Talk:Solar Dynamics Observatory

Launch attempts

I was thinking that this section is not really unique to the SDO and doesn't add anything to its story. In th interests of conciseness and relevance, could we leave it out?Wodawik (talk) 07:26, 13 February 2010 (UTC)

Disclosure

The original author of this page, Teridon, works for the SDO project. Some of the information this page is not publically published; it comes from internal (though not private) documentation. Therefore Wikipedia's standard for verifiability may not be met at this point. For example, the SDO mission website has not been revised recently, and does not reflect the latest orbit information (currently, the website shows that the orbit has not been decided). Some of the information currently on this Wikipedia page is currently published on the SDO mission website, and I think it therefore meets the standard. Should the information which does not meet the standard be removed from the page? -Teridon 19:38, 31 January 2006 (UTC)

As nice as it might seem to have access to this information, if it's not verifiable, it needs to be removed.--RadioFan (talk) 22:04, 11 February 2010 (UTC)

I think all of the information on the page has now been properly cited -- Teridon (talk) 14:14, 27 February 2010 (UTC)

Orbit

How are the orbit characteristics chosen? How does it provide, as I have heard, eclipse-free operation? Cheers, Matt Whyndham (talk) 10:25, 18 August 2008 (UTC)

I heard this is a rather unique orbit. Can anyone offer a description and an image? Njerseyguy (talk) 19:10, 11 February 2010 (UTC)

Yes, more on the why, please. Why geosynchronus over west Texas? Why inclined at 28.5°? Where are the downlink stations located?DaveCrane (talk) 20:31, 11 February 2010 (UTC)

It's pointed at a new set of 18 meter Ka-band dishes in Las Cruces, NM. That facility was built specifically for SDO though LCROSS makes some use of it as well I think I remember hearing. SDO Presskit page 10 for more info.--RadioFan (talk) 22:11, 11 February 2010 (UTC)

The orbit is inclined at 28.5° because it was launched from Cape Canaveral, from a latitude of 28.5°. This is the minimum possible inclination if no dogleg maneuvers are performed. Note that this is relative to the equator. If the spacecraft were launched at exactly the wrong time of the day, the inclination relative to the ecliptic would be zero. The spacecraft's orbit would be in the same plane as the Earth's orbit around the sun, and there would be a roughly 1.5 hour eclipse every day. Instead, the spacecraft's launch window was selected such that its orbit inclination relative to the ecliptic is maximized, well over 50°. This way, there are eclipse seasons only twice a year, near the times when the sun is along the line of nodes between the spacecraft orbit plane and the ecliptic plane. The higher the inclination, the shorter the eclipse season. For SDO, it is about 2 or 3 weeks, twice a year. An eclipse happens on each orbit, so once per day. Eclipses grow from zero to a maximum length of 1.5hours, then shrink back to zero again at the end of the season. Also, we talk about the spacecraft being parked over New Mexico, but it's really not. It traces out a figure-8 in the sky, as the sub-satellite point varies from 28.5°N to 28.5°S. This means that the ground station mentioned above needs to be steerable, as the spacecraft swings from just a few degrees from the zenith as seen fromt the ground station, to down at about 25 degrees above the southern horizon. The spacecraft does stay above the horizon at all times, so the ground station has continuous 24/7 contact. I know all this because I am on the project, but I can't verify it, so I am sticking this here. 67.173.234.66 (talk) 06:16, 19 March 2010 (UTC)

Very helpful thanks. I'm tempted to put that in the article even without a published source. - Rod57 (talk) 14:27, 1 December 2019 (UTC)

Sadly the SDO presskit link no longer works and search doesn't find 418329main_SDO_PressKit.pdf. - Rod57 (talk) 14:48, 3 January 2024 (UTC)

Expand the article

This article really needs to be expanded...I've also uploaded some related pictures to the commons that may help.Smallman12q (talk) 14:14, 13 February 2010 (UTC)

Could someone add some more animations/videos from http://svs.gsfc.nasa.gov/search/Series/SDO-Animations.html ?Smallman12q (talk) 15:17, 14 February 2010 (UTC)

First light was yesterday. Images and movies (assembled from stills taken every ten seconds) are available from

• http://sdo.gsfc.nasa.gov/firstlight/
• http://www.youtube.com//SDOmission2009#p/u

It would be great if those who understand solar observation would choose the most encyclopedic of these to transfer to Wikimedia Commons for use in our SDO and Sun articles.

--Hroðulf (or Hrothulf) (Talk)

Mission life - eg amount of propellant etc

• The infobox stats suggest it has 1,400 kg on propellant on-board (or is that total for spacecraft bus) - presumably for initial GS orbit, orbit maintenance and attitude control. Was any used for the initial orbit raising ? How long is the propellant planned to last ?
• How many reaction wheels does it have, and are they all working ?
• Any degradation of spacecraft systems or instruments ?
• - Rod57 (talk) 14:22, 1 December 2019 (UTC)

• Seems consumables were expected to last 10 years, to at least 2020, but in 2020, estimated to last another 10 years. What are the consumables ? Just a storable monopropellant ? - Rod57 (talk) 14:39, 3 January 2024 (UTC)

A Commons file used on this page or its Wikidata item has been nominated for speedy deletion

The following Wikimedia Commons file used on this page or its Wikidata item has been nominated for speedy deletion:

• SDO Launch.jpg

You can see the reason for deletion at the file description page linked above. —Community Tech bot (talk) 18:38, 16 April 2023 (UTC)