Curiosity takes us to Mars

You’ve seen plenty of media coverage already about NASA‘s Curiosity roverlanding safely on Mars. It went better than they’d hoped. Now the robot will sniff around the red planet for signs that life might ever have existed there. What it finds could tell us all sorts of things about how life began here on Earth, or about the likelihood of life elsewhere in the universe.

Its primary mission will last one Martian year (about 98 of our weeks, nearly two Earth years). But with some luck it’ll keep going longer than that.

You can read about how the mission’s going on NASA’s mission web site; here’s part of today’s:

On its first Martian day, designated Sol 0, the rover is checking its health and measuring its tilt. All Sol 0 spacecraft activities appear to have been completely nominal. These include firing all of Curiosity’s pyrotechnic devices for releasing post-landing deployments. Spring-loaded deployments, such as removal of dust covers from the Hazard-Avoidance cameras (Hazcams) occur immediately when pyros are fired. Curiosity also took images with its front and rear Hazcams both before and after removal of the dust covers, checked out its UHF telecommunications system and rover motor controller assembly, and completed all activities required to proceed with its planned activities on Sol 1. Approximately five megabytes of data were successfully relayed back to Earth from NASA’s Mars Odyssey spacecraft during its overpass today.

Activities planned for Sol 1 during the mission’s approximately one-month characterization activity phase include deploying Curiosity’s high-gain antenna, collecting science data from Curiosity’s Radiation Assessment Detector and Rover Environmental Monitoring Station instruments, and obtaining additional imagery. The mission’s characterization activity phase is design to learn how all Curiosity’s subsystems and instruments are functioning after landing and within the environment and gravitational field of Mars.

There are lots of photos of Curiosity’s surroundings on Mars too, though you can’t get away from them if you’re near a TV or newspaper these days. I’m looking forward to a constant stream of fascinating info from Curiosity.

Curiosity’s first color image of the Martian landscape. This view of the landscape to the north of NASA’s Mars rover Curiosity was acquired by the Mars Hand Lens Imager (MAHLI) on the afternoon of the first day after landing. In the distance, the image shows the north wall and rim of Gale Crater. The image is murky because the MAHLI’s removable dust cover is apparently coated with dust blown onto the camera during the rover’s terminal descent. Images taken without the dust cover in place are expected during checkout of the robotic arm in coming weeks. Click the image above to embiggen.

European space concepts enter competition

From the BBC: the European Space Agency has selected four new mission concepts to compete for a launch opportunity at the start of the 2020s.

  • Large Observatory For X-ray Timing (LOFT): The mission would go after the fast-moving, high-energy environments that surround black holes, neutron stars and pulsars – objects that can produce sudden and very rapid bursts of X-rays. By observing this emission, scientists would hope to address questions related to fundamental physics: they could probe the effects of matter entering ultra-strong gravitational fields and ultra-dense states. They could also measure more accurately the mass and spin of black holes; and in the case of the biggest such objects in the Universe, this has something interesting to say about how they, and the galaxies that host them, formed.
  • Space-Time Explorer and Quantum Equivalence Principle Space Test (STE-Quest): Again, this mission would address some big physics topics. One objective would be to test “the equivalence principle”, which underpins several fundamental assumptions including the idea that gravity will accelerate all objects in a vacuum equally regardless of their masses or the materials from which they are made. The Apollo 15 astronaut Dave Scott famously demonstrated this principle when he dropped a hammer and feather on the Moon in 1971 and both hit the surface at the same time. STE-Quest would put very sensitive instrumentation on an orbiting to do a far more precise test of whether gravity really is so blind or perhaps varies on some scales.
  • MarcoPolo-R: This is an idea that has been around for a while. The mission would attempt to return a sample of material from an asteroid for detailed analysis in Earth laboratories. The most primitive asteroids contain geochemistry not observable in Earth rocks because they are constantly recycled. As such, asteroids can tell scientists a lot about conditions in the early Solar System, and about the original “stuff” that went into making the planets billions of years ago. One potential target is actually two asteroids in close proximity – a binary known as (175706) 1996FG3. The larger rock is about 1.5km across; its companion is less than half a km in diameter.
  • Exoplanet Characterisation Observatory (ECHO): This is a 1.2m telescope that would study planets circling far-away stars. In recent years, hundreds of these so-called exoplanets have been detected, but we no precious little about them yet. Echo would observe the planets as they moved in front of their stars. From the way the light is attenuated, the telescope’s detectors would be able to probe the atmospheres of these worlds. Echo would look for the presence of molecules such as ozone and carbon dioxide in the atmospheres. These and other markers might tell us something about whether any of the exoplanets have conditions capable of supporting life.

Biggest colour night-sky image ever

It’s cool space news time over at the BBC:

Astronomers have released the largest ever colour image of the whole sky, stitched from seven million images, each made of 125 million pixels.

The Sloan Digital Sky Survey has helped to identify hundreds of millions of cosmic objects. Researchers have also released an animation on YouTube demonstrating how the incredibly high-resolution image is represented on the celestial sphere.

Physics laws local?

According to a New Scientist article there are some preliminary astronomy results that at least one of the universal “constants” may be different in different parts of the universe.

At the centre of the new study is the fine structure constant, also known as alpha. This number determines the strength of interactions between light and matter.

A decade ago, Webb used observations from the Keck telescope in Hawaii to analyse the light from distant galaxies called quasars. The data suggested that the value of alpha was very slightly smaller when the quasar light was emitted 12 billion years ago than it appears in laboratories on Earth today.

Now Webb’s colleague Julian King, also of the University of New South Wales, has analysed data from the Very Large Telescope (VLT) in Chile, which looks at a different region of the sky. The VLT data suggests that the value of alpha elsewhere in the universe is very slightly bigger than on Earth.

New techniques for finding new planets

One of the astronomical activities that excites me most is the search for other planets outside our solar system. I’ve mentioned the Kepler probe before as one example – and, so far, a very successful one – of this planet-hunting.

But how do we find these planets? Although we have some pretty powerful telescopes planets are, relative to their distance in other star systems, very small. Experiments like Kepler find planets by making use of the fact that these planets – like the planets in our solar system – orbit around their stars. Sometimes those orbits line up so that when we’re looking at that system’s star the planet moves through our field of vision, across the front of our view of the star. If it does we can’t see the planet itself (it’s still too small) but we can see a tiny drop in the brightness of the star. But measuring how much the star’s brightness diminishes we can get an idea of how big it is. By measuring how frequently it transits in front of its star we can get an idea of how long its orbit takes. They can still only detect fairly large planets this way, though.

Now scientists in Germany, Bulgaria and Poland have developed another method to find even smaller planets. If there are other, smaller planets in a system where they’ve already detected a large planet using the transit method, then the smaller planets will make their presence felt – via gravity – on the large planet. The tugs of gravity will affect the orbit of the large planet and we’ll observe variations in the timing of the large planet’s orbit. Using computer models we can then infer the presence of the small planets, despite being far too small to see directly.

[via ScienceDaily]

Flags and stars

This post on Scienceblogs’ Starts With a Bang talks about national flags around the world that have stars – or, even more accurately, constellations – on them.

It also talks about the different tips to find the north and south polar stars using constellations as guides. Having lived most of my life in the northern hemisphere I was aware of the simple method for finding Polaris: you use the two edge stars of the Big Dipper to point the way.

It looks like finding the southern celestial pole is trickier, though, with a complicated combination of the Southern Cross and two nearby “pointer stars”. I’m eager to wait for clearer nightime skies to give that a try.

Kepler: the first data, and hundreds of possible new planets

Remember Kepler? It’s the space probe with a mission to locate planets that are similar to our own (which are our best bet to start looking for life, or at least life we’d recognise). It launched in March 2009, and started looking in June of that year.

NASA has been collecting, reviewing, and categorising that data. Today they’ve released the first bit of it.

Here’s a summary from Dynamics of Cats: check that out for links to more detail.

306 new candidate exoplanets, with 5 multiple transiting systems – ie stars with more than one planet transiting them.

The really interesting systems though are the 400 objects that the Kepler team got permission to withhold, and the data on which will be released later.

Statistically 100+ of those ought to be real planets, and probably the most interesting of all the exoplanets they found.