Featured Research

from universities, journals, and other organizations

Boundary Between Earth's Upper Atmosphere And Space Has Moved To Extraordinarily Low Altitudes, NASA Instruments Document

Date:
December 16, 2008
Source:
NASA/Goddard Space Flight Center
Summary:
Observations made by NASA instruments onboard an Air Force satellite have shown that the boundary between the Earth's upper atmosphere and space has moved to extraordinarily low altitudes.

The height of the ionosphere/space transition is controlled in part by the amount of extreme ultraviolet energy emitted by the Sun and a somewhat contracted ionosphere could have been expected because C/NOFS was launched during a minimum in the 11-year cycle of solar activity. However, the size of the actual contraction caught investigators by surprise.
Credit: NASA/Goddard Space Flight Center

Observations made by NASA instruments onboard an Air Force satellite have shown that the boundary between the Earth's upper atmosphere and space has moved to extraordinarily low altitudes. These observations were made by the Coupled Ion Neutral Dynamics Investigation (CINDI) instrument suite, which was launched aboard the U.S. Air Force's Communication/Navigation Outage Forecast System (C/NOFS) satellite on April 16, 2008.

The CINDI suite, which was built under the direction Principal Investigator Rod Heelis of the University of Texas at Dallas, includes both ion and neutral sensors and makes measurements of the variations in neutral and ion densities and drifts.

CINDI and C/NOFS were designed to study disturbances in Earth's ionosphere that can result in a disruption of navigation and communication signals. The ionosphere is a gaseous envelope of electrically charged particles that surrounds our planet and it is important because Radar, radio waves, and global positioning system signals can be disrupted by ionospheric disturbances.

CINDI's first discovery was, however, that the ionosphere was not where it had been expected to be. During the first months of CINDI operations the transition between the ionosphere and space was found to be at about 260 miles (420 km) altitude during the nighttime, barely rising above 500 miles (800 km) during the day. These altitudes were extraordinarily low compared with the more typical values of 400 miles (640 km) during the nighttime and 600 miles (960 km) during the day.

The height of the ionosphere/space transition is controlled in part by the amount of extreme ultraviolet energy emitted by the Sun and a somewhat contracted ionosphere could have been expected because C/NOFS was launched during a minimum in the 11-year cycle of solar activity. However, the size of the actual contraction caught investigators by surprise. In fact, when they looked back over records of solar activity, they found that C/NOFS had been launched during the quietest solar minimum since the space age began.

This extraordinary circumstance is providing an unparalleled opportunity to study the connection between the interior dynamics of the Sun and the response of the Earth's space environment.

CINDI is a NASA sponsored Mission of Opportunity conducted by the University of Texas at Dallas. NASA's Explorer Program at Goddard Space Flight Center, Greenbelt, Md., managed the CINDI mission. The Explorer Program provides frequent flight opportunities for world-class scientific investigations from space within heliophysics and astrophysics.

The CINDI investigation is carried out as an enhancement to the science objectives of the C/NOFS satellite undertaken by the Air Force Research Laboratory and the Space and Missile Command Test and Evaluation Directorate.


Story Source:

The above story is based on materials provided by NASA/Goddard Space Flight Center. Note: Materials may be edited for content and length.


Cite This Page:

NASA/Goddard Space Flight Center. "Boundary Between Earth's Upper Atmosphere And Space Has Moved To Extraordinarily Low Altitudes, NASA Instruments Document." ScienceDaily. ScienceDaily, 16 December 2008. <www.sciencedaily.com/releases/2008/12/081215121601.htm>.
NASA/Goddard Space Flight Center. (2008, December 16). Boundary Between Earth's Upper Atmosphere And Space Has Moved To Extraordinarily Low Altitudes, NASA Instruments Document. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2008/12/081215121601.htm
NASA/Goddard Space Flight Center. "Boundary Between Earth's Upper Atmosphere And Space Has Moved To Extraordinarily Low Altitudes, NASA Instruments Document." ScienceDaily. www.sciencedaily.com/releases/2008/12/081215121601.htm (accessed September 17, 2014).

Share This



More Space & Time News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

East Coast Treated To Rare Meteor Sighting

East Coast Treated To Rare Meteor Sighting

Newsy (Sep. 16, 2014) — Numerous residents along the East Coast reported seeing a bright meteor flash through the sky Sunday night. Video provided by Newsy
Powered by NewsLook.com
Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) — Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
NASA’s Curiosity Rover Finally Reaches Long-Term Goal

NASA’s Curiosity Rover Finally Reaches Long-Term Goal

Newsy (Sep. 15, 2014) — After more than two years, NASA’s Mars Curiosity Rover reached Mount Sharp, its long-term destination. Video provided by Newsy
Powered by NewsLook.com
SpaceX's Elon Musk Really Wants To Colonize Mars

SpaceX's Elon Musk Really Wants To Colonize Mars

Newsy (Sep. 14, 2014) — Elon Musk has been talking about his goal of colonizing Mars for years now, but how much of it does he actually have figured out, and is it possible? Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:  

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile iPhone Android Web
      Follow Facebook Twitter Google+
      Subscribe RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins