Answered Questions

Why was it significant that the Phoenix lander found ice on Mars? Haven't we known for some time that Mars has ice caps at its poles?

At the Phoenix landing site in the martian Arctic, we expected to find ice-cemented ground beneath dry permafrost. This kind of ice can form from condensing vapor just as do the polar caps on Mars. However, the small chunks of what appear to be pure ice (segregated ice) were a surprise. On Earth segregated...

July 24, 2008 More

I understand that the earths magnetic field periodically winds down to zero, then reverses North to south and that we are overdue the next reversal. Since the magnetic field plays a part in protecting the Earth from solar radiation, is there any evidence that environmental disasters/extinctions (possibly evolutionary bursts) have occoured at the periods when the magnetic field was zero.

No, there is no indication in the rock records of mass extinctions at times when the Earth's magnetic field changed polarity. However, the last polarity change took place nearly a million years ago, so we don't have much data on any possible smaller environmental effects. Probably the change takes place over thousands of years,...

July 23, 2008 More

I'm working on a nonfiction children's book about life in the solar system. I'm trying to find information on extremophiles. What are they? Do we have evidence they exist anywhere else in the solar system besides Earth? Who discovered their existence?

Good luck with your book! There is lots of information available on extremophiles (life that flourishes under conditions that we would consider extreme in terms of temperature, salinity, chemical environment, radiation, etc.). Do a search on Ask an Astrobiologist, or on Wikipedia, or look at any of the books that...

July 22, 2008 More

When NEAR Shoemaker orbitted 433 Eros, it did not detect in its year orbit (and successful touchdown) any satellites (according to what i've read). Now in '05 we discover Dysnomia. Is this a recent addition? Is this 'moon' projected to stay with Eris/Eros in its course since Eros' gravitational effects are so minute? Could this body be jostled about enough to impact Earth on its next 'scheduled' flyby?

You seem to be very confused. Eros is not Eris, any more than the letter i is the same as the letter o. Eris is a dwarf planet, larger than Pluto, in the outer solar system, with a moon Dysnomia. Eros is an asteroid, a thousand times smaller, in the inner solar system....

July 21, 2008 More

How come whenever a life-detection device is designed, like those on the Viking Landers and those being planned for ExoMars and the Mars Science Laboratory, it's never a microscope. It always ends up being like a GCMS or something built to detect a specific chemical or organic compound. Wouldn't a microscope provide much more definitive data?

You raise an excellent point, one that has frequently been debated among astrobiologists. At the time of Viking (more than 30 years ago) it would have been difficult to obtain the high resolution images needed and to transmit them to Earth. With today's technology, this would not be a problem, and we could transmit...

July 18, 2008 More

I am trying to find out who at NASA is still doing CELSS research, and what the state of CELSS research is at this point. CELSS standing for "Closed Ecological Life Support System".

Given NASA's current focus on the development of a new rocket and crew vehicle, there is currently no CELSS-type research being funded at this time within NASA. By CELSS-type research I mean the incorporation of biological processors into an integrated life support system. There remains considerable CELSS expertise in NASA (both at Kennedy Space...

July 17, 2008 More

So many people send in ridiculous questions about death planets and 2012 and planetary alignments. Really I am surprised at the lack of knowledge out there. I was reading Astronomy textbooks by the time I was 8 years old. It was fascinating stuff. And it becomes more fascinating every day. Planetary alignments were interesting 2,000 years ago to the folks who knew nothing of what it all meant. Now that we know what it means, and we know it means nothing, why do people still love that Astrology related stuff? And why don't people know more about Gravitational Waves, Black Holes, and really neat stuff like that?

I ask myself the same question every day. Some people like to think catastrophes are coming, but I wish they would pay attention to real issues that threaten the Earth, like global warming and loss of habitat, rather than falling for hoaxes like Nibiru and pole shifts.
David Morrison
NAI Senior Scientist

How long does it take to create intelligent life out of microbial life in the fastest possible way where the planets climate is stable?

We can't answer that question, since we have only one example of life to study. On Earth the time span from the first multicelled life to intelligence was a bit less than a billion years, but that really doesn't help answer your question about the "fastest possible way".
David Morrison
NAI Senior Scientist

Is there any scientific data that shows the earths magnetic poles are shifting faster over the past decades? When was the last magnetic polar shift on earth? If we think it happens in approximately 1 million year cycles, would that not be the pertinent question? If the earths magnetic poles shifted significantly or reversed, does anyone know for certain what the effects would be on the surface of the earth?

The magnetic poles are always shifting slightly, in response to both internal variations in the Earth's dynamo and to changes in the Earth's magnetosphere that are triggered by the Sun. There is no indication that these magnetic variations have increased recently. Wikipedia has good articles on Earth's magnetic field and on geomagnetic reversals. These reversals...

July 14, 2008 More

Is there a way to enter into the field of Astrobiology without a PhD? I only have an MS in Biochemistry. If so, what is the best inlet to get involved with this fascinating area of research?

Astrobiology research is no different from any other science: it is usually a team effort involving PhDs, lab techs, students, administrators, and other support personnel. One approach for you is to contact groups that are engaged in astrobiology research. Or you might consider related activity, such as science writing or teaching. There is room...

July 11, 2008 More