Featured Research

from universities, journals, and other organizations

Cluster Makes An Effervescent Discovery: Space Fizzing With Thousands Of Bubbles Of Superheated Gas

Date:
June 20, 2006
Source:
European Space Agency
Summary:
Space is fizzing. Above our heads, where the Earth's magnetic field meets the constant stream of gas from the Sun, thousands of bubbles of superheated gas are constantly growing and popping.

This artist's impression shows the Earth's magnetosphere (in blue) embedded in the flow of the solar wind -- a gas of charged particles being constantly ejected from the Sun. The solar wind (coming from the left of the figure) interacts with the Earth's magnetosphere and forms a permanent shock area called 'bow shock' (yellow arc in the image). It forms in front of the 'nose' of the magnetopause (the external boundary layer of the magnetosphere).
Credit: Image courtesy of European Space Agency

Space is fizzing. Above our heads, where the Earth’s magnetic field meets the constant stream of gas from the Sun, thousands of bubbles of superheated gas are constantly growing and popping.

Related Articles


Their discovery could allow scientists to finally understand the interaction between the solar wind and the Earth’s magnetic field.

This exciting new view of near-Earth space has been made possible by ESA’s four-spacecraft flotilla, Cluster, and Double Star, ESA’s collaborative space mission with China. The spacecraft encounter the bubbles every time they are on the day-lit side of the Earth, at altitudes of between 13 and 19 Earth radii.

The bubbles, known as density holes, are regions of space where the density of gas suddenly falls by ten times but the temperature of the remaining gas leaps from 100 000 ēC to 10 000 000 ēC.

When Cluster first flew through the bubbles, George Parks, University of California, Berkeley, thought that they were just instrumentation glitches. "Then I looked at the data from all four Cluster spacecraft. These anomalies were being observed simultaneously by all the spacecraft. That’s when I believed that they were real," says Parks.

Somewhat similar bubbles have occasionally been encountered in the past by other spacecraft. They were called hot flow anomalies but Parks decided the bubbles he saw are significantly different.

He found their signature in Double Star data too. During every orbit, the spacecraft usually fly through 20–40 bubbles. By carefully correlating the different spacecraft readings, Parks and his collaborators learnt that the bubbles expand to about 1 000 kilometres and probably last about 10 seconds before bursting and being replaced by the cooler, denser solar wind.

The energy source to drive these bubbles is currently uncertain but there is strong circumstantial evidence that the collision of the solar wind with the Earth’s magnetic field, which forms a boundary known as the bow shock, is probably creating the energy to drive them.

Bow shocks exist throughout nature. The familiar place is at the front of a ship; the bow shock is the swell of white water that builds up and precedes the boat. Another is in supersonic air travel. As an aircraft flies faster than the speed of sound, the sound waves pile up in front of the plane. That energy is finally dissipated in the sonic boom that occurs.

The bow shock between the Earth’s magnetic field and the solar wind is similar in many respects. The big difference is that scientists do not know how the energy in the magnetic bow shock is dissipated. This is to say they do not know what the equivalent of the sonic boom is. The newly discovered bubbles might provide a clue.

It is possible that they are caused by the energy that piles up at the bow shock – however, being certain is a long way off yet.

"For now, our job is to study them as thoroughly as possible. Then we will try to simulate them on computers and finally we will know what effect they have," concludes Parks.

The findings appear in the article "Larmor radius size density holes discovered in the solar wind upstream of Earth’s bow shock", by George Parks et al., published in the Physics of Plasmas journal (13, 050701; 2006).


Story Source:

The above story is based on materials provided by European Space Agency. Note: Materials may be edited for content and length.


Cite This Page:

European Space Agency. "Cluster Makes An Effervescent Discovery: Space Fizzing With Thousands Of Bubbles Of Superheated Gas." ScienceDaily. ScienceDaily, 20 June 2006. <www.sciencedaily.com/releases/2006/06/060620170614.htm>.
European Space Agency. (2006, June 20). Cluster Makes An Effervescent Discovery: Space Fizzing With Thousands Of Bubbles Of Superheated Gas. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2006/06/060620170614.htm
European Space Agency. "Cluster Makes An Effervescent Discovery: Space Fizzing With Thousands Of Bubbles Of Superheated Gas." ScienceDaily. www.sciencedaily.com/releases/2006/06/060620170614.htm (accessed October 31, 2014).

Share This



More Space & Time News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Antares Liftoff Explosion

Raw: Antares Liftoff Explosion

AP (Oct. 29, 2014) — Observers near Wallops Island recorded what they thought would be a routine rocket launch Tuesday night. What they recorded was a major rocket explosion shortly after lift off. (Oct 29) Video provided by AP
Powered by NewsLook.com
Raw: Russian Cargo Ship Docks at Space Station

Raw: Russian Cargo Ship Docks at Space Station

AP (Oct. 29, 2014) — Just hours after an American cargo run to the International Space Station ended in flames, a Russian supply ship has arrived at the station with a load of fresh supplies. (Oct. 29) Video provided by AP
Powered by NewsLook.com
Journalist Captures Moment of Antares Rocket Explosion

Journalist Captures Moment of Antares Rocket Explosion

Reuters - US Online Video (Oct. 29, 2014) — A space education journalist is among those who witness and record the explosion of an unmanned Antares rocket seconds after its launch. Rough Cut (no reporter narration) Video provided by Reuters
Powered by NewsLook.com
Rocket Explosion Under Investigation

Rocket Explosion Under Investigation

AP (Oct. 28, 2014) — NASA and Orbital Sciences officials say they are investigating the explosion of an unmanned commercial supply rocket bound for the International Space Station. It blew up moments after liftoff Tuesday evening over the launch site in Virginia. (Oct. 28) Video provided by AP
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:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

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