Archive for March, 2006

A Hard Knock Life for Satellites

Friday, March 31st, 2006

I’m probably giving away my age when I say this, but I remember when our television had a "rabbit ear" antenna, and adjusting the picture just meant moving the "ears" around. Later we had an antenna on the roof. Adjusting the picture meant someone had to climb a ladder to the roof, while someone else yelled out of a window until the picture was clear. Then there was cable. If we lost the signal, we called the cable company and waited.

Now we have satellite TV, and we rarely lose a the signal — except for occasionally during a storm, when it flickers on and off briefly before returning. If we have snow, it can interrupt the signal if it piles up on the dish, but that just means a quick trip to the back yard to brush it off. The dish in the back yard, however, is just a receiver; pointing at at a satellite so high up that a ladder on the roof doesn’t begin to do the trick. So, what happens if a satellite gets bonked by an asteroid or other random space junk?

Well, you lose the signal, which is what happened to a lot of Russians this week when a telecom satellite failed after a "sudden impact" shut down its thermal control, causing it to end up in space disposal orbit.  (Yeah. I didn’t know what that meant either. Apparently there’s a whole part of space where satellites go to die. Who knew?)  New Zealand had an outage too, due to loss of pointing control.  (Another hard knock?) A European satellite got bonked in 1993 when the earth passed through a trail of comet dust. 

So, what to do? Some people are trying to predict problems, and others are working on better materials. (What can withstand getting smacked by an asteroid?) And some are focusing on better monitoring and forecasting of sunspots and space weather (space weather?), which apparently can also cause problems for satellites. 

I can’t say how it all works. I just hope it keeps working. I don’t want to miss any of my favorite shows, and I don’t want to have to climb any higher than the roof.

Playing a Small Part in Understanding Small Things

Friday, March 31st, 2006

The Cern Courier reports on a grassroots project that utilizes the power of the web– and the unused computing power of personal PCs– to help analyze the interstellar dust particles brought back by the Stardust space capsule in early January:

Finding the tiny interstellar dust particles in the Stardust Interstellar Dust Collector will be extremely difficult. The impacts created by interstellar dust can only be found using a high-magnification microscope with a field of view smaller than a grain of salt….. Stardust@home enables public volunteers to help in this task, which is done more accurately by humans than by any pattern recognition software. After a web-based training session, passing a test and registering, volunteers download a virtual microscope (VM). The VM automatically connects to the Stardust@home server and downloads stacks of images created by an automated microscope at the Cosmic Dust Lab at the Johnson Space Center. Each field can then be searched for interstellar dust impacts by focusing up and down with a focus control. The first images for scanning should become available in April and the project should be completed by October.

For more information on on Stardust@home, click here.

Brazil Joins Astronaut Club

Thursday, March 30th, 2006

"Brazil’s first astronaut blasted off from earth on a cloudless day on Thursday with a Russia-U.S. crew bound for the orbiting International Space Station," Reuters reports:

Marcos Pontes, a 43-year-old Brazilian Air Force pilot, was hunched inside the spacecraft with Russian cosmonaut Pavel Vinogradov and U.S. astronaut Jeffrey Williams, both of whom were starting a six-month rotation in space….

Pontes, who packed a Brazilian soccer team shirt, returns to earth in 10 days with the outgoing crew, American Bill McArthur and Russian Valery Tokarev.

The Russian Soyuz rocket took off at 0230 GMT (3:30 a.m. British time) from the Baikonur cosmodrome, on a piece of Kazakh steppe rented by Russia from its ex-Soviet neighbour. It is scheduled to dock in two days’ time.

Soon after launch the first stage of the rocket fell away and tumbled back to earth, still glowing orange, while the Soyuz sped higher and higher into space.

"It’s beautiful, absolutely beautiful," said Michael Baker, a NASA international space station programme manager.

Russian spacecraft bear the responsibility for shipping crew and supplies to the station after NASA grounded its shuttle fleet in July when it failed to fix a technical problem that killed seven astronauts in 2003.

Soyuz rockets have proved safer than the shuttle despite their 1960s heritage.

 

iPod-from-Space Mystery Unfolds?

Wednesday, March 29th, 2006

After getting some comments from our readers on the iPod-from-Space post, concerning the accuracy of the dates in the Terrabyte screenshot, we dropped an email to TerraServers to see if we could get any further answers. Here’s what they sent us:

You can’t get the whole planet shot all in one day, so it is made up of various collection dates in 1999. When you have a large date range over a big mosaic like this, the company that took it will often just give the month or year taken. In cases like this, to specify a date, we use the first of the month or first of the year. So, all of the 1/1/1999 pictures would be made up of shots taken during 1999 or possibly some in 1998 or 2000. They’d probably go with the year with the majority. This 15m satellite mosaic covers most or all of the earth’s surface and is the last full collection that we know of. That’s partly because one of the Landsat satellites failed or crashed a couple of years back. It is the main baseline imagery that us and the rest of the major imagery sites use to show basic coverage worldwide. That’s why you’ll see the same picture between us because it’s all coming from the same original imagery.

I was able to pick off the coordinates from the image at full size on Flickr and get to it on our site. My best guess from looking at the area just north of it is that it’s part of a strip mining operation. The “screen” of the iPod might be a big holding pond or quarry pond

 Anywhere from 1998 to 2000, huh? Strip mine? Quarry pond? Sounds feasible, given the original post, but still doesn’t nail down an absolute date. So perhaps it still remains a mystery.

iPod From Space Falls to Earth

Tuesday, March 28th, 2006

It was fun while it lasted, huh? We saw the Gizmodo post yesterday, about the iPod advertisement that’s viewable from space, and filed it away for future reference. Turns out that, after rocketing around the blogosphere, it’s probably not what it looks like. Some intrepid bloggers noted that the Terrabyte satellite image for that location on January 1, 1999 — before the iPod launched — looks the same  as it does Google Earth today.

We’ve got both images. Care to guess which is which?

 

 

It gets better. The Terabyte server’s been rather busy, so when we got a chance we grabbed a screenshot of the whole page. (Note the date.)

 


terrabyte1999

And we grabbed a shot of Google Earth as well. 


googleearth

And fun would it bit of snark? The author of the the original post suggests he knows the identity of the legendary space-iPod’s owner.

It is just me? Do things not always look like what they are when seen from space? Or is am I seeing ancient Egyptian royalty here? 

So, is there anything else that looks like an iPod from space? How many can you find?

NASA & Sweden in Moonbase Race?

Monday, March 27th, 2006

The history book on the shelf,
Is always repeating itself…

Abba – “Waterloo” 

We’ve already been to the moon (unless you believe that the whole thing was done on a movie lot), but it looks like we’re going to stay a while the next time we go back. There just one question. Who’s gonna get there first? I experienced a little brain tickle this morning when I saw the news item that NASA is quietly planning a moonbase

For the first time since 1972, the United States is planning to fly to the moon, but instead of a quick, Apollo-like visit, astronauts intend to build a permanent base and live there while they prepare what may be the most ambitious undertaking in history — putting human beings on Mars.

It sounded vaguely familiar, and not because the presdient announced a plan to return to the moon a couple of years ago. I felt that brain tickle because I remembered hearing just a week or so ago that someone else was planning to do the same thing.

A quick search through my bookmarks, and I had the answer. In the race to colonize the moon, NASA has at least one competitor: Sweden.

The proof comes in the form of the innocent-looking SMART-Centre which, according to various reports, has assembled a consortium of more than 50 partners – including Japan’s Shimizu Corporation, US NASA contractor Orbitech and the UK’s Cranfield University – to turn the centre’s Dr. Niklas Järvstråt’s dreams of extraterrestrial conquest into reality.

 You won’t find much about a moonbase at the SMART-Center homepage. For that you’ll have to dig into their projects for the vision statement.

We have already taken the one small step for mankind and landed on the moon. We have seen it, we have conquered it, we have explored it – but our presence has not been sustained. For the benefit of mankind, the survival of our natural resources on Earth and for the proliferation of space exploration, it is now time for the next logical step – an international lunar colony. A colony where men, women and children can live without the need of a continuous supply of materials and technology from Earth; a self-supporting colony where the great circle of life can be sustained in its entirety by lunar raw materials and where all life-sustaining products will be manufactured in situ.

The Swedes have some other big plans in mind beyond moon — including exploring Mars, asteroids, other solar systems, etc., and trying their hand at world peace — but will it be more than they can handle? Then again, as the article linked above notes, NASA has its hands full with emptying its already-tapped-out pocketbook for space shuttle repairs, with a 2020 back-to-the-moon deadline looming over it. The Swedes have a deadline for lunar construction and immigration to happen sometime between 2018 and 2024.

So, it’s not a question of if human beings will return to the moon, but a matter of when and under which flag. Anyone care to lay bets?

New Falcon 1 Rocket Destroyed on Maiden Voyage

Monday, March 27th, 2006

An engine fire destroyed Space-X’s Falcon 1 rocket on its maiden voyage today, according to reports.

Close up of Falcon 1 Engine Fire The International Reporter has early details:

The US vehicle, developed by the Space Exploration Technologies Corp, was destroyed soon after take-off from the Marshall Islands in the Pacific Ocean. The vision of Elon Musk, co-founder of the electronic payment system PayPal, the Falcon was designed to cut the cost of current satellite launches.

An onboard camera appeared to show the rocket rolling out of control shortly before the video signal was lost….

The rocket was attempting to carry a 19.5kg satellite to a low-Earth orbit of 450km. The satellite, FalconSat-2, was built by US Air Force Academy cadets to investigate the phenomenon known as "space weather".

Elon Musk has additional details on the Space-X blog

The good news is that all vehicle systems, including the main engine, thrust vector control, structures, avionics, software, guidance algorithm, etc. were picture perfect.  Falcon’s trajectory was within 0.2 degrees of nominal during powered flight. 

 

However, at T+25s, a fuel leak of currently unknown origin caused a fire around the top of the main engine that cut into the first stage helium pneumatic system.  On high resolution imagery, the fire is clearly visible within seconds after liftoff.  Once the pneumatic pressure decayed below a critical value, the spring return safety function of the pre-valves forced them closed, shutting down the main engine at T+29s. 
 

It does not appear as though the first stage insulation played a negative role, nor are any other vehicle anomalies apparent from either the telemetry or imaging.  Falcon was executing perfectly on all fronts until fire impaired the first stage pneumatic system.
 

Our plan at this point is to analyze data and debris to be certain that the above preliminary analysis is correct and then isolate and address all possible causes for the fuel leak.  In addition, we will do another ground up systems review of the entire vehicle to flush out any other potential issues.
 
The company says it is too soon to determine when the next flight will take place. 

 

 

 

Making MobTV Work

Friday, March 24th, 2006

I’ve decided to try my hand at coining a new phrase: mobTV. I figure if mobile blogging can become "moblogging", then mobile television can become "mobTV." Besides, as I’m learning more about it and writing more about it I’m going to need a more efficient way to refer to it if I want to keep up, given the way its spreading and the number of terms I have to learn. 

Since my last post on the mobTV taking off in Korea, it looks like mobTV is coming to China next, if Radioscope has its way.  And on a pretty cool looking phone, if you ask me.

Samsung MobTV PhoneRadioscape has won contracts to supply five more Digital Multimedia Broadcast (DMB) and Enhanced Packet Mode (EPM) transmission systems for mobile TV operators in China, bringing the total to nine in the past few months.

 The company says the contracts are the fruits of at least two years of courting Chinese authorities about its DAB-based mobile TV technology and helping them evaluate the most appropriate technologies for the service, and choosing between DMB, DVB-H and DMB-T.

From there it gets interesting. Qualcomm announced last year that it was bringing mobTV to the states via a  technology called MediaFLO, which Verzion also adopted late last year. For the curious, Mobile Content News has video of MediaFLO in action. (Found via Engadget, and I believe that’s Shrek on the small screen.)  The question is, can it work? The experts aren’t  exactly in agreement. Depending on who you ask, MediaFLO and another technology called DVB-H are doomed because EV-DO already gets the job done and new networks are too expensive to build and support, or DVB-H will be the de facto standard once spectrum allocation problems are solved.

Got all that? Good, because I’m about to add some French to the mix. Alcatel just announced that it’s overcome the spectrum allocation issue by using a satellite frequency.

With the help of satellites, Alcatel aims to overcome a key hurdle in rolling out broadcast television services over mobile phones: the lack of available spectrum. 

The French telecommunications-equipment manufacturer proposes using the widely available S-Band frequency reserved for satellites to transmit broadcast signals both terrestrially and via satellite to mobile phones based on the DVB-H (digital video broadcasting – handheld) standard, instead of the UHF band. 

… The Alcatel proposal calls for equipping base stations with S-Band repeaters and, in addition, using satellites capable of transmitting in the S-Band to deliver content to 3G (third-generation) phones enabled with DVB-H technology in three different ways: base-station streaming, base-station broadcasting and satellite broadcasting.

The article also does a good job of explaining the drawbacks of the three delivery systems. Streaming offers unlimited channels and great indoor coverage, but only for a limited number of users on a network. Broadcast matches it on indoor coverage, and supports unlimited users, but only 27 channels. Satellite matches them on channels and user support, but falls short on indoor coverage. Alcatel claims the answer is an "intelligent content-management system" that seamlessly chooses the right delivery system. 

Leave it to the French to come up with an elegant solution. I just hope it works well enough to eventually get picked up in the U.S. It would be great to catch up on Desperate Housewives reruns on the subway, and get all the way up the street to my office without losing the signal.

No More Dial-Up to the Outer Planets

Thursday, March 23rd, 2006

It may be surprising to many people, but when NASA scientists receive data back from distant probes, their experience is akin to downloading "Bohemian Rhapsody" (or, pick your own epic-length song) on 56K. Which is to say, there’s a lot of waiting involved. But that could change:

 Researchers at the Massachusetts Institute for Technology have developed a tiny light detector that could one day boost interplanetary communications to broadband speeds.

Images from Mars, like this computerized one of a canyon, are transmitted at a data rate of 128,000 bits per second.

The work could permit the transmission of color video between astronauts and satellites and scientists on Earth across interplanetary distances, something that is not practical with current technologies.

The new light detector improves detection efficiency to 57% at a wavelength of 1,550 nanometers — the same wavelength used by optical fibers on Earth to carry broadband signals to homes and offices. Currently, light detectors only absorb about 20% of the light they receive.

"It can take hours with the existing wireless radio frequency technology to get useful scientific information back from Mars to Earth," said study team member Karl Berggren from the Massachusetts Institute of Technology. "But an optical link can do that thousands of times faster."

The work is detailed in the Jan. 23 issue of the journal Optics Express

 

Hunting for Stars, Through the Light

Wednesday, March 22nd, 2006

This is a great effort:

Join thousands of other students, families, and educators by participating in GLOBE at Night – an international event designed to observe and record the visible stars as a means of measuring light pollution in a given location. Participation is open to anyone – anywhere in the world – who can get outside and look skyward during the week of March 22-29, 2006! There is no cost to participate in GLOBE at Night. Help us reach our goal of 5000 observations from around the world!

 The National Optical Astronomy Observatory, which is sponsoring the event, also has a cool online tool that allows you to witness the changes in the night sky that result from light pollution.

For more information, download the GLOBE Family Activity Packet PDF (in English and Spanish) or subscribe to the GLOBE email list.