Friday, August 27, 2021

WR 134 - A Wolf-Rayet Star with Nebulosity

Oh my gosh, what a terrible summer season for astrophotography. There was maybe 5 relatively clear nights since July 12 when I completed the tandem telescope setup. I had expected to image my favorites by now - the Trifid, the Lagoon, etc., with my new ASI2600 camera, but alas, that's probably not going to happen now as they are slowly receding in the southwest. I may have another couple of weeks to give them a try while the moon is out of the picture, but if the weather doesn't cooperate soon I may need to wait until next year. 

However, I did point my scope to an object I have never imaged before. It is well placed in the sky, high and to the SE allowing me to run long series of narrowband images throughout the entire evening. This object is WR134, a Wolf-Rayet star with surrounding nebulosity. A tough one for sure, but I wanted to give it a try. The star itself is nondescript, but because of the intense radiation it spews forth, the surrounding gas, excited by the star's radiation, glows brightly.

Wolf–Rayet stars, often abbreviated as WR stars, are a rare heterogeneous set of stars with unusual spectra showing prominent broad emission lines of ionized helium and highly ionized nitrogen or carbon. The spectra indicate very high surface enhancement of heavy elements, depletion of hydrogen, and strong stellar winds. The surface temperatures of known Wolf-Rayet stars range from 20,000 K to around 210,000 K, hotter than almost all other kinds of stars. (Wiki)

WR 134 is a variable Wolf-Rayet star located around 6,000 light years away from Earth in the constellation of Cygnus, surrounded by a faint bubble nebula blown by the intense radiation and fast wind from the star. It is five times the radius of the sun, but due to a temperature over 63,000 K it is 400,000 times as luminous as the Sun. (Wiki)

Over the nights of August 2, 3 and 6, I captured both Ha and Oiii narrowband data, 65 subs of 300 sec exposures for each, and a series of RGB subs to get the star colors correct. I had planned to get Sii data as well (to complete the standard SHO Hubble Palette) but the clouds moved in and stayed for awhile! So, with what I had, I processed a HOO palette, the results shown in the image below.

WR134 and Nebulosity (August 2021)
WO GT102 f/5.6  -  ASI2600mm Pro
65x300s Ha; 65x300s Oiii; 10x30s RGB Stars

WR134 is the brighter star in the small group of four stars at the center of the image. The enlarged central region clearly shows the star (reddish-white at center) with the bubble nebula surrounding it. The upper region of the bubble, bluish in color, is the Oiii ionized gas. 



Then, some clear skies presented themselves on and about August 25th. I had to setup and try to get the missing Sii data, which I was able to do over two evenings. I managed to get 67 subs of 300sec. I added this new data into the mix and with some re-processing of the original data with the new Sii data I created the final image using a modified SHO Hubble palette.

WR134 and Nebulosity (August 2021)
WO GT102 f/5.6  -  ASI2600mm Pro
65x300s Ha; 65x300s Oiii; 67x300s Sii; 10x30s RGB Stars

Full resolution images can be found at XCalRocketMan's Astrobin page

So, I have at least one new image to add to my collection from the 2021 summer season. Hopefully I'll capture some other deep space summer gems before they move out of view until next year.

 

Sunday, August 22, 2021

Grand Slam of Jupiter Moons

On the night of August 15, 2021, a very rare alignment of Jupiter's moons occurred. On this night a triple transit on Jupiter with the moons Callisto, Ganymede and Europa in transit was visible from some parts of the world.  After the triple transit there was very rare event when Ganymede occulted Europa followed by Ganymede eclipsing Europa!  

Although I have tried my best to capture images of the planets the seeing at my location in Maryland is usually awful - and good seeing is an absolute 'must have' in planetary imaging. This event would have been one that I would have certainly tried for, but the weather conditions (clouds, go figure) nixed that.

However, Christopher Go, one of the handful of the best amateur planetary photographers, had excellent conditions at his location in the Philippines. He was able to capture the entire series of events with his 14" Celestron SCT.

Here is the NASA Astrophoto of the Day that he was awarded.

For a more complete review of Christopher's imaging, including this event, point your browser to his web page at http://astro.christone.net


Saturday, August 14, 2021

Mars Drilling Didn't go Quite as Expected

Last week, NASA’s Perseverance rover shot for a new milestone in the search for extraterrestrial life: drilling into Mars to extract a plug of rock, which will eventually get fired back to Earth for scientists to study. Data sent to NASA scientists early on August 6 indicated a victory—the robot had indeed drilled into the red planet, and a photo even showed a dust pile around the borehole.

NASA

But, while data indicated that Perseverance had transferred a sample tube into its belly for storage, that tube was in fact empty, driving Katie Stack Morgan, deputy project scientist of the Mars 2020 mission, to call it “the case of the missing core.”

While this is not the 'hole in one' we hoped for, there is always risk with breaking new ground," Thomas Zurbuchen, associate administrator of NASA's Science Mission Directorate in Washington, said in a statement. (Perseverance's mission is the first step in a Mars sample-return campaign, which has never been done before.)

Read the full story at ARS Technica


Tuesday, August 3, 2021

Get Ready for the Perseids Meteor Shower

On the nights of August 11-13, 2021, the most famous of all annual meteor showers, the Perseids, will take place. And this year conditions are right for an optimal show, since there’ll be no moon to ruin our view.

Perseid meteors scream through our atmosphere at nearly 40 miles per second, so they often leave behind long, glowing, persistent trains. The shower gets its name from the point in the sky where the meteors appear to originate - the radiant. When the radiant is high in the sky you can capture the most meteors. As typical of most meteor showers, this occurs in the early morning hours - and this year that would be on Thursday, August 12 around 2 A.M when up to 100 meteors per hour can be seen (in dark suburban skies). Since this particular shower is so plentiful, it's possible to spot the meteors as early as 9 p.m.

Although that is the best time to view them, don't worry if you miss the peak as this shower typically builds up and winds down slowly, so you can head out on any of the few days before and after the 12th as well.

JASON WEINGART / BARCROFT MEDIA

Observing the Show

In order to achieve the best views avoid artificial light as much as possible when viewing the shower. This doesn’t necessarily mean you need to travel to a dark-sky site. Just try to keep nearby street and house lights out of your line of sight.

Pick a comfortable location where the view to the north-east is unobstructed. Lie back so that a large swath of the sky is visible and you are not straining to keep you head looking up. A lounge chair or recliner works well. Look for Perseid meteors at an altitude around 60˚ in any direction. If you want to see the most faint meteors be prepared to spend about 20-30 minutes to allow your eyes to get dark-adapted. 

Where do the Perseids come from?

Meteors are fragments of periodic comets, the dust and debris that they leave behind in their orbits. In the case of the Perseids, that comet would be Swift-Tuttle, which orbits between the Sun and beyond the orbit of Pluto once every 133 years. Every year, the Earth passes near the path of the comet, and the debris left behind by Swift-Tuttle shows up as meteors in our sky as they burn up in our atmosphere.


Soldiers Delight Star Party

Hosted by    Westminster Astronomical Society If you are local to the Baltimore, MD area and have an interest in astronomy, why not stop by ...