NASA hit a meteorite, how #**^# is that!
Dr Lori Glaze, the director of planetary science at Nasa, was convinced something remarkable had been achieved by the mission.
"We're embarking on a new era of humankind, an era in which we potentially have the capability to protect ourselves from something like a dangerous hazardous asteroid impact. What an amazing thing; we've never had that capability before," she told reporters.
On the causes of mass extinctions
“The temporal link between large igneous province (LIP) eruptions and at least half of the major extinctions of the Phanerozoic implies that large scale volcanism is the main driver of mass extinction. It is increasingly widely thought that large igneous province (LIP) eruptions might be the driver of many of the purported proximal kill mechanisms, and the temporal link between volcanism and extinction is now well-established” www.sciencedirect.com
So volcanic eruptions and super volcano eruptions have been shown to be responsible for most of the extinction level events throughout Earth's history. The K-Pg boundary layer in Mexico's Yucatan province shows signs of meteorite impact yet underneath the iridium and tektites is volcanic ash, lava and volcanic glass. The theory now is of a double strike, first a volcanic eruption which formed the Deccan traps in India followed by a meteorite strike that finished off the vast majority of living species already struggling from the effects of the volcano.
So we have 2 different stories, meteorites/asteroids are a high priority menace and cause extinction level events V volcanoes are the major player in extinction level events.
Our activities are changing the climate.
Sea levels are rising and will continue to rise. Part of this rise is due to thermal dilation, warm water takes more space than cold. The rest of the rise is caused by ice sitting on land melting and running into the oceans. We are accelerating both processes and the 2nd one has a number of consequences linked to volcanism.
The glaciers have a weight, a colossal weight, the land freed of it's glacier load will rebound (isostatic adjustement). This is happening all over at the moment since the beginning of the current inter-glacial, the changes we are making to the greenhouse effect will amplify this effect. The rebound we are provoking will/is changing the stresses and pressures on earthquake fault lines and on volcanoes, this will trigger more volcanic eruptions. There are a whole load of active volcanoes under the Eyjafjallajökull ice sheet for example, when this ice sheet melts and runs off these volcanoes are very likely to erupt. The rebound will also trigger more earthquakes and they will be more violent, submarine earthquakes mean tsunamis and we have seen how destructive these can be. It should be noted that these effects have been seen in the past and most recently 10 to 12,000 years ago when the Earth came out of an "ice age" and into an inter-glacial. The isostatic adjustement caused a submarine tsunami off the coast of Norway that led to the drowning of at least a major part of Baffinland effectively separating England from Europe.
Water has a weight, 1 litre weighs around 1 kilo (4°C). Between 2002 and 2016 the antarctic Basin ALS21 has lost 748 gigatonnes of ice into the oceans. A gigatonne is 1,000,000,000 tonnes. The new water presses down on the ocean floor and bends it which increases volcanic and earthquake activity and tsunamis.
We know we are changing the greenhouse effect which is causing climate change and this is leading to glacier loss which is leading to the two effects noted above. We have no evidence that the changes we have made to the Earth's systems will "attract" more meteorites or asteroids.