How to tell if life once existed on a planet and Phoenix lander goes dark

Welcome! "Alien Life" tracks the latest discoveries and thoughts in the various elements of the famous Drake Equation. You may notice that this and future entries are shorter than usual; career, family and book deal commitments have forced me to cut back some of my projects. Now, here's today's news:
g Life - If life were suddenly eliminated from the Earth, would a visitor from another planet be able to tell what once was here? Can the landforms of Mars tell us whether it once had a biota? Two UC Berkeley scientists conclude that life leaves a detectable but very subtle signature, including more rounded than angular hills. This was a surprise, since life has a big impact on erosion, both directly and through its effects on climate. See article. Note: This article is from 2006.
g Message -It is up to the present generation of astronomers to begin the survey of small solar system objects to determine if any of them seem to be artificial. We may have to observe many thousands of asteroids or comets to find a likely candidate. But "conventional" SETI searchers are used to laborious searches since they must investigate hundreds or thousands of stars in the hope of finding one communicative civilization. Perhaps a broadened search strategy will enlarge the likelihood of a successful detection. See article.
g Cosmicus -As it must to all spacecraft, silence has befallen Phoenix, the pioneering Mars lander that for five months has probed and sniffed the planet's high Arctic surface. See article.
g Imagining - Browse the local used bookstores for this volume, which examined the scientific plausibility of many alien creatures in "Star Trek": "To Seek Out New Life: The Biology of Star Trek". Published about four years ago, Athena Andreadis' book makes a good read, boosted by her background as a molecular biologist and neurosurgeon.