Re: Voyager I and II
Posted: Sat Sep 14, 2013 3:34 am
Ok, have they really, finally, absolutely, positively, for sure, finally made up their mind that V'ger left the solar system over a year ago, and it's absolutely positively OFFICIAL
APOD and General Astronomy Discussion Forum
https://asterisk.apod.com/
The Voyager 1 is about 125 AU from the Sun as of August 2013Beyond wrote:
Ok, have they really, finally, absolutely, positively, for sure, finally made up their mind that V'ger left the solar system over a year ago, and it's absolutely positively OFFICIAL
4) The Interstellar medium plasma will continue to have an enhanced density peaking at about 400AUhttp://en.wikipedia.org/wiki/Scattered_disc wrote:
3) <<The scattered disc is a distant region of the Solar System that is sparsely populated by icy minor planets. The scattered-disc objects (SDOs) have orbital eccentricities ranging as high as 0.8, inclinations as high as 40°, and perihelia greater than 30 astronomical units.
Their orbits can extend well beyond 100 AU.
This makes scattered objects "among the most distant and cold objects in the Solar System">>
http://news.discovery.com/space/voyager-1s-radio-glow-glimmers-in-interstellar-ocean-130916.htm wrote:Voyager 1's Glow Glimmers in Interstellar Space
by Ian O'Neill, Discovery, Sep 16, 2013
<<One of the most iconic photographs in spaceflight history is that of Earth, seen from a distance of 4 billion miles by the outward bound Voyager 1 spacecraft. The 1990 “Pale Blue Dot” gave the world a profound realization that everybody — from all human history that has ever existed — lived on that one tiny speck in the distance, as legendary science communicator Carl Sagan remarked at the time. Now, 23 years later, a photograph of another “pale blue dot” has been released by NASA — the faint signal from Voyager 1′s radio transmitter reaching us from interstellar space after traveling 11.5 billion miles from Earth.
Last week, NASA confirmed that Voyager 1 had officially left the solar system’s heliosphere, escaping from the heliopause and entered interstellar space, the first man made object to leave the sun’s domain. Therefore, this pale blue radio speck is the first man made radio signal ever to be received from interstellar space. According to NASA, the signal being generated by Voyager 1 is very weak. The spacecraft’s main radio transmitter generates just 22 watts — the approximate radiated power of a refrigerator light bulb. But to a huge radio array like the VLBA, Voyager 1′s signal is easily detectable as a faint radio glimmer in the darkness of the interstellar ocean.
“They were able to see a blue speck,” Suzanne Dodd, Voyager’s project manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., said during a news conference Thursday. “And this image represents the Voyager radio signal as seen by the world’s most sensitive ground-based telescope. It’s just a speck in amongst a sea of darkness.”
It is estimated that Voyager 1′s dwindling power supply — generated by three radioisotope thermoelectric generators (RTGs) — will only allow for the spacecraft’s science instruments to be powered up until 2020 and then by 2030, the mission will go silent and Voyager 1′s faint radio glimmer will be extinguished for good.>>
What if it's a collect callBeyond wrote:
Quick, answer the phone. It's us calling.
neufer wrote:http://news.discovery.com/space/voyager-1s-radio-glow-glimmers-in-interstellar-ocean-130916.htm wrote:Voyager 1's Glow Glimmers in Interstellar Space
by Ian O'Neill, Discovery, Sep 16, 2013
<<One of the most iconic photographs in spaceflight history is that of Earth, seen from a distance of 4 billion miles by the outward bound Voyager 1 spacecraft. The 1990 “Pale Blue Dot” gave the world a profound realization that everybody — from all human history that has ever existed — lived on that one tiny speck in the distance, as legendary science communicator Carl Sagan remarked at the time. Now, 23 years later, a photograph of another “pale blue dot” has been released by NASA — the faint signal from Voyager 1′s radio transmitter reaching us from interstellar space after traveling 11.5 billion miles from Earth.
Last week, NASA confirmed that Voyager 1 had officially left the solar system’s heliosphere, escaping from the heliopause and entered interstellar space, the first man made object to leave the sun’s domain. Therefore, this pale blue radio speck is the first man made radio signal ever to be received from interstellar space. According to NASA, the signal being generated by Voyager 1 is very weak. The spacecraft’s main radio transmitter generates just 22 watts — the approximate radiated power of a refrigerator light bulb. But to a huge radio array like the VLBA, Voyager 1′s signal is easily detectable as a faint radio glimmer in the darkness of the interstellar ocean.
“They were able to see a blue speck,” Suzanne Dodd, Voyager’s project manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., said during a news conference Thursday. “And this image represents the Voyager radio signal as seen by the world’s most sensitive ground-based telescope. It’s just a speck in amongst a sea of darkness.”
It is estimated that Voyager 1′s dwindling power supply — generated by three radioisotope thermoelectric generators (RTGs) — will only allow for the spacecraft’s science instruments to be powered up until 2020 and then by 2030, the mission will go silent and Voyager 1′s faint radio glimmer will be extinguished for good.>>
This blue spec image represents the resolution of a point sourcewonderboy wrote:
Out of interest, how big is this blue spec in real terms, compared to the earth. obviously its a radio wave travelling towards earth, i imaging that the waves get bigger and the blue spec larger the further away voyager gets? so if this beam were to hit earth would it take up a small amount of earths surface or a large part due to the distance travelled? theres a reason im asking!
Yes...which is one reason that NASA is experimenting with laser communication.wonderboy wrote:
what if similar signals were being beamed to us from faaaaaaaaaaar away.
would the beam not be so wide as to be undetectable?
http://en.wikipedia.org/wiki/Free-space_optical_communication#Usage_and_technologies wrote:<<In outer space, the communication range of free-space optical communication is currently of the order of several thousand kilometers, but has the potential to bridge interplanetary distances of millions of kilometers, using optical telescopes as beam expanders. In January 2013, NASA used lasers to beam an image of the Mona Lisa to the Lunar Reconnaissance Orbiter roughly 240,000 miles away. To compensate for atmospheric interference, error correction code algorithm similar to that used in CDs was implemented. The distance records for optical communications involved detection and emission of laser light by space probes. A two-way distance record for communication was set by the Mercury laser altimeter instrument aboard the MESSENGER spacecraft. This infrared diode neodymium laser, designed as a laser altimeter for a Mercury orbit mission, was able to communicate across a distance of 15 million miles (24 million km), as the craft neared Earth on a fly-by in May, 2005. The previous record had been set with a one-way detection of laser light from Earth, by the Galileo probe, as two ground-based lasers were seen from 6 million km by the out-bound probe, in 1992.
Secure free-space optical communications have been proposed using a laser N-slit interferometer where the laser signal takes the form of an interferometric pattern. Any attempt to intercept the signal causes the collapse of the interferometric pattern. This technique has been demonstrated to work over propagation distances of practical interest and, in principle, it could be applied over large distances in space.>>
Maybe it is, maybe it isn't. It's our only example. A sample size of one isn't much to go on. Weird things happen with your research if your sample is too restricted.makc wrote:Earth evolution is nothing special.