Astronotes Armagh Planetarium's Stellar Blog! ... Planets . ... Our Galaxy . ... Weird and Fun . ... It came from another galaxy: This artistтАЩs impression shows HIP 13044 b, an exoplanet orbiting a star that entered our galaxy from beyond. ... HIP 13044 is one of tens of millions of stars in the тАЬHelmi streamтАЭ, stars that belonged to a dwarf galaxy consumed by our own Milky Way galaxy, some six to nine billion years ago. ... Tweets that mention ESO finds weird doomed planet from another galaxy | ...

Changing a World . What did the students learn from all this? ... The students found this unsatisfactory -- some of them would not be able to fit another astronomy class into their schedules, but they wanted to know about our planetary neighbors, and this project gave them the opportunity to find out without spending valuable class time on the subject. ... The students also learned to learn for themselves, perhaps one of the most important milestones during formal education. ...

Research questions include: . The solar system probably formed about 4.5 billion years ago from a giant disk of gas, dust and ice in space. ... All forms of life on Earth require liquid water to survive, so the presence of liquid water is a good criterion for deciding whether other planets in the universe could be habitable. Earth is the only habitable planet in the solar system. ... Planets and moons in the outer solar system are too cold for liquid water. ...

... Comet Bradfield Rising . ... Known as an extremophile, bacteria such as D. M27: Not A Comet . ... Comet C 2001 Q4 (NEAT) . ... Comet C 2002 T7 (LINEAR) . ... Discovered by the the Lincoln Near Earth Asteroid Research (LINEAR) project in October of 2002, comet C/2002 T7 is now visiting the inner solar system, making its closest approach (see animation by L. Koehn) to the Sun tomorrow, April 23rd. ... Comet Bradfield Passes the Sun . ... Right now, Comet Bradfield is passing the Sun. ... 2001 2002 . ...

... More on 51 Peg: . The discovery of a Jupiter--mass planet in orbit around the solar--type star 51Peg has been reported by Michel Mayor and Didier Queloz (Geneva Observatory) on October 6th at the 9th Cambridge workshop on "cool stars, stellar systems, and the sun" held at Florence (Italy). ... Recall that the measurements of radial velocity only yield v sin i which in turn gives us M sin i. For most values of i, sin i will be greater than 0.5 and this gives a mass estimate of 0.5 Jupiter masses. ...

... Bad Astronomy . Misconceptions . ... The Nine Planets . ... This is true, and so I have updated this page with a tidal force calculation. ... That way we can see right away how strong the other planets are; a gravity of 10 means the planet pulls on the Earth 10 times as much as the Moon does. ... So, in units of Moon gravity and tides, below are the forces on the Earth from rest of the planets (the data for masses and distances are from the wonderful page The Nine Planets ). ... 2008 Phil Plait. ...