Absolute Magnitude Luminates Absolutely

This week I want to discuss “What might cause the closer of two identical stars to appear dimmer than the farther one?”

Apparent Magnitude: A measurement of the brightness of stars without regard to their distance from Earth.

  • The scale in use today starts with the star Vega and an apparent magnitude of 0.0
  • Objects brighter than Vega are assigned negative numbers.  For example. Sirius, the night’s brightest star, has an apparent magnitude of -1.44
  • The scale was extended to include the dimmest stars visible through binoculars and telescopes.  For example, a pair of binoculars can see stars with an apparent magnitude of +10

Ignoring distance for a moment, all other things being equal, the closer of two identical stars will appear brighter (have a smaller apparent magnitude) to us than the more distant star.  When we account for the difference in distance, we use either or two measurements:  absolute magnitude and luminosity.

Absolute Magnitude: The brightness a star would have at a distance of ten parsecs (10 pc) or 32.6 ly. Continue reading “Absolute Magnitude Luminates Absolutely”

Autumn Arrives and Adventures in Astronomical Observing

Autumn arrived mid-week here in the Heart of America, but you wouldn’t have known it by looking at the weather forecast:  Mid 90s and moderately high humidity.  Also with the change of the seasons, I retired my FitBit Charge (or rather it retired itself by falling apart) and upgraded to a Samsung Gear Fit2.  The new fitness tracker is spurring me on to be more active, although my sleep pattern hasn’t improved much. I can safely blame work (10 pm to 4 am conference call on a Saturday night/Sunday morning) and astronomy, which requires, well, dark skies, for my reduced snooze time.

Speaking of astronomy, I’ve upgraded, finally after two years of paralysis analysis, from the Meade ETX 90, gifted to me by my father in October 2010 (also, unsurprisingly the birth of this blog site), to an Orion SkyQuest XX14G.  Continue reading “Autumn Arrives and Adventures in Astronomical Observing”

Grande Finale to a Grand Weekend

I’m amazed at how much I accomplished this past weekend, especially considering my husband had major surgery less than three weeks ago.

Friday Evening

TalkingTolkienTwoTowersFriday night was our first venture out on a ‘date’ since the surgery.  I signed up for a free lecture and screening at the National World War I Museum and Memorial entitled “Talking Tolkien: The Two Towers.”  We arrived about fifteen minutes early to enjoy some hors d’oeuvres and drinks.  We retired to the auditorium and waited a few minutes.  At ten minutes or so after the hour, the lecturer strolled up to the podium and gave a meandering introduction of upcoming events in a clear effort to stall.  He wanted to give the people in the lobby time to finish eating.

His lecture on Tolkien’s experiences during the Battle of the Somme was quite brief and rushed, not at all what I had been hoping for.  He further devolved into a montage of photographs from the Museum’s collection delivered in the manner of a television show’s “Previously on …” wrap of the Hobbit and the Fellowship of the Ring.  You could clearly see where Tolkien (and probably Peter Jackson) got his inspiration for scenes from Middle Earth and the conflict immortalized in the Lord of the Rings.   After the lecture, the screening of The Two Towers began, for which Terry and I stayed only about thirty minutes before deciding the movie viewing experience was better at home.

Once back home, I decided to break out the Celestron C8 I had recently borrowed from my astronomy club.  Despite dire predictions, the sky remained perfectly clear so I looked forward to an evening of planetary observing, since all five visible planets are ripe for the plucking at this time of year.  I got everything attached to the tripod and manhandled it outside to my lower patio, giving it a quick leveling and orientation north so I could get through a polar alignment swiftly.  Then I just had to wait for darkness to fall enough for me to see Polaris with my naked eye.  Continue reading “Grande Finale to a Grand Weekend”

Tonight’s Adventure in Star Gazing with the Public

Tonight is my first night this year as a volunteer of the Astronomical Society of Kansas City in our public outreach efforts to introduce astronomical observing to the public.  Every Saturday night in May and through the end of October, we open up Powell Observatory to the public and provide education programs, solar observing, binocular observing and of course telescopic observing (weather and cloud cover permitting).  The weather forecast for this evening couldn’t be better.  See for yourself as we have our own weather station and sky cam broadcasting 24-hours a day.

Astronomy’s Sky this Week reports for tonight:

Saturday, May 14

•  The Moon moves approximately 13° eastward relative to the starry background every 24 hours, and its motion carries it near Jupiter this evening. From North America, the two appear within 5° of each other all night. They will be in conjunction at 6 a.m. EDT tomorrow morning, when our satellite passes 2° due south of the planet. Although the best views of the pair come with the naked eye or binoculars, don’t pass up the opportunity to observe Jupiter through a telescope. The giant planet’s disk currently spans 39″ and displays a wealth of atmospheric detail. All this week, Jupiter appears high in the south as darkness falls and doesn’t set until nearly 3 a.m. local daylight time. It shines at magnitude –2.2 — brighter than any other point of light in the night sky — against the backdrop of southern Leo.

While Sky and Telescope Sky at a Glance expands on: The two brightest things in the evening sky, the Moon and Jupiter, shine high just a few degrees apart this evening, as shown here. Third brightest is Mars, low in the southeast after dark.

So for a great time this evening, head south of Kansas City down US-69 to Louisburg and join me and several hundred other people as we take in the wonders of the night sky.

Keep Looking Up!

 

 

Hubble’s high-definition panoramic view of the Andromeda Galaxy | Astronomy.com

Mega coolness!

Andromeda Galaxy Hubble Closeup
NASA/ESA/J. Dalcanton/B.F. Williams/L.C. Johnson (University of Washington)/The PHAT team/R. Gendler

Never before have astronomers been able to see individual stars inside an external spiral galaxy over such a large contiguous area.

Hubble’s high-definition panoramic view of the Andromeda Galaxy | Astronomy.com.

18.263k days or .5c yrs

MyBabyPhoto64
Me (late 1964)

Good morning!

And Happy Birthday to myself.  I’ve crossed over.  I’ve reached another dreaded milestone.  Today is the first day of my fifth decade.

To make myself feel better about this dubious event, I’ve reverted to two of my favorite past times:  math and astronomy.

I decided to calculate how many days I’ve been breathing air on Earth.  For that I had to find a date calculator.  Plugging in the relevant date (today in 1964 and 2014), the following results popped up:

From and including: Friday, October 2, 1964
To and including: Thursday, October 2, 2014
Result: 18,263 days

It is 18,263 days from the start date to the end date, end date included

Or 50 years, 1 day including the end date

Alternative time units 18,263 days can be converted to one of these units:

1,577,923,200 seconds
26,298,720 minutes
438,312 hours
18,263 days
2609 weeks

In addition, the Earth is travelling through space, via the Milky Way, at the incredible speed of 3,728.23 mps.  Roughly, the Earth has moved 5.88286061194e+12 miles since I was born, give or take a few.  That equates to approximately 63,256.57 astronomical units.  A rolling stone gathers no moss . . .

And the .5c I included in the title of this post?  No, I’m not travelling at half the speed of  light (except in my dreams).  I’m merely reflecting upon reaching my half century mark.

I decided to make a four day weekend out of this auspicious occasion so I’m relaxing at home, reading and doing other none stressful activities.  No parties (that I know of) and no surprises.  Just Terry, me and the dogs hanging out.

Just another day in the neighborhood.  Eighteen thousand two hundred sixty-three and counting.