Question: Hello! My name is Tyr. I’m 17 year old from Israel and in a few months I’m going to graduate from high school. I’ve been fascinated with physics, astronomy and mathematics since I was a little boy. When I was 10, I realized Israel is not moving forward in those fields, so for the last 5 years I’ve been making my plans on moving to the U.S. where I could pursue this dream. With the coming elections, though, it would seem that NASA is going to remain very underfunded and the job pool may remain small or even shrink. I was thinking about learning German or Swedish so I can go get a job at ESA or the university in Uppsala. What are your thoughts? Do you think I should move to Europe or to the U.S., or stay in Israel altogether and hope for the best? — Tyr
Answer: It is always useful to think beyond your country of origin when it comes to careers in the sciences. Most sciences are an international endeavor, and astronomy is no exception. Many astronomers originally from one country find employment, sometimes permanent, in other countries. It is difficult to predict where one might end-up, so the best course of action is to remain open to possibilities for employment in other countries.
Question: I am trying to calibrate New Horizons radiometry data and need flux of strong radio sources (Cas A, Cyg A, Tau A, and Vir A) at 7182 MHz. Is there a good catalog of this basic information (flux at nearby frequencies plus spectral index) readily available on the web, such as for amateur radio astronomers? My searches so far have turned up lots of specialized survey results and catalogs but not much I can apply to this simple task. — Dick
Answer: You might try the NASA/IPAC Extragalactic Database (NED). As the name implies, this database contains a plethora of information on galaxies, including photometric information. Select the “photometric data point(s) and SED” link within the entry for each galaxy and search for the flux entry corresponding to the frequency you are looking for. For example, Cas A has a flux at 8250 MHz of 620 Jy (with an accuracy of +-4.8%).
Question: I’ve been interested in astronomy and all things space all my life and I’ve never taken the time to actually look into the job outlook until now. Everyone is telling me that if I become an astronomer then I won’t be able to support myself or pay off college. And that’s if I can even find a job. Everywhere I’m looking, I’m seeing that jobs available in the astronomy field and few and far between, a small pool of jobs for a larger pool of people and now all I can see is failure of I take this path. I’m a junior in high school and I can’t help but feel that I’m running out of time. I love astronomy and it hurts me that I might not be able to pursue that dream. Advice? — Taylor
Answer: I often tell students who are interested in pursuing a career in astronomy to make sure that they develop skills that will make them capable of obtaining jobs in related fields, such as physics, engineering, or computing. For example, most graduate students pursuing PhD degrees in astronomy develop marketable computing and data analysis skills which make them viable applicants to jobs in computing, software development, and even finance if they decide to pursue careers beyond astronomy. So, I think that if you, as most students pursuing advanced degrees in astronomy do, acquire good computing and data analysis skills, you should be able to develop a “backup plan” in the event that jobs become more difficult to secure in your chosen field of astronomy.
Question: Is there a way or a program available that will tell me what point on earth is 90° below it. For example for the sun and moon they show when the sun is 90° above a certain location. Can I find out the same thing for mercury and venus? — Steve
Answer: I think what you are asking for are the times when astronomical objects are at their highest point in the sky, otherwise known as “transit”. The Naval Observatory Data Services provides a nice web page which includes links to quite a few calculators which allow one to determine rise, set, and transit times for many astronomical objects.
Question: I am writing a piece for middle school students about the planets of our solar system and am trying to find an up-to-date figure for how many moons are officially recognized around Jupiter. I’ve seen figures from 23 to 49 and more pending. — Fiona
Answer: There are two good references to the number of “official” moons orbiting Jupiter. The first is a listing from NASA’s Jupiter Moons page, which lists 50 named moons plus an additional 17 “provisional” moon. I believe that provisional moons have not yet been assigned permanent names. The second source of this listing is on Scott Sheppard’s Jupiter Satellite and Moon page, which lists 67 as of March 2015. This second reference appears to list the sum of the 50 named moons plus the 17 provisional moons. For your summary I would use the total of named and provisional moons, or 67.
Posted in Moon, Planets
Tagged moon, planets
Question: I cannot find an answer to this conundrum anywhere on the Web, and it’s not at all a function of the famous Moon Illusion. Late last month (March), the full moon rose over a 7500-foot elevation ridgeline that’s located about 10 miles from my house patio viewing spot at 3500-foot elevation. While standing up I watched the top half of the moon clear the ridgeline, but upon sitting down in a chair I noticed the view of the moon had been reduced to a mere sliver.
I understand that refraction considerations might play into this, but really? to that great a degree? Essentially, the effect of a 3-foot vertical difference in my viewing height resulted in half the rising moon being obscured by the ridgeline. However, a tiny 3-foot difference distributed over 10 miles of horizontal distance seems to me as if it’d be way too small to result in any appreciable change of moon-viewing angle/perspective. What else could I be missing here? — Rick
Answer: I believe what you observe is due to your proximity to the mountain that is approximately 4000 feet above your point of observation and not due to refraction. Now, to cause the Moon to go from half-blocked to only slightly blocked by a nearby mountain, I would think that you would need to be closer than 10 miles, though.
Question: Hi, I am an undergraduate freshman at University of California, Berkeley. I am interested in astronomy and currently in the path of an Astrophysics major. My question is, what is the most important advice you can give to a college undergraduate pursuing a suitable graduate school at the field of study he/she is in. I find it difficult to keep my GPA up and I’ve been reading that your GPA does not matter however it does in terms of finding research early on and applying to graduate school. Right now, I believe the most important thing to do is to look for research and find connections.
Answer: You hit the nail on the head with your last sentence. Grades are one piece to an undergraduate’s application to graduate school. The other components are GRE scores, letters of recommendation, and research/publications that the undergraduate has participated in as an undergraduate. It is best to treat all of these factors as equally important, as there is no formula which weights one factor more or less than the other when it comes to the evaluation of graduate school applications. So, I would say that you have the right idea in that you should get involved in research early in your undergraduate career. A demonstration that you are keenly interested in astrophysics research through a strong undergraduate research record would definitely make your graduate school application much more attractive.
Question: There is talk of New Horizons travelling to another object in the Kuiper Belt. The fly by will be at about 1900 miles, much closer than the fly by of Pluto. How are the distances of observation of these type of objects arrived at and why would there be a difference between the two? — Robert
Answer: The closest approach of New Horizons to Pluto was about 7800 miles. Spacecraft trajectories and flyby distances are determined by a number of factors, including the measurement system used for determining the position and speed of a probe, the location from which these measurements are obtained, an accurate model of the solar system, and the availability of accurate models of the motion of a probe. There is a nice Scientific American article on this subject with more details. As for why the flyby of this new object, which is I believe a Kuiper Belt Object (KBO) called 2014 MU69, it is difficult to say. My guess is that the Pluto/Charon flyby imposed restrictions on how close New Horizons could get to Pluto based on the fact that it also had to get close to Charon, while the flyby of 2014 MU69 is a flyby of just one object, so they can get as close as they can.
Question: Is there ever day in Mars history where the Mars prime meridian is parallel to the prime meridian on the celestial sphere? If so what is it? For example on earth on 1950-3-21T04:35-21 spring equinox the earth prime meridian is parallel to the celestial sphere prime meridian. I am wondering if that ever happens with Mars and what that date would be if it ever happen. I don’t think its as easy as just saying spring equinox on Mars means the same thing. — Steve
Answer: This is kind of a tricky question as the celestial meridian is defined as the great circle passing through the celestial poles, the zenith, and the nadir of a particular location. So, if you are standing on Mars the prime meridian of Mars will be exactly parallel to the celestial meridian twice per year, once during the Mars spring equinox then again during its autumnal equinox. Note that the two meridians cross (though are not strictly parallel) once each day.
Question: What is the true distance of the moon from the surface of the earth, since VLT @ Paranal can shoot a high powered laser to measure the distance? Based on surface temperatures recorded by NASA, it appears to be much closer than stated and potentially within the middle thermosphere. — Robert
Answer: From the nice description of the Moon’s distance from us provided by the Universe Today, the average distance to the Moon is on average 384,403 kilometers, which is about 238,857 miles. This distance is routinely measured using LIDAR (LIght Detection And Ranging) stations which bounce laser pulses off of the retroreflecting mirrors placed on the Moon by the Apollo astronauts. I am not aware of a LIDAR installation at the Very Large Telescope (VLT) observatory in Chile. The accuracy of these measurements is a few millimeters, which has allowed scientists to determine that the Moon is slowly moving away from us at a rate of about 3.8 cm (about 1.5 inches) per year.
Posted in Moon, Physics
Tagged moon, physics