Last week I reported on information from a source on the WISE mission that no new red dwarfs had yet been discovered out to a distance of 10 light years. This past weekend I received an email from my source apologizing for mis-typing. He had meant to say no brown dwarfs — not red dwarfs — out to a distance of 10 light years. And as I mentioned with the earlier post, the data analysis continues and there may be surprises yet to come.
A nearby brown dwarf is something I’ve been writing about here for some time, pondering its implications and wondering whether one might actually turn up that was closer than the Alpha Centauri stars. So the news is that no brown dwarfs matching the description have yet turned up, but the hunt continues.
The latest published list that I have found has turned up 100 brown dwarfs but none have been shown to be closer than 9 light years or so. “THE FIRST HUNDRED BROWN DWARFS DISCOVERED BY THE WIDE-FIELD
INFRARED SURVEY EXPLORER (WISE)” in the astrophysical journalpblished in Dec 2011), still, the exact location of most of these sources are uncertain. Notice that looking at this from a practical POV, the lighter brown dwarfs are thought to be more numerous but also dimmer. it is also true that the large swath of the sky in the direction of the milky way is difficult to study because of the background. What is needed is another round of observation from WISE, which is still functional athe the 3 and 5 micron wavelengths,but dormant. Such a program may at the cost of about 10 million dollars for another say 14 months of observation this is about 4% of te overall cost of the mission to add a LOT of new data. A follow on survey after waiting a year’s time interval would really help sort our which compact sources have high proper motions. It was my fantasy to win the Powerball lotto and use 4% of the winnings to fund another round of wise observations. Alas that did not happen, anyone else have a plan B? I see one guy is willing to spend millions at sea, recovering some useless space junk from Apollo era ; maybe we can get some funding to find more asteroids and Brown Dwarfs….. this is the ultimate space tourism… tour all of the nearby solar neighborhood!
this is one newest discovery of WISE ( 26 Mar 2012) :
A T8.5 Brown Dwarf Member of the Xi Ursae Majoris System
http://arxiv.org/abs/1203.5764
Xi Ursae Majoris System it’s quadruple star system at 8 pc, Now with a fifth brown dwarf companion orbiting the system
Xi Ursae Majoris is one busy system. Still holding out hope here for an object closer than 4.22 ly. One thing to keep in mind is that distance estimates are quite often revised given fresh data. Objects thought to be as nearby as 20 or 15 light-years during the 1980’s have had their positions adjusted by, for example, Hipparcos. Science, especially astronomy, requires time.
Imagine: at some point in coming decades, enthusiasts and scientists alike may be breathlessly hoping to detect with our modern instruments sunless “rogue” planets in the void between the stars, not just the “warm” brown dwarfs at the threshold of our ability to detect now.