flights visible from Modesto, CA
cepheids visible from Modesto, CA
distance from Mars to Jupiter
Google is a search engine. It tries to find web pages that it thinks are relevant to those searches. It is very sophisticated at this, so as to try to figure out what pages actually have the information, and which just happen to have the words. However, since these are things that probably no one has written about on the web, you get nothing really useful.
WolframAlphas is NOT a search engine. It treats those same queries as requests to try to answer them from its databases or by computing them from things that are in its databases. So, for the first it figures out that you are interested in scheduled airplane flights that you can see from a particular location. It has airline flight data and radar tracking data, and from that, and it's model of visibility, it figures out what planes could possibly be seen from Modesto, taking into account their last known position and heading and extrapolating to account for the fact that the radar data it gets is behind by something like 15 minutes. (Click on a flight in the resulting list, and it gives you neat information about it, such as when it took off, how late that was, a plot of its course, graphs of altitude vs. time, groundspeed vs. time, and heading vs. time).
The second is similar. It figures out that Cepheids are a kind of star, gets a list of the 100 brightest Cepheids, and figures out which are above the horizon at Modesto, CA, right now.
For the third, it decides you are talking about planets (although you can tell it you mean Jupiter, FL and one of the several cities named Mars if you wish), and from their orbital information (which it has in its database) it calculates where they are now, and tells you the distance between them.