David Pratten is passionate about leading IT-related change projects for social good.
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PMO Setup for the First-Time PMO Leader (Part 1)

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Setting up a PMO for the first time? No project management experience? Learn how you can "wow" them in 100 days! In Part 1, the author explores ways you can become a PMO leader, skills you need for the role and the mindset you need to apply immediately.
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drpratten
13 hours ago
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Sydney, Australia
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Falling water

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drpratten
3 days ago
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Sydney, Australia
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Distance & Speed Of Sun’s Orbit Around Galactic Centre Measured

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In 2013, the European Space Agency deployed the long-awaited Gaia space observatory. As one of a handful of next-generation space observatories that will be going up before the end of the decade, this mission has spent the past few years cataloging over a billion astronomical objects. Using this data, astronomers and astrophysicists hope to create the largest and most precise 3D map of the Milky Way to date.

Though it is almost to the end of its mission, much of its earliest information is still bearing fruit. For example, using the mission’s initial data release, a team of astrophysicists from the University of Toronto managed to calculate the speed at which the Sun orbits the Milky Way. From this, they were able to obtain a precise distance estimate between our Sun and the center of the galaxy for the first time.

For some time, astronomers have been unsure as to exactly how are far our Solar System is from the center of our galaxy. Much of this has to do with the fact that it is impossible to view it directly, due to a combination of factors (i.e. perspective, the size of our galaxy, and visibility barriers). As a result, since the year 2000, official estimates have varied between 7.2 and 8.8 kiloparsecs (~23,483 to 28,700 light years).

Astronomy Image Gallery

Infrared image from Spitzer Space Telescope, showing the stars at the center of the Milky Way Galaxy. Credit: NASA/JPL-Caltech/S. Stolovy (SSC/Caltech)

For the sake of their study, the team – which was led by Jason Hunt, a Dunlap Fellow at the Dunlap Institute for Astronomy & Astrophysics at the University of Toronto – combined Gaia’s initial release with data from the RAdial Velocity Experiment (RAVE). This survey, which conducted between 2003 and 2013 by the Australian Astronomical Observatory (AAO), measured the positions, distances, radial velocities and spectra of 500,000 stars.

Over 200,000 of these stars were also observed by Gaia and information on them was included in its initial data release. As they explain in their study, which was published in the Journal of Astrophysical Letters in November 2016, they used this to examined the speeds at which these stars orbit the center of the galaxy (relative to the Sun), and in the process discovered that there was an apparent distribution in their relative velocities.

In short, our Sun moves around the center of the Milky Way at a speed of 240 km/s (149 mi/s), or 864,000 km/h (536,865 mph). Naturally, some of the more than 200,000 candidates were moving faster or slower. But for some, there was no apparent angular momentum, which they attributed to these stars being scattering onto “chaotic, halo-type orbits when they pass through the Galactic nucleus”.

As Hunt explained in Dunlap Institute press release:

“Stars with very close to zero angular momentum would have plunged towards the Galactic center where they would be strongly affected by the extreme gravitational forces present there. This would scatter them into chaotic orbits taking them far above the Galactic plane and away from the Solar neighbourhood… By measuring the velocity with which nearby stars rotate around our Galaxy with respect to the Sun, we can observe a lack of stars with a specific negative relative velocity. And because we know this dip corresponds to 0 km/sec, it tells us, in turn, how fast we are moving.”

Detection of an unusually bright X-Ray flare from Sagittarius A*, a supermassive black hole in the center of the Milky Way galaxy. Credit: NASA/CXC/Stanford/I. Zhuravleva et al.

The next step was to combine this information with proper motion calculations of Sagittarius A* – the supermassive black hole believed to be at the center of our galaxy. After correcting for its motion relative to background objects, they were able to effectively triangulate the Earth’s distance from the center of the galaxy. From this, they derived a refined distance of estimate of 7.6 to 8.2 kpc – which works out to about 24,788 to 26,745 light years.

This study builds upon previous work conducted by the study’s co-authors – Prof. Ray Calberg, the current chair of the Department of Astronomy & Astrophysics at the University of Toronto. Years ago, he and Prof. Kimmo Innanen of the Department of Physics and Astronomy at York University conducted a similar study using radial velocity measurement from 400 of the Milky Way’s stars.

But by incorporating data from the Gaia observatory, the UofT team was able to obtain a much more comprehensive data set and narrow the distance to galactic center by a significant amount. And this was based on only the initial data released by the Gaia mission. Looking ahead, Hunt anticipates that further data releases will allow his team and other astronomers to refine their calculations even more.

“Gaia’s final release in late 2017 should enable us to increase the precision of our measurement of the Sun’s velocity to within approximately one km/sec,” he said, “which in turn will significantly increase the accuracy of our measurement of our distance from the Galactic center.”

As more next-generation space telescopes and observatories are deployed, we can expect them to provide us with a wealth of new information about our Universe. And from this, we can expect that astronomers and astrophysicists will begin to shine the light on a number of unresolved cosmological questions.

Further Reading: University of Toronto, The Astrophysical Journal Letters

The post Distance & Speed Of Sun’s Orbit Around Galactic Centre Measured appeared first on Universe Today.

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drpratten
5 days ago
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Sydney, Australia
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If you like 11Foot8 bridge, you'll love 10Foot6 bridge

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If the mayhem caused by 11Foot8 bridge was not enough, imagine shaving another 1Foot2 off the clearance, et voila! The 10Foot6 Bridge in Westwood, Massachusetts. (more…)

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drpratten
6 days ago
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Sydney, Australia
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Book review: The DevOps Handbook

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9781942788003-200x300Gene Kim, Jez Humble, Patrick Debois and John Willis are the authors of the book The DevOps Handbook. how to create world-class agility, reliability, & security in technology organizations. If you look at the cover you see some similarities with The Phoenix Project. A novel about IT, DevOps, and helping your business win. And that is not a coincidence because Gene Kim is one of the co-authors of this book too.

Where The Phoenix Project is a business novel explaining the journey to set up a DevOps team, this book gives you the theoretical background, and the tools to build and use the DevOps philosophy by integrating product management, development, QA, IT operations, and information security to elevate your company.

The book is divided into four blocks: The first block (part I) introduces the three ways: The principles of flow, feedback and continual learning and experimentation. The second block (part II) explains where to start a DevOps movement in your organization. The third block (parts III-V) describes the technical practices of the three ways. The last block (part VI) discusses the technological practices of integrating information security, change management, and compliance.

In part II we see what it means to select the value streams with the most sympathetic and innovative groups to start with the DevOps transformation, analyse those value streams by creating a value stream map, and design the organization (functional, matrix or market oriented), fund services and products and not projects and create loosely-coupled architecture to dramatically improve the outcomes.

The first way describes the architecture and principles that enable the fast flow of work from left to right, from Dev to Ops to deliver quickly and safely, value to customers. Start with a single repository of truth for the entire system, make infrastructure easier to rebuild than to repair, enable fast and reliable continuous integration and automated testing and start with low-risk releases. Include running in production-like environments in your DoD.

The second way addresses the reciprocal fast and constant feedback from right to left by implementing feedback loops and use shared goals spanning Dev and Ops to improve the health of the entire value stream. The authors provide insights in telemetry from processes, behaviour and production issues, audit issues and security breaches that enables seeing and solving problems. Next we see, how we can integrate user research and feedback, peer reviews and pair programming and what it means when integrating hypothesis-driven development and A/B testing into our daily work?

The third way helps to create a culture of learning and experimentation. What can you learn from incidents, and how others can learn from your own learning by creating repositories and sharing learnings. How can you enable and inject learning into daily work by establishing a learning culture, have post-mortem meetings after accidents occur and communicate them, decreasing incident tolerances and organize game days to rehearse failures? And make sure you capture organizational knowledge by using e.g. chat rooms and chat bots.

In the last part, the three ways are extended by using them to achieve information security goals by making security a part of everyone’s job, by integrating preventive controls into a repository, by integrating security with the deployment pipeline, and integrating deployment activities with the change approval processes and reducing reliance on separating of duty.

Conclusion

If you want to start a DevOps movement, start with The Phoenix Project to make yourself enthusiastic about DevOps and continue with this book to get the real technical practices to make your DevOps a success. When buying this book, you will get a unique one-time access code to the DevOps X-ray individual assessment to benchmark your own performance against industry-wide data.

To buy: The DevOps Handbook






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drpratten
6 days ago
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Sydney, Australia
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2017 Pulse of Profession

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Project success rates have climbed and waste has fallen significantly as more organizations develop technical and leadership skills, establish project management offices to align vision with execution, and adopt agile approaches, according to Project Management Institute's latest Pulse of the Profession report.
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drpratten
9 days ago
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Sydney, Australia
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