Showing all posts about science
A map of the solar system for your own grand tour of the planets
4 February 2014
Back in the 1960’s the Jet Propulsion Laboratory, a US space agency, was keen to organise a “Grand Tour” of the solar system’s outer planets, by taking advantage of a planetary alignment that would occur in the late 1970’s. They hoped to send up to four automated probes to take a closer look at Jupiter, Saturn, Uranus, Neptune, and Pluto.
Funding cuts thwarted the idea, though NASA deep space probe Voyager 2, launched in 1977, was able to fly by Jupiter, Saturn, Uranus, and Neptune.
There won’t be another such alignment of the outer planets until well into the twenty-second century. But thanks to Pasadena based designer and illustrator Paul Rogers, who has created a map of the solar system for tourists, you may be able to plan your own jaunt about the planets in the meantime.
Originally published Tuesday 4 February 2014, with subsequent revisions, updates to lapsed URLs, etc.
RELATED CONTENT
astronomy, design, illustration, legacy, science
Not every moon is a moon, most are captured objects
9 January 2014
Here’s a 2010 photo, taken by the European Space Agency’s Mars Express probe, of Phobos, one of two… moons orbiting Mars. But that’s not a moon. And nor is Deimos, Mars’ second so-called moon. In reality they’re merely random rocks captured by the Red Planet at some point in the past.
Take a look at Earth’s moon. The Moon. It’s elegant, sizeable, and spherical. The same cannot be said of the rocks orbiting Mars, a couple of unfortunate asteroids that once strayed a tad too close to the fourth planet. Most of the outer planets of the solar system have moons similar in stature to Earth’s satellite, but they also host a bunch of minuscule, oddly shaped rocks, called moons simply because they orbit the planet in question.
It makes me think it is time to consider what really constitutes a moon. If Pluto can no longer be regarded as a planet, why then must every last rock that has been pulled into orbit by a planet, be called a moon? Surely such bodies should adhere — like planets, real planets — to some sort of criteria before being called a moon.
Being pretty much spherical, and of a certain size and mass, could form basic benchmarks, and anything under a certain size should be referred to as a captured object rather than a moon. Sorry Mars, but both your orbiting companions, Phobos and Deimos, are captured objects, not moons.
Originally published on Thursday 9 January 2014.
RELATED CONTENT
astronomy, legacy, Mars, Pluto, science
The Alcubierre Drive, a means of faster than light speed travel?
6 June 2013
Could NASA be developing a means of moving through space at speeds greater than light? Apparently so. The trick though to travel at speeds faster than light is to generate a space, rather than a craft, that exceeds light speed, and then slot a vessel into that space.
It’d be as if you were going down a water slide, or something, where the water is moving you, and you’re just along for the ride.
Traveling faster than light has always been attributed to science fiction, but that all changed when Harold White and his team at NASA started to work on and tweak the Alcubierre Drive. Special relativity may hold true, but to travel faster or at the speed of light we might not need a craft that can travel at that speed. The solution might be to place a craft within a space that is moving faster than the speed of light! Therefore the craft itself does not have to travel at the speed of light from it\’s own type of propulsion system.
Intriguing, if nothing else.
Originally published Thursday 6 June 2013, with subsequent revisions, updates to lapsed URLs, etc.
RELATED CONTENT
Single microbe theory, was it a bug that killed off the dinosaurs?
20 December 2012
The mass extinction that killed off ninety percent of animal, plant, and insect species on Earth around two-hundred-and-fifty-one million years ago, could be attributable to an ocean residing microbe called methanosarcina, thinks Massachusetts Institute of Technology researcher Daniel Rothman:
Called methanosarcina, this sea-dwelling microbe is responsible for most of the methane produced biologically even today. Rothman and his team discovered that methanosarcina developed the ability to produce methane 231 million years ago. While that ability came around too late to be single-handedly responsible for the link. However, mathanosarcina requires nickel in order to produce methane quickly. Nickel levels spiked almost 251 million years ago, likely because of a spike in Siberian lava from the volcanoes themselves. This indicates that methanosarcina was directly responsible for producing the methane that killed off an overwhelming majority of the Earth\’s species.
Bound to be hotly disputed but will surely make for a talking point or two over the year-end break.
Originally published Thursday 20 December 2012.
RELATED CONTENT
Back to the future, I met my parents before they met each other
29 October 2010
Twenty-five years on and people are still asking questions about 1985’s Back To The Future. One that consistently crops up regards the apparent inability of George and Lorraine, Marty McFly’s parents, to remember him, and the part he had in bringing them together, many years earlier.
And to a degree the question makes sense. It would certainly be easy to forget a person you knew only briefly — like for a week — from thirty years earlier. But surely you’d remember anyone who played a big, and very active, part in bringing you together with your future spouse.
The conundrum is this: you tend to remember the people who brought you together in life. You’d certainly remember the person who played Johnny B Goode in such dramatic fashion at the Enchantment Under The Sea dance. And, given that Lorraine had such a crush on Marty in 1955, she’s unlikely to have forgotten him altogether.
What can change over time though are individual perceptions and memories of a person. While I doubt George and Lorraine had forgotten Marty (aka Calvin Klein) all together, they would have forgotten exactly what he looked like after a while. Twenty to thirty years is a long time to remember something like that, more so when you don’t have a photo either.
Even so though, who in their right mind is going think their child, born years after the event, could possibly have had anything to do with their meeting? Can we get back now to simply enjoying repeat screenings of this classic, without the excess analysis?
Originally published Friday 29 October 2010, with subsequent revisions, updates to lapsed URLs, etc.
RELATED CONTENT
film, legacy, physics, science, science fiction
For the universe is a hologram and I have touched the sky
25 October 2010
All sorts of ideas have been devised in an effort to make sense of the universe, some more… notable than others. For instance, a couple of years ago New Zealand scientist Brian Whitworth speculated that the cosmos was just a giant virtual reality simulation (Internet Archive link).
Meanwhile US astrophysicist Craig Hogan, who in 2008 ventured that the universe is a hologram, is now preparing to test the idea, after spending the last couple of years building the world’s most precise clock.
Black hole physics, in which space and time become compressed, provides a basis for math showing that the third dimension may not exist at all. In this two-dimensional cartoon of a universe, what we perceive as a third dimension would actually be a projection of time intertwined with depth. If this is true, the illusion can only be maintained until equipment becomes sensitive enough to find its limits. “You can’t perceive it because nothing ever travels faster than light,” says Hogan. “This holographic view is how the universe would look if you sat on a photon.”
Originally published Monday 25 October 2010, with subsequent revisions, updates to lapsed URLs, etc.
RELATED CONTENT
astronomy, legacy, physics, science
We made it back to the future, but in a parallel universe
9 July 2010
If you’re a dyed-in-the-wool Back to the Future fan I hope you weren’t taken in by the claim that last Monday, 5 July, was “Future Day”. That being the day Marty McFly and Doc Brown arrived in the future when they travelled forward in time during 1989’s Back to the Future Part II.
The arrival of the time travellers from 1985 last Monday may not have been all bad though, had it have happened. In the twenty-five years since the release of Back to the Future, and only five years out from 2015 — the setting for much of Back to the Future Part II — we still have ground to make up in terms of matching some of the advances in technology seen in the movie trilogy.
So far we’re still lagging in the development of:
- Flying cars (actually they exist, but are far from in everyday use)
- Hoverboards
- Time travel
We have however made advances in other areas, with the advent of:
- The World Wide Web
- Smart phones
- High Definition TV (if that’s much of innovation really, considering we’ve had low-def TVs for years)
There’s still another five years to go though, perhaps by then we’ll at least have hoverboards that are able to match what we can do with skateboards today.
Originally published Friday 9 July 2010, with subsequent revisions, updates to lapsed URLs, etc.
RELATED CONTENT
film, legacy, physics, science, science fiction
You can travel no further back in time than 1955
18 August 2009
The Time Traveler’s Wife is the latest in a long line of time travel themed movies, and according to physicist Dave Goldberg, makes for a more realistic representation of time travel than most of the (fiction) served to date.
But this is interesting, time travel is (theoretically) only possible to points in time where a time machine already exists, according to Goldberg.
In other words, for Marty McFly to travel from 1985 to back to 1955, as he did in Back to the Future, a DeLorean like time machine would already need to have been in existence in 1955…
According to Einstein’s picture of the universe, space and time are curved and very closely related to each other. This means that traveling through time would be much like traveling through a tunnel in space — in which case you’d need both an entrance and an exit. As a time traveler, you can’t visit an era unless there’s already a time machine when you get there — an off-ramp. This helps explain why we’re not visited by time-traveling tourists from our own future. Futuristic humans don’t drop in for dinner because we haven’t yet invented time travel.
Of course the concept of time travel — in the form of the Flux Capacitor — did exist in 1955, it simply hadn’t taken physical form… does that count?
Originally published Tuesday 18 August 2009, with subsequent revisions, updates to lapsed URLs, etc.
RELATED CONTENT
film, legacy, physics, science, science fiction
Detecting and defending Earth from asteroids, other threats
29 September 2008
The Association of Space Explorers (ASE) is calling on the United Nations (UN) to co-ordinate efforts to defend Earth from “potentially catastrophic asteroid threats“.
The report asks the UN to assume responsibility for responding to potentially catastrophic asteroid threats. “For 4.5 billion years, we’ve been bashed continuously by asteroids. It’s time for that to stop,” former Apollo 9 astronaut Rusty Schweickart told the assembly. The ASE’s vision is first for a global information network, coordinated by the UN, that uses data from ground- and space-based telescopes to find, track and rate the risk of near-Earth objects (NEOs).
Originally published Monday 29 September 2008, with subsequent revisions, updates to lapsed URLs, etc.
RELATED CONTENT
Uneven heat emission sending Pioneers 10 and 11 off course
7 July 2008
The mystery surrounding the unexplained course deviations of deep space probes Pioneers 10 and 11, which are currently somewhere in the vicinity of the Solar System’s Kuiper Belt, may have been solved. At least partly, that is.
Slava Turyshev, of NASA’s Jet Propulsion Laboratory, has spent the last two years studying data from the probes, which were launched in the 1970s, and concluded that uneven heat build-up across their structures is causing the trajectory anomalies:
Pioneer 11 gives off heat in certain directions more than others. The uneven heat emission is enough to nudge the spacecraft off course, accounting for 28% to 36% of the anomaly detected when Pioneer 11 was 3750 million kilometres, or 25 times the Earth-sun distance, away from us.
Originally published Monday 7 July 2008.
RELATED CONTENT