Sentences with phrase «ground than a satellite»

Not exact matches

Internet connectivity is delivered to planes either by expensive ground - based cell towers or via even more expensive satellite relays, which means there will always be a significantly higher cost for this sort of access than there is for the terrestrial equivalent.

This will be a major moment if successful, and will make SpaceX the first US company to successfully launch its first prototype internet satellites intended for low Earth orbit (200-1000 miles above Earth), a factor that would make them far more viable as a competitive alternative to ground - based internet than the current heavyweights in geostationary orbit (30,000 + miles above Earth).

The cost of the space segment of such a system would be low, as compared with ground - based TV systems: launching, rocket and satellite would cost about $ 10 million, including allowance for possible launch failure, to which should be added not more than $ 5 million for the ground station «up - link».

For more than a decade, scientists at Haystack Observatory have studied plasma plume phenomena using a ground - based technique called GPS - TEC, in which scientists analyze radio signals transmitted from GPS satellites to more than 1,000 receivers on the ground.

However, Ling notes that Pan's team recovered only about one photon out of every 6 million sent from the satellite — far better than ground - based experiments but still far too few for practical quantum communication.

Using satellites, ground - based instruments, and ozone - measuring weather balloons, they showed that since 2000, the September hole shrunk by 4 million square kilometers — an area bigger than India.

More than 500 seismologists and geologists worked for 6 years, using satellite measurements, field surveys, historical records of earthquakes, and geologic evidence of ancient ground motions to document the hazards for all land areas on Earth, says the project's director, Domenico Giardini of the Swiss Seismological Service in Zürich.

Instead of satellites, Locata uses ground - based equipment to project a radio signal over a localised area that is a million times stronger on arrival than GPS.

What makes the case of Google Street View and the mapping of Fort Sam Houston unique is precisely that it involved not overhead satellite imagery but rather cameras on the ground, raising more questions about Pentagon control as technology develops faster than the government's ability — or authority — to regulate it.

But corona - graphs, which are installed on satellites and ground - based telescopes, are not ideal; to protect other instruments from potential damage caused by stray sunlight, they obscure an area slightly larger than the solar disk, blotting out a bit of the corona.

Indeed, while the U.S. government prohibits sale of satellite imagery with ground resolution better than a half - meter, no such rule applies to images from nonsatellite sources.

Whizzing 200 miles above the Martian surface at 2.2 miles per second, it will pick out finer surface details on Mars than commercial satellites can show us on Earth, where cameras have to ride twice as far above the ground to avoid our planet's thicker atmosphere.

But ground - based coronagraphs have their own advantages — while they can only observe the sun in the day during clear weather, they can return data almost instantly, and at a much higher time resolution than satellite instruments.

But the study shows that satellites plus surveys are «vastly more powerful than either one alone,» he says, especially in regions where ground - based surveys are difficult or impossible.

A ground - based telescope that can scan the skies faster than any other of its size could help to protect satellites from collisions with space debris and each other.

A new approach combined ground - based surveys with satellite imaging and yielded a higher density than anticipated

To accomplish those goals, the satellite maintains a position on orbit such that the desired path across the ground does not vary by more than 20 km (12 miles) on each side.

«By combining satellite technology with on - the - ground hydraulic measurements and modeling, we're able to develop much more precise information over a wider area than ever before possible,» Hill said.

Using satellites, the researchers determined that «bottom melt rates experienced by large outlet glaciers near their grounding lines are far higher than generally assumed.»

The mysterious origins of cosmic rays that slam into the Earth?s atmosphere could soon be revealed, thanks to a better ground - based sensor that costs less than balloons or satellites.

On March 26, a little more than a month after the launch, the satellite was in the process of testing its instruments when it abruptly failed to «phone home» as it passed over a ground station.

First detected in 2003, the 2,500 square - mile hot spot was confirmed by NASA satellite data in October 2014, and is said to be responsible for producing the largest concentration of methane in the U.S., and is more than triple a standard ground - based estimate.

Ulvestad was involved in an experiment more than a decade ago in which a NASA communications satellite, TDRSS, was used to test the idea of doing radio astronomical imaging by combining data from space and ground radio telescopes.

Like Ku - band service, Ka - band is also named after a range of microwave frequencies and uses satellite rather than air - to - ground technology.

However, there still is an unexplained discrepancy with the very earliest satellite data showing values that are noticably warmer than the ground data.

- temperature sensors on satellites report much less warming in the upper atmosphere (which the theory of global warming predicts should warm first) than is reported by temperature sensors on the ground.

It makes it seem the ground observations may be wrong, since as everyone knows satellites garner more public respect than boy scout weatherbird stations on ground.

Now, as you say, there are all sorts of problems with the historical records of sea level but — just as with temperatures — it is likely that measurements from the satellites will be more accurate and less prone to random variation and sampling error than measurements from ground based sensors.

I prefer to start the no - warming period with 2001 because satellite curves that are more accurate than ground based curves used by the Met Office show that the temperature dips to the preceding La Nina level on both sides of the 1998 super El Nino peak.

This is different than claiming that this particular method (whereby satellite data and ground station data are used together in RegEM) provides a more accurate representation of the [unknown] truth than other methods.

Finally, the RSS and MSU satellite data are virtually identical for the period 1979 - 1992... and during that period, both of them show much less warming than the ground data.

Even the first couple of years of the satellite data was problematic as they got results that were some times 6 °C warmer than ocean «ground - truthing» results.

Florida State University's James Elsner said ground data show every decade has been warmer than the last since the middle of the 20th century and satellite data - based observations «show continued warming over the past several decades.»

2b) How much would the difference be in metres on the ground be if the calculation of distance and time from the GPS satellites were calculated according to Newton rather than GR?

This time around, the scientists tapped the vastly improved satellite imagery from Google Earth, which covered more than 210,000 dryland sites, and ground data gathered by the Terrestrial Ecosystem Research Network to carry out a new global analysis of dryland forest cover.

The satellite measurements still have residual calibration effects that must be adjusted for, but these are usually on the order of hundredths of a degree, rather than tenths or whole degrees in the case of ground - based thermometers.

However it should be noted that satellite - based estimates of temperature are a less appropriate measure of land surface temperature than those derived from ground - based stations.

Armed with this information, stakeholders can use preemptive methods such as on - the - ground visits or aerial inspection with high - resolution satellite imagery (less than 5 - meter pixel resolution) to investigate suspected tree cover loss areas.

The satellite data may have its own problems, of course, but there is reason to believe that it may be far more reliable than the ground - based data.

In the 1978 - 96 period the ground data (highlighted in blue) appears to increasingly diverge from the satellite data and increases during the 1978 - 96 period rather than showing the flat trend exhibited by the satellite data.

There has been no reduction in the surface area of grounded ice in the Greenland and Antarctic Ice Sheets, although the mass appears to have declined recently, at least in Greenland, if we can believe the GRACE results, which show more mass loss than earlier satellite altimetry measurements by Johannessen / Zwally (GRL) and Davis / Wingham (Antarctica), which showed net growth over the period 1993 - 2003.

Manfred says: «I would like to see above graphics extended over a longer time than just 1 year, because we have learned this year (with El Nino) that there are significant multi month lags between ground and satellite data sets.»