On April 4, 2017, it was detected outbursting to magnitude 6.5. On April 19, 2017, it will reach its closest point to Earth of ~1.2 AU. At this point, it will be about apparent magnitude 8, and, assuming a size of 20 km, have an apparent size of 19 milliarcsecond. It will come to perihelion (closest approach to the Sun) on May 10, 2017. Read more
Comet C/2015 ER61 fragmentation event: some further data and some simple analysis
As you may have heard, comet C/2015 ER61 Panstarrs has recently experienced a nucleus splitting. We were among those who reported this event. Digging in our image archives, we have found evidence of that fragment in June 02 2017 images and could document the motion of the "b" component. Read more
Orbital elements:
2015 ER61 PHA, Earth MOID = 0.0140 AU
Epoch 2015 Mar. 19.0 TT = JDT 2457100.5 MPC
M 359.06688 (2000.0) P Q
n 0.00115781 Peri. 86.65541 +0.70031952 +0.70864328
a 89.8207997 Node 228.19643 -0.69212183 +0.64464169
e 0.9933428 Incl. 6.61648 -0.17469955 +0.28681319
P 851 H 11.9 G 0.15