Webcast On Gravity Assists On February 13, 2001
Subject: Webcast On Gravity Assists On February 13 Date: 9 Feb 2001 18:33 UT From: [EMAIL PROTECTED] (Ron Baalke) Organization: Jet Propulsion Laboratory To: [EMAIL PROTECTED] -- MEDIA RELATIONS OFFICE JET PROPULSION LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011 http://www.jpl.nasa.gov Contact: Guy Webster, (818) 354-6278 INTERNET ADVISORY February 9, 2001 During a live webcast on Tuesday, Feb. 13, an experienced mission planner for interplanetary spacecraft will explain how to choose the best routes for getting to destinations such as Mercury, Mars and Saturn. Charley Kohlhase, who has led trip-planning efforts for NASA missions to most of the planets in the solar system, will also describe how spacecraft can use the gravity of one planet to gain a "slingshot" boost toward a more distant destination. The 90-minute live webcast, "From Ellipses to Gravity Assist," from NASA's Jet Propulsion Laboratory in Pasadena, Calif., will begin at 4:30 p.m. PST (7:30 p.m. EST) at http://www.liveonthenet.com/show.cgi?/2001/nasa/show104/ . Tuning in requires free pre-registration with LiveOnTheNet at http://www.liveonthenet.com . Questions for Kohlhase may be submitted to [EMAIL PROTECTED] . Additional information about the webcast is available at http://www.jpl.nasa.gov/jupiterflyby . Kohlhase will begin with the simple notion of an ellipse, easily created by young viewers, then move on to Kepler's laws and curves such as parabolas and hyperbolas to slowly build a framework for understanding how mission designers at JPL work out their special flight paths to planets. The gravity-assist strategy was first used in 1973 to send NASA's Mariner spacecraft to Mercury by way of Venus. Six weeks ago, NASA's Cassini spacecraft flew near Jupiter for a gravity assist necessary for getting Cassini to Saturn. Kohlhase designed spacecraft missions at JPL, including Mariner, Viking, Voyager and Cassini missions, from the 1960s through the 1990s, twice receiving NASA's Outstanding Leadership Medal, and he continues to consult for JPL. He is also an active artist, author and environmentalist, and has innovated numerous projects and products to communicate space science to the public. JPL is managed for NASA by the California Institute of Technology, Pasadena. # == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
Probing for ETI's Probes in the Solar System
The SETI League Guest Editorial http://www.setileague.org/editor/stride2.htm Probing for ETI's Probes in the Solar System by Scot Stride [EMAIL PROTECTED] http://www.interstellar-probes.org/ Working at JPL for many years and subscribing to its charter tends to affect a person's worldview. Many of the scientists and engineers at this NASA center don't see our robotic probes as just machines, but as extensions of our senses, intellect and being. Indeed, Matt Golombeck used to humorously call the Mars Pathfinder Sojourner rover a "mini-geologist" version of himself. My views are similar. This has indirectly resulted in a personal interest in how advanced ETI might carry out galactic exploration and the construction of interstellar robotic probes. It turns out that a great deal of research and writing on the subject of ETI probes has been done (Freitas, et. al), most of it within the context of complementing radio SETI. Presently, the scientific community, news media and general public associate the term SETI with large radio telescopes and the search for weak signals from far away. Most people know there is a possibility of radio communication (CETI), but many don't realize the unfavorable odds of it working in practice over vast distances and multi-generations of human participants. Professional SETI scientists and engineers know full well the potential of microwave/mm-wave for both radio astronomy and for deep space telecommunications. The SETI focus so far has been on the detection of narrow-band beacons or leakage from ETI civilizations, complemented by radio astronomy observations and mappings to better understand the origins of ET life. However, the SETI lenses that focus so clearly on the task of searching for far away signals are philosophically out of focus when it comes to searching for ETI telecommunications signals that may originate within our solar system. Some time beginning in the early 1970's LDE's (Long-Delayed-Echoes) were a hot topic of discussion. First recorded in the 1920's by Burrows and later advocated by Lunan in the 1970's, these signals were first thought to be radio returns from ETI robotic probes residing in the solar system. It was later showed by Lawton et. al. that these echoes were likely caused by plasma and dust the Earth's upper ionosphere. LDE's are a surprising and unusual natural phenomena that is not fully understood, but they are far too ambiguous to be from ETI robotic probes. Russian scientists have tried some limited searches for probe radio signals within the solar system. Freitas and Valdes did an optical search for probe artifacts (SETA) at the five earth-moon-sun libration points. These searches, also done within the SETI context, were primarily negative and inconclusive. This fleeting, yet serious, research was not embraced by mainstream SETI scientists and for the most part ignored. It's chilling to think what the reaction would have been if Freitas and Valdes had detected and verified a robotic probe stationed at L5. Aside from these few studies, nothing else has been done within the SETI context to actively search for radio signals from possible ETI probes in the solar system, but there is room for hope. Presently at least one SETI telescope is periodically observing robotic probe transmissions emanating just beyond 75 AU. These are not ETI, but from NASA's Pioneer 10 spacecraft. Pioneer 6 has been observed occasionally, as is Galileo when it's Jovian orbit is suitable. Detection of these S-band signals demonstrates that both radio and optical SETI have the capability to search the solar system for signals that could be considered ETI in origin. ETI probe radio transmissions would be clearly distinguishable from those of our own deep space robotic probes, because we know the locations, frequencies and Doppler of our spacecraft. It might be argued that if an ETI probe were within our solar system and transmitting a signal toward Earth, intended for us or not, that we would detect it with the current SETI effort. No one with a working knowledge of the current SETI effort would accept this allegation for any frequencies other than the 1 to 3 GHz band (particularly the 18 and 21 cm lines). Millimeter-wave or optical signals from an ETI probe may be illuminating Earth right now, and we would never know it. Why not? Because a wideband, all-sky survey is not actively underway. This kind of effort, which I term Solar System SETI (S3ETI), was briefly carried out at the JPL Deep Space Tracking Network during 1992-93, as a part of the NASA HRMS (High Resolution Microwave Survey) effort. At the time, the intent was not to search for ETI probe microwave transmissions within the solar system, but it certainly could have found them if they were there and between 1 and 10 GHz. Nothing was detected, but one year is not very long to find much of anything.
Controlled Descent By NEAR Underway
Date: Mon, 12 Feb 2001 08:59:17 -0800 (PST) From: [EMAIL PROTECTED] Subject: Controlled Descent By NEAR Underway Reply-To: [EMAIL PROTECTED] To: undisclosed-recipients:; http://near.jhuapl.edu/news/flash/01feb12_1.html Controlled Descent Underway February 12, 2001 The first controlled descent to an asteroid is underway! NEAR Shoemaker successfully moved out of its circular orbit today at 10:32 a.m. (EST), firing its thrusters and heading toward the surface of Eros. "This was the critical opening maneuver," says NEAR Mission Operations Manager Robert Nelson, monitoring the spacecraft from the NEAR Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. "Now we'll work with the NEAR navigation team [at NASA's Jet Propulsion Laboratory] to examine the pictures and ranging data taken after the engine burn, and establish the spacecraft's location. Then we'll send one more set of commands to NEAR Shoemaker's computer, setting the timing for the final descent and imaging sequences later today." The spacecraft was about 16 miles (26 kilometers) from Eros when the maneuver started. NEAR Shoemaker will essentially drift toward the rotating asteroid for the next three hours, until starting the series of four "braking" maneuvers that will slow it from 20 mph to about 5 mph. The first of these engine bursts will occur when NEAR Shoemaker reaches a point 3 miles (5 kilometers) above Eros. After taking close-up images of the surface during the last leg of its journey, the craft is expected to touch down in an area outside Eros' saddle-shaped depression, Himeros, at approximately 3:05 p.m. EST. == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
Pioneer 10 Status Report for February 9, 2001
http://spaceprojects.arc.nasa.gov/Space_Projects/pioneer/PNStat.html STATUS UPDATED: 09 February 2001 PIONEER MISSIONS Pioneer 10 distance from Sun: 77.12 AU Speed relative to the Sun: 12.24 km/sec (27,380 mph) Distance from Earth: 11.47 billion kilometers (7.13 billion miles) Round-trip Light Time: 21 hours 16 minutes We have now successfully processed tracks, previously thought null. The scientific data on the 5 and 6 August 2000 passes of Pioneer 10 were sent to Dr. Van Allen, who reports clean data. The cosmic ray intensity was identical within statistics to that on DOY 190 (7/9/00), the date of the last maneuver. There was no further decrease, indicating that the Solar wind boundaries have yet to be reached. Larry Lasher, Pioneer Project Manager The latest Pioneer 10 attempt on January 16, to acquire the downlink unfortunately was unsuccessful. Currently, we are attempting to get tracks on the busy DSN schedule that would allow an uplink and downlink support (competition for time includes Galileo, Cassini and Ulysses). This will let the DSN send up a strong stable signal and try to lock up with a coherent downlink signal. The effort is further complicated by the 21 hour round-trip light time. It looks like we will have to wait until March. However, there may be another downlink-only attempt in a few weeks. Project Phoenix is observing Pioneer 10 at Arecibo in Puerto Rico through the auspices of the SETI Institute. Their observation dates are from Feb 26 to March 5 and from March 8 through 18 about an hour each night. == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
2001: A Space Odyssey reviewed on Florida Today
The 'Odyssey' continues It is the only film about space travel that is regularly chosen by critics as one of the 10 best films ever made, a film that continues to fascinate audiences and provoke lengthy discussions more than 30 years after its initial release in 1968. And, even though Stanley Kubrick's "2001: A Space Odyssey" has now become officially outdated as an accurate prediction of humanity's future, it remains a film with much to say about what humans are and where we are going. http://www.floridatoday.com/news/editorial/stories/2001/feb/edit021101a.htm == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
NEAR Touchdown on Eros!
From: Peiser Benny [EMAIL PROTECTED] To: cambridge-conference [EMAIL PROTECTED] Subject: Touchdown! Date: Mon, 12 Feb 2001 20:17:45 - From Ron Baalke The NEAR Shoemaker spacecraft has successfully touched down on the surface of Eros. Transmissions from the spacecraft are still being received from the surface of the asteroid. Preliminary data indicates the spacecraft has fallen on its side. Ron Baalke http://near-mirror.boulder.swri.edu/ == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
