business learning training articles new learning business training opportunities finance learning training deposit money learning making training art loan learning training deposits make learning your training home good income learning outcome training issue medicine learning training drugs market learning money training trends self learning roof training repairing market learning training online secure skin learning training tools wedding learning training jewellery newspaper learning for training magazine geo learning training places business learning training design Car learning and training Jips production learning training business ladies learning cosmetics training sector sport learning and training fat burn vat learning insurance training price fitness learning training program furniture learning at training home which learning insurance training firms new learning devoloping training technology healthy learning training nutrition dress learning training up company learning training income insurance learning and training life dream learning training home create learning new training business individual learning loan training form cooking learning training ingredients which learning firms training is good choosing learning most training efficient business comment learning on training goods technology learning training business secret learning of training business company learning training redirects credits learning in training business guide learning for training business cheap learning insurance training tips selling learning training abroad protein learning training diets improve learning your training home security learning training importance

« May 2014 | Blog home | August 2014 »

July 2014

Part of my job is to answer questions from High School science teachers, and I love it! These last questions came from a teacher and her year 11/12 students. I thought the questions were good and showed the great depth that some students are thinking at, and also the great interest in science.

I hope I’ve given them justice. This stuff can get quite mind-warpy very quickly!

How do we know how many light-years away we are seeing - as in we have seen stars 13 million light-years away.

Redshift will tell us the velocity of galaxies away from us, then with a calculation as fundamental as c=fλ we can approximate it’s distance. BUT…It’s not a simple as that…of course! There are effects due to our atmosphere, relativity, gravitational lensing, objects in the way, expansion of space etc that get in the way of accurate measurements.

So, we have to KNOW the distance to a whole bunch of objects in order to compare that with others. There are a few ways to do this, either with cepheid variable stars, quasars, pulsars, and parallax. There are a couple of satellites that are tackling the problem with parallax that are very interesting.

Have a look at Hipparcos and Gaia. These two satellites are involved in Astrometry, a very interesting area in astronomy. Literally measuring the stars! The precision is amazing by the way. Gaia can detect a movement of a star of 10 microarcseconds, (or something like that) the equivalent of seeing the length that my hair grows in 10 minutes from a distance of 10 meters. The angle between the smallest division on a protractor is a degree, that’s made of 60 arc minutes, each one of those is 60 arc seconds, and then 10 1000ths of that!

With all of these methods, we can get some very accurate measurements.

The text book states that when the universe was one second old it was at least 1 light-year across but wouldn't that mean it was expanding faster than the speed of light?

YEP! It’s called inflation, and it is not very well understood! We talk about it as if we know what happened, but we really don’t! (like when we talk about how we know what the universe is made of, when we really only know what 4% of it is made of!) The experiment BICEP2 had a pretty close shave with the answer, but there is still some discussion, and of course we need to replicate the experiment.

Due to the fact that we don't understand inflation, we need to observe it and measure it, once that has happened, we can then start to try and figure out some details. So in order to measure it, we've tried to measure the effects of what that period would've done to the gravitational environment. In short, we're searching for gravity waves

If the universe started to collapse - could you travel fast enough to escape and can you exist outside the universe?

No. The idea of existence outside of a universe is, with our current understanding, non-sensical. If the universe collapsed, so would everything in it. The physical space between galaxies, stars, planets, etc would also collapse. Think of the usual stars (dots) on a balloon. If you deflate a balloon, the balloon also shrinks, the stars don’t move independent of the balloon, and interestingly (and in line with the analogy) the dots also get smaller!

The idea of “outside" the universe is not defined in physics (like dividing by 0, you just can’t do it. The idea of putting things into 0 groups is a non-sensical idea!) Space and time break down, we have no way of describing that condition mathematically or physically.


High school students in regional NSW had the chance to Kickstart their science studies when the outreach team from the University of Sydney's Faculty of Science visit Armidale, Broken Hil land Dubbo in terms 2 and 3 this year. Students got to interact with hands-on activities in Kickstart on the Road workshops.

Kickstart on the road with Science communicator Tom Gordon (right) and Physics students from Dubbo
"It's very exciting taking Kickstart on the Road out of the labs in Sydney," said Tom Gordon, Science Communicator and Kickstart Physics coordinator in the School of Physics at the University of Sydney.

Dr Cecily Oakley, Science Communicator in the School of Biological Sciences, said, "Our program aims not only to aid in exam preparation for these students, but to excite, intrigue and inspire them about the natural world."

Kickstart in the flagship outreach program for the University of Sydney Faculty of science, the Kickstart workshops are interactive with educational sessions specifically designed around the HSC Science syllabus. The Kickstart program runs regularly in Sydney, with over 5 000 high school students participating in the workshops each year. In fact, for Kickstart physics alone, almost one quarter of the entire physic cohort for the HSC visited the flagship outreach program in 2013.

The Kickstart on the Road workshops introduce students to specialist experiments and concepts and is a wonderful opportunity to take our program out of the University labs and into high schools in regional areas.

Kiri Simon, Tom Gordon and ABC Western Plains Mornings presenter Dugald Saunders.

"Not everyone can get to Sydney to see and experiments with equipment from a university lab - equipment that is used by university students and researchers," said Tom.

Kickstart activities and experiments are based on the HSC syllabus and Kickstart on the Road takes that a step further where we take the experiments into regional areas," said PhD student and Kickstart Tutor Fran van den Berg.

"If you want to do well in the HSC, this is the place to come," said Wagga Wagga student Patrick Byrnes. He continued, "It's great revision, the hands on approach and being able to talk to people that have done the HSC, they know what's up!"

"We are very excited to be able to bring the Kickstart program to visit students in regional NSW. We are bringing with us insects, superconductors, eyeballs, plasmas, brains and telescopes as well as some very talented and enthusiastic tutors." - Tom Gordon, Science communicator, School of Physics

"A benefit of the Kickstart on the Road Workshops is that it encourages students to consider that there's a lot more to science than what the HSC presents, that University open up a whole lot of doorways and experiences," said Kickstart tutor Liam Chalmers-Giddy.