Astronomy Question: Amount of Matter in Our Universe?
Published May 4, 2012Mark asks,
Dear Astronomer,
Is the amount of matter in the Universe finite or infinite, and why do you think so?
Mark,
I’ll be the first to admit I’m more of an observational astronomer, and not much of a cosmologist or theoretical physicist.
That being said, the answer to your question varies depending on how you look at it. As far as matter you can see, touch, taste, or smell, there is a finite amount of it.
Since we can measure (roughly) the matter in the observable universe, and we know the universe is expanding, we’re actually in an exciting time where the density of matter in the universe is at a balance point.
However….. if you peer deep into the subatomic and “quantum” level – it could be said that there is an infinite amount of matter that pops into and out of existence. Since cosmology and theoretical physics are a bit out of my field, I’ll let ASU professor Lawrence Krauss help explain:
Carnival of Space #247
Published May 1, 2012
Carnival of Space
Carnival of Space #247 is available at Next Big Future!
This edition features great articles about:
Check it out at: nextbigfuture.com
Remember, if you’ve got a space-related blog, you really should consider joining the Carnival. It’s easy to participate – just email an entry to carnivalofspace@gmail.com, and the next host will link to it.
By participating, your writing will get more exposure, and you will also meet other bloggers in the space/astronomy community. You can also sign your blog up to host the Carnival of Space by sending an e-mail to the address above.
100 Billion Planets in the Milky Way?
Published May 1, 2012
A six-year search that surveyed millions of stars using the microlensing technique concluded that planets around stars are the rule rather than the exception. The average number of planets per star is greater than one. This means that there is likely to be a minimum of 1,500 planets within just 50 light-years of Earth.
The results are based on observations taken over six years by the PLANET (Probing Lensing Anomalies NETwork) collaboration, which was founded in 1995. The study concludes that there are far more Earth-sized planets than bloated Jupiter-sized worlds. This is based on calibrating a planetary mass function that shows the number of planets increases for lower mass worlds. A rough estimate from this survey would point to the existence of more than 10 billion terrestrial planets across our galaxy.
If you’d like to learn more about the PLANET collaboration, visit: http://arxiv.org/find/all/1/all:+AND+NETwork+AND+Anomalies+AND+Probing+Lensing/0/1/0/all/0/1
Source: NASA Image of the Day Gallery
Finals Week!
Published April 26, 2012
Pretty much my reaction during any final exam.
Yes, I know the image to the left is a meme that is almost as old as TNG itself. I couldn’t resist posting it since this semester’s finals are particularly rough. The nice thing is, next year I only have two classes (and my senior thesis), then I’m DONE with undergrad work.
Since it’s finals season, I haven’t had much time to blog the few weeks. Bear with me while I concentrate on getting my coursework wrapped up and my finals knocked out.
On top of everything else, I’ve been accepted to a pretty awesome observational observatory workshop at Mt. Wilson Observatory. I’m trying to make travel arrangements and come up with around a thousand dollars so I can cover part of the tuition, as well as plane tickets. Looks like I need to write some more (paying) articles!
That all being said, everything should be back on track by early May, and I’ll be back to posting regular content by then. I have some pretty cool stuff I’m working on. Keep your eyes peeled good buddies, 10-4?
Carnival of Space #246
Published April 25, 2012Carnival of Space
Carnival of Space #246 is available at Links Through Space!
This edition features great articles about:
Check it out at: http://http://linksthroughspace.blogspot.com/2012/04/carnival-of-space-246-here-at-links.html
Remember, if you’ve got a space-related blog, you really should consider joining the Carnival. It’s easy to participate – just email an entry to carnivalofspace@gmail.com, and the next host will link to it.
By participating, your writing will get more exposure, and you will also meet other bloggers in the space/astronomy community, after all, community is what blogging is all about. You can also sign your blog up to host the Carnival of Space by sending an e-mail to the address above.
Target Asteroids!
Published April 19, 2012
Not quite what NASA has in mind when they ask people to target asteroids.
Many of you know by now, I’m quite the citizen science junkie. Any way that people can make contributions to real science is a major “win” in my book. Recently, NASA announced a new outreach project that aims to enlist the help of amateur astronomers in discovering near-Earth objects, and study their characteristics. The project is aptly named, “Target Asteroids!” and will help support NASA’s Origins Spectral Interpretation Resource Identification Security – Regolith Explorer (OSIRIS-REx) mission.
Scheduled for launch in 2016, the OSIRIS-Rex mission will help our understanding of near-Earth objects by studying the properties of asteroids, measuring their non-gravitational forces and provide observations that can be compared with data obtained by telescope observations from Earth. In 2023, OSIRIS-REx will return back to Earth at least 2.11 ounces (60 grams) of surface material from the asteroid.
“Asteroids are a rich and accessible historic archive of the origin of our Solar System and life, a valuable source of mineral resources, and potentially hazardous Earth impactors that civilization must learn to deal with,” said Dante Lauretta (University of Arizona). “Our mission will address all these issues.”
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