September 23, 2017

AstroEvent of the Week: Spotting Iridium Flares.

 An Iridium Flare graces the dusk. (Photo by Author).

Photo by Author.  

   Looking up at the dawn or dusk skies, it’s not uncommon to see a satellite brighten, flare up, and the abruptly disappear from view. What you’ve just seen is an Iridium flare, a glint of sunlight off of a refrigerator sized satellite panel. Motorola launched this series of 66 communications satellites in 1997 through 1998 and they are currently owned and operated by Iridium Communications, Inc. [Read more...]

AstroEvent: ISS All Nite!

 

The ISS as seen from STS-130. (Image Credit: NASA).

The ISS as seen from STS-130. (Image Credit: NASA).

(Editor’s Note: Due to timeliness concerns for events mentioned, we nudged next week’s astro-event up to today!)

   After a long drought, the International Space Station (ISS) returns to the nighttime skies this week. And what a return it is; starting tonight on June 23rd, the ISS enters a phase in which it is illuminated by the Sun throughout the span of its orbit. This unique event continues for four days, and sighting opportunities abound. This is only possible within a few weeks surrounding the solstice season, and does not happen again this year. Generally, the farther north or south in latitude you are, the greater the sighting opportunities; areas such as northern Maine, for example, will see the ISS on every 90 minute pass throughout the night! This also produces a dilemma for residents of the ISS, as overheating is a major concern. To offset or minimize this effect, portions of the ISS can be angled to alternately “shade” sections and automated cooling and radiating devices are installed throughout. Now is a good time to spy this celestial outpost of humanity, as its brightness rivals Venus. Spaceweather.com, Orbitron and the NASA ISS website all provide sighting guides; you can even follow @twisst on twitter for sighting ops or our humble feed @Astroguyz if you live in the US Southeast. Our favorite pick for ISS tracking is Heavens-Above, a tried and time honored favorite… let us know of your ISS sighting success stories!

The Astroword for this week is Inclination. This is one of the essential perimeters that defines an orbit of a celestial body; usually an established and agreed upon 0° degree point is set based on the primary bodies’ rotation (as is the case for objects orbiting the Earth) or orbital plane (for objects orbiting the Sun). That is, the Earth’s orbit as traced out by the ecliptic establishes zero point inclination throughout our solar system. The fact that the illumination angle of the ISS changes is a direct result of its 51.6° degree inclined orbit with respect to the Earth’s rotational equator. This relatively high inclination was chosen to be easily achievable between U.S. and Russian launch sites. In order for the shuttle or any spacecraft to reach the ISS, it must match the same magical orbital inclination of 51.6° degrees.

Astro Event of the Week; November 10th-16th; The Launch of STS-126.

One of the very few remaining shuttle launches will be occurring this week; STS-126 is scheduled to launch on November 14th at 7:55 P.M. EST (yes, another spectacular night launch!) and dock with the ISS on Day 3.

[Read more...]

Astro-event for October 6th-12th, 2008: Spot the Hubble Space Telescope!

I almost didn’t do this weeks’ event. The Hubble space telescope is in trouble. This past week, the failure of Hubble’s Control Unit- Side A has meant that the telescope is effectively crippled in space; engineers will attempt to transfer services to the Side -B backup, which hasn’t been used since the telescope was put in orbit in 1990.

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Astro Event of the Week 9-16th, 2008.

Welcome to a new weekly feature here at Astroguyz… each Monday, our goal will be to present some new and interesting celestial event that you can see from your own backyard. If the event is happening anytime from Monday evening, US East Coast time, up through early next Monday, you’ll read about it here. We’ll also tie in a vocabulary “astro-word of the week.” So, as Fat Albert says, “If you’re not careful, you just might learn something before it’s done!”

[Read more...]