q), but I think it was moving too fast to be that satellite (range 3,018.9 km, perigee 511.7 km, apogee 37,523.8 km, period 671.13 minutes, inclination 24.9940˚, eccentricity 0.7287013).

Unidentifiable satellites

During this period, I recorded one geosynchronous satellite, JCSAT-3. It is no longer operational. Here is the video, followed by the satellite information, followed by the light curve. As you can see when you watch the video and look at the accompanying light curve, this satellite gradually got brighter as it crossed the tiny 17′ x 11′ field of view of the video camera. Amazing!

Geosynchronous satellite JCSAT-3 moves slowly across the field and slowly brightens
JCSAT-3 brightens as it crosses the field

Occasionally, I record other phenomena of interest. Meteors during this period are described here, and you will find a high energy particle that “zapped” the CCD chip in the middle of the following three consecutive video frames. The red circles identify a spot and a pair of spots located some distance away that “lit up” when the high energy particle hit the chip. Events like this are fairly common, but what’s unusual here is the wide separation of the two regions that lit up.

Hughes, D. W. & Marsden, B. G. 2007, J. Astron. Hist. Heritage, 10, 21

Classics by Request

One of the joys of my life right now is tuning in to “Classics by Request” on Wisconsin Public Radio each Saturday from 10 a.m. to 1 p.m. This program has been on the air at WPR since 1980, and Ruthanne Bessman has been superbly hosting the program since 1999. When Ruthanne is away, Anders Yocom fills in and he is outstanding as well.

What makes this program work is that it occurs at a convenient time for most people, is a live call-in request program, offers a web form for your request with an area for a short narrative that can be read on air, and allows you to use the web form or call in at any time in advance of the program. And, importantly, the host reads your first name and city immediately before and after each request is played.

During a lifetime of listening to classical music, I’m bursting at the seams with great music I’d like to share with others, so I’m a regular contributor to “Classics by Request” and identified on air as “David in Dodgeville”.

We should never take for granted our classical music stations. During my years in central Iowa 1970-2005, WOI-FM 90.1 in Ames was one of the best classical stations in the country. I will never forget Doug Brown, Jake Graves, Mike Gowdy, Karen Bryan, Curt Snook, Hollis Monroe, and Rachel Jeffries, and the profoundly positive effect they had on my life and my love of classical music. I fondly remember the live request program on WOI-FM where they devoted an entire evening each week (7-11 p.m.) to classical music requests and played entire works and not just excerpts. Tragically, the WOI-FM I knew and loved is no more. It was absorbed a few years ago into Iowa Public Radio and the special magic is gone. A few listeners have tried to pick up the pieces and recreate some of the magic of the original WOI-FM on KHOI-FM Community Radio 89.1.

In my opinion, every metropolitan area and geographic region should have a radio station that primarily plays classical music and has at least one “local” on-air classical music host. (Depending on a national feed for all of your music depersonalizes the experience for me and many other listeners.) Each of these stations should have a “Classics by Request” program.

To be most effective and enjoyable, a “Classics by Request” program should have the following features:

  • Air at one or more convenient times for most people (Saturday or Sunday mid-morning to early afternoon, or Monday-Thursday evenings)
  • Be long enough so that an entire work can be played in addition to movements or sections of a work
  • Web request form that includes a section for notes about the work being requested (WPR has a great example of this)
  • Offer both phone-in and web-form options during a live call-in program, and at any time before the program
  • Play any particular work no more often than once per month
  • Identify the requester on air before and after the work is played, by first name and city, unless the requester wishes to remain anonymous
  • Include relevant and accurate information about the work and composer that the requester provides, on-air
  • The requester should know when their requested work will be played (date and program)

As I prepare to move to Tucson, Arizona to be closer to family and an active classical music scene with volunteer music education and symphony support opportunities, I am disappointed to see that Arizona Public Media Classical 90.5 FM does not appear to have a call-in request program. Hopefully, I can successfully encourage them to add such a program. If not, I’d be interested in working with others to create a listener-supported classical music station in Tucson that frequently features requests, including recordings provided by listeners. I’d also like to host an on-air program each week, and I have a large classical music library to draw upon for that program.

Here is a list of U.S. classical stations that have request programs.

WFMT • Chicago, IL
Saturdays 8-9 a.m.

Interlochen Public Radio • Interlochen, MI
Saturdays 9 a.m. – noon

Illinois Public Media
Saturdays 9-11 a.m.

Wisconsin Public Radio
Saturdays 10 a.m. – 1 p.m. (noon during Metropolitan Opera season)
Plays shorter works or portions of longer works
Host: Ruthanne Bessman (sometimes Anders Yocom)

WFYI, HD2 • Indianapolis, IN
Sundays 6-7 p.m.

KHOI • Ames, IA
Mondays 8-10 a.m.
Rebroadcast Sundays 6-8 a.m.
“Paul is the one Morning Masterpieces host who will take music requests during live shows. He likes to play music by living composers, obscure works of classical music, and works that push the boundaries of ‘classical music’.”

WRTI • Philadelphia, PA
Wednesdays 12-3 p.m.

Radio Kansas • Hutchinson, KS
Fridays 9 a.m. – noon

Nebraska Public Media
Fridays 1-4 p.m.

KVNO • Omaha, NE
Fridays 2-4 p.m.

Minnesota Public Radio
Fridays 3-7 p.m.

WWNO • New Orleans, LA
Weekdays 9 a.m. – 1 p.m.

WSMC • Collegedale, TN
Southern Adventist University
Weekdays 12-1 p.m.

KUSC • Los Angeles, CA
Weekdays 3-5 p.m.

KFMA • Austin, TX
Weekdays 6-7 p.m.

WCPE • Wake Forest, NC
Fridays 9-10 p.m.
Saturdays 6 p.m. – midnight

WNED Classical • Buffalo, NY
Weekdays 7:30 a.m. – one “Off to School” request
Weekdays 5 p.m. – one “Oasis of Sanity” request

Iowa Public Radio
“On the last Friday of the month IPR Classical plays requests”
1-5 p.m.

KDFC • San Francisco, CA
“Due to the volume of requests, unfortunately, we won’t be able to let you know when your request will be played.”