Astronomers have used Hubble to measure the distances to stars in nineteen galaxies more accurately than previously possible. They found that the Universe is currently expanding faster than the rate derived from measurements of the Universe shortly after the Big Bang. If confirmed, this apparent inconsistency may be an important clue to understanding three of the Universe's most elusive components: dark matter, dark energy and neutrinos.

I'll be on David Livingston's the Space Show this Friday, 27th May, to talk about my new "Case for Moon". It's main themes are: first, the Moon as our natural first destination in the solar system. Then, planetary protection and biologically reversible human exploration as core principles for human space exploration. Then, the Moon as a gateway for human exploration of the entire solar system, not just Mars.

One belief is that Jupiter's moon Europa has a deep, hidden ocean of salty liquid water beneath its icy shell. Whether the Jovian moon has the raw materials and chemical energy in the right proportions to support biology is a topic of speculation and  the answer may hinge on whether Europa has environments where chemicals are matched in the right proportions to power biological processes. Life on Earth exploited such niches and still does today.

Using the oldest fossil micrometeorites - space dust - ever found, Monash University-led research has made a surprising discovery about the chemistry of Earth's atmosphere 2.7 billion years ago.

The findings of a new study published today in the journal Nature - led by Dr Andrew Tomkins and a team from the School of Earth, Atmosphere and Environment at Monash, along with scientists from the Australian Synchrotron and Imperial College, London - challenge the accepted view that Earth's ancient atmosphere was oxygen-poor. The findings indicate instead that the ancient Earth's upper atmosphere contained about the same amount of oxygen as today, and that a methane haze layer separated this oxygen-rich upper layer from the oxygen-starved lower atmosphere.

Unlike most asteroids, C/2014 S3 (PANSTARRS) was formed in the inner Solar System at the same time as the Earth itself, but was ejected at a very early stage and has not been baked by billions of years near the Sun.

Instead, it has been preserved in the best freezer there is: the Oort Cloud, a huge region surrounding the Sun like a giant, thick soap bubble. It is estimated that it contains trillions of tiny icy bodies.

C/2014 S3 (PANSTARRS) was originally identified by the Pan-STARRS1 telescope as a weakly active comet a little over twice as far from the Sun as the Earth. Its current long orbital period (around 860 years) suggests that its source is in the Oort Cloud, and it was nudged comparatively recently into an orbit that brings it closer to the Sun.

You can never predict what treasure might be hiding in your own basement - a year ago, a 1917 image on an astronomical glass plate from the Carnegie Observatories' collection shows the first-ever evidence of a planetary system beyond our own Sun. 

Here's what happened: about a year ago, the review's author, Jay Farihi of University College London, contacted our Observatories' Director, John Mulchaey. He was looking for a plate in the Carnegie archive that contained a spectrum of van Maanen's star, a white dwarf discovered by Dutch-American astronomer Adriaan van Maanen in the very year our own plate was made.

Are you keen on humans in space, but skeptical about colonization of Mars as our first objective for space exploration? Do you think we will start with settlements supported from Earth, such as we already have in inhospitable places such as Antarctica? Do you think our exploration should be open ended with science as a core objective, and planetary protection and reversible biological exploration as core principles?

If you are keen on Mars colonization, it is not hard to find a future vision to inspire you. Elon Musk has plans to send a hundred people at a time in his proposed "Mars Colonial Transporter" and found a city of 80,000, and eventually a million. He is due to reveal these plans at the IAC conference this September.

This is one of the questions I get asked most often since I started to cover the topic of asteroid impacts. Will humans will become extinct within a decade, or within a century? And can this happen through natural disasters? For instance if you watch the movies you may think there's a chance of a giant asteroid impact which will make us extinct. But what's the real situation? 

In case you haven't heard of it, Nibiru is a totally nuts idea. Yet it gets many people very scared. I started to get messages about it as a result of writing articles about asteroid impacts, and how we can detect and deflect asteroids. It is possible to have beliefs that don't make any sense if you look at them closely. For instance, if you believe that you can have a square with every point on its edges equally distant from its center in ordinary geometry - that's impossible. That's a square circle. Nibiru is a belief of this sort.