[DOC] [TLE] About Comets - Lunar and Planetary Institute - USRA [PAR] Oct 31, 2012 ... As comets approach our Sun [within about 450 million kilometers (280 million ... 
As comets move close to the Sun, they develop tails of dust and ionized gas. ... 
Rarely, they are as long as 150 million kilometers (almost 100 million miles). ... 
Based on these orbital characteristics, short-period comets are... [DOC] [TLE] Earth & Space Science - Spring Branch ISD [PAR] Oct 5, 2015 ... As comets approach our Sun [within about 450 million kilometers (280 million 
miles)], they ... As comets move close to the Sun, they develop tails of dust and 
ionized gas. ... Rarely, they are as long as 150 million kilometers (almost 100 
million miles). ... Pluto and Eris are the best known of these icy worlds. [DOC] [TLE] What We Know About Comets - JStor [PAR] The earth has uandoubtedly encountered comets' tails scores and scores of .... 
Another remarkab]e fact is this: the orbits of all these bodies lie ..... as they 
approach the sun and expand as they recede from the sun. ... They fr6quently 
develop to enormous ... one time more than 100 million miles in length; that of 
1843 was at. [DOC] [TLE] The Outer Planets: Comets [PAR] Comet Hyakutake, seen right, came as close as 9.3 million miles of Earth in 
March 1996. Comets are completely frozen when they are far from the Sun, and 
most are just a few ... A comet's appearance changes as it approaches the Sun. ... 
Most comets actually have 2 tails: a plasma tail made of ionized gas, and a dust 
tail... [DOC] [TLE] Rosetta mission: What is it and why will it crash into a comet today? [PAR] Sep 30, 2016 ... Travelling further from the Sun than ever before and faced with a ... as it travelled 
some 497 million miles from the Sun, close to the orbit of .... Some comets escape 
from these regions and journey into the inner Solar ... do not develop a tail or a 
coma when they approach the Sun. ... Low estimate: 4 100 GBP. [DOC] [TLE] Health & Science: Comets show their tails on recent nights - Public ... [PAR] Dec 10, 2013 ... Some of these objects develop a visible tail and have the blurred ... Some of the 
tails are 1 million miles wide and 100 million miles long. ... These comets show 
off their beauty as they come toward our sun, ... Other comets break up when they 
approach the sun and some comets even collide with planets. [DOC] [TLE] HubbleSite - Reference Desk - FAQs - Hubble Space Telescope [PAR] All of these objects are held together in a group by the Sun's gravity. ... One 
astronomical unit equals the distance from Earth to the Sun: 93 million miles (149 
million km). Some of the comets associated with the solar system travel on orbits 
that take ... They have no rings and only two of them (Earth and Mars) have 
moons. [DOC] [TLE] Comets, Asteroids, Meteorites and Impacts [PAR] Some of the orbits aren't even elliptical - the comets just do one passage in 
toward the ... while the tails can be up to 1 A. U. in size (remember, 1 A. U. is 
about 100 million miles!). ... These include the gas tail (also called the ion tail), 
which is made up of ... Comets orbit the Sun, so they obey Kepler's laws, just like 
the planets. [DOC] [TLE] Halley's Comet - Wikipedia [PAR] Halley's Comet or Comet Halley, officially designated 1P/Halley, is a short-period 
comet visible .... The perihelion, the point in the comet's orbit when it is nearest 
the Sun, is just 0.6 .... a long tail, which may extend more than 100 million 
kilometers into space. ... Together, these observations suggested that Halley was 
in fact... [DOC] [TLE] Comet tail - Wikipedia [PAR] A comet tailand comaare features visible in comets when they are 
illuminated by the Sun and may become visible from Earth

Question: As they approach the sun, some of these develop tails as long as 100 million miles
Answer: a comet