In the Sky this Week – August 29, 2017
avatar

5:30 AM Aug. 29, 2017

Eastern predawn sky 5:30 AM Aug. 29, 2017. Credit: Stellarium / Bob Trembley.

The eastern sky before sunrise is getting busy! Venus is accompanied by several bright stars, and the easily recognizable constellation of Orion is higher each morning; winter stars are on their way!

Moon Saturn Conjunction Aug. 29 & 30, 2017

Moon Saturn Conjunction - Aug. 29 & 30, 2017. Credit: Stellarium / Bob Trembley.

There will be a conjunction of Saturn and the Moon in the southern sky on the nights of the 29th and 30th; the first quarter moon will be very close to Saturn, and likely wash it out a bit when observing through a telescope.

Double Star Albireo in Cygnus. Credit: Creative Commons CC BY-SA 3.0

Location of Albireo in Cygnus

Albireo (or Beta Cygni, β Cygni) in Cygnus. Credit: Stellarium / Bob Trembley.

The Constellation Cygnus is overhead after sunset, and the star Albireo, makes for a very interesting object through a small telescope. To the naked eye, Albireo appears to be a single star; in a telescope, it resolves into a beautiful gold and blue double star. Tip: If you slightly unfocus your telescope when observing Albireo, the colors will spread out, and you can see them a bit better.

Albireo Barycenter

Double Stars orbit around their center of mass - called a Barycenter. Credit: Space Engine / Bob Trembley.

It is unknown if Albireo is a true binary star, or an "optical double" - a pair of stars that appear close to each other in the sky as seen from Earth, but are different distances away. The image above is a representation of what the orbits of the Albireo binary pair would look like IF it is a true binary star; the orbital period is on the order of 100,000 years.

The Sun - HMI - Aug. 28, 2017

The Sun - Aug. 28, 2017 -
Helioseismic and Magnetic Imager (HMI). Image courtesy of NASA/SDO and the AIA, EVE, and HMI science teams. / Bob Trembley.

New sunspot group AR2673 is rotating into view on the limb of the Sun, and AR2671 has rotated out of view. SpaceWeather.com reports: "Sunspot AR2672 has a stable magnetic field that poses little threat for strong solar flares."

The Sun's Corona - Aug. 28, 2017 - Atmospheric Imaging Assembly (AIA) 211 nanometers. Image courtesy of NASA/SDO and the AIA, EVE, and HMI science teams. / Bob Trembley.

The Sun currently has several Coronal Holes - these areas expel the solar wind at speeds about twice the average; SpaceWeather.com reports that the velocity of the solar wind at the time of this writing was 327.9 km/sec.

The Sky Overhead - Aug. 29, 2017 5:30 AM

The Sky Overhead - Aug. 29, 2017 5:30 AM. Credit: Stellarium / Bob Trembley.

The Sky Overhead - Aug. 23, 2017 10 PM

The Sky Overhead - Aug. 23, 2017 10 PM. Credit: Stellarium / Bob Trembley.

The Solar System - Aug. 29, 2017

The Solar System - Aug. 29, 2017. Credit: NASA Eyes on the Solar System / Bob Trembley.

Apps used for this post:

Stellarium: a free open source planetarium app for PC/MAC/Linux.
Universe Sandbox ²: a physics-based 3D space simulator.
NASA Eyes on the Solar System: an immersive 3D solar system and space mission app - free for the PC /MAC.
Space Engine: a realistic virtual Universe you can explore on your computer - free for the PC.


This blog is made possible by contributions from visitors like yourself. PLEASE help by supporting this blog.

Get the VOF Blog via email - free!

Enter your email address to subscribe to this blog and receive notifications of new posts by email.


Leave a Reply