Hendrik Christoffel "Henk" van de Hulst FRS (Utrecht, November 19, 1918 - Leiden, July 31, 2000) was a Dutch astronomer and mathematician. In 1944, while a student in Utrecht, he predicted the existence of the 21 cm hyperfine line of neutral interstellar hydrogen. After this line was di...
Shenzhou 1 launched on November 19, 1999, was the first unmanned launch of the Shenzhou spacecraft. The spacecraft used was not equipped with a life support system or an emergency escape system. After orbiting the Earth 14 times, the command for retrofire was sent by the Yuanwang 3 tracking ship off...
Orbital elements:
2011 WN2 Earth MOID = 0.0202 AU
Epoch 2011 Aug. 27.0 TT = JDT 2455800.5 MPC
M 331.55600 (2000.0) P Q
n 0.27034334 Peri. 208.44720 +0.15547736 -0.98497986
a 2.3687847 Node 232.70649 +0.92327468 +0.17193211
e 0.5858350 Incl. 5.41755 +0.35127007 -0.01593789
P 3.65 H 25.3 G...
Orbital elements:
2011 WQ2 Earth MOID = 0.0093 AU
Epoch 2011 Aug. 27.0 TT = JDT 2455800.5 MPC
M 342.98471 (2000.0) P Q
n 0.27109333 Peri. 336.90773 +0.86509310 -0.49874720
a 2.3644139 Node 53.11851 +0.47002926 +0.76873112
e 0.5848339 Incl. 3.83706 +0.17517543 +0.40037943
P 3.64 H 26.1 G 0...
Young astronomer captures a shadow cast by Jupiter Shadows are created when a source of light is blocked. Obvious, right? Also obvious is the brighter the source, the easier it is to see the shadow cast. So you might wonder, how faint an object can you use as a light source and still be able to detect a sha...
Baader Hyperion 8mm Eyepiece 1.25" Baader Planetarium Hyperion 68° Wide Angle Modular Eyepieces offer world-class performance and unique photo-visual features, at an unheard of price. Baader Planetarium has worked hard to give the Hyperions the world's finest optical coatings, superb...
NASA to support IU astronomer's quest to develop largest-ever star formation database By integrating the measurements of the electromagnetic radiation of galaxies from four projects -- the two space missions Galaxy Evolution Explorer (GALEX) and Wide-Field Infrared Survey Explorer (WISE),...
Orbital elements:
2011 WO2 Earth MOID = 0.0089 AU
Epoch 2011 Aug. 27.0 TT = JDT 2455800.5 MPC
M 348.20259 (2000.0) P Q
n 0.38292777 Peri. 100.83926 +0.95721468 +0.28842744
a 1.8781264 Node 242.40039 -0.27476299 +0.88045779
e 0.5650567 Incl. 1.51596 -0.09080394 +0.37630265
P 2.57 H 25.4 G...
Orbital elements:
2011 WM2 Earth MOID = 0.1699 AU
Epoch 2011 Aug. 27.0 TT = JDT 2455800.5 MPC
M 337.34276 (2000.0) P Q
n 0.51059735 Peri. 313.75342 +0.95730548 -0.17372074
a 1.5503045 Node 57.55104 +0.27210668 +0.81135248
e 0.2856593 Incl. 15.89090 -0.09759184 +0.55814716
P 1.93 H 20.2 G...
Orbital elements:
2011 WL2 PHA, Earth MOID = 0.0017 AU
Epoch 2011 Aug. 27.0 TT = JDT 2455800.5 MPC
M 7.62483 (2000.0) P Q
n 0.88000863 Peri. 88.89289 +0.51090354 +0.84934297
a 1.0784783 Node 212.93236 -0.85331450 +0.48239048
e 0.2832761 Incl. 14.12193 -0.10407660 +0.21428005
P 1.12 H 20....
Orbital elements:
2011 WK2 Earth MOID = 0.2276 AU
Epoch 2011 Aug. 27.0 TT = JDT 2455800.5 MPC
M 141.42218 (2000.0) P Q
n 0.71278904 Peri. 162.79771 -0.96212869 +0.19941944
a 1.2411627 Node 30.67087 -0.27259464 -0.70199436
e 0.0063211 Incl. 21.36676 -0.00074195 -0.68369277
P 1.38 H 21.1 G...
Orbital elements:
2011 WC Earth MOID = 0.1379 AU
Epoch 2011 Aug. 27.0 TT = JDT 2455800.5 MPC
M 250.29961 (2000.0) P Q
n 0.73777652 Peri. 244.92295 -0.35057333 -0.92911247
a 1.2129777 Node 226.13614 +0.90728660 -0.30577530
e 0.1092587 Incl. 9.39379 +0.23222697 -0.20796990
P 1.34 H 22.5 G 0...
Minus Violet Filters are used primarily to eliminating blue halos around bright stars in colour photography using refracting telescopes. They will to a lesser extent reduce visual chromatic aberration in achromatic refractors, (though a yellow filter will probably be better). The filter t...
