Galactic Encounters: Our Majestic and Evolving Star-System From the Big Bang to Time’s End
by William Sheehan and Christopher J. Conselice

With a score of books published on the history of cosmology and research on galaxies, another one in the same general lines seems unnecessary. However with the thoroughness and interesting writing “Galactic Encounters” is sure to earn a place in your bookshelf whether you’re interested in history of science or in cosmology.

Galactic Encounters does what few similar books do – it introduces the important observers and theoreticians throughout the past few hundred years of astronomical research together with the contemporary ideas about nebulae at the ime..

Similarly to others, the book covers William Herschel’s and Edwin Hubble’s work, but not only – instead of only focusing on their research about nebulae, the authors give an idea of the astronomers lives and characters, and it does that in the case of tens of astronomers, several of whom would only briefly be mentioned in other popular accounts of the history of cosmology.

As an example one can read about Percival Lowell and his obsession with the rotation period of Venus or how and who discovered the spiral arms of our galaxy or how cosmologists came up with such ideas as dark matter and dark energy.

The book is written starting from the earliest observations and scientists and continues all the way to twenty first century. If you’ve taken a basic astronomy course at college or university level, the cosmology part will be familiar to you however one of the great benefits of reading this book is that you get an idea of how the discoveries were made – something that usually isn’t included in basic astronomy classes, but would be in specific courses on cosmology.

The book is also suitable for general readers with maybe less background in physics or astronomy, as you don’t need any mathematics to fly through the book and observations described within.

Another fascinating thing about the book is, that a chapter might start with something where you might not see a straight connection to all that came before and might wonder why there are such detours to other topics in astronomy, but they all lead back to the general story.

In short: “Galactic Encounters” is very interesting, thorough and well-illustrated.

Labels: book review, cosmology, galactic encounters

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Watch Earth roll by through the perspective of ESA astronaut Alexander Gerst in this six-minute timelapse video from space. Combining 12 500 images taken by Alexander during his six-month Blue Dot mission on the International Space Station this Ultra High Definition video shows the best our beautiful planet has to offer.

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Labels: nasa, Orion, video

Comet Lovejoy (C/2014 Q2) is brightening into naked eye visibility as it is moving into northern skies - Right now at around magnitude 6 in the constellation Columba, it is expected to increase in brightness up to fifth magnitude in the coming weeks or months and it will be moving towards northern hemisphere sky. For northern observers it will be moving from under Canis Major toward Orion and then under Taurus.

You can find it's precise location on heavens-above.com

Labels: comet, sky-watch

Biographical Encyclopedia of Astronomers

In the age of Wikipedia, the free encyclopedia and Google search, one might start to doubt the need for any other reference material, as everything seems close at hand and easily found, although sometimes it might take several pages of search results to find the real thing you’re looking for, and in case of Wikipedia, one can’t always be certain of the accuracy of the writing.

If you’re an astronomer or historian of science or are just interested in the history of astronomy and go through book after book about history of astronomy, a lot of times one might come across names that are total strangers for you – maybe the name is of an astronomer who is a famous astronomer in a small country and did some important work on a specific subject, but perhaps focused on other related fields as well – if you’d try to find information about such an astronomer online, a lot of the information would be in a different language or you can find only highlights or maybe all you can find online is someone mentioning an important fact in one book.

In case of the Biographical Encyclopedia of Astronomers I doubt that there would be many astronomers who you can’t find in there, as there are astronomers from all across the world from ancient Greek and Arabic astronomers to 20^th century well known astronomers such as Edwin Hubble and Fred Hoyle. The entries run from a few sentences to several pages long and give a basic idea about what the person worked on and their contributions to science and also about their life.

In addition to astronomers you can also find entries for telescope makers such as Peter and John Dollond and The Clark family, but also about some scientists that are better known for their contributions in physics such as Erwin Schrödinger or Robert J. Oppenheimer, but you might be surprised to find the writer Aleksandr Solzhenitsyn in this encyclopedia, but reading the short entry lets you know that later in life he taught physics and astronomy.

It is a very necessary book. The usefulness of having information about 1800 astronomers or astronomy-related people that are provided in the Biographical Encyclopedia of Astronomers can be easily seen as although you might get most important information about famous figures in astronomy even in a textbook the smaller names are often left unmentioned, but they can mostly be found in Biographical Encyclopedia of Astronomers, with the entries having been written by well-known historians of science, who a lot of times have written whole books about the person they wrote about for the encyclopedia. So if you want to know even more about someone it is quite easy to continue your research, as the entries are followed by selected references that provide more detailed information.

I quite like using this encyclopedia – for looking up another astronomer that I know nothing about and happened across while reading about the history of astronomy, but as well for opening up at a random page and finding out something new about someone who once maybe in a far distant land with totally different ideas, was looking up at the same night sky that we can see now.

Did you know that Hypsicles of Alexandria was the person who wrote a book called "On Rising Times", that was the first book to be written in Greek that used sexagesimal arithmetic and divided the ecliptic into 360 degrees of arc?

Although I was able to think of some astronomers or telescope makers that I couldn't find in this encyclopedia, they were few and far between, and mostly I could attribute their absence to them not being famous enough or not having had a great enough contribution to science.

Labels: astronomers, book review, encyclopedia

On December 6^th, 2014 NASA's New Horizons space craft awoke from its final hibernation before its encounter with Pluto in July 2015.

New Horizons will be observing a Kuiper belt object starting from January and will observe one more in June and several more after the Pluto flyby.


To find out more about the mission, watch this video:

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Japan launched its second spacecraft for an asteroid mission - Hayabusa 2 - the successor to the first Hayabusa mission that was launched in 2003 and returned to Earth in 2010 with grains of asteroid material as samples.

In the Hayabusa 2 mission, the previous missions weak spots have been overcome - the ion engine has been improved and sample collecting mechanisms have been updated.

Hayabusa 2 was launched on December 3^rd, 2014, and is expected to reach it's destination, the asteroid 1999 JU₃ in 2018 an return to Earth in 2020.

The asteroid 1999 JU₃ belongs to the Apollo asteroids class that orbit the Sun near Earth with their closest approaches to the Sun closer to the Sun than the Earth's orbit and furthest points in their orbit outside of the Earth's orbit making them potentially hazardous in astronomical timescales.

Labels: Hayabusa 2, Japan, JAXA, news, spacecraft

On December 5^th, 2014, NASA had it's first test flight of the Orion spacecraft on a Delta IV Heavy rocket from Cape Canaveral Air Force Station's Space Launch Complex.

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The Moon on 2^nd December, 2014.
The picture was taken with a Canon Eos 500D camera and a Skywatcher 1000mm focal length refractor in prime focus.

The Moon on 2nd December, 2014. Credit: Kadri Tinn

Labels: astrophoto, moon, photo

Classic Telescopes
A Guide to Collecting, Restoring, and Using Telescopes of Yesteryear
by Neil English

"Classic Telescopes" is a good introduction to historic telescope makers and their lives and creations mostly focusing on those telescope makers that also made smaller instruments that might end up in the hands of an amateur astronomer.

In the book one can get acquainted with all the best known telescope makers of the past few centuries starting with for example the Dollonds - an originally father and son firm that made spectacles and high quality achromatic telescopes the sale of which to mainland Europe was stopped during the Napoleonic wars as spyglasses served good uses in war.

In addition to Dollond, there's also mention of Joseph von Fraunhofer and Alvan Clark, but also later telescope makers and corporations such as Carl Zeiss in Jena, Germany.
Although the telescope makers are important in their own right, the book also shows what can and what is still done with old telescopes.
Although nowadays many a new amateur astronomer might aim for a large aperture and short focal length fast telescope for imaging, the book shows how long focal length slow telescopes with a famous name can still be very nice to use - maybe not for photography but visual observations of binary and multiple stars certainly.

The book is written in a quite interesting and flowing way, as in between history you can read about the restoration of some telescopes and also about some of the methods that are used and one can learn such interesting things as why some old lenses actually work better than some newer ones.

In general it was fascinating and a fast read.

Even if you're not an owner of a hundred-year-old or even older telescope or planning to buy one, this book makes for a good eye-opener as it introduces opticians and their work in a less academic way that would be appealing for a larger general audience.

Labels: book review, classic telescopes, Neil English, telescopes