Keeping the Deep Space Network working
According to this article in the journal Science, planetary scientists are increasingly worried about the future of the Deep Space Network (DSN), operated by JPL and that they use to communicate with their unmanned planetary probes.
For most of its life, the network, run by the Jet Propulsion Laboratory (JPL) in Pasadena, California, has been metronomic in its reliability. Its three sites, spaced 120° apart around the globe, all have a 70-meter dish built in the 1960s or ’70s, and several newer, 34-meter dishes, which can be arrayed together to match the larger dishes’ downlink performance. The network allows continuous contact with spacecraft anywhere in the solar system—or beyond it, as in the case of Voyager 1, which officially entered interstellar space in 2013. Currently, 35 missions rely on the DSN.
Ironically, the glitches this past December and January largely stemmed from problems with the network’s newest 34-meter antenna, DSS-35, in Canberra, which began operating in 2014, NASA says. Rain and dust compromised an instrument that helps aim it, several other pointing components overheated, and contaminants leaked into a cryogenic refrigerator used to cool an amplifier. NASA says these problems have mostly been fixed, and the Canberra station’s reliability will increase when its next 34-meter antenna, DSS-36, begins operating on 1 October.
Staffing issues have also compounded the hardware problems. In January, the Magnetospheric Multiscale mission, which measures the boundary between Earth’s magnetic field and the solar wind, was, like Cassini, having trouble connecting to DSS-35. Communications could have shifted to another Canberra antenna. But on 22 January, a snowstorm shut down the Goddard Space Flight Center in Greenbelt, Maryland. No one was there to reconfigure the spacecraft, and so the retrieval of a day’s worth of data was delayed.
While there has been a tendency to take the DSN for granted, much of this article seems to me to be a lobbying ploy for more money, budget increases that really aren’t needed that desperately. Almost all the problems listed in the article as well as in the quote above are not really from budgeting problems. In the first case above the failure came from a new antenna, showing that funds had been provided to upgrade the network’s equipment. The second case above was simply a problem caused by an unusual snowstorm.
Moreover, the article noted how Europe has finally built its own network to provide communications for its own planetary probes as well as redundancy to the American network. In addition, the U.S. is negotiating partnerships with several other countries to further supplement its DSN.
In other words, there really isn’t a problem here. The article is informative about this often ignored but essential component of planetary research, but when you read it ignore the pleas for more cash.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
According to this article in the journal Science, planetary scientists are increasingly worried about the future of the Deep Space Network (DSN), operated by JPL and that they use to communicate with their unmanned planetary probes.
For most of its life, the network, run by the Jet Propulsion Laboratory (JPL) in Pasadena, California, has been metronomic in its reliability. Its three sites, spaced 120° apart around the globe, all have a 70-meter dish built in the 1960s or ’70s, and several newer, 34-meter dishes, which can be arrayed together to match the larger dishes’ downlink performance. The network allows continuous contact with spacecraft anywhere in the solar system—or beyond it, as in the case of Voyager 1, which officially entered interstellar space in 2013. Currently, 35 missions rely on the DSN.
Ironically, the glitches this past December and January largely stemmed from problems with the network’s newest 34-meter antenna, DSS-35, in Canberra, which began operating in 2014, NASA says. Rain and dust compromised an instrument that helps aim it, several other pointing components overheated, and contaminants leaked into a cryogenic refrigerator used to cool an amplifier. NASA says these problems have mostly been fixed, and the Canberra station’s reliability will increase when its next 34-meter antenna, DSS-36, begins operating on 1 October.
Staffing issues have also compounded the hardware problems. In January, the Magnetospheric Multiscale mission, which measures the boundary between Earth’s magnetic field and the solar wind, was, like Cassini, having trouble connecting to DSS-35. Communications could have shifted to another Canberra antenna. But on 22 January, a snowstorm shut down the Goddard Space Flight Center in Greenbelt, Maryland. No one was there to reconfigure the spacecraft, and so the retrieval of a day’s worth of data was delayed.
While there has been a tendency to take the DSN for granted, much of this article seems to me to be a lobbying ploy for more money, budget increases that really aren’t needed that desperately. Almost all the problems listed in the article as well as in the quote above are not really from budgeting problems. In the first case above the failure came from a new antenna, showing that funds had been provided to upgrade the network’s equipment. The second case above was simply a problem caused by an unusual snowstorm.
Moreover, the article noted how Europe has finally built its own network to provide communications for its own planetary probes as well as redundancy to the American network. In addition, the U.S. is negotiating partnerships with several other countries to further supplement its DSN.
In other words, there really isn’t a problem here. The article is informative about this often ignored but essential component of planetary research, but when you read it ignore the pleas for more cash.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
rain and dust? anyone try rainX as a coating?
“…The network allows continuous contact with spacecraft anywhere in the solar system—or beyond it, as in the case of Voyager 1, which officially entered interstellar space in 2013. Currently, 35 missions rely on the DSN…”
What? No love for Voyager 2?
From Wikipedia:
“..Voyager 2 is expected to enter interstellar space within a few months of 2016, and its plasma spectrometer should provide the first direct measurements of the density and temperature of the interstellar plasma…”
“…On November 7, 2012, Voyager 2 reached 100 AU from the sun, making it the third human made object to reach 100 AU. Voyager 1 was 122 AU from the Sun, and Pioneer 10 is presumed to be at 107 AU. While Pioneer has ceased communications, both of the Voyager spacecraft are performing well and are still communicating….”
Pioneer 11 is about 94 AUs out, so it and New Horizons will be the 4th and 5th human objects to reach 100 AUs
BTW, anyone know what’s up with Stereo B? They were doing daily updates on the recovery process then took 10 days for the next and it’s been another 10 days now since then with no news.
I received a “solar flare” alert on my phone today and it reminded me to check in on Stereo B :-)
Steve Earle: From what I can tell on the Stereo B update page, the recovery of the spacecraft is not going as smoothly as they would like. The update is very technical, so it simply could be that I do not understand it completely. I would welcome the interpretations of my more engineering-minded readers.
Europe is the only other Deep Space Network that offers around the world coverage (potentially continuous for any given mission). China, India, Japan, and Russia also have Deep Space Networks, but they seem to be at locations that are only within their own borders, so far.
Since the US and Europe have so many active and functional (e.g. the Voyagers) probes, having a large number of antennas around the world helps with keeping in contact with them for collecting data and sending commands. After all, the quantity and quality of the data is the purpose of the probes.
A greater number of active missions — and missions that extend their lives, such as Opportunity — complicate the use of the DSN, which is why more antennas are needed. The DSN also gives priority to rescue missions, such as Stereo-B, as the timeliness of commands and returned engineering data can be crucial to successful rescue, and that priority status also complicates the use of the DSN.
Robert,
I am not a signals engineer, but it sounds like they are still using the low gain antennas and are having trouble with the signal to noise ratio. It can be difficult to pull the signal being sent from the background noise. Low gain antennas also limit the data and command rates, so they are almost certainly eager to get the spacecraft running well enough to use the high gain antenna. Your conclusion that the recovery is not going smoothly seems reasonable.
Budget crapola as states
I’ve been fortunate to tour the Goldstone DSN facility in the California Mojave Desert. Its crown jewel is the huge 70meter antenna commissioned in 1966. The antenna and its base rotates on the circular bottom structure on a large hydraulically lubricated load bearing surface. Its an engineering marvel that’s showing its age, while still an awesome thing to stand under and watch move.
Thanks Bob and Edward for the Stereo B info. I just checked the site again and still no updates. The last entry stated they were requesting 2 hours a day support on the DSN, so either they didn’t get their request or they have had no luck with additional commands. Either way it does not bode well for further recovery of the spacecraft…
Yeah, it looks to me like they are stuck in a low power mode on Stereo B while they try to charge the batteries. There’s talk there about battery pressure and temperature, the temperature being high. They’ve also turned off the reaction wheels to further save power, which indicates their pumping all they can into the batteries. This does indicate two things to me though, first being, with the report of the batteries being hot and they’re being in this charging regime for what has to be days now, the batteries may be damaged. Second, the low power mode would account for their use of only the low gain antenna.
In short, my take away from the report is that they seem to still be concentrating on charging the spacecraft’s batteries and as part of that regime, are using the low gain antenna which accounts for the poor communications. In any event, we’ll need to wait and see what happens. Hope my additional analysis helps out.
Does anyone know whatever became of the tracking radar dishes from the original BMEWS sites? They also were an engineering marvel. Just as impressive were the RF transparent radomes that protected the dishes in a climate controlled environment in some of the harshest weather conditions on earth. Conversion to DSN frequencies would just be a fairly straightforward replacement of waveguide plumbing.
Gealon, Thanks for the added info, I believe you are correct and that it will be a waiting game that hopefully ends with working batteries and ultimately more power for communications.
PeterF, I don’t know about most of them, but I do know where at least one set of dishes and domes are:
https://en.wikipedia.org/wiki/Texas_Tower_4