| Revision as of 21:41, 10 March 2005 editIcairns (talk | contribs)76,837 edits categ Unidentified celestial bodies -> Astronomical objects← Previous edit | Revision as of 13:00, 2 April 2005 edit undoFayssalF (talk | contribs)Extended confirmed users43,085 edits {{{Skepticism}}}Next edit → | ||
| Line 1: | Line 1: | ||
| {{wrongtitle|title=Radio source SHGb02+14a}} | {{wrongtitle|title=Radio source SHGb02+14a}} | ||
| '''SHGb02+14a''' is an interesting radio source and candidate in the ] discovered by ] and announced in '']'' on ], ]. This weak source was observed three times at 1420 ] |
'''SHGb02+14a''' is an interesting radio source and candidate in the ] discovered on March ] by ] and announced in '']'' on ], ]. This weak source was observed three times at 1420 ] and emitted from between the constellations ] and ]. According to the '']'', the 1420 MHz ] would be one that extraterrestrials would use, since it is one of the main frequencies at which ], readily absorbs and radiates energy. | ||
| ⚫ | A more skeptical article concerning the discovery was written by ]. | ||
| There has been more skepticism than a welcoming to the event. Most researchers dismissed the signal as an artifact of random chance, cosmic noise or maybe just a glitch in the technology. | |||
| Another reason for the skepticism is that there is no ] within 1000 ]s of that direction. | |||
| Some of the most explicit arguements were edited by the * article. It argues that ''] is just a ] with an electron in its ]; both the ] and the ] have a ] ] moment. There is a tiny ] difference between alignment and anti-alignment, and when the system flips, you get a tiny ] at 1420 MHz (a wavelength of 21 cm, hence the ]). There's a lot of neutral ] in the ] and therefore there is a lot of ] at 1420 MHz. It was one of the first detections made when we invented ].'' | |||
| It adds that ''there are some more oddities to the signal. In the three times it has been detected, it has ] shifted quite rapidly. This is presumably due to the motion of the source itself relative to us. A shift of 37 Hz per second (the maximum observed) would mean that the source was accelerating at around 8 meters/second^2. If the civilization was sending out a signal from a home planet in ] around the Sun, this would imply a pretty rapid rate of rotation. The Earth's acceleration about the Sun is much less.'' | |||
| In the same article, Simon argues that ''Another oddity about this signal is that it lasts around a minute or so. This implies that the region that it came from was less than a light-minute in size. This is very unusual, since the ] emission is usually very faint, and requires a large amount of material spread out over much larger scales. I don't know the amplitude of the signal, but from what I understand, one light-minute (less than the size of the Earth's radius of orbit) is a fantastically tiny region to get a significant amount of 21 cm emission from. More indeed, the fact that signals never lasted longer than a minute which makes it difficult to analize them.'' | |||
| ⚫ | A more skeptical article concerning the discovery was written by ]. | ||
| However the controversy over the SHGb02+14a, it is still an interesting signal. So the search continues. | |||
| ==External links== | ==External links== | ||
| Line 8: | Line 23: | ||
| * | * | ||
| * | * | ||
| * | |||
| ] | ] | ||
Revision as of 13:00, 2 April 2005
The correct title of this article is Radio source SHGb02+14a. It appears incorrectly here due to technical restrictions.SHGb02+14a is an interesting radio source and candidate in the Search for Extra-Terrestrial Intelligence discovered on March 2003 by SETI@home and announced in New Scientist on September 1, 2004. This weak source was observed three times at 1420 megahertz and emitted from between the constellations Pisces and Aries. According to the New Scientist, the 1420 MHz frequency would be one that extraterrestrials would use, since it is one of the main frequencies at which hydrogen, readily absorbs and radiates energy.
There has been more skepticism than a welcoming to the event. Most researchers dismissed the signal as an artifact of random chance, cosmic noise or maybe just a glitch in the technology.
Another reason for the skepticism is that there is no star within 1000 light years of that direction.
Some of the most explicit arguements were edited by the *The blogging of the president:2004 article. It argues that Hydrogen is just a proton with an electron in its orbit; both the proton and the electron have a magnetic dipole moment. There is a tiny energy difference between alignment and anti-alignment, and when the system flips, you get a tiny photon at 1420 MHz (a wavelength of 21 cm, hence the 21 cm line). There's a lot of neutral Hydrogen in the galaxy and therefore there is a lot of radiation at 1420 MHz. It was one of the first detections made when we invented radio astronomy.
It adds that there are some more oddities to the signal. In the three times it has been detected, it has doppler shifted quite rapidly. This is presumably due to the motion of the source itself relative to us. A shift of 37 Hz per second (the maximum observed) would mean that the source was accelerating at around 8 meters/second^2. If the civilization was sending out a signal from a home planet in orbit around the Sun, this would imply a pretty rapid rate of rotation. The Earth's acceleration about the Sun is much less.
In the same article, Simon argues that Another oddity about this signal is that it lasts around a minute or so. This implies that the region that it came from was less than a light-minute in size. This is very unusual, since the 21 cm line emission is usually very faint, and requires a large amount of material spread out over much larger scales. I don't know the amplitude of the signal, but from what I understand, one light-minute (less than the size of the Earth's radius of orbit) is a fantastically tiny region to get a significant amount of 21 cm emission from. More indeed, the fact that signals never lasted longer than a minute which makes it difficult to analize them.
A more skeptical article concerning the discovery was written by The Planetary Society.
However the controversy over the SHGb02+14a, it is still an interesting signal. So the search continues.
External links
- New Scientist article
- Article on the Planetary Society's website
- SETI Project signal candidate page
- SETI range calculator