Shasta Astronomy Club Newsletter · Shasta Astronomy Club Newsletter October 2015 Star Party...

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October 2015Star Party Location: Mount Shasta Mine Loop Trailhead Parking Lot.

Historic Brashear telescope saved for restoration in NZ Dark Sky Reserve

A 125-year-old, 18-inch (46-cm) aperture Brashear refracting telescope with an illustrious history that has languished in storage for half a century has found a new Antipodean home. This marks the first step on the road to restoring the instrument to its former glory, destined to become the centrepiece of a public outreach Astronomy Centre near the shore of Lake Tekapo in the heart of New Zealand’s South Island.

A brief history The 46-cm diameter, 8-metre focal length achromatic doublet lens of the great refractor was made by renowned Pennsylvanian optician John Brashear (1840-1920) in the early 1890s. It was the primary instrument used by Percival Lowell for his Mars studies in 1894 at the Lowell Observatory in Arizona, until it was replaced by the 24-inch (61-cm) Alvan Clark refractor.

In 1895‐96, the 46-cm Brashear lens was fitted in a new 8-me-



Earth & Sky director Graeme Murray (in green overalls) helps with the recovery of two sections that form the 8-metre-long tube of the 125-year-old 18-inch (46-cm) Brashear telescope. When fully restored, the 7-ton instrument will sit atop a 5.4-metre high cast iron pedestal crowned by a German equatorial mount as the centrepiece of Earth & Sky’s proposed Astronomy Centre beside Lake Tekapo in the International Dark Sky Reserve at the heart of New Zealand’s South Island. Image credit: E&S. Brashear_Yaldhurst_with_Graeme_Murray_940x914.jpg

tre-long tube atop a 5.4-metre-high German equatorial mount and

pier fabricated by the illustrious Warner & Swasay Co. of Cleve-

land, Ohio (the same company that built the 36‐inch Lick and 40‐

inch Yerkes refractors) and installed in a 10‐metre diameter dome

at the Flower Observatory, owned by the University of Pennsyl-

vania. The complete instrument weighed in excess of 7 tons.

For over half a century,

the 18‐inch Brashear

refractor produced

a wealth of valu-

able research data.

Walter Leight, keen

Mars observer and

instrument maker at

Flower Observatory,

held the Brashear in

high regard. He is

documented as having

used powers of 972x

to observe planet

Saturn stating, “We

often saw things (like

numerous subdivisions

in Saturn’s rings) we

weren’t supposed

to see and we didn’t

mention them.” Walter

Haas (ALPO founder)

is also on record as

stating that the 18‐inch

gave him the best views of Saturn he’d had in any telescope.

The Flower Observatory was closed in 1954 and amalgamat-ed with the nearby Cook Observatory that was acquired by the University of Pennsylvania. It was about this time that the 18‐inch Brashear was dismantled and placed into storage. In 1962, the university was looking to establish a Southern Hemisphere

John Brashear (1840-1920), a renowned Pennsylvanian optician and instrument maker, made some highly sought after telescope lenses — the largest being the 30‐inch refractor of the Allegheny Observatory in Pennsylvania. Brashear completed the 18‐inch (45‐cm) diameter, 8‐metre focal length achromatic doublet in the early 1890s. Several subsequent observers attest to the exceptional quality of the 18-inch lens. John_Brashear_557x982.jpg



The 18-inch f/17 Brashear refractor in its late 19th century heyday at the Flower Observatory in Pennsylvania, mounted on a German equatorial fabricated by the illustrious Warner & Swasay Co. of Cleveland, Ohio — the same company that built the 36‐inch Lick and 40‐inch Yerkes refractors. Image credit: University of Pennsylvania. Brashear_Flower_Observatory_heyday_659x1024.jpg

station and entered into partnership with the University of Canter-bury at Christchurch in New Zealand. One of the fruits of this academic union was the Mount John University Observatory on the western shore of Lake Tekapo.

The Brashear arrived at Mount John in October 1963, but funds

were not forthcoming for the construction of a suitable dome and

auxilliary buildings, so the instrument (sans optics) remainded

in storage on the mountain until 1990 when it was transferred to

the Yaldhurst Museum near Christchurch. Sadly, Yaldhurst was

unable to raise enough money to build a home large enough for

the assembled telescope, so it was consigned to an outbuilding for

a further 25 years.

A brighter future

Based in Tekapo township in the shadow of Mount John is the

headquarters of Earth & Sky Ltd., an astrotourism venture that

offers stargazing tours at its two public outreach observatories at

Cowan’s Hill and atop Mount John amid the domes of the univer-

sity research facilities. The Mackenzie District’s unusual micro-

climate ensures that the region is blessed with a high proportion

of clear, exceptionally dark nights. The IDA recently declared the

area an International Dark Sky Reserve.

Earth & Sky is about to embark on the construction of an ambi-

tious Astronomy Centre, the restored Brashear telescope forming

the centrepiece of a working museum that will also feature a

collection of displays about leading NZ astronomers and the site

testing and history of Mount John.

Earth & Sky’s general manager Margaret Munro said that the Brashear was an amazing and beautiful piece of 19th-century technology. “Having this sort of equipment in the Southern Hemi-sphere is really rare. Once it’s restored it will be a big drawcard for the region and will be an important part of the theme we are creating in Tekapo around the night’s sky,” she added.

Munro said the big unknown was how much the telescope would

cost to restore, but the plan was to time the restoration so it could

be installed in the Astronomy Centre in time for its opening. Until

such time as it goes on display, the Brashear has a temporary

home at the spacious workshop of Mackenzie Electrical in the

township of Fairlie, just 30 minutes drive east of Tekapo.

The 18‐inch Brashear telescope is one of a half dozen giant

refractors known to exist in the entire Southern Hemisphere and

one of just two dating from the 19th century.



Surprising Similarities Between Spiral and Ellipti-cal Galaxies --”Implies Influence of Hidden Forces”

One of the most surprising scientific discoveries of the 20th cen-tury was that spiral galaxies, such as our own Milky Way, rotate much faster than expected, powered by an extra gravitational force of invisible ‘dark matter’. Since this discovery 40 years ago, we have learned this mysterious substance, which is proba-bly an exotic elementary particle, makes up about 85 per cent of the mass in the known Universe, leaving only 15 per cent to be

the ordinary stuff encountered in our everyday lives.

Dark matter is central to our understanding of how galaxies form and evolve and is ultimately one of the reasons for the existence of life on Earth – yet we know almost nothing about it.

Surprising gravitational similarities between spiral and elliptical galaxies were discovered this past May by an international team, implying the influence of hidden forces. In the first such survey to capture large numbers of these galaxies, researchers have mapped out the motions of stars in the outer parts of elliptical galaxies



using the world’s largest optical telescope at W M Keck Observa-tory in Hawaii.

“By combining Keck telescope time from Swinburne and the University of California, we were able to investigate a larger number of galaxies which allowed us to make this important discovery,” Swinburne’s Professor Duncan Forbes said.

The team, led by Michele Cappellari from the University of Ox-ford, used the powerful DEIMOS (DEep Imaging and Multi-Ob-ject Spectrograph) to conduct a major survey of nearby galaxies called SLUGGS, which mapped out the speeds of their stars. The scientists used Newton’s law of gravity to translate these speed measurements into the amounts of matter distributed within the galaxies.

“One of the surprising findings of this study was that spiral galax-ies maintain a remarkably constant rotation speed throughout their disks,” Dr Cappellari said. “This means stars and dark mat-ter conspire to redistribute themselves to produce this effect, with stars dominating in the inner regions of the galaxies, and a gradual shift in the outer regions to dark matter dominance.”

The image below illus-trates speeds of stars on circular orbits have been measured around both spi-ral and elliptical galaxies. Without dark matter, the speeds should decrease with distance from the galaxy, at different rates for the two galaxy types.

Instead, the dark matter appears to conspire to keep the speeds steady. (M. Cappellari and the Sloan Digital Sky Survey.

But the ‘conspiracy’ does not come out naturally from the mod-els, and some fine-tuning is required to explain the observations. For this reason, some astronomers have suggested that, rather than being due to dark matter, it may be due to Newton’s law of gravity becoming progressively less accurate at large distances.

Remarkably, decades after it was proposed, this alternative theory (without dark matter) still could not be conclusively ruled out.

Spiral galaxies constitute less than half of the stellar mass in the Universe, which is dominated by elliptical and lenticular galaxies. These have puffier configurations of stars and lack the flat disks of gas that spiral galaxies have. Until now it has been technically difficult to measure the masses of elliptical galaxies



and to find out how much dark matter they have, and how this is distributed.

Because elliptical galaxies have different shapes and formation histories than spiral galaxies, the newly discovered conspiracy is even more profound and will lead experts in dark matter and galaxy formation to think carefully about what has happened in the ‘dark sector’ of the Universe.

The galaxy, NGC 7049 shown at the top of the page, is a giant galaxy on the border between spiral and elliptical galaxies that spans about 150,000 light-years. It is located about 100 million light-years away from Earth in the southern constellation of Indus. NGC 7049 is the “brightest” galaxy of the Indus Triplet of galaxies (NGC 7029, NGC 7041, NGC 7049), and its structure might have arisen from several recent galaxy collisions.

Bright Cluster Galaxies are among the most massive galaxies in the universe and are also the oldest. They provide astronomers the opportunity of studying the many globular clusters contained within them. NGC 7049 has far fewer such clusters than other similar giant galaxies in very big, rich groups. This indicates to astronomers how the surrounding environment influenced the formation of galaxy halos in the early Universe.

The globular clusters in NGC 7049 are seen as the sprinkling of small faint points of light in the galaxy’s halo. The halo – the ghostly region of diffuse light surrounding the galaxy – is composed of myriads of individual stars and provides a luminous background to the remarkable swirling ring of dust lanes sur-rounding NGC 7049′s core.

NGC 7049′s striking appearance is primarily due to this unusual-ly prominent dust ring, seen mostly in silhouette. The opaque ring is much darker than the millions of bright stars glowing behind it. Generally these dust lanes are seen in much younger galaxies with active star forming regions. Not visible in this image is an unusual central polar ring of gas circling out of the plane near the galaxy’s center.

The image was taken by the Advanced Camera for Surveys on the Hubble Space Telescope, which is optimized to hunt for galaxies and galaxy clusters in the remote and ancient Universe, at a time when our cosmos was very young.

The study was published in The Astrophysical Journal Letters.



NASA can’t use the Curiosity rover to examine water on Mars because of contamination fears

NASA proudly announced earlier this week that it had uncovered

the strongest evidence yet that liquid water flows intermittently

on present-day Mars. Using an image on the Mars Reconnais-

sance Orbiter, the space agency was able todiscover chemical

evidence of liquid water on the Red Planet.

While researchers from the space agency are confident in their

discovery, further investigation will be required to completely

validate the theory. As NASA’s Curiosity rover has been explor-

ing just 50km from one of the sites in question, it seems logical

the space agency would redirect

its path to examine the area.

Only, it’s not that simple.

First and foremost, every

country on Earth is required to

follow conditions detailed in

the 1967 Outer Space Treaty,

which places restrictions on the

actions space agencies can per-

form while exploring foreign

planets.

“States Parties to the Treaty

shall pursue studies of outer space, including the moon and other

celestial bodies, and conduct exploration of them so as to avoid

their harmful contamination and also adverse changes in the envi-

ronment of the Earth resulting from the introduction of extrater-

restrial matter,” stipulates article IX of the Treaty.

As the Curiosity rover may still be carrying some bacteria from

its 563 million kilometre journey from Earth to Mars, it does not

meet the standards of sanitation required to enter the area where

water has been found.

Director of planetary science at NASA headquarters Jim Green

is pushing for the Curiosity rover to enter the sites, claiming the

intense radiation environment found on Mars would have killed

any bugs on the lander.

However, a recent report from the US National Academy of Sci-

ences and the European Science Foundation refutes these claims

suggesting the opposite might be true.

“Although the flux of ultraviolet radiation within the Martian

atmosphere would be deleterious to most airborne microbes and

spores, dust could attenuate this radiation and enhance microbial



viability,” stated the report.

Andrew Coates of University College London’s Mullard space

science laboratory said he expected there to be heated discussion

over the idea in coming weeks.

“Curiosity now has the chance, for example, to do some closer

up, but still remote, measurements, using the ChemCam instru-

ment with lasers, to look at composition,” he told The Guardian.

“I understand there is increasing pressure from the science side to

allow that, given this new discovery.”

In addition to contamination fears, there is the logistic issues

NASA would encounter sending the rover to examine the sites.

Limitations in the Curiosity rover’s design mean it is only capa-

ble of travelling 200m per day and it can only roll over obstacles

up to 65cm high.

This means without encountering any obstacles it would take the

rover one year to reach its destination, which is time that could be

better spent elsewhere.



The Shasta Astronomy Club Newsletter is always looking for articles, photos and suggestions from our readers. If you have a story to tell about your adventures in amateur astronomy or a quick tip that needs to be shared, go ahead and send it to us at the following email address –

[email protected]

Articles can be in MS Word, Rich Text, PDF, or Plain Text. We can also cut and paste directly from an email.

Photos can be in JPG, PNG, PSD, GIF or various other graphic formats. Note, due to copyright issues we can only accept original photos.

October 2015Sunday Monday Tuesday Wednesday Thursday Friday Saturday

1 2 3

4 5 6 7 8 9 10Star PartyWhiskeytown Lake7pm

11 12 13APL Charter School Open House6-9pm

14 15 16 17Earth Science DayTurtle Bay11am - 3pm

Star PartyBrandy creek Parking Lot B6pm

18 19 20 21 22 23 24

25 26 27 28 29 30 31Club BreakfastHumble Joe’s8am

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