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View Full Version : A River of Stars Streaming Across the Sky



Fraser
2006-Mar-17, 04:11 AM
SUMMARY: Astronomers have found a narrow stream of stars extending across the sky for about 45 degrees - 90 times the width of the full Moon. The stream emanates from a cluster of 50,000 stars called NGC 5466, which is located near Ursa Major (or the Big Dipper), and reaches over to the constellation Bootes. The strength of gravity from the Milky Way is different on opposite sides of the star cluster, which causes it to stretch. Outlying stars are no longer held in the cluster and fall behind, creating the stream.

View full article (http://www.universetoday.com/am/publish/starry_northern_river.html)
What do you think about this story? post your comments below.

iantresman
2006-Mar-17, 08:39 AM
Is the report saying that the outlying stars are flung off, away from the spiral galaxy? That would beg a lot of questions. Surely the stars would only appear in a straight line, unless the concentration of "dark matter" was so significant, it was somehow able to hold them in a linear formation?

Seems like a breakdown of conservation of angular momentum to me.

Regards,
Ian Tresman

Blob
2006-Mar-17, 11:12 AM
Hum,
indeed the stars only appear to be a straight line from our perspective - they form an arch that stretches along the orbital path of the cluster...

http://www.bautforum.com/a clearer image (http://www.bautforum.com/showthread.php?t=39353)]

Greg
2006-Mar-17, 05:04 PM
Sounds alot like this cluster could have been a dwarf that got eaten by the milky way.

Fr. Wayne
2006-Mar-18, 05:37 PM
I wonder if any correlation can be formed between this distant stream and our Big Dipper Moving Group?

antoniseb
2006-Mar-18, 07:46 PM
I wonder if any correlation can be formed between this distant stream and our Big Dipper Moving Group?

I'd guess not. The big dipper group is sooooo close to us compared to this stream coming out of both ends of this cluster that we'd have to be looking straight up the stream, which clearly we are not.