A Formica ant suspends a drop of aphid honeydew between her mandibles (which bristle with 7 or more teeth), as she drinks it. 
		Photo courtesy of Alex Wild, copyright, used with permission.WonderQuest:  On the web since 1997...      

Home   Top 10    Newsletter   Answer a question    Site Map   Fast answers 
Solving mysteries
WonderQuest

with April Holladay
New!  WeatherQuesting
 
Google
 
Web www.WonderQuest.com

     
RSS Add to Google

Answers About:  

   Animals
   Humans  
   Astronomy 
   Physics
   Mathematics 
   Evolution/Genetics
   Earth 
   Technology
   Plants
   Airspace 
   Sky
   Art, TV, music...  
   Food 
   Oceans/climate 
   Chemistry
   Computers
   Microcreatures

Special Features:  

   Current Column
   Teachers' corner
   Newsletter
   Answer a question
   Interact with nature

Question for readers to answer:

Can an average person develop the skill to reliably detect liars?

To clarify:  this question is similar to - Can an average person improve at hiding and detecting 'tells' in poker?  Also, consider only deliberate lies intended to harm another and, please, expound on the reasons backing your answer.

Deadline:  June 29, 2009.  We will publish the best answers on  July 13.

You get the credit.

Click here to give me your answer: Answer the question.


Interacting with nature by K:

How to Offer Wild Birds Shelter in the Winter

Not all birds migrate south for the winter.  Winter is a hard season for birds, and many risk freezing to death at night. It doesn't take much effort or money to provide shelter for them, and it can make a huge difference to the little feathered guys!

More Articles >>

 

 

Heavy Earth

Q: The earth gets heavier each day with the meteors and space debris that lands. Does Earth ever lose weight? If not, wouldn't Earth eventually get so heavy so as to affect its orbit?

A: Earth does indeed get heavier with landing space debris--several tons of dust and micrometeorites, alone, hit Earth's atmosphere each day. When you include the big rocks that actually impact Earth, this debris adds up to 40,000 metric tons a year.

Figure: [NOAA] The launch of TIROS I, the birth of the meteorological satellite system in 1960.

Does Earth throw off weight at anything like this rate, you ask. The two ways Earth might are: hot atmospheric molecules escaping Earth's gravity or launched space vehicles. I asked the National Oceanic and Atmospheric Administration (NOAA) how much atmosphere do we lose each year.

"I do not have definitive information... but [outgoing material] is so insignificant relative to the mass of the Earth that the ratio would be a decimal followed by all the 0's you could put on this page," says Russ Schnell, Director of the NOAA Observatory Operations in charge of collecting atmospheric data.

That leaves space programs. About 5,000 satellites have been launched since Sputnik 1 took off in 1957. Suppose all those satellites were still in space and as large as 3.5-metric tons (a larger than average satellite).

Then all the satellites the world has ever launched would total 17,500 metric tons of mass--which is only about 0.000000001 of one percent of the meteor mass that has landed on Earth. The number of zeros following the decimal place doesn't fill a page but it's still a pretty small number.

We can, therefore, forget about Earth bailing out mass. She doesn't, at least not compared to what lands on her.

Now the question remains. Over the eons, has Earth picked up enough mass from falling space debris to affect her orbit? This mass adds up to about ten raised to the 14th power metric tons, assuming Earth has always added weight at the present rate of 40,000 metric tons per year. That total seems like a lot until you compare it to the immense size of Earth. Then it dwindles to a pathetic 0.000003 of one percent of the mass of Earth. Negligible.

Accumulating space debris over the years has not affected Earth's orbit around the Sun one whit.

Further Surfing:

Cornell U, Ask a Scientist

Cosmic and heliospheric learning center

 

 

Return to Home

Site Map

Question Archive Features Info
Animals Sky ▪  WonderQuest's ▪  Correspondents' Contributors
Humans Art, TV, music   Ask a question   Interact with nature About April
Astronomy Food   Top 10 questions   April's blog
Mathematics Oceans & climate    Forum   Newspapers with WonderQuest:
Evolution & genetics Chemistry   Answer the question     Globe and Mail
Earth Computers   Newsletter     Happy News
Technology Microcreatures   Further reading     Corrales Comment
Plants     Fast answers    
Aerospace USA Today   Teachers' science corner   Advertising

Copyright 2008 by April Holladay  

Please note: We use third-party advertising companies to serve ads when you visit our website. These companies may use information (not including your name, address, email address, or telephone number) about your visits to this and other websites in order to provide advertisements about goods and services of interest to you. If you would like more information about this practice and to know your choices about not having this information used by these companies, or to opt out, click here: Google ad and content network privacy policy